In-situ synchronous experimental device, experimental method and application of animal exposure to atmospheric pollution

Abstract

The application belongs to the technical field of toxicity test, and discloses a kind of on-site synchronous experimental device, experimental method and application of animal atmosphere exposure, the device includes modular design and detachable connection main portable box and exposure experimental unit, vice portable box and experimental support unit, can be flexibly carried to various environmental event sites, and at any time, quickly carry out animal exposure experiment;Multiple exposure cabins, multiple concentration exposure experimental design can carry out multiple concentration gradient experiments in the same time, and can complete toxicity evaluation experiment in a shorter time.The device and method provided by the application can use on-site atmosphere as exposure research object at any time, carry out toxicity evaluation experiment of multiple concentration conditions environmental air in the same time, obtain more real and effective experimental data under real experimental conditions, to solve the problem of rapid health risk assessment of on-site pollution environment event and improve the accuracy of evaluation results.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of toxicity testing, and particularly relates to an on-site synchronous experimental device for animal atmospheric exposure, an experimental method and application. BACKGROUND

[0002] With the rapid economic development and accelerated urbanization process in recent years, the health standards for air pollution of the World Health Organization and governments of various countries have been gradually tightened. The assessment and management of health hazards of air pollution environmental events and the prevention research have become increasingly important. Therefore, it is very urgent to obtain scientific data through experimental devices (or simulation) to assess the health risks of humans or animals in actual pollution environments and further support the formulation of environmental protection and public health policies.

[0003] For experimental techniques of atmospheric environmental pollution and other environmental events, the current main methods are laboratory simulation of pollutant aerosol generation or environmental sampling followed by laboratory research. Since the composition of environmental air (aerosol) is very complex, and its components and concentrations are easily affected by environmental changes and undergo physical or chemical changes, the two commonly used methods lack authenticity and timeliness, and cannot quickly and truly evaluate the toxicity of the site of pollution and other environmental events.

[0004] In order to solve the problems existing in laboratory simulation, the Chinese invention application with publication number CN114145880A discloses a multi-channel modular animal inhalation exposure box and exposure system, which includes a test box, a side door hinged on the side opening of the test box, an inlet mist port, a detection port, an air inlet port and an air outlet port provided on the test box, and a test animal placed in the test box. The multi-channel modular animal inhalation exposure box of the invention is suitable for both dose-controlled and condition-controlled toxic exposure experimental research in the laboratory and outdoor exposure research in the actual environment, i.e., experimental animals can be exposed to aerosol particles, simulated toxic gases, tail gas, smoke and other substances, and can also be exposed to the actual atmospheric environment outside. The modular combination can simultaneously achieve exposure research of multiple animals, different target pollutants and different toxic doses. However, the patent application technology needs to use a test box with a large volume, a clean air bottle and other devices, and the overall equipment has a large volume, heavy weight, complex pipeline and is difficult to quickly deploy. The exposure cabin is arranged in parallel from top to bottom, and the side door can be opened to communicate with the outside air, but it cannot guarantee the consistency of the gas concentration entering the exposure cabin, and it is also difficult to accurately adjust the exposure concentration in each exposure cabin. Therefore, it cannot be automatically operated, and thus it is difficult to meet the needs of quickly deploying and quickly completing the exposure experiment at the site of environmental pollution events.

[0005] In terms of portability, the application with publication number CN114767318A discloses a portable animal respiratory exposure experiment system, which comprises a gas supply device, a particulate matter exposure cabin, a first hygrometer and a particulate matter detector, a vacuum pump and the like. The gas supply device comprises a large-volume air compressor, a vacuum pump and an aerosol generating device, and only one exposure cabin. The document does not disclose how to achieve portability. In fact, since each component is an independent structure, it needs to be disassembled, packed and boxed separately before transportation, and then unpacked and installed after transportation to the site. Due to the large volume and heavy weight of the air compressor, aerosol generating device and particulate matter exposure cabin, it is actually difficult to meet the needs of rapid packaging, transportation, unpacking, deployment and automatic operation.

[0006] Therefore, the existing animal atmospheric toxic exposure experiment equipment is large in size, heavy in weight and complex in pipeline, and cannot meet the needs of lightweight, centralized packaging, rapid carrying to the environmental pollution event site and rapid deployment for exposure experiment. At the same time, the number of exposure cabins is small, the pipeline connection is complex, the experimental method is complicated, multiple concentration gradient experiments cannot be carried out at the same time, the consistency of the distribution of on-site air pollutants (or aerosol particle size) in all concentration gradient experiment exposure cabins cannot be guaranteed, the accuracy of experimental data is affected, and the comparability between the obtained experimental data is poor. SUMMARY

[0007] In view of the above problems of the prior art, the purpose of the present application is to provide a lightweight, small-sized, simple-pipeline, fixed-box-contained and carried animal atmospheric toxic exposure on-site synchronous experiment device, experiment method and application. Through synchronous improvement of the device structure and the experiment method, the device is portable, the deployment and experiment steps are greatly simplified, multiple concentration gradient experiments can be carried out at the same time on site, the consistency of the distribution of on-site exposure gas (or aerosol particle size) in all concentration gradient experiment exposure cabins can be guaranteed, the device can automatically run and be accurately controlled, the accuracy of experimental data can be guaranteed, and the device can be further applied to atmospheric toxic exposure toxicity evaluation and rapid health risk assessment of atmospheric environmental pollution, thereby solving the above problems of the prior art.

[0008] The present application provides the following technical solutions to achieve the above purpose:

[0009] An animal atmospheric toxic exposure on-site synchronous experiment device, characterized in that it comprises a main portable box and an exposure experiment unit which are modularly designed and detachably connected, a secondary portable box and an experiment support unit.

[0010] Each component of the exposure experiment unit is arranged in the main portable box, comprising:

[0011] Triplex exposure chamber set, air extraction filter, air extraction mass flow controller, dilution air mass flow controller, dilution air filter;

[0012] Each component of the experimental support unit is arranged in the secondary portable box, including:

[0013] Direct current mobile power supply, positive pressure air pump, negative pressure air pump;

[0014] When in use, the main portable box and the exposure experimental unit, the secondary portable box and the experimental support unit are simultaneously carried to the site, and each component is connected to each other through the gas conveying connection pipe to form a triplex synchronous experimental device for animal atmospheric toxic exposure on site, and environmental event atmospheric toxic exposure experiment on site can be directly carried out, and low, medium and high concentration exposure experiments can be simultaneously carried out.

[0015] A synchronous experimental method for animal atmospheric toxic exposure on site, characterized in that it comprises the following steps:

[0016] S1, preparation of the synchronous experimental device on site

[0017] The main portable box and the exposure experimental unit of the synchronous experimental device for animal atmospheric toxic exposure on site, the secondary portable box and the experimental support unit are carried to the experimental (environmental event) site;

[0018] The upper cover of the main portable box and the secondary portable box is opened, each component of the exposure experimental unit and the experimental support unit is taken out, and then each component is connected through the gas conveying connection pipe or electrically connected through the wire to form a triplex synchronous experimental device for animal atmospheric toxic exposure on site;

[0019] S2, preparation of the synchronous animal exposure toxic experiment on site

[0020] The exposure experimental scheme is determined, including exposure dose, exposure process control, the control parameters of the animal exposure toxic experiment are determined, and the experimental animals are prepared;

[0021] S3, synchronous animal exposure toxic experiment on site

[0022] The experimental animals are divided into three groups of animals, which are loaded into one single exposure chamber of the triplex synchronous experimental device for animal atmospheric toxic exposure on site, the operating parameters of each part of the triplex synchronous experimental device for animal atmospheric toxic exposure on site are controlled, the triplex synchronous exposure process control is carried out, and the process is continued until the required time length;

[0023] During the experiment, each single exposure chamber in the triplex exposure chamber set works independently between each other;

[0024] The dilution air flow F-AIR and the exposure aerosol flow F-AER entering each single exposure cabin through synchronous control are controlled, the dilution air flow and the exhaust flow are accurately adjusted, and the flow of the inhaled field exposure gas (or aerosol) is accurately controlled, so that the gradient exposure poisoning experiment of low, medium and high concentrations is simultaneously realized.

[0025] S4, the field synchronous experiment device is stored

[0026] After the experiment is completed, the gas connection pipe connected with each component is removed, each component is placed back to the original place of the main portable box and the auxiliary portable box, the upper cover of the main portable box and the auxiliary portable box is buckled, and then each component is safely and portably transported to the next experiment field, the steps S1-S4 are repeated, and a new animal exposure poisoning experiment is carried out.

[0027] The field synchronous experiment device for animal atmospheric poisoning exposure or the field synchronous experiment method for animal atmospheric poisoning exposure has the application in the atmospheric poisoning exposure toxicity evaluation and the rapid health risk assessment of atmospheric environmental pollution.

[0028] Compared with the prior art, the field synchronous experiment device for animal atmospheric poisoning exposure has the following advantages and effects:

[0029] 1. The field synchronous experiment device for animal atmospheric poisoning exposure provided by the present application is modular and lightweight, has small volume and simple pipeline, and is designed to be contained and carried in a fixed box body.

[0030] 2. The experiment device of the present application adopts a portable structure design, that is, the entire experiment device is placed in two portable instrument boxes, which can be flexibly carried to various environmental sites and can carry out animal exposure poisoning experiments at any time.

[0031] 3、The experimental device and method provided by the application can be combined with each other, can carry out toxicity evaluation experiments of multiple concentration conditions of ambient air at the same time under more real experimental conditions, the aerosol component distribution consistency of the exposure experiment is very high, the experimental data is more real, effective and comparable, and the multiple needs of the rapid health risk assessment research of the actual pollution environment for field experimental data are well solved; the application can also consider the simulation experiment or sampling experiment in the laboratory, one machine with two functions, through simulating the real exposure scene (such as air pollution) of the environmental event in the laboratory, through the precise control of multiple concentrations and multiple gradients, the experimental data obtained can also have more extrapolation value, can be applied to more research fields, and the comprehensive utilization rate of the equipment is improved. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 The structure diagram of the whole storage of the on-site synchronous experimental device for animal atmospheric toxic exposure of the embodiment of the application and the unfolding of the upper cover is shown.

[0033] Figure 2 The top view structure diagram of the on-site synchronous experimental device for animal atmospheric toxic exposure of the embodiment of the application is shown.

[0034] Figure 3 The three-dimensional appearance structure diagram of the triple exposure cabin suite in the embodiment of the application is shown.

[0035] Figure 4 The front view structure diagram of the triple exposure cabin suite in the embodiment of the application is shown.

[0036] Figure 5 The top view structure diagram of the triple exposure cabin suite in the embodiment of the application is shown.

[0037] Figure 6 The three-dimensional structure diagram of the triple exposure cabin suite in the embodiment of the application after the transparent upper cover is opened is shown.

[0038] Figure 7 The working principle diagram of the single exposure cabin room passage connection structure and aerosol flow in the embodiment of the application is shown.

[0039] Figure 8 The assembly structure diagram of the single exposure cabin room passage connection in the embodiment of the application (omitting the gas supply connection pipe) is shown.

[0040] Reference signs:

[0041] 1, main portable box; 1a, main portable box upper cover; 1b, main portable box body; 2, auxiliary portable box; 2a, auxiliary portable box upper cover; 2b, auxiliary portable box body; 5, triplex exposure cabin set; 6, air extraction filter; 7, air extraction mass flow controller; 8, dilution air mass flow controller; 9, dilution air filter; 10, direct current mobile power supply; 11, positive pressure air pump; 12, negative pressure air pump; 13, cylindrical transparent shell; 14, circular transparent upper cover; 15, transparent base; 16, exposure chamber horn-shaped top cover; 17, aerosol four-way distributor connecting elbow; 18, concentration dilution gas introduction pipe; 19, four-way aerosol distributor; 20, four-way distributor aerosol inlet; 21, bottom waste gas exhaust pipe; 22, air inlet; 23, sealing ring; 24, gas conveying connecting pipe; 27, simplex exposure cabin. DETAILED DESCRIPTION

[0042] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions of the present application are further described in detail below in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in each embodiment of the present application described below can be combined with each other as long as they do not conflict with each other.

[0043] Embodiment 1

[0044] Referring to the drawings, Figures 1-8 the general-purpose animal atmospheric exposure synchronous experimental device provided by the embodiment of the present application includes a main portable box 1 and an exposure experimental unit which are modularly designed and detachably connected, an auxiliary portable box 2 and an experimental support unit;

[0045] Each component of the exposure experimental unit is arranged in the main portable box 1, including:

[0046] Triplex exposure cabin set 5, air extraction filter 6, air extraction mass flow controller 7, dilution air mass flow controller 8, dilution air filter 9;

[0047] Each component of the experimental support unit is arranged in the auxiliary portable box 2, specifically arranged in each groove of the foam support pad in the auxiliary portable box 2, including:

[0048] Direct current mobile power supply 10, positive pressure air pump 11, negative pressure air pump 12 (vacuum pump);

[0049] The main portable box 1 and the exposure experiment unit, the secondary portable box 2 and the experiment support unit are simultaneously carried to the site, the components are connected to each other through the gas supply connection pipe 24, the on-site synchronous experiment device for atmospheric exposure of animals is formed, and the environmental event on-site atmospheric exposure experiment is directly carried out.

[0050] The main portable box 1 includes a square box type main portable box body 1b and a main portable box upper cover 1a which are buckled to each other, and the components of the exposure experiment unit are specifically arranged in the grooves of the foam support pad of the main portable box body 1b.

[0051] The secondary portable box 2 includes a secondary portable box body upper cover 2a and a secondary portable box body 2b, and the components of the experiment support unit are specifically arranged in the grooves of the foam support pad of the secondary portable box body 2b.

[0052] Both the box bodies can adopt the corner reinforcement and anti-collision design of an aviation box.

[0053] The triple exposure cabin set 5, the air extraction mass flow controller 7, the dilution air mass flow controller 8, the air extraction filter 6 and the dilution air filter 9 are randomly embedded in the foam support pad of the main portable box body 1b; when the main portable box body 1b and the main portable box upper cover 1a are buckled, the components are accommodated and fixed in the main portable box 1, can be integrally carried, and are convenient to take out and put in.

[0054] The triple exposure cabin set 5 is integrally installed and used (the components are connected between each other when the set is manufactured, and the set is integrally taken out and connected to other components through a pipeline when used), and includes the following components which are pre-installed: a circular transparent upper cover 14, a cylindrical transparent shell 13, a transparent base 15, an exposure chamber horn-shaped top cover 16, a single exposure cabin 27, an aerosol four-way distributor 19, an aerosol four-way distributor connecting elbow 17, a concentration dilution gas introduction pipe 18 connecting the single exposure cabin, and a bottom waste gas exhaust pipe 21.

[0055] The overall shape of the triple exposure cabin kit 5 is a cylindrical sealed box structure with an inner hollow, a base at the bottom and a cover at the top, and each part is made of transparent plastic injection molding for observation. The inner hollow part is surrounded by a circular transparent cover 14, a cylindrical transparent shell 13 and a transparent base 15. In the space of the inner hollow part, three cylindrical single exposure cabin chambers 27 with the same diameter and height are arranged in a central symmetric and vertical manner. Each single exposure cabin chamber 27 is provided with an upper opening and a lower exhaust gas discharge hole, and the internal space of each single exposure cabin chamber 27 is independent. The three single exposure cabin chambers 27 divide the inner hollow space of the triple exposure cabin kit 5 equally. The top of the upper opening of each single exposure cabin chamber 27 is provided with an exposure chamber horn-shaped top cover 16 opening downward (the horn mouth points downward), the bottom surface of each exposure chamber horn-shaped top cover 16 is connected with the top surface of the single exposure cabin chamber 27, and the top of each exposure chamber horn-shaped top cover 16 is fixedly arranged on the inner side surface of the circular transparent cover 14. The top of the exposure chamber horn-shaped top cover 16 is also provided with an air inlet 22 leading to the single exposure cabin chamber 27, which penetrates the circular transparent cover 14 (penetrates the thickness of the circular transparent cover 14 to reach its upper surface) and is connected with the aerosol four-way distributor connecting elbow 17.

[0056] On the top surface of each single exposure cabin chamber 27, a top sealing ring 23 is arranged. The top surface of each single exposure cabin chamber 27 is connected with the horn mouth of the exposure chamber horn-shaped top cover 16 through the top sealing ring 23, so as to seal the internal space of each single exposure cabin chamber 27.

[0057] The four-way aerosol distributor 19 is provided with an opening at the center position, that is, a four-way distributor aerosol inlet 20, which serves as a total inlet for environmental air or aerosol.

[0058] The other end of the three aerosol four-way distributor connecting elbows 17 is connected with the circular transparent cover 14, and the corresponding horn mouth position of each exposure chamber horn-shaped top cover 16 is provided with a through hole, so as to connect the four-way aerosol distributor 19 with the internal space of the exposure chamber horn-shaped top cover 16 and the single exposure cabin chamber 27, and form three synchronous and independent exposure cabin pipelines.

[0059] A concentration dilution gas guide pipe 18 is arranged on the middle segment of each of the three aerosol four-way distributor connecting elbows 17. The concentration dilution gas guide pipe 18 first guides the concentration dilution gas entering each single exposure cabin chamber 27 into the aerosol four-way distributor connecting elbow 17, and then enters each single exposure cabin chamber 27 together with the external exposure gas, so as to adjust the exposure concentration in each single exposure cabin chamber 27.

[0060] The three exposure experiment units of the exhaust filter 6, the exhaust mass flow controller 7 (referred to as the exhaust MFC), the dilution air mass flow controller 8 (referred to as the dilution air MFC), and the dilution air filter 9 are all provided with three, which are respectively connected with the positive pressure air pump 11, the negative pressure air pump 12, and the pipeline of each single exposure cabin in the three-in-one exposure cabin suite 5 through the air conveying connecting pipe 24 to form a three-in-one synchronous experimental device for animal atmospheric pollution exposure.

[0061] In the embodiment, the three-in-one exposure cabin suite 5 includes three transparent cylindrical single exposure cabin rooms 27, which are arranged in a three-equal-circumferential-symmetrical radial structure layout in a large circular exposure cabin transparent shell (referred to as the shell); the circular transparent upper cover 14 also has three exposure room horn-shaped top covers 16 arranged in a three-equal-circumferential-symmetrical radial structure layout, each top cover 16 corresponding to a lower cylindrical single exposure cabin room 27; when the circular transparent upper cover 14 is placed on the shell, the exposure room horn-shaped top cover 16 and the single exposure cabin room 27 are both in the circular exposure cabin transparent shell; the sealing ring 23 arranged at the top of the single exposure cabin room 27 is in butt joint with the exposure room horn-shaped top cover 16 of the single exposure cabin room 27, and a planar seal is formed at the interface; the central hole at the top of the exposure room horn-shaped top cover 16 is the exposure cabin air inlet 22, and a hole (waste gas discharge interface) is arranged at the center of the bottom of the single exposure cabin room 27 to connect the exposure room waste gas discharge pipe 21. Above each single exposure cabin room 27, the center of each circular transparent upper cover 14 (the center of the center of the three center transparent upper covers), a four-way aerosol distributor 19 (four-way gas distributor) is arranged, and a through hole (i.e. four-way distributor aerosol inlet 20) is vertically arranged at the center of the vertex of the four-way gas distributor as a total inlet for environmental air or aerosol; the four-way distributor aerosol inlet 20 is specifically composed of three-equal-symmetrical holes (three side wall holes) arranged in the inner side wall of the four-way aerosol distributor 19, each side wall hole is connected to each exposure room horn-shaped top cover 16 and single exposure cabin room 27 by an aerosol distributor connecting elbow pipe 17 (referred to as the elbow pipe) with the same structure; one end of the elbow pipe 17 is connected to a side wall hole, and the other end is connected to the central hole of the exposure room horn-shaped top cover 16, that is, the top air inlet 22 (or aerosol inlet) of each exposure cabin room; a concentration dilution gas introduction pipe 18 (connecting pipe) is also connected upward in the vertical direction of the middle section of each elbow pipe 17. In use, the circular transparent upper cover 14 together with the exposure room horn-shaped top cover 16 can be temporarily removed, and the experimental animals are placed into the single exposure cabin room 27 and then put back; all pipelines are made of transparent plastic material for easy connection and observation.

[0062] A synchronous experimental method for animal atmospheric pollution exposure in situ, comprising the following steps:

[0063] S1, preparation of the synchronous experimental device in situ

[0064] The main portable box 1 and the exposure experiment unit, the secondary portable box 2 and the experiment support unit of the on-site synchronous experiment device for the atmospheric exposure of animals are carried to the experimental site;

[0065] The upper cover of the main portable box 1 and the secondary portable box 2 is opened, and the components of the exposure experiment unit and the experiment support unit are taken out, and then the components are connected through the gas connection pipe 24 or electrically connected through the electric wire to form a triple exposure on-site synchronous experiment device for the atmospheric exposure of animals; specifically including:

[0066] S1-1 Exposure experiment unit: open the main portable box 1, open the upper cover, and take out each component from the main portable box body, and the triple exposure cabin set 5 is taken out as a whole;

[0067] S1-2 Experiment support unit preparation: open the upper cover of the secondary portable box 2, and take out each component from the secondary portable box body;

[0068] S1-3 Connection into a triple exposure on-site synchronous experiment device for the atmospheric exposure of animals

[0069] The DC mobile power supply 10 and the PLC controller are connected with the positive pressure air pump 11, the negative pressure air pump 12, the air extraction mass flow controller 7 and the dilution air mass flow controller 8 respectively to provide power or control signals;

[0070] The air inlet 22 of each single exposure cabin 27 in the triple exposure cabin set 5 is connected with the four-way aerosol distributor connection elbow 17 and the four-way aerosol distributor 19 through the aerosol four-way distributor, and is connected with the concentration dilution gas inlet pipe 18; the concentration dilution gas inlet pipe 18 is connected with the dilution air mass flow controller 8, the dilution air filter 9 and the positive pressure air pump 11 in sequence through the gas connection pipe 24 to form a closed air inlet pipeline;

[0071] The bottom exhaust pipe 21 of each single exposure cabin 27 in the triple exposure cabin set 5 is connected with the air extraction filter 6, the air extraction mass flow controller 7 and the negative pressure air pump 12 in sequence through the gas connection pipe 24 to form a closed exhaust pipeline;

[0072] The four-way distributor aerosol inlet 20 in the triple exposure cabin set 5 is connected with an external aerosol generator to synchronously input the same concentration of aerosol into each single exposure cabin 27;

[0073] After all the components are connected, there are three synchronous and independent exposure cabin air inlet and exhaust paths centered on the single exposure cabin 27 to form a triple exposure on-site synchronous experiment device for the atmospheric exposure of animals;

[0074] S1-4 power on, leak test

[0075] Power on each part, test the sealing performance of the air inlet and exhaust passage of each independent operating exposure chamber;

[0076] S2, preparation of on-site synchronous animal exposure experiment

[0077] Determine the exposure experiment scheme, including exposure dose, exposure process control, determine the control parameters of the animal exposure experiment; prepare experimental animals, experimental materials, etc. respectively; specifically including:

[0078] S2-1 Determine the exposure experiment scheme

[0079] According to the experimental purpose, the simulated scene and the expected results, determine the whole body exposure experiment scheme, including the type of experiment, experimental animals, experimental materials and equipment, determine the exposure dose, concentration gradient, exposure process control requirements, determine the control parameters of the animal exposure experiment, including the dilution air flow F-AIR and total exhaust flow F-EXH of each exposure chamber, other control parameters also include aerosol uniformity, dose accuracy and animal welfare, etc.

[0080] S2-2 Preparation of experimental supplies

[0081] Prepare experimental animals, experimental materials;

[0082] S2-3 Connection of each part

[0083] Connect each part of the on-site synchronous animal exposure experiment device for atmospheric exposure of animals through the air pipe respectively, to form an experimental system that can perform the whole body exposure experiment scheme on site.

[0084] S3, on-site synchronous animal exposure experiment

[0085] Open the circular transparent upper cover 14, divide the experimental animals into three groups of animals, corresponding to a single exposure chamber 27 of the triple exposure chamber for atmospheric exposure of animals on-site synchronous experimental device, and then put the circular transparent upper cover 14 back in place; control the operating parameters of each part of the triple exposure chamber for atmospheric exposure of animals on-site synchronous experimental device, perform triple synchronous exposure process control until the required time duration;

[0086] During the experiment, each single exposure chamber 27 in the triple exposure chamber set 5 works independently between each other;

[0087] The dilution air flow rate (F-AIR) and the exposure aerosol flow rate (F-AER) into each single-exposure chamber 27 are synchronously controlled, the dilution air flow rate and the exhaust flow rate are accurately adjusted, and the flow rate of the inhaled exposure gas is accurately controlled, so that the gradient exposure experiments of three concentrations are simultaneously performed synchronously; specifically including:

[0088] S3-1 According to the exposure experiment scheme, the experimental animals are divided into three groups of animals, which are loaded into one single-exposure chamber 27 of the three-in-one atmospheric exposure device for synchronous exposure experiments on site;

[0089] S3-2 Control the operating parameters of each part of the three-in-one atmospheric exposure device for synchronous exposure experiments on site, execute the exposure experiment scheme, and perform the three-in-one synchronous exposure process control until the required time duration; during the experiment, the single-exposure chambers 27 in the three-in-one exposure chamber set 5 work independently of each other;

[0090] According to the exposure dose determined by evaluation, the concentration gradient requirement is achieved by controlling the dilution air flow rate during the exposure experiment;

[0091] The dilution air flow rate and the exhaust flow rate in the air inlet and exhaust passages of the three independently operated exposure chambers are synchronously and accurately adjusted, the flow rate of the inhaled exposure gas (or aerosol) is accurately controlled, the accurate concentration dilution control is achieved, the gradient experiments of three concentrations are simultaneously performed, and the comparability of the experimental data is improved. By synchronously controlling the dilution air flow rate F-AIR and the total exhaust gas flow rate (F-EXH, referred to as total exhaust flow rate) into each single-exposure chamber 27, the flow rate F-AER and the concentration of the inhaled exposure gas in each single-exposure chamber 27 are indirectly controlled. By accurately adjusting the dilution air flow rate and the total exhaust flow rate F-EXH in the three pipeline channels, the flow rate of the inhaled exposure gas (or aerosol) in each single-exposure chamber 27 can be accurately controlled, the exposure dose and the concentration can be controlled, and the gradient exposure experiments of three different concentrations can be simultaneously performed synchronously; the calculation formula of the exposure concentration is: F-AER / (F-EXH). Specifically,

[0092] The positive pressure air pump 11 sequentially passes through the air conveying connection pipe 24, the dilution air filter 9, the dilution air mass flow controller 8 (MFC), the concentration dilution gas introduction pipe 18 connected to each single-exposure chamber, and the corresponding single-exposure chamber 27, to form an air inlet passage;

[0093] The clean air enters into each single exposure cabin 27 through the air inlet passage: the clean air is sucked from the positive pressure air pump 11, pressurized, sequentially passes through the dilution air filter 9, the dilution air mass flow controller 8 (dilution air MFC), the air conveying connecting pipe 24, the concentration dilution gas introduction pipe 18 connecting each single exposure cabin, and enters into each single exposure cabin 27, and the flow rate is F-AIR, which is controlled by the dilution air mass flow controller 8;

[0094] The single exposure cabin 27, the air exhaust filter 6 and the air exhaust mass flow controller 7 (air exhaust MFC) are connected with the negative pressure air pump 12 through the air conveying connecting pipe 24 to form an air exhaust passage;

[0095] The gas (exhaust gas) in the single exposure cabin 27 after exposure is exhausted to the exhaust gas treatment equipment or the atmosphere through the air exhaust passage, and the exhaust gas flow rate F-EXH (total exhaust flow rate) is controlled by the air exhaust mass flow controller 7;

[0096] The field external gas (field exposure gas or external aerosol) enters into (is sucked into) the internal space of the three single exposure cabins 27 through the four-way aerosol distributor 19 and the three aerosol four-way distributor connecting pipes 17, and is mixed with the clean air to obtain the required exposure concentration and exposure dose (when the concentration is high and the exposure dose is high, the flow rate of the clean air can be zero); the aerosol flow rate F-AER of the (field exposure gas) flowing through the three aerosol four-way distributor connecting pipes 17 is controlled by the dilution air flow rate F-AIR and the total exhaust flow rate F-EXH (the mixing ratio of the external gas and the clean air and the total amount of the mixed gas); the PLC controller controls the field exposure gas exposure concentration and exposure dose in the internal space of the three single exposure cabins 27 synchronously (including low concentration, medium concentration and high concentration in parallel) by controlling the dilution air flow rate F-AIR and the total exhaust flow rate F-EXH in the three independent air paths.

[0097] The biggest advantage of the embodiment of the present application in the control process is that the exposure gas (or further mixed with the detection aerosol) can be collected in the field, the dilution air flow rate F-AIR and the exposure aerosol flow rate F-AER of each exposure cabin are equal to the total exhaust flow rate F-EXH according to the formula F-AER = F-EXH - F-AIR, the exposure aerosol (field exposure gas) flow rate F-AER is accurately controlled by the cooperation of the two flow controllers, and the exposure dose and concentration in each exposure cabin can also be accurately controlled synchronously, and the exposure concentration = F-AER / (F-EXH) x 100%.

[0098] S3-3 In the exposure experiment process, the survival state of the animals is observed in time, the activity level and behavior change of the animals are observed, and the physiological indexes are monitored;

[0099] S3-4, sample collection and analysis, evaluation and analysis of the experimental monitoring data obtained from the three groups of experimental animals and the collected samples, including respiratory system evaluation, systemic toxicity analysis, particulate matter clearance kinetics analysis, and output of the corresponding analysis results.

[0100] S4, on-site synchronous experimental device storage

[0101] After the experiment is completed, the gas connection pipe 24 connecting the various components is removed, and the operation opposite to step S1 is performed to place the various components back to their original positions in the main portable box 1 and the auxiliary portable box 2, the upper cover of the portable box is buckled, and then the various components are safely and portably transported to the next experimental site, steps S1-S4 are repeated, and a new animal exposure experiment is carried out.

[0102] The animal atmospheric toxic exposure on-site synchronous experimental device or the animal atmospheric toxic exposure on-site synchronous experimental method can be applied in atmospheric toxic exposure toxicity evaluation and rapid health risk assessment of atmospheric environmental pollution, and high-time-efficiency and high-accuracy atmospheric toxic exposure toxicity evaluation and rapid health risk assessment of atmospheric environmental pollution can be performed by using the on-site experimental data and biological sample data obtained by the device or method.

[0103] The experimental device provided by the embodiment of the present application adopts a portable modular structure design, divides the entire experimental device into an exposure experiment unit and an experimental support unit, and places the units in a portable instrument box, so that the device can be flexibly carried (carried by vehicle) to various environmental event sites, and the animal exposure experiment can be quickly deployed and carried out, and then quickly removed. In order to more efficiently, quickly and accurately carry out toxicity evaluation, the device adopts a design of simultaneously performing different concentration exposure experiments by multiple exposure cabins (different exposure concentrations and exposure doses are obtained by introducing clean air with different flow rates to dilute the on-site exposure gas), and multiple concentration gradient experiments are carried out at the same time, so that the toxicity evaluation experiment can be completed in a shorter time. In order to ensure the consistency of the distribution of pollutants (or aerosol particle sizes in other embodiments) in the air in all concentration gradient experiment exposure cabins, the positions of the multiple exposure cabins are designed as a three-equal-part circumferentially symmetrical radial structure layout, and the aerosol inlets are shared, so that the volume is reduced and synchronous control is easy. The device and the method provided by the present application are combined, the toxicity evaluation experiment of environmental air under multiple concentration conditions can be carried out at any time on site at the same time under more real experimental conditions, the consistency of the distribution of the exposure experiment on-site air components is very high, the experimental data is more real and effective, and the problems of rapid completion of health risk assessment research in the actual pollution environment, and the accuracy and comparability of experimental data are well solved.

[0104] Embodiment 2

[0105] The animal atmospheric pollution exposure field synchronous experiment device, the experiment method and the application provided by the embodiment are based on the specific application of the embodiment 1, and provide an animal atmospheric pollution exposure field synchronous experiment device and method which can be specifically applied to the research on the influence of extremely heavy pollution weather on respiratory health. The animal atmospheric pollution exposure field synchronous experiment device further comprises an automatic control unit, and the automatic control unit comprises a PLC controller integrated in the direct current mobile power supply 10. The PLC controller is electrically connected with the air extraction mass flow controller 7, the dilution air mass flow controller 8, the direct current mobile power supply 10, the positive pressure air pump 11 and the negative pressure air pump 12, and the flow of the air extraction mass flow controller 7 and the dilution air mass flow controller 8 in the pipeline of each single exposure cabin is controlled to realize the accurate automatic control of the exposure concentration of the field air (or aerosol).

[0106] Air pollution events are one of the hotspots in environmental research in recent years. The embodiment is aimed at the characteristics of air pollution events, such as regionality, complexity of composition, variability and instability of state. At present, the research methods mainly include composition source analysis and laboratory simulation of pollutant exposure experiment. The experimental data obtained by these methods often lack authenticity. The animal atmospheric pollution exposure field synchronous experiment device and method provided by the embodiment 1 can be carried to the most seriously polluted area according to the meteorological analysis and forecast, and the device can be used to carry out real exposure experiments on three groups of animals in a very short time by taking the field air as the exposure object, putting the experimental animals into three exposure cabins and controlling the concentration of each exposure cabin. The device can obtain field exposure experimental data and biological samples. According to the physiological and pathological analysis of the exposure data and the experimental animal samples and the molecular biology analysis, the evaluation results of the influence of real pollutants on respiratory health can be obtained.

[0107] The embodiment fully utilizes the characteristics of the field synchronous experiment device, such as portability, mobility, rapidness and high efficiency. The device can directly take the polluted air as the exposure research object, carry out flight detection at different times (seasons) and different places, and then take the experimental animals or samples back to the laboratory for specific analysis. The device can conveniently carry out exposure experiments at multiple time points and multiple places, obtain real data in the field, and then be used for comparative research on various environmental pollutions.

[0108] The animal atmospheric pollution exposure field synchronous experiment device adopted in the embodiment is the same as that in the embodiment 1, and the difference lies in that the animal atmospheric pollution exposure field synchronous experiment method further comprises the following steps on the basis of the embodiment 1.

[0109] An animal atmospheric pollution exposure field synchronous experiment method, which is based on the embodiment 1 and comprises the following different steps.

[0110] S1-2 Experimental support unit preparation: open the upper cover of the auxiliary portable box 2, take out each component from the auxiliary portable box body, and take out the DC mobile power supply 10 and the PLC controller as a whole;

[0111] S1-3 Connect the on-site synchronous experimental device for three-unit animal atmospheric exposure

[0112] Connect the DC mobile power supply 10 and the PLC controller to the positive pressure air pump 11, the negative pressure air pump 12, the air extraction mass flow controller 7, and the dilution air mass flow controller 8, respectively, to provide power or control signals;

[0113] S2, preparation of on-site synchronous animal exposure experiment

[0114] According to the experimental purpose, the simulated scene and the expected result, determine the whole body exposure experiment scheme, including the experimental type, the experimental animal, the experimental material and the equipment, determine the exposure dose, the concentration gradient, the exposure process control requirement, determine the control parameters of the animal exposure experiment, including the dilution air flow F-AIR and the total exhaust flow F-EXH of each exposure cabin, and input the PLC controller; other control parameters also include aerosol uniformity, dose accuracy and animal welfare, etc.;

[0115] S2-3 Connection of each part

[0116] Connect each part of the on-site synchronous experimental device for animal atmospheric exposure through the air supply pipeline, and electrically connect the air extraction mass flow controller 7, the dilution air mass flow controller 8, the positive pressure air pump 11, and the negative pressure air pump 12 to the PLC controller, respectively, to form an experimental system that can execute the whole body exposure experiment scheme on site;

[0117] S3, on-site synchronous animal exposure experiment

[0118] Divide the experimental animals into three groups of animals, corresponding to the single-unit exposure cabin 27 in the three-unit animal atmospheric exposure on-site synchronous experimental device, and control the operation parameters of each part of the three-unit animal atmospheric exposure on-site synchronous experimental device by the PLC controller to perform three-unit synchronous exposure process control until the required time duration;

[0119] During the experiment, each single-unit exposure cabin 27 in the three-unit exposure cabin set 5 works independently between each unit;

[0120] The PLC controller synchronously controls the dilution air flow F-AIR and the exposure aerosol flow F-AER into each single-exposure chamber 27, accurately adjusts the dilution air flow and the exhaust flow, and then accurately controls the flow of inhaled aerosol, thereby synchronously achieving the gradient exposure experiments of three concentrations at the same time; specifically including:

[0121] S3-1 According to the exposure experiment scheme, the experimental animals are divided into three groups of animals, which are loaded into one single-exposure chamber 27 of the three-in-one atmospheric exposure device for synchronous on-site experiment.

[0122] S3-2 The PLC controller controls the operating parameters of each part of the three-in-one atmospheric exposure device for synchronous on-site experiment, executes the exposure experiment scheme, and performs the three-in-one synchronous exposure process control until the required time duration; during the experiment, the single-exposure chambers 27 in the three-in-one exposure chamber set 5 work independently of each other.

[0123] According to the exposure dose determined by the evaluation, the concentration gradient requirement is achieved by controlling the dilution air flow during the exposure process.

[0124] The PLC controller synchronously and accurately adjusts the dilution air flow and the exhaust flow in the air inlet and exhaust passages of the three independently operated exposure chambers, accurately controls the flow of inhaled aerosol, achieves accurate concentration dilution control, and simultaneously performs gradient experiments of three concentrations to improve the comparability of experimental data.

[0125] The PLC controller synchronously controls the dilution air flow F-AIR and the total exhaust flow F-EXH into each single-exposure chamber 27 through two MFCs, indirectly controls the exposure aerosol flow F-AER and the concentration inhaled into each single-exposure chamber 27, and accurately adjusts the dilution air flow and the total exhaust flow F-EXH in the three pipeline channels, thereby accurately controlling the exposure air flow (or aerosol flow), exposure dose, and concentration of external atmosphere inhaled into each single-exposure chamber 27, and synchronously achieving the gradient exposure experiments of three different concentrations at the same time. More specifically:

[0126] (I) Research design and preparation

[0127] 1. Selection of research subjects: Healthy C57BL / 6J mice are selected as model animals. In some cases, specific disease model animals (such as asthma and COPD models) can also be selected to evaluate the impact of pollution on existing respiratory diseases.

[0128] 2. Animal experiment ethics approval: Before starting the experiment, it is necessary to pass the animal experiment ethics committee approval to ensure that the experiment meets the ethical requirements and minimizes the suffering of animals. It is necessary to clarify the exposure concentration, exposure time, etc., and to preset the health monitoring and emergency plan of the animals during the experiment.

[0129] 3. Exposure condition design

[0130] Pollutant selection: According to the characteristics of extremely heavy pollution weather, common pollutants such as PM 2.5 , PM 10 , NO2, SO2, O3, etc. are selected.

[0131] Exposure concentration and duration design: These exposure conditions should be selected as much as possible in extremely heavy pollution weather environment. For example, the concentration of PM 2.5 may reach more than 100 μg / m³, NO2 may reach 50-100 ppb, and the concentration of O3 may also be high.

[0132] Short-term exposure: The exposure time is usually several hours to several days, and the acute response (such as lung inflammation, acute respiratory response, etc.) is studied.

[0133] Long-term exposure: Exposure lasts for several weeks to several months to observe the health effects under long-term chronic exposure, such as airway remodeling, formation of chronic respiratory diseases, etc.

[0134] (II) Construction of animal exposure experiment system

[0135] In order to facilitate rapid movement and provide suitable temperature conditions for animals, two portable boxes are placed in a mini van, and are transported together to the environmental event site, and the exposure experiment system is formed by taking out and connecting the devices in the car, and after completion, the devices are disassembled and returned, and the whole is transported out; The whole process does not need to carry the device out of the car.

[0136] The operation steps of connecting and testing the field synchronous experiment device are as follows: the field synchronous experiment device for portable animal atmospheric toxic exposure of Example 1 is transported to the site of environmental events such as extremely heavy pollution weather, then the main and auxiliary portable boxes, auxiliary portable boxes are taken out, and each part is connected by gas connection pipe or wire, first assembled into the working state shown in Figure 7 , (single gas channel, single exposure chamber), then the other two gas channels and exposure chambers are also connected in the same way to form a three-channel, three-exposure chamber, and a synchronous working layout with the same exposure gas inlet, forming a three-in-one animal atmospheric toxic exposure field synchronous experiment device, directly using the external field pollution air as the exposure research object, and conducting power-on and sealing test on site to verify that each part can meet the experimental requirements, then enter the field synchronous experiment step.

[0137] (Three) experimental preparation

[0138] a. Determine the target and hypothesis of the experiment: clarify the target of the experiment, which is specifically the main toxic substances in the air on the scene of environmental events such as extremely heavy pollution weather, evaluate the acute / chronic toxicity of a certain toxicant, the impact on a certain organ, etc., determine the control variables, experimental groups and control groups in the experimental design;

[0139] b. Animal grouping: randomly divide the experimental animals (mice) into different groups, usually including different concentrations of experimental groups and control groups; the control group is not exposed to toxicants, and the experimental group is exposed to toxicants. This example uses SPF level animals raised in the animal room as the control group, and the experimental group is divided into at least three concentration gradient groups, including low concentration group, medium concentration group and high concentration group; the three groups of animals are correspondingly loaded into three single exposure chambers 27 distributed radially and centrally symmetrically, and the exposure experiment is carried out synchronously using independent air inlet and outlet pipelines and control steps for each;

[0140] (Four) Exposure experiment steps

[0141] a. Determine the exposure dose: preliminarily evaluate and determine the exposure dose according to the composition and distribution of toxicants in the air on the scene of environmental accidents such as extremely heavy pollution weather; the specific exposure dose includes LD50, NOAEL (no observable adverse effect level), etc., and this time the exposure experiment is carried out in an acute exposure mode;

[0142] b. Exposure experiment process control: according to the preliminary evaluation of the exposure dose, the concentration gradient requirement (divided into high, medium and low concentration gradients) needs to be achieved through dilution air flow control during the exposure experiment, and each part is automatically operated through the PLC controller until the set experimental time is reached; the PLC controller precisely adjusts the dilution air flow and exhaust flow in the air inlet and outlet passages of the three independently operated exposure chambers to accurately control the flow of inhaled aerosols, achieve precise concentration dilution control, and simultaneously perform three concentration gradient experiments to improve the comparability of experimental data;

[0143] c. After carrying the portable on-site synchronous experimental device to the desired location, place the experimental animals according to the pre-grouping number in the three different exposure chambers, set high, medium and low concentrations for the three exposure chambers through three mass flow controllers, open the sunroof of the mini van, start the negative pressure air pump and the positive pressure air pump, and the device starts to draw in the haze and other extremely heavy pollution air on the scene for real-time exposure experiment;

[0144] d. Real-time monitoring: during the exposure process, researchers need to monitor the concentration changes of pollutants in real time; and need to observe the survival state of animals at regular intervals, and if there is discomfort, immediately record the time and conduct further statistical analysis;

[0145] (5) Experimental data collection and sample analysis

[0146] a. Environmental data collection: During the exposure period, environmental data such as pollutant concentrations in the air, temperature and humidity, air pressure, etc. need to be collected in real time. These data provide background information for subsequent analysis of the impact of pollution exposure on respiratory health;

[0147] b. Physiological monitoring data collection: During the exposure experiment, physiological response indicators of animals are monitored and recorded, such as blood pressure, heart rate, respiration, etc. Animal activity levels, behavior changes, etc. should be monitored at any time, and if abnormal phenomena are found, they should be handled immediately;

[0148] c. Physiological response data collection can be obtained through lung function tests, airway resistance tests, alveolar function tests, etc. to obtain respiratory function data of animals after exposure;

[0149] d. Monitor the immune response of animals, for example, by detecting changes in inflammatory markers, immune cells (such as neutrophils, macrophages, etc.) in blood samples;

[0150] e. Lung tissue of animals can be analyzed pathologically after the experiment ends to observe inflammation, airway remodeling, fibrosis, etc. in the lungs;

[0151] f. Sampling time and sample collection:

[0152] Sampling is performed within 6-24 hours after acute exposure;

[0153] The types of samples collected include blood, urine, tissues (such as liver, kidney, lung, brain, etc.), feces, etc.

[0154] g. Histological analysis

[0155] Pathological examination (such as HE staining) and other biochemical analysis (such as immunohistochemistry, Western blot, PCR, etc.) are performed on the collected tissues to evaluate the damage and mechanism of the toxicant on the tissues;

[0156] h. Biochemical and molecular analysis

[0157] Biochemical tests are performed on blood and other biological samples, such as liver enzyme levels, kidney function indicators, etc., and molecular biology methods (such as gene expression analysis, protein expression detection, etc.) are used to further study the mechanism of action of the toxicant.

[0158] (6) Data analysis and result processing

[0159] a. Data statistics and analysis

[0160] Statistical analysis of experimental data is performed to assess differences between exposure and control groups, typically using t-tests, ANOVA, etc. Toxic effects can be assessed by parameters such as IC 50 , LD 50 , ED 50 , etc. Depending on the physiological data of the exposure and control groups, statistical analysis can be performed to compare the specific effects of different pollutant exposure concentrations and durations on animal health. For example, ANOVA, regression analysis, etc. can be used to analyze the relationship between pollutant concentration and respiratory health indicators.

[0161] b. Analysis of dose-response relationship: Through data analysis, the dose-response relationship between pollutant exposure concentration and exposure time and physiological response is studied, including observing changes in lung function of animals under different concentrations of PM 2.5 , NO2 or O3 exposure, and establishing a curve between concentration and physiological response.

[0162] c. Interpretation and summary of results

[0163] Based on experimental data, the toxic effects of the toxicant are interpreted, and existing research results are compared to summarize the possible mechanisms of action and potential risks to the organism.

[0164] (Seven) Health effect assessment

[0165] Short-term impact assessment: Assess the health effects after acute exposure, such as respiratory symptoms, short-term decline in lung function, inflammatory response (e.g. increased levels of inflammatory factors such as IL-6, TNF-α, etc.).

[0166] Long-term impact assessment: After long-term exposure, observe the occurrence of airway remodeling, chronic obstructive pulmonary disease (COPD), asthma and even early indicators of carcinogenic processes.

[0167] Immune response assessment: Analyze the impact of pollutants on the immune system of animals, especially the suppression or overactivation of respiratory immunity.

[0168] (Eight) Verification of assessment results

[0169] Control group comparison: By comparing with non-exposed or low concentration exposed groups, the health effects of pollution exposure are verified, especially the changes in respiratory health;

[0170] Long-term observation: Researchers can assess the impact of pollutants on long-term respiratory health by observing the health trends of animals after exposure over a long period of time;

[0171] Cross-species comparison: Compare the experimental results of animal models with human epidemiological data to assess the representativeness and applicability of animal models.

[0172] (IX) Ethics and Animal Welfare

[0173] Ethical Approval: As with any animal experiment, prior to conducting animal research using the portable exposure system, ethical committee approval must be obtained to ensure that the experiment complies with relevant ethical standards.

[0174] Experiment Monitoring: During the study, researchers need to regularly check the health of the animals and stop the experiment immediately and provide necessary medical treatment if discomfort occurs.

[0175] Animal Welfare: Ensure that animals are properly cared for during exposure to avoid excessive stress and suffering.

[0176] The on-site synchronous experimental device for animal atmospheric pollution exposure provided by the embodiment, the experimental method and the application can directly carry the on-site synchronous experimental device to the site with a van or the like, and can be quickly installed and used, so that the on-site synchronous experimental device can be used in respiratory health research in extremely heavy pollution weather, and can truly obtain the influence of on-site pollutant exposure on the respiratory system, and can deeply analyze the relationship between pollution exposure and health through accurate physiological monitoring. Through long-term and short-term exposure experiments, researchers can evaluate the effects of different pollutants on respiratory health, and provide scientific basis for formulating public health policies and air quality standards.

[0177] Compared with traditional laboratory simulation of pollutant aerosols, the embodiment has the following obvious advantages:

[0178] Real experimental environment: Direct exposure of animals in real pollution environment events on site can be operated under different climate and environmental conditions, providing more realistic exposure doses, so as to obtain more timely, externally effective and practical value experimental data and research results.

[0179] Flexibility and mobility: The portable design of the on-site synchronous experimental device makes it can be used in different places and different environments, especially suitable for field research in densely populated cities or heavily polluted areas. This device can be conveniently stored, installed and moved, and can directly expose research objects to real conditions in natural pollution environment, rather than limited to laboratory environment.

[0180] Ethics and control variable advantages: By using the portable on-site synchronous experimental device, researchers can monitor real specific variables (such as pollutant types and concentrations) in the actual exposure environment, making the research results more credible. During the exposure process, three concentration experiments can also be carried out by dilution to control environmental factors, and the experimental conditions have high repeatability. At the same time, compared with laboratory environment, the application of portable on-site synchronous experimental device and method can alleviate the ethical problems, especially in the research involving long-term exposure and health monitoring.

[0181] Embodiment 3

[0182] The animal atmospheric exposure synchronous experiment device, the experiment method and the application provided by the embodiment are based on the embodiments 1 and 2, and specifically provide a synchronous experiment device and method applied to the toxicity effect evaluation of toxic substances released in the air after chemical explosion.

[0183] In the chemical explosion site, volatile toxic chemicals (such as nitric acid, chlorine, organic compounds or dust aerosol substances, etc.) will quickly spread to form a high-concentration toxic gas cloud, which mainly causes multi-target damage to the respiratory tract, nervous system and liver of humans through respiratory tract inhalation and even skin exposure. In recent years, chemical explosion accidents have occurred frequently around the world, so it is very important to quickly evaluate the toxicity effect of toxic substances released in the air after chemical explosion. However, after the explosion, due to the fast diffusion speed of toxic substances and the complex concentration change, it is difficult to make effective and real rapid evaluation by using traditional exposure and poisoning equipment and methods.

[0184] The animal atmospheric exposure synchronous experiment device adopted in the embodiment is the same as that in the embodiment 1, and the difference lies in that the animal atmospheric exposure synchronous experiment method further includes the following steps based on the embodiments 1 or 2:

[0185] (I) Experimental background

[0186] Research purpose: to evaluate the acute toxicity effect of toxic gases (such as chlorine, ammonia or hydrogen sulfide) released after chemical explosion on animals, and to provide scientific basis for emergency response, public health protection and safety management.

[0187] Animal model selection: adult male SD rats (250-300 g) are selected, 10 rats per group, a total of 30 rats. Rats are sensitive to respiratory irritant gases and suitable for the study of various toxic gases.

[0188] (II) Exposure condition design

[0189] Exposure time: 30 minutes;

[0190] Concentration setting: 0 ppm (the control group can refer to the animals raised in the animal room), 100 ppm, 500 ppm, 1000 ppm (experimental group);

[0191] Exposure route: whole body exposure and poisoning (toxic gases mainly harm the respiratory tract, and may also have potential risks to the eyes and skin);

[0192] Environmental simulation: single ammonia gas is used to simulate the gas release in the exposure site in the laboratory.

[0193] (Three) Experimental equipment

[0194] The portable on-site synchronous experimental device needs to provide an exposure environment at the fire scene to ensure that experimental rats can come into contact with real smoke. To facilitate rapid movement and provide suitable temperature conditions for the animals, two portable boxes are placed in a mini van, which quickly transports them to the experimental site, conducts experiments, and quickly evacuates after completing the experiments.

[0195] (Four) Experimental process

[0196] After connecting the parts of the portable on-site synchronous experimental device, place it in the appropriate location at the explosion center, place the experimental animals according to the pre-grouped numbers in the three different exposure cabins, set the high, medium, and low concentrations for the three exposure cabins through three sets of mass flow controllers, open the vehicle sunroof, start the negative pressure air pump and positive pressure air pump to begin real-time exposure and poisoning experiments on the toxic air released after the explosion;

[0197] Continue to expose for 30 minutes, and record the rats' behavior (such as coughing, tearing) and respiratory rate during this period through monitoring equipment.

[0198] After the exposure is completed, transfer the surviving rats to a clean air environment and observe the mortality and recovery within 24 hours;

[0199] Real-time monitoring: During the exposure process, researchers monitor the concentration changes of pollutants in real time.

[0200] (Five) Specimen and data collection

[0201] Collect vital sign data: Record the mortality rate, time of onset of respiratory difficulty, and severity during the exposure period.

[0202] Collect histopathological specimen data: Autopsy the dead or surviving rats, collect lung, trachea, and nasal cavity samples, and make sections to observe pathological changes.

[0203] Collect biochemical index data: Detect interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in serum to evaluate the inflammatory response; measure blood pH to analyze acid-base balance.

[0204] (Six) Analysis of experimental content by sub-item

[0205] 1. Analysis of mortality and LC50

[0206] Mortality rate: 0 ppm: 0% (0 / 10);

[0207] 100 ppm: 0% (0 / 10);

[0208] 500 ppm: 60% (6 / 10);

[0209] 1000 ppm: 100% (10 / 10).

[0210] LC50 calculation: LC50 for 30 minutes exposure was about 450 ppm by Probit analysis, indicating that 50% of rats died at this concentration.

[0211] 2. Analysis of physiological and behavioral responses

[0212] 100 ppm: mild tearing and increased nasal discharge, slightly faster breathing, no deaths;

[0213] 500 ppm: severe wheezing, decreased movement, half of the rats died 20-30 minutes after exposure;

[0214] 1000 ppm: coma occurred within 15 minutes of exposure, all died within 30 minutes, accompanied by oral and nasal foam.

[0215] 3. Analysis of pathological and biochemical results

[0216] Lung and airway: 500 ppm: increased pulmonary edema, alveolar epithelial shedding, and inflammatory cell infiltration.

[0217] 1000 ppm: severe pulmonary hemorrhage, extensive necrosis of airway mucosa.

[0218] Nasal cavity: 500 ppm and above: nasal mucosa erosion, epithelial cell necrosis.

[0219] Biochemical indicators: IL-6 and TNF-α significantly increased above 100 ppm, indicating significant inflammatory response.

[0220] Blood pH decreased at 500 ppm and above (7.2-7.0), indicating metabolic acidosis.

[0221] (Seven) Analysis of results and applications

[0222] 1. Analysis of toxic effects

[0223] Ammonia in the toxic air released after the explosion, as a strong alkaline gas, stimulates and corrodes the respiratory tract by inhalation, causing acute pulmonary edema, inflammation, and acid-base imbalance. LC50 (450 ppm, 30 minutes) shows high toxicity, and the initial concentration on site (1000 ppm) is sufficient to be fatal in a short time.

[0224] 2. Practical application

[0225] Personal protection: In the area with concentration higher than 100 ppm, the rescue personnel should wear full-face respirator or positive pressure respirator, and the exposure time should be controlled within 15 minutes.

[0226] Evacuation range: The area with concentration higher than 500 ppm should be evacuated immediately, and the safety distance should be at least 1 km.

[0227] Medical emergency: The exposed person may have respiratory tract burns and pulmonary edema, and should be given oxygen and anti-inflammatory treatment immediately, and the blood pH should be monitored.

[0228] Environmental management: Ammonia is easily soluble in water, and it is recommended to use water mist to dilute the ammonia concentration in the air, while monitoring the water pollution.

[0229] In the embodiment of the application, the portable on-site synchronous experimental device can simultaneously perform exposure and poisoning experiments on three concentrations of toxic gases at a chemical explosion site. The embodiment successfully determines the acute inhalation toxicity (LC50 = 450 ppm, 30 minutes), and reveals the main toxicity mechanisms of the toxic air on respiratory tract corrosion, pulmonary edema and systemic inflammation. The research results of the embodiment can provide scientific basis for protection measures, evacuation plans and medical intervention after the explosion accident, and thus the irreplaceable role of the portable on-site synchronous experimental device in the toxicity evaluation of chemical explosion can be seen.

[0230] Based on the characteristics of flexibility, portability and direct use on site of the on-site synchronous experimental device and method, the embodiment adopts the method of simultaneously performing experiments at multiple gradient concentrations to complete the exposure experiment faster, which requires less time than traditional methods, so that it can be quickly deployed to the explosion site to quickly evaluate the toxicity of the environment and human after the chemical explosion. The time efficiency, authenticity and accuracy are stronger, and the tasks that cannot be completed by similar devices and methods can be completed.

[0231] Embodiment 4

[0232] The animal atmospheric poisoning exposure on-site synchronous experimental device, experimental method and application provided by the embodiment are based on embodiments 1 to 3, and specifically provide an animal atmospheric poisoning exposure on-site synchronous experimental device and method for rapid evaluation of the toxicity of smoke at a large fire site. The device and method are basically the same as embodiments 1 to 3, and the difference is that the exposure research object is smoke at a large fire site, and the obtained data and samples are applied to rapid evaluation of the toxicity of smoke at a large fire site.

[0233] Embodiment 5

[0234] The animal atmospheric toxic exposure field synchronous experiment device, the experimental method and the application provided by the embodiment are based on the embodiments 1 to 4, and specifically provide an animal atmospheric toxic exposure field synchronous experiment device and method for simulating field in a laboratory for rapid evaluation of various gas toxicities. The device and method are basically the same as those in the embodiments 1 to 4, and the difference lies in that the exposure research site is in the laboratory, and the auxiliary device and steps for field simulation need to be added accordingly. The auxiliary equipment includes scene simulation equipment, animal lung function detector, laser scanning confocal microscope and the like.

[0235] The animal atmospheric toxic exposure field synchronous experiment method is based on the embodiment 1, and on the basis of the main portable box 1 and the exposure experiment unit, the auxiliary device of the secondary portable box 2 and the experiment support unit in the field synchronous experiment device, the method further includes the following steps:

[0236] S2-1 determining the simulation field exposure experiment scheme

[0237] According to the experimental purpose, the simulated scene and the expected result, the whole body exposure toxic experiment scheme of the simulated field is determined, including the experimental type, the experimental animal, the experimental material and equipment, the exposure dose, the concentration gradient, the exposure process control requirement, the control parameter of the animal exposure toxic experiment, including the dilution air flow F-AIR and the total exhaust flow F-EXH of each exposure cabin, and other control parameters, which are input into the PLC controller;

[0238] S2-3 connecting each part

[0239] The animal atmospheric toxic exposure field synchronous experiment device, the aerosol generator, the real-time aerosol monitor and the auxiliary equipment are connected through the ventilation pipeline respectively, and are electrically connected with the PLC controller, so as to form an experimental system which can simulate a specific scene and execute the whole body exposure toxic experiment scheme.

[0240] Then, the steps S3-S4 are performed, the exposure experiment for rapid evaluation of various gas toxicities in the simulated field in the laboratory is completed, one machine with two uses of the device is realized, and the utilization rate of the equipment is improved.

[0241] In other embodiments, without the need to specially prepare external aerosol generators, real-time aerosol monitors and other auxiliary equipment, only two portable boxes and exposure experiment units, experiment support units and experimental animals are carried to the scene to directly carry out atmospheric exposure experiments.

[0242] The device and method provided by the above embodiments of the present application are based on the calculation formula that the dilution air flow (F-AIR) and the exposure aerosol flow (F-AER) in each exposure chamber are equal to the total exhaust flow (F-EXH) during operation. The exposure aerosol flow (F-AER) can be accurately controlled by controlling F-EXH minus F-AIR. Thus, the exposure dose and concentration (concentration=F-AER / (F-EXH)) can also be accurately controlled. The main operation control parameters are F-AIR and F-EXH flowing through each exposure chamber, which can be realized by the cooperation of the dilution air mass flow controller 8 and the exhaust mass flow controller 7. The control of the two mass flow controllers on the flow is automatic and high-precision control, and automatic operation. Therefore, the device and method provided by the embodiments of the present application can realize automatic control of different gradient concentrations through accurate control of the flow.

[0243] In addition, in the device and method provided by the above embodiments of the present application, long-term stable and high-reliability components (such as mass flow controllers, diaphragm vacuum pumps, etc.) are used, so that the failure rate of the device during portable disassembly, transportation and use is very low. In order to ensure that the equipment can be quickly and stably operated in the first time to carry out on-site acute exposure experiments in special environments, the key electrical parts are designed in a modular manner, which can be quickly and simply disassembled and conveniently replaced with spare parts, thereby ensuring that the experimental device and method can be successfully carried out at different sites at multiple times, multiple time points and multiple places.

[0244] It should be noted that in other embodiments of the present application, other different schemes obtained by specific selection within the scope of the structures, components, steps, process parameters, experimental conditions and applications disclosed in the present application can achieve the technical effects disclosed in the present application, and therefore the present application will not be listed one by one.

[0245] The above is only a preferred embodiment of the present application, and does not limit the present application in any form. Any person skilled in the art can make many possible changes and modifications to the technical solution of the present application, or modify it into equivalent embodiments without departing from the scope of the technical solution of the present application. Any equivalent changes made according to the components, ratio and process of the present application shall be covered within the protection scope of the present application.

Claims

1. An in situ, simultaneous experimental apparatus for atmospheric exposure of animals, characterized in that, It includes the main portable box (1) and exposure experiment unit of modular design and detachable connection, the secondary portable box (2) and experimental support unit; Wherein, each component of the exposure experiment unit is arranged in the main portable box (1), including: Triple exposure cabin suite (5), suction filter (6), suction mass flow controller (7), dilution air mass flow controller (8), dilution air filter (9); Each component of the experimental support unit is arranged in the secondary portable box (2), including: DC mobile power supply (10), positive pressure air pump (11), negative pressure air pump (12); When in use, the main portable box (1) and exposure experiment unit, the secondary portable box (2) and experimental support unit are carried to the scene at the same time, and each component is connected with each other through the gas conveying connecting pipe (24); Wherein, the suction filter (6), the suction mass flow controller (7), the dilution air mass flow controller (8) and the dilution air filter (9) of the exposure experiment unit are each provided with three, which are connected with each other through the gas conveying connecting pipe (24) after being connected with the pipeline of each single exposure cabin in the positive pressure air pump (11), the negative pressure air pump (12) and the triple exposure cabin suite (5), so as to form a scene synchronous experimental device for triple exposure of animals to atmospheric pollution, and environmental event atmospheric pollution exposure experiment can be directly carried out on the scene; The triple exposure cabin suite (5) includes: a circular transparent upper cover (14), a cylindrical transparent shell (13), a transparent base (15), an exposure chamber horn-shaped top cover (16), a single exposure cabin (27), an aerosol four-way distributor (19), an aerosol four-way distributor connecting elbow (17), a concentration dilution gas inlet pipe (18) connecting each single exposure cabin, and a bottom waste gas discharge pipe (21). The triple exposure cabin suite (5) is a cylindrical sealed box with an internal hollow, a base at the bottom and an upper cover at the top. The internal hollow part is surrounded by the circular transparent upper cover (14), the cylindrical transparent shell (13) and the transparent base (15). In the space of the internal hollow part, three cylindrical single exposure cabins (27) with the same diameter and height are vertically and centrally symmetrically arranged. Each single exposure cabin (27) is provided with an upper opening and a lower waste gas discharge hole, and the internal spaces of the single exposure cabins are independent of each other. The three single exposure cabins (27) equally divide the internal hollow space of the triple exposure cabin suite (5). The top of the upper opening of each single exposure cabin (27) is provided with an exposure chamber horn-shaped top cover (16) opening downward. The bottom surface of each exposure chamber horn-shaped top cover (16) is buckled with the top surface of the single exposure cabin (27), and the top of each exposure chamber horn-shaped top cover (16) is fixedly arranged on the inner side surface of the circular transparent upper cover (14). The exposure chamber horn-shaped top cover (16) is further provided with an air inlet (22) leading to the single exposure cabin (27). The air inlet (22) penetrates the circular transparent upper cover (14) and is connected with the aerosol four-way distributor connecting elbow (17). The aerosol four-way distributor (19) is provided with an opening in its center position, that is, a four-way distributor aerosol inlet (20), as a total inlet of ambient air or aerosol; one end of three aerosol four-way distributor connecting bends (17) is connected with the aerosol four-way distributor (19), and the other end is connected with a through hole arranged at a corresponding horn mouth position of each horn-shaped top cover (16) of the circular transparent upper cover (14), so as to communicate the aerosol four-way distributor (19) with the internal space of the exposed chamber horn-shaped top cover (16) and the single-connection exposed cabin (27), and form three synchronous and independent exposed cabin pipelines; The middle sections of the three aerosol four-way distributor connecting bends (17) are each provided with a concentration dilution gas introduction pipe (18), which introduces the concentration dilution gas entering each single-connection exposed cabin (27) into the aerosol four-way distributor connecting bend (17) and then into each single-connection exposed cabin (27), so as to adjust the exposure concentration in each single-connection exposed cabin (27).

2. The on-site synchronous animal exposure device according to claim 1, wherein the main portable box (1) comprises a square box-shaped main portable box body (1b) and a main portable box upper cover (1a) that are buckled to each other. The three-connection exposed cabin set (5), the air extraction mass flow controller (7), the dilution air mass flow controller (8), the air extraction filter (6), and the dilution air filter (9) are arranged in the main portable box body (1b) in a staggered manner; when the main portable box body (1b) and the main portable box upper cover (1a) are buckled, the aforementioned components are all accommodated and fixed in the main portable box (1), which can be carried as a whole and is convenient to take out and put in.

3. The on-site synchronous animal exposure device according to claim 1, wherein the device further comprises an automatic control unit, which comprises a PLC controller electrically connected with the air extraction mass flow controller (7), the dilution air mass flow controller (8), the direct-current mobile power supply (10), the positive pressure air pump (11), and the negative pressure air pump (12), so as to realize precise automatic control of the aerosol exposure concentration by adjusting the flow rates of the air extraction mass flow controller (7) and the dilution air mass flow controller (8) in each single-connection exposed cabin pipeline; and the PLC controller is integrated in the direct-current mobile power supply (10). The device comprises the following steps: S1, on-site synchronous device preparation: carrying the main portable box (1) and the exposure experiment unit, the auxiliary portable box (2) and the experiment support unit of the on-site synchronous animal exposure device according to any one of claims 1 to 3 to the experimental site; 4. A method for in situ, simultaneous experimentation of animal exposure to atmospheric pollution, characterized in that, opening the upper covers of the main portable box (1) and the auxiliary portable box (2), taking out the components of the exposure experiment unit and the experiment support unit, and connecting the components through the gas conveying connecting pipes (24) or electrically connecting the components through electric wires to form a three-connection animal exposure device; S2, on-site synchronous animal exposure experiment preparation: ​ ​ ​ Determine the exposure experiment scheme, including exposure dose, exposure process control, determine the control parameters of animal exposure to toxic experiment, prepare experimental animals; S3, on-site synchronous animal exposure to toxic experiment: Divide the experimental animals into three groups, corresponding to a single exposure chamber (27) of a three-in-one on-site synchronous experimental device for atmospheric toxic exposure of animals, control the operating parameters of each part of the three-in-one on-site synchronous experimental device for atmospheric toxic exposure of animals, perform three-in-one synchronous exposure process control, and continue until the required time length; During the experiment, each independent single exposure chamber (27) in the three-in-one exposure chamber set (5) works independently; Control the dilution air flow F-AIR and the exposure aerosol flow F-AER entering each single exposure chamber (27) through synchronous control, accurately adjust the dilution air flow and the exhaust flow, and then accurately control the flow of inhaled on-site exposure gas, to simultaneously achieve gradient exposure toxic experiment of low, medium and high concentrations; S4, on-site synchronous experimental device storage: After the experiment, remove the gas connection pipe (24) connecting each component, put each component back to its original place in the main portable box (1) and the auxiliary portable box (2), close the lid of the main portable box (1) and the auxiliary portable box (2), then safely and portably transport each component to the next experimental site, repeat steps S1-S4, and carry out new animal exposure toxic experiment.

5. The method of claim 4, wherein the method is performed in situ. The steps S1 include the following steps: S1-1 exposure experiment unit preparation: Open the main portable box (1), open the lid, and take out each component from the main portable box body, among which the three-in-one exposure chamber set (5) is taken out as a whole; S1-2 experimental support unit preparation: Open the lid of the auxiliary portable box (2), and take out each component from the auxiliary portable box body; S1-3 connection to a three-in-one on-site synchronous experimental device for atmospheric toxic exposure of animals: Connect the DC mobile power supply (10) with the positive pressure air pump (11), the negative pressure air pump (12), the air extraction mass flow controller (7), and the dilution air mass flow controller (8) respectively; Connect the air inlet (22) of each single exposure chamber (27) in the three-in-one exposure chamber set (5) with the aerosol four-way distributor connection elbow (17), the aerosol four-way distributor (19), and the concentration dilution gas inlet pipe (18); the concentration dilution gas inlet pipe (18) is connected with the dilution air mass flow controller (8), the dilution air filter (9), and the positive pressure air pump (11) in sequence through the gas connection pipe (24), forming a closed air inlet pipeline; Connect the bottom exhaust pipe (21) of each single exposure chamber (27) in the three-in-one exposure chamber set (5) with the air extraction filter (6), the air extraction mass flow controller (7), and the negative pressure air pump (12) in sequence through the gas connection pipe (24), forming a closed exhaust pipeline; Connect the four-way distributor aerosol inlet (20) of the three-in-one exposure chamber set (5) with the external on-site atmosphere to synchronously input the same concentration of on-site exposure gas into each single exposure chamber (27); After all the components are connected, there are three synchronized and independently operated air inlet and exhaust passages centered on the single-unit exposure chamber (27), forming a three-unit animal atmospheric toxic exposure field synchronous experimental device. S1-4 power on and sealing test: Power on each part and test the sealing performance of each independently operated air inlet and exhaust passage of the exposure chamber.

6. The method of claim 4, wherein the method is performed in situ. The step S2 includes the following steps: S2-1 determine the exposure experiment scheme: According to the experimental purpose, the simulated scene and the expected results, determine the whole-body exposure and toxic experiment scheme, including the experiment type, the experimental animals, the experimental materials and equipment, determine the exposure dose, the concentration gradient, the exposure process control requirements, determine the control parameters of the animal exposure and toxic experiment, including the dilution air flow F-AIR and the total exhaust flow F-EXH of each exposure chamber; S2-2 prepare experimental supplies: Prepare experimental animals and experimental substances; S2-3 connect each part: Connect each part of the animal atmospheric toxic exposure field synchronous experimental device through the air pipe, forming an experimental system that can perform whole-body exposure and toxic experiment scheme in the field.

7. The method of claim 4, wherein the method is performed in situ. The step S3 includes the following steps: S3-1 according to the exposure experiment scheme, divide the experimental animals into three groups, corresponding to the three-unit animal atmospheric toxic exposure field synchronous experimental device; S3-2 control the operating parameters of each part of the three-unit animal atmospheric toxic exposure field synchronous experimental device, execute the exposure experiment scheme, and perform three-unit synchronous exposure process control until the required time duration; During the experiment, each independent single-unit exposure chamber (27) in the three-unit exposure chamber set (5) works independently; According to the exposure meter determined by the evaluation, achieve the concentration gradient requirement by controlling the dilution air flow during the exposure and toxic process; By synchronously and accurately adjusting the dilution air flow and exhaust flow in the three independently operated air inlet and exhaust passages of the exposure chamber, the flow of air inhaled into the field is accurately controlled, the concentration dilution control is accurately controlled, the gradient experiment of low, medium and high concentration is simultaneously performed, and the comparability of experimental data is improved; S3-3 during the exposure experiment, observe the survival state of the animals, observe the activity level and behavior change of the animals, and monitor the physiological indicators; S3-4 sample collection and analysis, evaluate and analyze the experimental monitoring data obtained by the three groups of experimental animals and the collected samples, including respiratory system evaluation, whole-body toxicity analysis, and particle clearance kinetics analysis, and output the corresponding analysis results.

8. The animal atmospheric toxic exposure field synchronous experimental device of any one of claims 1 to 3, applied in atmospheric toxic exposure toxicity evaluation and rapid health risk assessment of atmospheric environmental pollution.

9. The animal atmospheric toxic exposure field synchronous experimental method of any one of claims 4 to 7, applied in atmospheric toxic exposure toxicity evaluation and rapid health risk assessment of atmospheric environmental pollution.

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