Method of determining pollution water body using hydrobionts

FIELD: ecological monitoring of water bodies.

SUBSTANCE: bio-testing is done directly in the water body using hydrobionts, not adapted to the water medium under test. The hydrobionts are put in a water permeable container.

EFFECT: consideration of the possibility of determining the quality of water in water bodies during testing and obtaining results which reflect the real ecological condition.

2 tbl

 

The invention "method for determining the contamination of a water body using hydrobionts" relates to the field of environmental monitoring of water objects.

The existing system of control of water pollution, based on the determination of analytical methods maximum permissible concentrations of individual substances and health indicators, does not ensure the preservation of the environmental health of water bodies due to several factors: lack of quantitative analytical methods for the determination of all the toxic compounds contained in the composition of the effluent; heterogeneous nature of the interaction of individual components in the mixture; secondarily formed by the connections that can be more toxic than the analyzed original substance. In addition, the identification of a large number of separate indicators not addressed the issue of the degree of risk to aquatic biocenoses of pollutants in water bodies with wastewater.

All these circumstances have necessitated the development of integrated control methods of natural and waste water, allowing to evaluate the possible danger of those or other sources of contamination to aquatic flora and fauna. The most effective means to meet these objectives, is the biota of the aims, with the help of which you can install the toxic effects of contaminated water on biological objects.

Biotesting - determination of the degree of survival of laboratory organisms in a given test environment.

Our country has developed more than 40 bioassay techniques and their modifications. Detailed description of the main of them is given in the book "Methods of biotesting of water" [1]. Developed Methodological guidance on biotesting RD 118-02-90, which encompasses all the stages of Toxicological control of wastewater and water quality control ponds and watercourses (natural waters) methods of biotesting using as test objects crustaceans, algae and fish [2]. All of these works biotesting is proposed to carry out in laboratory conditions with the removal of water from the water bodies and the use of animals placed in vessels of the type aquariums.

Most effective for assessing water quality control sections is a classic Biotest based on the registration of survival and fecundity of Daphnia, which are sensitive to a wide range of toxic substances of different classes of chemical compounds.

A prototype of this invention is the article "a Method for biological testing using Daphnia" [3].

Disadvantages laboratory bi is testing due to the impossibility of creating conditions identical to natural. The percentage errors are significant, especially if the test is subjected to the pollution of natural water. Than more toxic aqueous medium, the smaller the percentage error. I.e. the classical test is suitable only for wastewater.

Tests in laboratory conditions leads to errors due to:

1. Changes in water quality over time.

2. Aquarium cannot take account of possible changes in water quality after sampling due to new portions of pollutants.

3. A species can adapt to the conditions of the test.

To avoid error due to adaptation of aquatic organisms to contaminants and a large amount of time between sampling and testing are encouraged to biotesting directly into a water body, i.e. a method of "reverse" biotesting, when the animals are placed in the test environment, without transferring water samples in the laboratory. When transferring water samples in the laboratory, it is removed from the natural complex, and deprived of all possible factors which influence the process of transformation of contaminants in nature. Device for biotesting in the natural aquatic environment in the literature are not given.

For biological testing device in use, different is seesa fact, what is the purpose of biotesting of water bodies in conditions as close to natural, it consists of a container that represents the camera, made of permeable material (mill gas No. 72-76), mounted on a rigid frame made of corrosion-resistant wire can be installed to the desired depth by means of a cord, cargo and float.

The device must meet the following requirements:

1. To have sufficient spatial volume for the existence of the test organisms.

2. The permeability of the walls of algae, bacteria and dissolved nutrients.

3. Ease of manufacture.

4. Corrosion resistance.

5. The availability of materials.

As test objects can be used:

1. Classical laboratory cultures of Daphnia maqna Sfraus, Daphnia pulex De Geer - grown in accordance with the instructions RD - 118 [2].

2. Regional dominant, preferably related to classical laboratory species.

3. Dominant and mass species from among the inhabitants of the tested reservoir.

In the case of test objects under # 2 and # 3 reservation "overexposure" of individuals in laboratory conditions (in aquariums) to obtain authentic to test the water culture. The optimal effect is confirmed when using the years of second generation individuals, regional Cladocera Daphnia cucbafa Sars, Daphnia louqispiuc Meiller, Cerioclaphuia pulcyella Sars, Scapholeberis mucrohafa Muller and others, bred in laboratory conditions.

When testing a certain number of laboratory Daphnia (for example, 13 pieces) are placed in the container and fall into the water at a certain depth. Conducted periodic visual observation of the condition of organisms - the number of dead individuals, locomotor activity, the emergence of the offspring.

Water quality assessment is performed on the reactions of the test object on the survival, reproduction and immobilization (loss of motor activity)(table 1).

Table 1

Quality assessment of water on the reactions of the test object
GradePollution degreeThe saprobity indexThe response of test organisms in the container (No. 1, 2, 3 - the 7 day)
1Net1,0Immobilization of up to 2%. Parthenogenesis.
2Moderately clean1,0-1,5Immobilization of up to 10-20%. Parthenogenesis. Partial sexual reproduction.
3Moderately polluted1.5 to 2.5Immobilization of up to 70-80%. Sexual reproduced the interview. Immobilization evenly stretched.
4Contaminated2,5-3,5Death - 2-3 days
5Dirty3,5-4,0Death - 1 day
6Very dirty4,0Lethal - 15 min - 1 hour

The proposed method was tested in field conditions during the examination of waters of the rivers Volga, Kama and Mesh. Results on some of the points presented in table 2.

RCAM about Atabaev, depth 8 m
Table 2

The results of biological testing of water bodies
No. stationStation nameSurvival,%Water quality assessment
1 hour1 day2 days3 days4 days6 daysGradePollution degreeThe saprobity index
1Mouth rmesa, (direction) depth 4 m10005dirty3,5-4,0
210010092777777+2moderately clean1,0-1,5
3Merging currents rmesa and Kama, depth 6 m1007762463131+3moderately polluted1.5 to 2.5
4Old channel RCAM about Islands arrow Drilling, depth 4 m06very dirty4,0
5Channel Volga river near Kurilovo, depth 13 m10010046311515+3moderately polluted1.5 to 2.5
6Shallow water along the section of Atabaev-Kurilovo, depth 3 m100100100100100+100+1net1,0
73 km from No. 6, depth 3.5 m100100100100 100100+1net1,0
8Old channel RCAM about Laishevo, depth 7 m06very dirty4,0
9The confluence of the Volga and the Kama, depth 10 m100383823804contaminated2,5-3,5
+the appearance of the offspring

According to the results of biological testing has determined particularly contaminated zone in paragraphs 1, 4, 8.

In paragraph 8 of hydrochemical indicators of exceedance of MPC is not detected. But in the study of bottom soil defined γ-background isotope cesium-137, which reaches 51,8 Bq/kg in Addition, the fish Kamsko-Ustinsky ples have a high content of zinc and copper, and a very high amount of Nickel to 90.4 mg/kg, 180,8 times the MAC.

The proposed method of determining the contamination of water bodies with the use of aquatic organisms has several advantages compared with prototype:

1. The results obtained reflect the real environmental situation in the inspection zone, associated not only with the presence of certain pollutants, but with environmental factors (temperature, nutrient availability, oxygen content, pH and the like).

2. Take into account the possibility of changes in water quality in a water body in the process of testing.

3. Reveals the impact of unexpected factors, such as radioactivity.

4. The simplicity of the experiment.

Literature

1. Methods of biotesting of water. Edited by Krainykovo A.N. Branch of the Institute of chem. physics, USSR Academy of Sciences, Chernogolovka, 1988, 122 S.

2. Methodological guidance on biotesting of water. RD 118-02-90 State. the Committee of the USSR for nature protection, Moscow, 1990, 71 S.

3. Isakov E.F., Kolosova L.V. Method of biotesting using dafny//Sat. Methods of biotesting. Branch of the Institute of chem. physics, USSR Academy of Sciences, Chernogolovka, 1988, p.50-57.

The method for determining the contamination of the water body with the use of aquatic organisms for their survival, fecundity and offspring, characterized in that conduct testing of water directly into a water body using unadapted to test the water hydrobionts, placed in a permeable container.



 

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