RU2593013C1 - Method of detecting pollution of natural fresh water reservoirs with mercury - Google Patents

Abstract

FIELD: ecology.

SUBSTANCE: invention relates to ecology, specifically environmental protection and methods of monitoring state of freshwater by bioindication method for assessment of anthropogenic contamination of natural water bodies with mercury. Method comprises complex determination of contamination of rivers based on evaluation of mercury content in tissues of freshwater bivalve molluscs, water and bottom sediments. Sampling of tested objects, specifically freshwater bivalve molluscs Unio pictorum (ordinary pear shell), water and bottom deposits is performed in vegetation period and biological absorption of toxicant (Kb) is calculated as ratio of mercury content in tissues of molluscs to total content of said metal in water and bottom sediments. If Kb > 0.00002±0.000001, water reservoir is contaminated with mercury.

EFFECT: invention makes it possible to forecast unfavourable toxic state of aquatic ecosystem based on presence of hazardous toxicant in natural water body and can be used in environmental monitoring of contamination of river ecosystem and quality control of river water.

1 cl, 2 tbl, 2 ex

Description

The invention relates to ecology, environmental protection and methods for monitoring the status of fresh water bodies. It can be used to control pollution of water bodies with mercury compounds of various nature.

In the context of vigorous anthropogenic activity, heavy metal pollution of fresh water has become a particularly acute problem, since for them at present there are practically no reliable self-cleaning mechanisms (Mamyrbaev A.A. Toxicology of chromium and its compounds: monograph / A.A. Mamyrbaev. - Aktobe , 2012 .-- 284 p.). Unlike organic pollutants undergoing decomposition processes, metals are only capable of redistribution between the individual components of water systems. These compounds fall into natural waters with industrial effluents containing metal salts and trace amounts of elements, with rainwater filtered through dumps, as well as in the event of accidents of various chemical plants and storage facilities. For underground water, the injection of waste into wells, mines and pits is of great importance as a result of mining.

Currently, two main groups of sources of mercury and its compounds into the environment are considered - natural and man-made (Petrosyan BC Global pollution of the environment with mercury and its compounds / BC Petrosyan. - M .: MNEPU, Avant, 2007. - 320 p .; Skurlatov Yu.I. Introduction to Ecological Chemistry. - M.: Higher School. - 2001. - 269 p.). The main natural sources are the upper mantle of the earth's crust (primarily the products of volcanic eruptions, geo-and hydrothermal activity) (E. Granovsky, Mercury pollution of environmental objects / E.I. Granovsky, K.S. Khasenova, AM Darishcheva, V.A. Frolova // Bull. Environmental mercury pollution and demercurization methods. - Almaty, 2001. - 100 p .; EA Zilov. Hydrobiology and aquatic ecology (organization, functioning and pollution of aquatic ecosystems): textbook. - Irkutsk, 2008. - 236 p.) World ocean (including all types of surface and groundwater), large deposits of mercury-containing rocks (ore belts and zones), individual ore fields.

Anthropogenic sources of mercury are various mercury-containing devices (vacuum gauges, barometers, thermometers, electronics and electrical products (mercury batteries and microbatteries, fluorescent lamps - they contain about 500 tons of metallic mercury in Russia).

The main way mercury enters aquatic ecosystems is with wastewater in the form of homogeneous and colloidal solutions and suspensions. The proportion of the anthropogenic component entering the surface water is about 57 thousand tons, which is 10 times higher than the input from natural sources (G. A. Bogdanovsky. Chemical Ecology / G. A. Bogdanovsky. - M.: Moscow State University Publishing House. - 1994. - 215 p .; Stravinskene E.S. The problem of bioavailability of heavy metals in the environmental monitoring of natural waters / E.S. Stravinskene: abstract of thesis - Krasnoyarsk, 2012. - 34 pp.) Currently, environmental experts Among the toxic metal, a priority group is selected, which includes cadmium th, copper, arsenic, nickel, mercury, lead, zinc and chromium as dangerous for living organisms; of these, mercury, lead, and cadmium are the most toxic (Ecological problems of the Upper Volga: a collective monograph / Under the general editorship of A.I. Kopylov. - Yaroslavl: Publishing House of YaGTU, 2001. - 427 p.). However, mercury pollution of the habitat is becoming increasingly important, which is characterized by high toxicity, a variety of migration forms, the specifics of their conversion in natural conditions, increased redistribution and bioconcentration in the habitat (Akhtyamova G.G., Yanin E.P., Tatsiy Yu. G. Contribution of anthropogenic factor to the pollution of bottom sediments of the Pakhna river basin with mercury. Actual problems of ecology and nature management: a collection of scientific papers. - M., 2011. - P. 22-26).

State of the art

A known method for determining environmental toxicity, based on the study of the test object in the control and experimental samples using as a test object embryos and larvae of sea urchins in sea water. Embryos and larvae of sea urchins for their habitat serve as a natural indicator of the level of technogenic pollution and are highly sensitive to the toxic effect of metals and other toxicants. To test objects in sea water add the studied samples of soil, air, river, drinking or freshwater bottom sediments. Assessment of toxicity is carried out by lethality and the number of developmental anomalies of embryos and larvae compared with the control sample and express toxicity in relative toxic units (RF Patent 2057337).

The disadvantage of this method is the fact that toxicity assessment can only be carried out indirectly, and it is even more difficult to obtain information about the environmental situation in a large region. In this case, it is not possible to determine the pollution by any particular pollutant, without taking into account the influence of others.

A known method of environmental assessment of environmental pollution by heavy metals using wild ungulates. The method is carried out by bioindication of the controlled territory, using as organs of the internal indicators of wild ungulates: muscles, kidneys, liver. The content of heavy metals in them is determined, the results obtained are compared with the maximum permissible levels of heavy metals in food products, by exceeding the values of which they judge the presence of contamination of the territory. The presence of long-term pollution is determined by the excess of the concentration of heavy metals in the kidneys of animals, volley release of mercury and lead is determined by the excess of their concentration in the muscles and liver of animal bioindicators.

The method provides the possibility of a multifaceted assessment of a significant area of the region while reducing labor costs (Method for the environmental assessment of environmental pollution by heavy metals. - Patent RU 266537).

The disadvantage of this method is the need for a large sample of relevant animals and the associated costs of its implementation. In addition, this method cannot be used to detect the content of toxicants in the tissues of aquatic organisms.

Data were obtained on the features of the accumulation of heavy metals such as copper, zinc, lead and cadmium in the body of freshwater bivalve mollusks U. pictorum and A.cygnea. It was revealed that the mollusks studied to the greatest extent accumulate zinc (accumulation coefficient Kd = 547) and lead (Kd = 66) (Solovy G.N., Minakova V.V., Karnaukhova I.V., Pavlovskaya V.V. Comparative study accumulations of heavy metals by bivalve mollusks of the families UNIONIDAE and DREISSENIDAE. - Bulletin of OSU. - No. 6. - 2009. - S. 348-350).

The inhibitory effect of lead and cadmium ions on the level of lysozyme activity of U. pictorum bivalves, which led to the death of the studied organisms on the 12th day, was noted, the level of lysozyme activity significantly decreased from 3 days to 12 (in aquariums with lead ions ( Pb ²⁺ ) and on the 16th day, the level of lysozyme activity decreased from 6-8 days to 16th (in aquariums with cadmium ions (Cd)) (Solovy G.N., Minakova V.V., Karnaukhova IV The influence of heavy metals on the lysozyme activity of freshwater bivalve mollusks of the genera UNIO and ANODONTA. - Bulletin of OSU. - 12. - 2006. - P. 235-237).

Prototype

Closest to the proposed is a method of bioindication using mussels Mytilusedulis of different ages "Method of operational bioindication" (patent RU 2395082). Using this method, the authors studied the features of the accumulation of heavy metals in various mussel organs and some quantitative parameters (the level of valve opening - URS, the amplitude of AMP and the frequency of adduction - ADD of their motor activity. Directly in the reservoir, comparative studies (biotests) of the reactivity of several age-related categories of mussels in response to changing conditions of the aquatic environment: periods of ebb and flow, changes in temperature, salinity, and also under conditions of anthropogenic stress and heavy metals. In general, the general behavior of mollusks turned out to be a fairly plastic indicator that quickly reflects changes in environmental environmental factors and can be used in both acute and chronic pollution.

As a disadvantage of this method, the complexity and multi-stage operations carried out in natural conditions by express methods with some degree of relativity of measurements of physiological parameters of mollusks and possible extrapolation of data should be noted.

The objective of the invention is the development of an effective bio-indicative express method for detecting pollution of natural water bodies with mercury under conditions of increasing anthropogenic impact.

Novelty of invention

For the first time in the process of identifying the degree of pollution of natural water bodies with mercury compounds, “express monitoring of the determination of the presence of mercury in natural water bodies is proposed based on the assessment of the mercury content in the tissues of freshwater bivalves, water and bottom sediments. That will allow predicting the adverse toxic state of the aquatic ecosystem by the presence of a dangerous toxicant in a natural body of water. ”

, где С_м - содержание ртути в тканях моллюсков, С_до - содержание ртути в донных отложениях, С_вода - содержание ртути в воде, и при коэффициенте, превышающем 0,00002±0,000001, судят о загрязнении водоема ртутью.Significant differences in the method for detecting pollution of natural water bodies with mercury are that the test objects, namely freshwater bivalve mollusks Unio pictorum (pearl barley), water and bottom sediments are taken during the growing season and the biological absorption coefficient of the toxicant is calculated by the formula

where C _m is the mercury content in mollusk tissues, C _to is the mercury content in bottom sediments, C _water is the mercury content in water, and when the coefficient exceeds 0.00002 ± 0.000001, the water pollution by mercury is judged.

Technical result

The development of an objective and affordable way to identify zones of contamination by mercury compounds in water bodies that differ in the level of anthropogenic load makes it possible to take into account the processes of migration and redistribution of mercury compounds in fresh water. In the proposed method, each of the indicators is necessary and significant for the implementation of the method.

To achieve a technical result, this method is also proposed in which the analysis of the content of mercury compounds in mollusk tissues, water and bottom sediments is carried out once a year, in the period from mid-July to mid-August. The peculiarity of the sampling time is associated, firstly, with the high physiological and biochemical activity of bivalve mollusks, an increase in their filtering activity, and, as a consequence, an increased concentration of toxicants from the habitat. Considering the ability of mercury compounds to dissolve in lipids and penetrate the biological membranes of hydrobiont cells, concentrating in them and redistributing in vital organs, it is necessary to study the mercury content in the body of bivalve mollusks, since these organisms, being food-type filters, pass large mantle cavities through the mantle cavity volumes of water and accumulate toxicant. For example, ordinary pearl barley passes about 7-10 liters of water through the mantle cavity in 1 hour and, accordingly, accumulates toxicants brought by water masses. Secondly, methylated mercury compounds, namely, they accumulate in living organisms, during this period have increased chemical activity: therefore, it is possible to fix the pollutant in the highest concentration in mollusk tissues, water and upper layers of the bottom sediments only in this short period of time of the year. Due to the unique ability of mercury to a high rate of dissolution in lipids and penetration through biological membranes, followed by bioconcentration in animal tissues, this metal, after the death of hydrobionts, enters the bottom sediments and bottom layers of water in concentrations that are ten times higher than environmental standards, which significantly increases the risk secondary pollution of a natural reservoir. Further, methylated mercury compounds are rapidly converted into inorganic forms of the toxicant and some of them go to the next stages of the biogeochemical cycle - migrating to the aquatic environment (deeper layers of bottom sediments are converted to sulfides) and the atmosphere.

To determine the migration ability of mercury compounds in the aquatic ecosystem, it is necessary to determine the level of mercury in the water mass as well, since water, being a dynamic medium, acts as a link between all components of the aquatic ecosystem (bottom sediments and hydrobionts) and in the case of volley pollution, usually from a man-made source, it is possible to quickly and timely fix a large concentration of the toxicant in the aqueous component. In addition, water plays a leading role in the processes of leaching and dissolution of mercury salts, and, thus, allows to take into account the contribution of the natural sources of this metal to the total toxicant level in a natural body of water.

The third component that must be taken into account when implementing the proposed method is bottom sediments, which play, firstly, a large role in the accumulation of mercury compounds, as they are accumulations of particles of soil, rock, plant, animal residues and clay at the bottom of the reservoir, intensively sorbing heavy metal ions, especially as dynamic as mercury. The sorption effect is enhanced in the presence of clay particles with a diameter of about 20 microns. Secondly, it is important to note that when the temperature conditions in the reservoir and the acidity of the environment change, bottom sediments can be a source of secondary pollution for water and aquatic organisms, introducing a toxicant into the reservoir even in the absence of a polluting source. In addition, mercury in bottom sediments can accumulate over a long period of time, therefore it is possible to determine pollution over a certain time period.

A decrease in the concentration of mercury compounds in water with its subsequent growth in bottom sediments and mollusk tissues indicates the transfer of pollutant to the soil and organisms of bottom hydrobionts. In this regard, often in a chemical analysis of the pollutant content only in water and bottom sediments, a result is recorded that does not correspond to the actual level of toxicant in a natural body of water: therefore, to obtain the most objective complete information about the mercury content in a natural body of water, it is necessary to determine it in all the declared higher components of the aquatic ecosystem: water, bottom sediments, and bivalve mollusk tissues.

In this case, conducting a study more than once a year is not advisable, since the accumulation of a toxicant requires a full cycle of the biochemical and physiological activity of bivalves, to determine the mercury compounds in water there must be an optimum temperature and pH values that are recorded only during the growing season , to determine the pollutant in bottom sediments, the conditions of optimal temperature, pH values and activity of certain groups of bacteria (for example, sulfate utsiruyuschih), which most fully executed during the growing season from mid-July to mid-August.

Disclosure of a method of execution

Water intake and determination of mercury compounds are carried out by standard methods. The data obtained are compared with standard values of mercury in water (MPC) equal to 0.0005 mg / l (CaNPiN 2.1.4.1074-01. MPC standards for impurities in household, drinking and domestic water use. - M., 2001. - 99 from.). If this norm is exceeded, the river section is considered contaminated.

Samples of bottom sediments are taken from a horizon of 0-10 cm with a Paterson grab and frozen; drying in this case is unacceptable due to the high volatility of mercury compounds. The mercury concentration is determined by standard methods, then the obtained data are compared with the “intended” environmental standard (Netherlands), equal to 0.00005 mg / kg (Ecological problems of the Upper Volga: a collective monograph / Under the general editorship of A.I. Kopylov. - Yaroslavl: Publishing House of YaGTU, 2001 .-- 427 p.). Upon receipt of data exceeding environmental standards, a section of the river is considered contaminated.

To study the mercury content in bivalve mollusks, individuals of the mollusk Unio pictorum, which dominates in fresh natural water bodies belonging to the class Bivalvia, from the order Gill (Autobranchia), and the Unionidae family, are used. These organisms belong to the group of submerged forms of macrozoobenthos with a filtration type of nutrition. Passing large volumes of water through the mantle cavity, mollusks filter out phyto- and zooplankton, which they feed on. The age of selected mollusks is about 3-4 years, which is due to the entry of organisms into a period of high physiological activity, increased filtering ability, and, accordingly, increased concentration of substances from the environment.

Three mollusks are selected from each study site, in which the average total concentration of mercury compounds is determined.

Bivalve mollusks are selected from the coastal (littoral) zone of the river and at a depth of about 40-50 cm at the experimental points (areas where it is planned to determine the presence or absence of contamination with mercury compounds) and background ones manually. Background plots are river zones located outside the direct impact of pollution sources far from settlements, industrial centers and agricultural land; usually confined to the headwaters. To obtain samples, the soft body of the mollusks is removed from the shell, dried with filter paper, frozen and stored at -18 ° C.

Determination of the mercury content in the tissues of bivalve mollusks is carried out by standard methods according to GOST 26929-94 “Raw materials and food products” (GOST 26929-94 “Raw materials and food products. Sample preparation. Mineralization to determine the content of toxic elements.” - Interstate standard. - 1994. - 12 p.). The data obtained are compared with standard values of mercury content in animal tissues (MPC) equal to 0.3 mg / kg (SanPiN 42-123-4089-86 Maximum allowable concentrations of heavy metals and arsenic in food raw materials and food products. - No. 4089- 86. - M., 1986).

To identify mercury compounds in the biogeochemical cycle, including bottom hydrobionts, the biological absorption coefficient (Kb) is calculated, which is numerically equal to the ratio of the mercury content in bivalve mollusk tissues to the total content of this metal in bottom sediments and water, since the toxicant is absorbed not only from the soil, but and out of water:

where Kb is the coefficient of biological absorption of mercury by mollusks; With _m - the mercury content in the tissues of mollusks at a specific point in the study (mg / kg); C _to - mercury content in bottom sediments taken from the mollusk intake point (mg / kg); С _water - mercury content in surface water (mg / l).

Calculation Example

The concentration of mercury in water, bottom sediments, and tissues of bivalve mollusks Unio pictorum (common barley) was determined by atomic absorption spectrometry (ACC), the values are shown in table 1.

The biological absorption coefficient (Kb) was calculated by the formula:

where C _m is the mercury content in the tissues of mollusks at a particular point in the study (mg / kg); C _to - mercury content in bottom sediments taken from the mollusk intake point (mg / kg); С _water - mercury content in surface water (mg / l).

For station number 2 "p. Urals in the area of the camp "Dubki" "the calculation was made using the data of table 1:

The obtained coefficient of biological accumulation of KB _{(station No. 2) was} compared with the background coefficient of biological accumulation of KB _(background) :

Thus, the determination of the biological absorption coefficient (Kb) of mercury compounds in mollusk tissues in comparison with its content in the medium (water and bottom sediments) made it possible to determine greater mercury accumulation in Unio pictorum mollusk tissues from station No. 2 “p. Urals in the vicinity of the Dubki camp, "since KB _{(station No. 2)} exceeded KB _{(background) by} 700 times, which indicates, firstly, significant contamination of the study area with mercury compounds, and secondly, the possibility of using this species of mollusks Unio pictorum (pearl barley) as the most informative bio-indicator in assessing the degree of pollution of the aquatic ecosystem by the studied toxicant.

Bivalve mollusks were selected in the background section “Ural-Bolshoy Zabora River” (station No. 1) in July 2011 and in July 2013. Calculation of Kb for this type of bivalve mollusks did not reveal a significant change in value (Table 2), which allows using it as a criterion for determining the pollution of the aquatic environment with mercury compounds and apply the concept of “background coefficient” of mercury absorption by bivalve mollusks.

To calculate the background coefficient, the parameter Kb ± a is used, where Kb is the average background coefficient, and a is the standard deviation. Statistical processing is carried out by standard methods using computer programs EXCEL 2000 (Microsoft, USA). Biological absorption coefficients that differ from the average by more than the standard deviation (Kb ± a) characterize this section of the river as contaminated. For pearl barley, the background biological absorption coefficient was 0.00002 ± 0.000001. Thus, when the biological absorption coefficient exceeds the background coefficient of 0.00002 ± 0.000001, the presence of river pollution with mercury compounds is recorded even if there is no excess of the MPC of mercury in water and bottom sediments.

The following examples were used to clarify the need for a background coefficient.

Example 1. Determination of the concentration of mercury in water and bottom sediments at station No. 2, the Ural River in the vicinity of Dubki camp, showed a 20-fold excess of the content of mercury compounds in bottom sediments relative to the environmental (intended) norm (Table 1). In the water and tissues of the mollusk Unio pictorum (common pearl barley) (Table 1), no excess of the MPC of the toxicant was found. The biological absorption coefficient of Unio pictorum (pearl barley) exceeded the background coefficient by a factor of 700 (Table 2), which indicates a significant accumulation of toxicant in mollusk tissues compared to the background region even in the absence of excess MPC. Thus, the study of water, bottom sediments and tissues of bivalve mollusks allows us to establish the presence of a pollutant in a natural body of water.

Example 2. Analysis of the mercury content in water at the stations “Ural River in the Area of the Water Intake”, “Ural River in the Area of the Road Bridge”, “Ural River in the Area of the Railway Bridge” showed no excess of MPC values for this pollutant in all areas; in bottom sediments, the mercury concentration was exceeded in all zones, the highest was observed for the Ural River station near the Dubki camp: the intended environmental standard was exceeded 900 times (Table 1). For tissue of the mollusk Unio pictorum (pearl barley) there was no excess of MPC, but the background coefficient of biological accumulation was exceeded at all stations under study: at the Ural River in the Water intake area and the Ural River in the area of the Road Bridge stations 40 and 44 times accordingly, at the Ural River in the Zheleznodorozhny Bridge station, 210 times (Table 2). This fact indicates that the accumulation of pollutant in the tissues of aquatic organisms in different zones of the river is not the same, which indicates the possibility of a differentiated assessment of the degree of contamination of natural water bodies with mercury using the biological accumulation coefficient of this heavy metal in the tissues of bivalve mollusks Unio pictorum (common barley).

Despite the fact that no excess of the MPC of mercury in water was found in any of the studied sections of the river, this parameter should be taken into account when assessing the degree of pollution of a natural body of water by the studied pollutant, since water, being a dynamic medium, acts as a link between all components of the aquatic ecosystem and in case of volley contamination, usually coming from a technogenic source, it is possible to quickly and timely fix a large concentration of the toxicant in water.

Thus, a comprehensive study of mercury concentrations in Unio pictorum mollusk tissues, water, and bottom sediments in river sections of different levels of toxic load allows us to identify the most and least favorable zones of the river by this indicator.

The inventive method for detecting river pollution with mercury compounds allows you to objectively assess the effect of this pollutant on hydrobiocenosis by analyzing its content in the tissues of the dominant species of freshwater bivalve mollusks Unio pictorum. This type of mollusks makes it possible to identify pollution of the reservoir with mercury compounds as they accumulate, which indicates the need for its use in indicating the state of natural reservoirs.

All operations from taking mollusks, bottom sediments and water to calculating the result are best done as soon as possible, at once and even within one day.

The inventive method is intended for use in water bodies of cultural, domestic and fishery water use, during planned hydrological studies of the river and its tributaries in the catchment areas, in the work of environmental organizations, and can also be implemented in environmental monitoring of pollution of the river ecosystem and quality control of river water.

Information sources

1. Akhtyamova G.G., Yanin E.P., Tatsiy Yu.G. Contribution of anthropogenic factor to the pollution of bottom sediments of the river basin It smells like mercury. Actual problems of ecology and environmental management: team. scientific labor. - M., 2011 .-- S. 22-26.

2. Bogdanovsky G.A. Chemical Ecology / G.A. Bogdanovsky. - M.: Publishing House of Moscow State University. - 1994 .-- 215 p.

3. GOST 26929-94 “Raw materials and food products. Sample preparation. Mineralization to determine the content of toxic elements. " - Interstate standard. - 1994. - 12 p.

4. Granovsky E.I. Mercury pollution of environmental objects / E.I. Granovsky, K.S. Khasenova, A.M. Darishcheva, V.A. Frolova // Bull. Mercury pollution and methods of demercurization. - Almaty, 2001 .-- 100 s.

5. Zilov EA Hydrobiology and water ecology (organization, functioning and pollution of aquatic ecosystems): textbook. allowance. - Irkutsk, 2008 .-- 307 p.

6. Mamyrbaev A. A. Toxicology of chromium and its compounds: monograph / A.A. Mamyrbaev. - Aktobe, 2012 .-- 284 p.

7. Petrosyan V.S. Global pollution of the environment with mercury and its compounds / B.C. Petrosyan. - M .: MNEPU, Avant, 2007 .-- 320 p.

8. SanPiN 2.1.4.1074-01 Standards for maximum permissible concentrations of impurities in household, drinking, and domestic water. - M., 2001 .-- 99 s.

9. SanPiN 42-123-4089-86 Maximum permissible concentrations of heavy metals and arsenic in food raw materials and food products. - No. 4089-86. - M., 1986

10. Skurlatov Yu.I. Introduction to environmental chemistry. - M .: Higher school. - 2001 .-- 269 p.

11. Solovy G.N. The influence of heavy metals on the lysozyme activity of freshwater bivalve mollusks of the genera UNIO and ANODONTA / G.N. Solovykh, V.V. Minakova, I.V. Karnaukhova. - Bulletin of OSU. - No. 12. - 2006 .-- S. 235-237.

12. Solovy G.N. A comparative study of the accumulation of heavy metals by bivalves of the families UNIONIDAE and DREISSENIDAE / G.N. Solovykh, V.V. Minakova, I.V. Karnaukhova, V.V. Pavlovskaya. - Bulletin of OSU. - No. 6. - 2009 .-- S. 348-350.

13. Stravinskene E.S. The problem of bioavailability of heavy metals in environmental monitoring of natural waters / E.S. Stravinskene: author. diss. - Krasnoyarsk, 2012 .-- 34 p.

14. Ecological problems of the Upper Volga: a collective monograph / Ed. ed. A.I. Kopylova. - Yaroslavl: Publishing House of YSTU, 2001. - 427 p.

Claims (1)

A method for detecting mercury pollution of fresh water bodies of water, including sampling of water, bottom sediments and bivalve mollusks Unio pictorum (pearl barley), characterized in that the sampling of the tested objects, namely freshwater bivalve mollusks Unio pictorum (pearl barley), water and bottom sediments, carried out in the growing season, the calculation of the coefficient of biological absorption of the toxicant is carried out according to the formula

where C _m is the mercury content in mollusk tissues (mg / kg), C _do is the mercury content in bottom sediments (mg / kg), C _water is the mercury content in water (mg / kg), and with a coefficient exceeding 0.00002 ± 0.000001, judged by mercury pollution of the reservoir.