Method for determining exposure concentration in dynamic inhalation toxicity test of pyrethroid disc-type mosquito coil

Abstract

The present application belongs to the field of mosquito incense dynamic inhalation toxicity test, specifically to a method for determining the exposure concentration of pyrethroid disc-type mosquito incense dynamic inhalation toxicity test, comprising the following steps: 1) taking a mosquito incense of a set weight, igniting it, and collecting three smoke liquid samples through a generating and sampling device; 2) placing the three smoke liquid samples collected by the sampling device into separate volumetric flasks for processing, obtaining the processed smoke liquid samples, mixing them in a same sample flask, and measuring the pyrethroid mass in the smoke according to gas chromatography; 3) obtaining the conversion rate of the pyrethroid disc-type mosquito incense according to the obtained pyrethroid mass in the smoke and the mass of the disc-type mosquito incense; and 4) obtaining the exposure concentration of the pyrethroid disc-type mosquito incense according to the obtained pyrethroid mass in the smoke, the sampling volume of the sampling device, and the conversion rate. The processing and determination method of the present application lays a foundation for determining the exposure dose of pyrethroid disc-type mosquito incense dynamic inhalation toxicity.

Description

Technical Field

[0001] This invention belongs to the field of dynamic inhalation toxicity testing of mosquito coils, specifically a method for determining the exposure concentration of pyrethroid disc mosquito coils in dynamic inhalation toxicity testing. Background Technology

[0002] Pyrethroids are pesticides recommended by the World Health Organization for the control of sanitary pests. They have a strong contact toxicity to insects and can disrupt the nervous system of mosquitoes, causing them to die. The content of pyrethroids in mosquito coils is very low, and their toxicity to humans is not high. However, the harmful components and ultrafine particles in mosquito coil smoke can enter and remain in the lungs, endangering human health. Before mosquito coils are put into production, toxicological tests must be conducted to ensure safety and obtain a pesticide registration number from the agricultural department. Inhalation toxicity testing is one of the most important toxicological tests. Tests are conducted on rats after inhaling the smoke produced by burning mosquito coils to evaluate their inhalation toxicity.

[0003] Toxic dose, or exposure dose, is expressed as the mass of the mosquito coil. Because the entire inhalation exposure process is dynamic—requiring continuous removal of fumes and introduction of air to maintain a stable concentration within the coil—the mass of the burning mosquito coil cannot be simply used as the actual exposure dose. Techniques for evaluating the inhalation toxicity of mosquito coils are still lacking; therefore, it is imperative to develop a method for determining the exposure dose in dynamic inhalation toxicity tests of pyrethroid mosquito coils. Summary of the Invention

[0004] The purpose of this invention is to provide a method for determining the pyrethroid content in the smoke produced after burning a certain amount of mosquito coil using gas chromatography, and calculating the mass ratio (R%) of pyrethroids in the smoke to the mosquito coil, i.e., the conversion rate. Then, by measuring the pyrethroid content in the smoke after burning a mosquito coil in a poison canister, and then calculating the mass of the mosquito coil using the conversion rate, the exposure dose for inhalation toxicity testing can be calculated, thus overcoming the gap in the aforementioned methods for determining exposure dose.

[0005] The technical solution adopted by this invention to achieve the above objective is: a method for determining the exposure concentration of pyrethroid mosquito coils in a dynamic inhalation toxicity test, comprising the following steps:

[0006] 1) After igniting a set weight of pyrethroid-based mosquito coil, collect three samples of smoke liquid using a generator and sampling device;

[0007] 2) The three flue gas liquid samples collected by the generator and sampling device were placed into volumetric flasks for processing. The processed flue gas liquid samples were then mixed in the same injection bottle. After being mixed evenly, the mass of pyrethroids in the flue gas was measured by gas chromatography.

[0008] 3) Based on the mass of pyrethroids in the flue gas and the sampling volume of the generator and sampling device, the conversion rate of pyrethroid-based mosquito coils is obtained; and based on the obtained conversion rate of pyrethroid-based mosquito coils, the exposure concentration of pyrethroid-based mosquito coils is obtained.

[0009] The generating and sampling device includes: a triangular flask, an absorption tube, and an air pump connected in sequence;

[0010] The triangular bottle is used to hold burning pyrethroid-based mosquito coils.

[0011] The triangular bottle has an air inlet on its side to supply air to support the burning of the mosquito coil; the top of the triangular bottle is sealed and has a sampling port, which is connected to the absorption tube.

[0012] The inlet pipe of the absorption tube is connected to the sampling port to collect flue gas liquid samples; the outlet pipe is connected to an air pump to draw flue gas from the triangular flask into the absorption tube.

[0013] The absorption tube is a U-shaped porous glass plate absorption tube.

[0014] The number of absorption tubes is the same as the fraction of flue gas liquid samples collected, and multiple absorption tubes are connected in series with each other through rubber tubes.

[0015] The two adjacent absorption tubes are connected end to end. The air inlet of the first absorption tube is connected to the sampling port of the triangular bottle, and the air outlet of the last absorption tube is connected to the air pump.

[0016] The absorption tube contains acetone absorption liquid, and the volume of the absorption liquid is 10 ml.

[0017] The air pump has a flow rate of 0.8 L / min to 1.0 L / min.

[0018] In step 2), the three flue gas liquid samples collected by the generator and sampling device are respectively placed into volumetric flasks for processing, specifically as follows:

[0019] Pour the liquid from each absorption tube into a volumetric flask, wash the absorption tubes with a set amount of acetone, and pour the washed acetone into their respective volumetric flasks; wait for the acetone to be diluted to volume, shake well, load the sample, and mix the treated flue gas liquid sample into the same injection bottle.

[0020] The conditions used in the gas chromatography method are as follows:

[0021] The column membrane thickness is 0.25 μm, and the capillary length and inner diameter of the column are 30 m × 0.25 mm.

[0022] The initial temperature of the column oven is 140℃, and it is maintained for X min. Then, the temperature is increased to 220℃ at a rate of 20℃ / min, and maintained for Y min.

[0023] The carrier gas is helium, and the carrier gas flow rate is 1.2 ml / min;

[0024] Split injection with a split ratio of 3:1, an injection port temperature of 300℃, and an injection volume of 1μL;

[0025] The detector is a flame ionization detector with a temperature of 320℃, a hydrogen flow rate of 30 ml / min, an air flow rate of 300 ml / min, and a nitrogen tail gas with a tail gas flow rate of 30 ml / min.

[0026] Step 3) specifically includes:

[0027] a. Based on the set air pump flow rate and the set sampling time, the flue gas sampling volume is obtained as follows:

[0028] Sampling volume = air pump flow rate × sampling time

[0029] b. The mass of pyrethroids in the flue gas sample was measured using gas chromatography, i.e.:

[0030] Pyrethroid mass = Pyrethroid concentration × 10 ml / 1000

[0031] c. The total mass of pyrethroids is the sum of the masses of pyrethroids in each absorption tube;

[0032] d. The conversion rate R is obtained based on the total mass of pyrethroids and the mass of the mosquito coil, and is calculated using the following formula:

[0033] Mosquito coil mass = Total pyrethroid mass / Conversion rate × 100

[0034] e. The exposure concentration of mosquito coils is:

[0035] Exposure concentration of mosquito coil = mass of mosquito coil / sampling volume × 1000.

[0036] The present invention has the following beneficial effects and advantages:

[0037] 1. This invention first designs a method for determining the conversion rate. A certain amount of pyrethroid-based mosquito coils are burned, and all the generated smoke is collected. The pyrethroid content in the smoke is determined by gas chromatography, thereby calculating the ratio (R%) of the mass of pyrethroids in the smoke to the mass of the mosquito coils that produced the smoke, i.e., the conversion rate. This lays the foundation for determining the exposure dose of dynamic inhalation toxicity of pyrethroid-based mosquito coils.

[0038] 2. This invention designs a method for collecting, processing, and measuring pyrethroid disc mosquito smoke, which enables the smoke produced by combustion to be collected effectively, and after processing, the content can be determined by gas chromatography to obtain the exposure concentration in dynamic inhalation toxicity tests.

[0039] 3. This invention designs a dynamic toxicity inhalation test toxicity dose, i.e. exposure dose. The determination method of this invention is to measure the pyrethroid content in the smoke, divide it by the conversion rate (R%) to obtain the mass of the mosquito coil, and then calculate the exposure dose. The method is simple, practical and accurate. Attached Figure Description

[0040] Figure 1 This is a flowchart of the method of the present invention;

[0041] Figure 2 This is a schematic diagram of the generation and sampling device of the present invention;

[0042] Figure 3 This is a typical chromatogram of the standard solution of the present invention;

[0043] Figure 4 This is a specific chromatogram of flue gas liquid sample according to the present invention;

[0044] Figure 5 This is a chromatogram of the recovery rate of the flue gas liquid sample according to the present invention;

[0045] Figure 6 This is a chromatogram for the determination of the conversion rate of flue gas liquid samples according to the present invention;

[0046] Figure 7 This is a chromatogram of the exposed sample from the flue gas liquid sample inhalation test of the present invention. Detailed Implementation

[0047] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments.

[0048] like Figure 1 The diagram shown is a flowchart of the method of the present invention. The present invention discloses a method for determining the exposure concentration of pyrethroid mosquito coils in a dynamic inhalation toxicity test, comprising the following steps:

[0049] 1) After igniting a set weight of pyrethroid-based mosquito coil, collect three samples of smoke liquid using a generator and sampling device;

[0050] 2) Take three flue gas liquid samples collected by the generator and sampling device, pour the liquid from each absorption tube into a volumetric flask, wash the absorption tubes with a set amount of acetone, and pour the washed acetone into their respective volumetric flasks; wait for the acetone to be diluted to volume, shake well, load the sample, and mix the processed flue gas liquid samples into the same injection bottle, and measure the mass of pyrethroids in the sample flue gas by gas chromatography.

[0051] The conditions used in gas chromatography are as follows:

[0052] The column membrane thickness is 0.25 μm, and the capillary length and inner diameter of the column are 30 m × 0.25 mm.

[0053] The initial temperature of the column oven is 140℃, and it is maintained for X min. Then, the temperature is increased to 220℃ at a rate of 20℃ / min, and maintained for Y min.

[0054] The carrier gas is helium, and the carrier gas flow rate is 1.2 ml / min;

[0055] Split injection with a split ratio of 3:1, an injection port temperature of 300℃, and an injection volume of 1μL;

[0056] The detector is a flame ionization detector with a temperature of 320℃, a hydrogen flow rate of 30 ml / min, an air flow rate of 300 ml / min, and a nitrogen tail gas with a tail gas flow rate of 30 ml / min.

[0057] Pour the liquid from each absorption tube into a volumetric flask. Wash each absorption tube with a predetermined amount of acetone and pour the washed acetone into its respective volumetric flask. Wait for the acetone to dilute to volume, shake well, and then load the sample.

[0058] 3) Based on the mass of pyrethroids in the flue gas and the sampling volume of the generator and sampling device, the conversion rate of pyrethroid-based mosquito coils is obtained; and based on the obtained conversion rate of pyrethroid-based mosquito coils, the exposure concentration of pyrethroid-based mosquito coils is obtained.

[0059] like Figure 2 The diagram shown is a schematic of the generation and sampling device of the present invention. The generation and sampling device of the present invention includes: a triangular flask, an absorption tube and an air pump connected in sequence.

[0060] The triangular bottle is used to hold a burning pyrethroid-based mosquito coil. The side of the triangular bottle has an air inlet to supply air to support the burning of the mosquito coil. The top of the triangular bottle is sealed and has a sampling port that is connected to an absorption tube.

[0061] The inlet pipe of the absorption tube is connected to the sampling port to collect flue gas liquid samples; the outlet pipe is connected to an air pump to draw flue gas from the triangular flask into the absorption tube; the flow rate of the air pump is 0.8L / min to 1.0L / min.

[0062] The absorption tube is a U-shaped porous glass plate absorption tube; the number of absorption tubes is the same as the fraction of flue gas liquid samples collected, and multiple absorption tubes are connected in series by rubber tubes; adjacent absorption tubes are connected end to end, the air inlet of the first absorption tube is connected to the sampling port of the triangular flask, and the air outlet of the last absorption tube is connected to the air pump; the absorption tube contains acetone absorption liquid, and the volume of the absorption liquid is 10ml.

[0063] Step 3), specifically:

[0064] a. Based on the set air pump flow rate and the set sampling time, the flue gas sampling volume is obtained as follows:

[0065] Sampling volume = air pump flow rate × sampling time

[0066] b. The mass of pyrethroids in the flue gas sample was measured using gas chromatography, i.e.:

[0067] Pyrethroid mass = Pyrethroid concentration × 10 ml / 1000

[0068] c. The total mass of pyrethroids is the sum of the masses of pyrethroids in each absorption tube;

[0069] d. The conversion rate R is obtained based on the total mass of pyrethroids and the mass of the mosquito coil, and is calculated using the following formula:

[0070] Mosquito coil mass = Total pyrethroid mass / Conversion rate × 100

[0071] e. The exposure concentration of mosquito coils is:

[0072] Exposure concentration of mosquito coil = mass of mosquito coil / sampling volume × 1000.

[0073] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0074] Example 1:

[0075] Reference Figure 6 As shown, the conversion rate is determined by the ratio (R%) of the mass of pyrethroids produced in the smoke from the combustion of pyrethroid mosquito coils to the mass of the mosquito coil that produced the smoke. Among other things, such as... Figure 3 The image shows a typical chromatogram of the standard solution of this invention;

[0076] A certain amount of pyrethroid-based mosquito coils are burned, and the resulting smoke is collected. The pyrethroid content in the smoke is determined by gas chromatography, and the ratio (R%) of the mass of pyrethroids in the smoke to the mass of the mosquito coil that produced the smoke is calculated, i.e., the conversion rate. The steps for determining the conversion rate are as follows:

[0077] Step 1: Sample generation

[0078] Weigh out a certain amount of pyrethroid-based mosquito coil (approximately 1g), ignite it, and place it in an Erlenmeyer flask. The flask has an air inlet at the bottom to provide air for combustion. The top of the flask is sealed and has a sampling port. The sampling port is connected to three absorption tubes (three in series), and the other end of each tube is connected to a sampler. Start the sampler and collect the generated smoke into the absorption tubes. After no more smoke is produced, continue collecting for 10 minutes. Collect three samples using the same method.

[0079] The method for collecting flue gas samples is as follows:

[0080] Sample collection absorption tube: U-shaped porous glass plate absorption tube, three stages in series.

[0081] Sample collection and absorption solution: acetone;

[0082] Absorption liquid volume: 10 ml in each absorption tube;

[0083] Air pump flow rate: 0.8 L / min;

[0084] Step 2: Sample processing and determination

[0085] Pour the liquid from the three-stage absorption tubes into separate 10ml volumetric flasks. Wash each absorption tube with an appropriate amount of acetone, and pour the washings into the respective volumetric flasks. Make up to volume with acetone and mix well. Transfer 200μl each of the first, second, and third-stage solutions to the same injection vial, mix well, and then load for analysis. The gas chromatographic conditions for sample analysis are as follows:

[0086] Chromatographic column: DB-1, 0.25 μm, 30 m × 0.25 mm; Column oven temperature: initial 140 °C, hold for 2 min, then ramp up to 220 °C at a rate of 20 °C / min, hold for 8 min. Carrier gas: helium, carrier gas flow rate 1.2 ml / min. Split injection, split ratio 3:1, injector temperature 300 °C, injection volume 1 μl. Detector: FID, detector temperature 320 °C, hydrogen flow rate 30 ml / min, air flow rate 300 ml / min, make-up gas: nitrogen, make-up gas flow rate 30 ml / min.

[0087] Step 3: Conversion Rate Calculation

[0088] The mass of pyrethroid precursor in flue gas (mg) = concentration of absorbent (mg / L) × volume of absorbent (ml) / 1000

[0089] Mosquito coil mass (mg) = Mosquito coil mass before burning (mg) - Mosquito coil mass remaining after burning (mg)

[0090] Conversion rate (R%) = (Mass of original pyrethroid in flue gas (mg) / Mass of mosquito coil (mg)) × 100

[0091] The conversion rate determination was performed in triplicate. The initial weights of the mosquito coils before combustion were 0.937 g, 0.945 g, and 0.913 g, respectively. After complete combustion, the weight of the mosquito coils after combustion was 0 g, and the final weights were 0.937 g, 0.945 g, and 0.913 g, respectively. The concentrations of the absorbent solution were 4.372 mg / L, 5.095 mg / L, and 5.417 mg / L, respectively. The volume of the absorbent solution was 30 ml for all measurements. The initial mass of pyrethroids in the flue gas was 0.13115 mg, 0.15284 mg, and 0.16251 mg, respectively. The conversion rates were 0.014%, 0.016%, and 0.018%, respectively, with an average of 0.016% and a relative standard deviation of 11.9%.

[0092] Example 2:

[0093] like Figure 4 The image shows a specific chromatogram of flue gas liquid samples according to the present invention, and the specificity determination method of the present invention is shown.

[0094] In this embodiment, an appropriate amount of acetone was placed in a vial as a blank control sample for analysis. The gas chromatographic conditions for sample analysis are as follows:

[0095] Chromatographic column: DB-1, 0.25 μm, 30 m × 0.25 mm; Column oven temperature: initial 140 °C, hold for 2 min, then ramp up to 220 °C at a rate of 20 °C / min, hold for 8 min. Carrier gas: helium, carrier gas flow rate 1.2 ml / min. Split injection, split ratio 3:1, injector temperature 300 °C, injection volume 1 μl. Detector: FID, detector temperature 320 °C, hydrogen flow rate 30 ml / min, air flow rate 300 ml / min, make-up gas: nitrogen, make-up gas flow rate 30 ml / min.

[0096] Results: The blank sample was not detected at the retention time of the test sample.

[0097] Example 3:

[0098] Reference Figure 5As shown, the accuracy and precision of the method were determined by using an absorbent solution with a concentration of 5.095 mg / L as the matrix solution, adding a certain amount of a standard solution of known concentration (5.0 mg / L), and then determining the accuracy and precision of the recovery rate. The determination steps are as follows:

[0099] Take 200 μl each of the matrix solution and the additive standard solution into a vial, mix well, and then load for analysis. Prepare five parallel samples. The gas chromatographic conditions for sample analysis are as follows:

[0100] Chromatographic column: DB-1, 0.25 μm, 30 m × 0.25 mm; Column oven temperature: initial 140 °C, hold for 2 min, then ramp up to 220 °C at a rate of 20 °C / min, hold for 8 min. Carrier gas: helium, carrier gas flow rate 1.2 ml / min. Split injection, split ratio 3:1, injector temperature 300 °C, injection volume 1 μl. Detector: FID, detector temperature 320 °C, hydrogen flow rate 30 ml / min, air flow rate 300 ml / min, make-up gas: nitrogen, make-up gas flow rate 30 ml / min.

[0101] The standard curve has a quantitative range of 0.500 mg / L to 20.00 mg / L. The accuracy of regression calculations at each concentration point is between 92.5% and 107.7%, and the correlation coefficient (R) is greater than 0.999.

[0102] The accuracies for the five recovery rate samples were 98.8%, 108.1%, 106.1%, 101.4%, and 96.9%, respectively, with an average accuracy of 102.3% and a relative standard deviation of 4.6%.

[0103] Example 4:

[0104] Reference Figure 7 As shown, the exposure dose determination in the dynamic inhalation toxicity test of pyrethroid disc mosquito coils;

[0105] A mosquito coil was lit and placed in an exposure tower. The smoke was collected, and the pyrethroid content in the smoke was determined by gas chromatography. The mass of the mosquito coil was then calculated, and the exposure dose of the mosquito coil in the inhalation test was determined. The steps for determining the exposure dose are as follows:

[0106] Step 1: Sample Generation and Collection

[0107] Take an appropriate amount of mosquito coil, light it, and place it in the exposure tank (exposed tower). Adjust the parameters of the exposure tank. After the sample in the exposure tank stabilizes, take three absorption tubes containing absorption liquid and connect them in series with rubber tubing. Connect one end of the absorption tube to the sampling port of the exposure tank, and the other end to the air pump. Start the air pump, which will draw the flue gas from the exposure tank into the absorption tubes.

[0108] The method for collecting flue gas samples is as follows:

[0109] Sample collection absorption tube: U-shaped porous glass plate absorption tube, three stages in series.

[0110] Sample collection and absorption solution: acetone;

[0111] Absorption liquid volume: 10 ml in each absorption tube;

[0112] Air pump flow rate: 1L / min;

[0113] Data collection time: 15 minutes.

[0114] Step 2: Sample processing and determination

[0115] Pour the liquid from each absorption tube into a 10 ml volumetric flask. Wash each absorption tube with an appropriate amount of acetone, and pour the washing solution into the respective volumetric flask. Make up to volume with acetone and mix well. Mix equal volumes of the first and second stage solutions (500 μl each), mix well, and load the solution to determine the concentration of pyrethroids in the diluted solution. For the third stage solution, directly load the solution to determine the concentration of pyrethroids in the solution. The gas chromatographic conditions for sample determination are as follows:

[0116] Chromatographic column: DB-1, 0.25 μm, 30 m × 0.25 mm; Column oven temperature: initial 140 °C, hold for 2 min, then ramp up to 220 °C at a rate of 20 °C / min, hold for 8 min. Carrier gas: helium, carrier gas flow rate 1.2 ml / min. Split injection, split ratio 3:1, injector temperature 300 °C, injection volume 1 μl. Detector: FID, detector temperature 320 °C, hydrogen flow rate 30 ml / min, air flow rate 300 ml / min, make-up gas: nitrogen, make-up gas flow rate 30 ml / min.

[0117] Step 3: Calculation of Exposure Dose

[0118] a. Sampling volume (L) = Air pump flow rate (L / min) × Sampling time (min)

[0119] b. Mass of pyrethroids in the sample (mg) = Pyrethroid concentration (mg / L) × Absorption liquid volume (ml) / 1000

[0120] c. Mass of mosquito coil (mg) = Total mass of pyrethroids in the sample (mg) / Conversion rate (R) × 100

[0121] d. Exposure concentration of mosquito coil (mg / m3) = Mass of mosquito coil (mg) / Sampling volume (L) × 1000

[0122] During the formal inhalation exposure, two concentration measurements were performed. For both measurements, the sampling pump flow rate was 1 L / min, the sampling time was 15 min, and the sampling volume was 15 L. No sample peaks were detected in the third-stage sampling tube for either concentration measurement. The pyrethroid concentrations in the samples measured were 2.194 mg / L and 2.350 mg / L, respectively, with an absorption liquid volume of 20 ml for both measurements. The pyrethroid mass in the samples measured were 0.044 mg and 0.047 mg, respectively. These are equivalent to 275.0 mg and 293.8 mg of mosquito coil, respectively. The corresponding exposure concentrations in mosquito coils were 18333 mg / m³ and 19587 mg / m³, respectively.

[0123] In summary, this invention uses gas chromatography to determine the pyrethroid content in the smoke produced after burning a certain amount of mosquito coil, and calculates the mass ratio (R%) of pyrethroids in the smoke to the mosquito coil, i.e., the conversion rate. Then, by measuring the pyrethroid content in the smoke after burning a mosquito coil in a poison canister, and then calculating the mass of the mosquito coil using the conversion rate, the exposure dose for inhalation toxicity testing can be calculated, laying the foundation for determining the dynamic inhalation toxicity exposure dose of pyrethroid-based mosquito coils.

[0124] This invention enables the flue gas produced by combustion to be collected effectively, and the content can be determined by gas chromatography after treatment.

[0125] The foregoing display and description illustrate the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for determining the exposure concentration of pyrethroid-based disc mosquito coils in a dynamic inhalation toxicity test, characterized in that, Includes the following steps: 1) After burning a set weight of pyrethroid-based mosquito coil, collect three samples of smoke liquid using a sampling device; The generating and sampling device includes: a triangular flask, an absorption tube, and an air pump connected in sequence; The triangular bottle is used to hold burning pyrethroid-based mosquito coils. The triangular bottle has an air inlet on its side to supply air to support the burning of the mosquito coil; the top of the triangular bottle is sealed and has a sampling port, which is connected to the absorption tube. The inlet pipe of the absorption tube is connected to the sampling port to collect flue gas liquid samples; the outlet pipe is connected to an air pump to draw flue gas from the triangular flask into the absorption tube. The number of absorption tubes is the same as the fraction of flue gas liquid samples collected, and multiple absorption tubes are connected in series with each other through rubber tubes. The two adjacent absorption tubes are connected end to end, with the air inlet tube of the first absorption tube connected to the sampling port of the triangular bottle, and the air outlet tube of the last absorption tube connected to the air pump. 2) The three flue gas liquid samples collected by the generator and sampling device were placed into volumetric flasks for processing. The processed flue gas liquid samples were then mixed in the same injection bottle. After being mixed evenly, the mass of pyrethroids in the sample flue gas was measured by gas chromatography. In step 2), the three flue gas liquid samples collected by the generator and sampling device are respectively placed into volumetric flasks for processing, specifically as follows: Pour the liquid from each absorption tube into a volumetric flask, wash the absorption tubes with a set amount of acetone, and pour the washed acetone into their respective volumetric flasks; wait for the acetone to be diluted to volume, shake well, load the sample, and mix the treated flue gas liquid samples in the same injection bottle. 3) Based on the mass of pyrethroids in the flue gas and the sampling volume of the generator and sampling device, the conversion rate of pyrethroid-based mosquito coils is obtained; and based on the obtained conversion rate of pyrethroid-based mosquito coils, the exposure concentration of pyrethroid-based mosquito coils is obtained. Step 3) specifically refers to: a. Based on the set air pump flow rate and the set sampling time, the flue gas sampling volume is obtained as: Sampling volume = Air pump flow rate × Sampling time b. The mass of pyrethroids in the sample flue gas was measured by gas chromatography, i.e.: Pyrethroid mass = Pyrethroid concentration × 10 ml / 1000 c. The total mass of pyrethroids is the sum of the masses of pyrethroids in each absorption tube; d. The conversion rate R is obtained from the total mass of pyrethroids and the mass of the mosquito coil using the following formula: Mass of mosquito coil = Total mass of pyrethroids / Conversion rate × 100 e. The exposure concentration of mosquito coils is: Exposure concentration of mosquito coil = mass of mosquito coil / sampling volume × 1000.

2. The method for determining the exposure concentration of pyrethroid mosquito coils in dynamic inhalation toxicity testing according to claim 1, characterized in that, The absorption tube is a U-shaped porous glass plate absorption tube.

3. The method for determining the exposure concentration of pyrethroid mosquito coils in dynamic inhalation toxicity testing according to claim 1, characterized in that, The absorption tube contains acetone absorption liquid, and the volume of the absorption liquid is 10 ml.

4. The method for determining the exposure concentration of pyrethroid mosquito coils in dynamic inhalation toxicity testing according to claim 1, characterized in that, The air pump has a flow rate of 0.8 L / min to 1.0 L / min.

5. The method for determining the exposure concentration of pyrethroid mosquito coils in dynamic inhalation toxicity testing according to claim 1, characterized in that, The conditions used in the gas chromatography method are as follows: The column membrane thickness is 0.25 μm, and the capillary length and inner diameter of the column are 30 m × 0.25 mm. The initial temperature of the column oven is 140℃, and it is maintained for X min. Then, the temperature is increased to 220℃ at a rate of 20℃ / min, and maintained for Y min. The carrier gas is helium, and the carrier gas flow rate is 1.2 ml / min; Split injection with a split ratio of 3:1, an injection port temperature of 300℃, and an injection volume of 1μL; The detector is a flame ionization detector with a temperature of 320℃, a hydrogen flow rate of 30 ml / min, an air flow rate of 300 ml / min, and a nitrogen tail gas with a tail gas flow rate of 30 ml / min.

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