Device for exposing biological organisms to the waters of an aquatic system

Abstract

Device for exposing biological organisms to the waters of an aquatic system Device (1) for exposing biological organisms to the waters of an aquatic system, comprising: - at least one thermoregulation tank (14, 15) for the waters taken from the aquatic system, - one or more exposure tanks (20) for the biological organisms, - at least one measuring tank (21) with one or more physicochemical probes, the waters taken making a circuit in the device (1) without a return loop. Figure for the abstract: Fig. 1

Description

Title of the invention: Device for exposing biological organisms to the waters of an aquatic system Technical field

[0001] The present invention relates to ex-situ biomonitoring of the water quality of an aquatic system.

[0002] This involves determining the toxicity of the waters of an aquatic system, in particular with respect to biological organisms such as plants or animals, fish among others, in particular on the embryonic or larval stages of these biological organisms, during which sensitivity to toxic agents is particularly high. Thus, during these stages, the effects of toxic agents can be detected more easily and quickly. Prior art

[0003] There are in-situ water monitoring devices, as for example described in application FR 1 852 818, the method of which is based on the caging of organisms directly in the environments and their use for measuring markers, in particular on reprotoxicity. However, this method is not transposable to many aquatic organisms, plants and animals, in particular such as fish embryos.

[0004] We also know the article Luckenbach et al 2001 Chemosphere "Toxicity of waters from 2 streams to early life stages of brown trout Salmo trutta fario, tested under semi-field conditions". In this article, a diversion system is proposed but it is composed of a single tank which receives the embryos, with a capacity of 200 liters. This tank is fed from another tank which is also 200 liters, which makes it a system which is not very mobile and therefore not very generalizable.

[0005] A water tank for monitoring fish is known from utility model JP 3095182 U, in which part of the water leaving the exposure tank is recycled for reuse in the device, which may affect the reliability of the study.

[0006] There is a need to improve and facilitate ex-situ biomonitoring, in particular by continuous diversion and withdrawal of water, the quality of the waters of an aquatic system, and to increase its reliability. Summary of the invention

[0007] The invention aims to meet this need and thus has as its subject a device for exposing biological organisms to the waters of an aquatic system, in particular taken continuously, in particular intended to carry out biomonitoring of the quality waters of the aquatic system, including: - at least one thermoregulation tank for water taken, in particular continuously, from the aquatic system, in particular by pumping, - one or more tanks for displaying biological organisms, - at least one measuring tank with one or more physicochemical probes, the water taken making a circuit in the device without a return loop.

[0008] The invention makes it possible to carry out automated ex-situ biomonitoring of aquatic systems, by exposing biological organisms to the waters of these systems, continuously, under controlled and optimal conditions for their development and thus assessing their toxicity. The invention thus makes it possible to overcome the difficulty of exposing certain aquatic organisms directly in the aquatic system to be studied.

[0009] By 'aquatic system' is meant a natural or non-natural environment, preferably natural, comprising one or more animal and / or plant species, whether living or not. It may be a system with fresh water or marine water or transitional water. It may be lotic, lentic or reservoir systems, or a discharge such as effluent from treatment plants. It may be natural or artificial systems, such as for example sea, ocean, coastal zone, river, stream, torrent, lake, swamp, marsh, peat bog, reservoir, estuary, lagoon, lagoon, mangrove, among others. It may be aqueous discharges before their discharge into a natural or artificial environment, such as discharges from treatment plants, drinking water treatment plants or industrial water treatment plants.

[0010] Thus, it is possible to capture the waters of an aquatic system, oxygenate them if necessary, regulate their temperature, supply the exposure tanks, then return the studied waters to the aquatic system.

[0011] The water sampled can be sampled continuously, for example up to 60 L / h, from the aquatic system.

[0012] The plurality of exposure tanks can make it possible to carry out exposure replications using biological organisms of the same species, and / or to expose biological organisms from different species to the water. The use of several exposure tanks can allow the simultaneous exposure of biological organisms which may be predators of each other and therefore must not be mixed. Alternatively, biological organisms of several species can be placed in the same exposure tank to study their interactions. Thus, the device according to the invention makes it possible to expose different species, including for example predatory species, in isolation, and it advantageously makes it possible to make replicas.

[0013] The biological organism(s) exposed to the water may be chosen from the following list, which is not exhaustive: plants, plants, such as for example Myriophyllum aquaticum, Ceramium tenuicorne, vertebrates in the egg stages, embryos, or adults, such as fish or amphibians, invertebrates in the egg, embryo, larval or adult stages such as arthropods, echinoderms, molluscs, annelids, nematodes, platyhelminthes, cnidarians or sponges. The biological organism(s) may be introduced into the device at the embryonic stage. The invention makes it possible, for example, to monitor the development of eggs of aquatic organisms.

[0014] The biological organism(s) may include one or more species that are difficult to expose in the natural environment, whose response when exposed in the aquatic system may be desired to be studied. The device may also include species that can be caged in the environments but for one period of the year only. With temperature regulation, it becomes possible to expose aquatic organisms all year round, such as bivalve larvae, echinoderm larvae, insect larvae, but also all species during periods outside thermal tolerance such as gammarids and gastropods in particular.

[0015] The device according to the invention makes it possible, using cameras in particular, to monitor the development and growth of biological organisms exposed to the waters of an aquatic system. For example, their growth can be observed until they hatch, or even a few days after hatching, for example 2 to 3 days after hatching. The device may, for example, include one or more cameras making it possible to take photos at regular intervals and store them on an on-board computer.

[0016] When the observation is finished, in particular when the development time is reached, the water from the aquatic system can be automatically stopped from circulating in the device and a euthanizing product can be poured into the measuring tank(s), which makes it possible to stop growth. The evolution of development and survival can be analyzed a posteriori using the photos taken and recorded. The ability to euthanize exposed living organisms, without risk of contaminating the water of the aquatic system studied, is an essential point for the use of organisms, such as fish embryos and larvae which are subject to ethical regulations. Finally, the possibility of analyzing a posteriori the effects on growth, hatching or any other response of the exposed organisms from the photos taken by the camera is also an essential point in monitoring.The termination of the study by euthanasia and the deferred analysis of the results means that there is no constraint on dates for visiting the site, nor any constraint for recovering the organisms, which is a key point in biomonitoring.

[0017] The invention makes it possible to ensure optimal and controlled temperature, oxygenation and light conditions, which vary according to the species of biological organisms used, in order to qualify and evaluate the chemical toxicity of the aquatic system studied.

[0018] The device may in particular comprise a single exposure tank or several, for example between 2 and 20, or even between 3 and 15, better still between 4 and 10, in particular between 5 and 8.

[0019] The volume of an exhibition tank can for example be between 0.1 and 10 L, better between 0.2 and 5 L, or even between 0.3 and 2 L, being for example 0.5 L.

[0020] The device may in particular comprise a measuring tank which may be similar to an exposure tank, in particular in its shape and dimensions.

[0021] The measuring tank(s) can be used to monitor one or more physicochemical parameters of the sampled water. Indeed, biological organisms may not tolerate any physicochemical conditions. These parameters are therefore monitored in order to protect the biological organisms, not to affect their development, and not to distort the exposure observations.

[0022] Thanks to the invention, the quality of the water in the exposure and measurement tanks can be monitored in real time.

[0023] The physicochemical parameters can be chosen from the following list, which is not limiting: temperature, pH and conductivity of the water.

[0024] Each exposure tank may comprise a filtration unit, in particular placed at the outlet of the corresponding exposure tank, in order to prevent the escape of biological organisms contained in said exposure tank, and their release into the aquatic system.

[0025] The water collected in the device according to the invention forms a circuit without a return loop, that is to say without a water recycling loop, while allowing them to be maintained at the set temperature regardless of the flow rate. The device according to the invention is without a recycling loop system, in particular for recycling or reusing the water leaving the device. The absence of a recycling loop, despite the high flow rate, makes it possible not to dilute in an artifactual manner the water pumped from the aquatic system studied and consequently to ensure that the water exposing the organisms best represents the water of the aquatic system, with the variations in its quality over time integrating point pollution, by peaks.The presence of a recycling loop can, on the contrary, lead to an increase in the residence time of the water in the device and therefore to a dilution of the level of contaminants brought by peak into the aquatic system and consequently to a minimization of the exposure of organisms and the toxic effects and thus bias the evaluation of the toxicity of the aquatic systems studied. The water leaving the device can be discharged into the aquatic system from which the water was taken. Statement of the invention

[0026] Thermoregulation of the water sampled makes it possible to adapt the temperature of the water in the device to the biological organisms exposed to it. Some need a warmer environment, others a colder environment. It makes it possible to expose biological organisms, in particular fish embryos, to any river water and in any season. In a natural environment, the temperature of the River water varies greatly depending on the geographical location of the study, the time of day and the season. Biological organisms have very different thermal tolerance ranges from one another; there are so-called cold species and others so-called hot species. In addition, temperature is a parameter that plays a major role in biology because it controls many physiological responses such as feeding, growth, duration of embryonic development, etc., commonly used in ecotoxicology as markers to assess the presence and impact of contaminants present in the environment. It is difficult to envisage describing the effect of this parameter on all the physiological responses measured in sentinel species in ecotoxicology. In addition, some organisms and species cannot be directly exposed in the environment, particularly using cages.Therefore, and in order to be able to compare the measured responses between several sites and use the organisms whatever the time of year, the regulation and control of the exposure temperature is an essential and crucial point for proposing this device for monitoring, on a large scale and for numerous species.

[0027] The exposure tank(s) may be placed at the same study temperature. For cold water species, the study temperature may, for example, be between 8 and 16°C, or even between 10 and 14°C, being, for example, of the order of 11°C. For warm water species, the study temperature may, for example, be between 16 and 28°C, or even between 20 and 24°C, being, for example, of the order of 22°C.

[0028] Said at least one thermoregulation tank may comprise a system for circulating the collected water, which is in thermal contact with a thermoregulation liquid.

[0029] The thermoregulation liquid can receive the evacuation water from the exposure tank(s). Thus, the water taken, in particular to be heated or cooled, is brought into thermal contact with the exposure water which has been thermally regulated, in particular hotter or colder, for example the outlet water from the exposure device.

[0030] Such a configuration allows energy savings. The outlet waters allow the sampled waters to be heated or cooled, in order to bring them to the desired study temperature for exposure to biological organisms.

[0031] The device may comprise one or more aquarium resistors, for example with a power of 1000 W, in order to heat the thermoregulation liquid.

[0032] Alternatively or additionally, the device may include a cooling unit for cooling the sampled water, depending on the desired study temperature. The cooling unit may, for example, have a power of 370 W.

[0033] It is thus possible to obtain fine regulation of the temperature of the water in the device. The thermoregulation of the device according to the invention can be particu- highly efficient and economical.

[0034] The circulation system may comprise a pipe in which the collected water circulates, for example made of flexible plastic. It may be wound into a serpentine.

[0035] The pipe may have a length of between 50 and 200 m, better between 75 and 150 m, or even between 85 and 120 m, being for example 100 m long.

[0036] The flow speed in the pipe can be between 0.8 and 3.3 m / s, better between 1 and 2.8 m / s, or even between 1.5 and 2.4 m / s, being for example 2.1 m / s.

[0037] An exchange time between the water taken and the thermoregulation liquid can be between 4 and 260 seconds, better between 7 and 100 s, or even between 24 and 57 s, being for example 48 s.

[0038] The pipe can be made from a material chosen from the following list, which is not limiting: Silicone, Polyethylene, crystal PVC.

[0039] The section of the wall of the pipe can be between 5 and 22 mm, better between 6 and 17 mm, or even between 7 and 11 mm, being for example of the order of 8 mm.

[0040] The device may comprise a single thermoregulation tank, or several.

[0041] In one embodiment, the device comprises two thermoregulation tanks. It can thus comprise a first thermoregulation tank and a second thermoregulation tank placed in series. The use of several thermoregulation tanks can make it easier to choose and adapt the study temperature, while allowing energy savings.

[0042] The device thus makes it possible to maintain the water temperature constant in the exhibition tanks where the biological organisms are exposed and is sized to receive so-called cold and hot species regardless of the temperature of the water taken.

[0043] The water collected passes successively through the first thermoregulation tank and then through the second thermoregulation tank. The temperature of the water collected can thus be regulated successively at two successive temperatures, before entering the exposure tank(s).

[0044] One of the first or second thermoregulation tanks may be arranged below the exposure tank(s), as will be explained later, in particular the first thermoregulation tank. In one embodiment, the first thermoregulation tank receives the drain water from the exposure tanks, then the second thermoregulation tank comprises the regulation equipment, resistors and refrigeration units.

[0045] The device may comprise a storage tank for water taken from the aquatic system, arranged upstream of the thermoregulation tank(s).

[0046] A pump may be used to allow water to be drawn from the aquatic system and brought up into the storage tank. The pump may be submerged in the aquatic system. For example, it may be a pump capable of pumping continuously with a high flow rate, for example around 60 L / h to 100 L / h, in order to ensure good renewal of the water taken and reflect the variability of the water quality of the aquatic system.

[0047] The storage tank may be equipped with a filtration system, in order to filter the water taken from the aquatic system before it enters the device. This makes it possible to limit the intake of larger particles into the device and in particular into the display tanks. The filtration system may be placed in the center of the storage tank and comprise three layers of mesh with increasingly smaller openings, from the outside to the inside of the filtration system. The filtered water, present in the center of the filtration system and continually renewed, is then used to supply the device.

[0048] The device may include a water oxygenation system. Oxygenation of the water can be achieved by bubbling the water present in a storage tank. Oxygenation is preferably carried out upstream of a pump of the device, because after pumping, the water is in the thermoregulation and distribution system and therefore not accessible before being discharged into the exposure tank with the organisms.

[0049] Oxygenation is advantageously carried out in a tank through which all the water taken passes, so that oxygenation is carried out in a single tank, with a single oxygenation system, which is more economical.

[0050] Alternatively, the oxygenation may be carried out in one or more of the exposure tanks. In this case, the device comprises several oxygenation systems. Advantageously, the oxygenation may thus be adapted according to the biological organism(s) present.

[0051] The display tank(s) may each contain at least one cage in which the biological organisms are kept.

[0052] Thus, these can be easily moved or removed from the display tank, while being immersed in the sampled water and exposed to its circulation.

[0053] The device may include a water pump, arranged upstream of the thermoregulation tank(s). The use of a pump makes it possible to ensure a certain flow rate in the device, which may be quite high. The flow rate may be between 2 and 200 L / h, better between 10 and 150 L / h, or even between 40 and 100 L / h, for example being of the order of 60 L / h. It may be a membrane pump.

[0054] This results in a circulation of the water taken from the device, and a renewal of this water in each tank crossed. The renewal rate can for example be 12 per day, in particular by overflow then return to the aquatic system.

[0055] The display tray(s) can thus be supplied continuously.

[0056] The exhibition tank(s) may be overflowing, being provided in particular with an outlet arranged in a wall of the exhibition tank. The overflow of the collected water allows circulation in the exhibition tanks. There is no automatic level control. There may be manual level control. The overflow may be made into a tank placed below the exhibition tank(s). The overflow from the exhibition tank(s) may be discharged into a temperature control tank, in particular into the first temperature control tank.

[0057] The exposure tank(s) may be supplied from the bottom, in particular below the level of liquid they contain. A supply from the bottom makes it possible to avoid eddies in the corresponding tank, and thus to avoid having ripples on the surface of the water in the tank in question and to optimize the renewal of the exposure tank. The supply may be carried out by a supply pipe dipping into the tank, in particular vertically, an outlet orifice of which is placed in the bottom of the tank.

[0058] The device may comprise a lighting system configured to allow the brightness in the display tanks to be modulated. The lighting system may allow the lighting of the different display tanks to be standardized. In addition, it may allow an alternation of day / night cycles to be reproduced artificially.

[0059] The display tray(s) may include a closing cover, in order to facilitate lighting control and not depend on natural lighting.

[0060] The lighting system may comprise one or more light sources, in particular LEDs (light-emitting diodes) and one or more screens in front of the light source(s). The screen(s) are configured to prevent direct illumination of the organisms by the light sources and to avoid reflections in the water.

[0061] The device may also include one or more cameras for monitoring the development of biological organisms, in particular embryos.

[0062] The physicochemical probe(s) may comprise at least one of: autonomous temperature probe, pH probe, conductivity / salinity probe, this list not being limiting.

[0063] The device may comprise a central unit for controlling and recording the collected data, for storing the measured physicochemical data and the photos taken. This makes it possible to manage in real time the regulation of the temperature to the requested setpoint, to control the lighting cycles and to record the measured physicochemical parameters and the photos. The images from the camera(s) also make it possible to observe the biological organisms.

[0064] A largest dimension of the device may be less than 2 m, better still less than 1.8 m, or even less than 1.6 m, even better still less than 1.4 m or 1.2 m, being for example of the order of 1 m. Advantageously, the dimensions of the device are rela- tively small, which makes it easy to transport and deploy.

[0065] The total volume of the device, which corresponds to a total capacity thereof, can be between 1 and 2 m3, better between 1 and 1.8 m3, or even between 1 and 1.5 m3, being for example of the order of 1.25 m3.

[0066] A capacity of an exhibition tank can be between 0.1 and 10 L, better between 0.2 and 5 L, or even between 0.3 and 2 L, being for example 0.5 L.

[0067] A total capacity of the display tanks, by adding a capacity of all the display tanks, can be between 1 and 20 L, better between 2 and 10 L, or even between 3 and 8 L, being for example 5 L.

[0068] A capacity of the storage tank can be between 10 and 60 L, better between 15 and 50 L, or even between 20 and 40 L, being for example 30 L.

[0069] The device may be configured to be movable from one location to another near an aquatic system. Advantageously, the device according to the invention is mobile.

[0070] A mass of the device may be less than 75 kg, better still less than 50 kg, or even less than 40 kg, even better still less than 30 kg, being for example of the order of 25 kg-

[0071] The device may have an electrical power cable, allowing it to be powered from a current source.

[0072] Alternatively, the device may comprise an electrical power source, for example one or more batteries, which can advantageously be used without connection to an external source. The device may be energy autonomous.

[0073] The device according to the invention advantageously has good ergonomics, and it can be handled and moved easily, it can be deployed on a large number of study sites.

[0074] The invention also relates to a use of the exposure device as defined above for biomonitoring the quality of the waters of an aquatic system. Brief description of the drawings

[0075] The invention may be better understood by reading the description which follows, non-limiting examples of its implementation, and by examining the attached drawing, in which:

[0076] [Fig.l] [Fig.l] is a schematic and partial perspective view of an exposure device produced in accordance with the invention.

[0077] [Fig.2] [Fig.2] is another schematic and partial perspective view of the device of [Fig.l].

[0078] [Fig.3] [Fig.3] is a schematic and partial top view of the device of the [Fig.l].

[0079] [Fig.4] [Fig.4] is a schematic and partial front view of the device of the [Fig.l].

[0080] [Fig.5] [Fig.5] is a schematic and partial side view of the device of [Fig.l].

[0081] [Fig.6] [Fig.6] is a schematic and partial rear view of the device of [Fig.l]. Detailed description

[0082] Figures 1 to 6 illustrate a device 1 for exposing biological organisms to the waters of an aquatic system. The invention makes it possible to carry out automated, continuous biomonitoring, under natural and controlled conditions, ex-situ, of the development of biological organisms, in particular aquatic organisms, exposed to the waters of an aquatic system. With the device according to the invention, it is possible to capture the waters of an aquatic system, oxygenate them, regulate their temperature, supply the exposure tanks, and then return the waters studied to the aquatic system.

[0083] The exhibition device 1 comprises for this purpose a frame 2 made of aluminum profiles, as well as a floor 3, to contain different containers.

[0084] The exhibition device 1 firstly comprises a storage tank 11 for the water taken from the aquatic system. A pump, not shown, is used to allow the water to be taken from the aquatic system and brought up into the storage tank 11. The pump is immersed in the aquatic system. The storage tank 11 may also be equipped with a filtration system in its centre, in order to filter the water taken from the aquatic system before it enters the device.

[0085] The device also comprises a water oxygenation system, for example in the storage tank 11.

[0086] Furthermore, the device comprises two thermoregulation tanks 14 and 15 for the water taken from the aquatic system, which are placed in series.

[0087] Each thermoregulation tank 14 and 15 comprises a system for circulating the collected water, which is in thermal contact with a thermoregulation liquid.

[0088] More precisely, the first thermoregulation tank 15 comprises a serpentine circulation system 17, with a pipe in which the collected water circulates, for example made of flexible plastic. The pipe may have a length of, for example, 100 m.

[0089] The second thermoregulation tank 1 comprises a serpentine circulation system 16, with a pipe in which the collected water circulates, for example made of flexible plastic. The pipe may have a length of, for example, 100 m.

[0090] In the first thermoregulation tank 15, the thermoregulation liquid comprises water drained from the device. Thus, the water taken to be heated or cooled are brought into thermal contact with warmer or colder waters which are the outlet waters of the exposure device.

[0091] A flow meter 13 allows a reading of the water flow rate between the two serpentine circulation systems 16 and 17.

[0092] In addition, the device may include one or more aquarium resistors, for example 1000 W, in order to heat the thermoregulation liquid, as well as a cold group 18 for cooling the water taken, depending on the desired study temperature. The cold group 18 may for example be 370 W. The water is conducted into the cold group by a circulation 18a. It is thus possible to obtain fine thermal regulation of the temperature of the water in the device.

[0093] The device comprises a membrane pump 19 for the water taken, arranged upstream of the thermoregulation tanks 14 and 15, with withdrawal from the storage tank 11 by a supply intake pipe 12, in order to ensure a certain flow rate in the device, which can be quite high. The flow rate can be for example of the order of 60 L / h.

[0094] This results in circulation of the water taken from the device, and renewal of the water in each tank crossed.

[0095] The device further comprises, supplied from the second thermoregulation tank 14, a plurality of exposure tanks 20 for the biological organisms in the water sampled, as well as a measuring tank 21, with one or more physicochemical probes, which is similar to an exposure tank, in particular by its shape and dimensions. The exposure tanks 20 each contain a cage (not shown) in which the biological organisms are kept. The volume of an exposure tank is for example approximately 0.5 L.

[0096] Each exposure tank 20 may comprise a filtration unit, placed at the outlet of the corresponding exposure tank, in order to prevent the escape of biological organisms contained in said exposure tank, and their release into the aquatic system.

[0097] The exposure tanks 20 are continuously supplied. They are overflow tanks, being provided with an outlet arranged in a wall of the exposure tank. The overflow of water collected is discharged into the first thermoregulation tank 15 placed below the exposure tanks 20.

[0098] Furthermore, the exposure tanks 20 are supplied from the bottom, below the level of liquid they contain. The supply is carried out by a supply pipe 23 plunging vertically into the tank 20, an outlet orifice of which is placed in the bottom of the tank 20.

[0099] The water collected forms a circuit in the device according to the invention without a return loop, i.e. without recycling. The water leaving the device is discharged into the aquatic system from which the water was taken, via a discharge pipe 35.

[0100] The measuring tank 21 makes it possible to monitor physicochemical parameters of the water sampled, for example temperature, pH, conductivity of the water.

[0101] Furthermore, the device comprises a lighting system configured to allow the brightness in the display tanks to be modulated. The display tanks may comprise a closing cover, in order to facilitate control of the lighting and not depend on natural lighting.

[0102] The device may also include one or more cameras for monitoring the development of biological organisms, in particular embryos.

[0103] The device may also include a system for euthanizing exposed biological organisms. This system makes it possible to stop the renewal of the exposure tanks and to inject a desired volume of euthanasia agent into each of them or into some of them.

[0104] Finally, the device comprises an electrical box 32 for powering the device, and a central unit 30 for controlling and recording the collected data, for storing the measured data and photos taken. This makes it possible to manage in real time the regulation of the temperature to the requested setpoint, to control the lighting cycles and to record the measured physicochemical parameters. The images from the camera(s) also make it possible to observe the biological organisms and to access a posteriori information on survival, growth, hatching, for example.

[0105] A larger dimension of the device is for example of the order of 1 m, which makes it easier to transport and move. The total volume of the device can be of the order of 1 m3.

Claims

Claims

1. Device (1) for exposing biological organisms to water from an aquatic system taken continuously, intended to carry out biomonitoring of the quality of the water from the aquatic system, comprising: - at least one thermoregulation tank (14, 15) for the water taken continuously from the aquatic system, - one or more exposure tanks (20) for the biological organisms, - at least one measuring tank (21) with one or more physicochemical probes, the water taken making a circuit in the device (1) without a return loop.

2. Exposure device according to the preceding claim, said at least one thermoregulation tank (14, 15) comprising a circulation system (16, 17) for the water collected, which is in thermal contact with a thermoregulation liquid.

3. Exposure device according to the preceding claim, the thermoregulation liquid receiving evacuation water from the exposure tank(s).

4. An exposure device according to any preceding claim, comprising a first thermoregulation tank (16) and a second thermoregulation tank (17) placed in series.

5. Exposure device according to any one of the preceding claims, comprising a storage tank (11) for water taken from the aquatic system, arranged upstream of the thermoregulation tank (14, 15).

6. Exposure device according to any one of the preceding claims, comprising a water oxygenation system.

7. An exhibition device according to any one of the preceding claims, the exhibition tank(s) (20) each containing at least one cage in which the biological organisms are held.

8. Exhibition device according to any one of the preceding claims, the exhibition tank(s) (20) being a pouring tank, in particular being provided with an outlet arranged in a wall of the exhibition tank.

9. Exposure device according to the preceding claim, the overflow from the exposure tank(s) (20) flowing into a thermoregulation tank (15), in particular into the first thermoregulation tank (15).

10. Exposure device according to any one of the preceding claims, the exposure tank(s) (20) being supplied from the bottom, in particular below the level of liquid which they contain.

11. An exhibition device according to any one of the preceding claims, comprising a lighting system configured to allow the brightness in the exhibition tanks to be modulated.

12. Exhibition device according to the preceding claim, the lighting system comprising one or more light sources, in particular LEDs (light-emitting diodes) and one or more screens in front of the light source(s).

13. Exposure device according to any one of the preceding claims, the physicochemical probe(s) comprising at least one of: temperature probe, conductivity probe, pH probe.

14. An exhibition device according to any one of the preceding claims, a largest dimension of the device (1) being less than 2 m, better still less than 1.8 m, or even less than 1.6 m, even better still less than 1.4 m or 1.2 m, the device being in particular configured to be movable from one place to another near an aquatic system.

15. Use of the exposure device according to any one of the preceding claims for biomonitoring the water quality of an aquatic system.

Images