MAIN RESULTS

Soil sampling on polluted by superecotoxicants territories

Several methods for dioxin determination in various objects of environment, food substances and technical materials were developed and attested.

The following methods were created:

• The procedure of dioxin-like PCB determination together with PCDD/PCDF in blood samples;
• The procedure of ultra-trace determination of polychlorinated biphenyls in chlorinated pesticides using gas chromatography-high resolution mass spectrometry in the water samples, soil, sediments and biosamples;
• The procedure of polychlorinated biphenyls determination in transformer oils and other oil products;
• The procedure of alkylphenols and chlorophenols determination in water, soils and sediments using gas chromatography-mass spectrometry;
• The procedure of oil, n-alkanes and determination of other oil constituents in water, soils and sediments by gas chromatography-mass spectrometry;
• The procedure of pentachlorophenol trace determination in soils and sediments at low ng/g level;
• The procedure of PCB determination in water by perchlorination and GC-ECD;
• The procedure of DDT and its metabolites, Lindane and HCB determination in water and soil by GC-ECD with GC-MS confirmation;
• The method of survey analysis of organic pollutants in the environment, technical materials and other objects by gas chromatography-mass spectrometry.

The procedure of heavy metals (Pb, Cd, As and Mn) determination in water and soil samples by atomic absorbtion spectrometry was adapted.

Methodology of system approach in GC-MS analysis was developed for complex mixtures of organic compounds. A set of florine-substituted internal standards for multi-component organic analysis of environmental objects was developed.

The Laboratory is accredited by the State Committee of the Russian Federation on standardization, metrology and certification (Governmental Standard of the RF) in November 1993, registered in the List of the System (certificate of the ROSS RU. 0001.511136) for carrying out of the analysis of dioxin, dioxin-like compounds and other pollutants of the environment. The Laboratory takes part in International Qualification Tests.

Water solubility of dioxins was studied and the way was found of the solubility increasing for several orders due to creation of subcritical conditions. It was shown that in subcritical conditions at the presence of iron as catalyst, the process of dioxins dechlorination occurs that points a way for detoxication of heavily polluted soils.

The level and character of dioxin pollution in South Vietnam and some regions of Russia were studied, as well as the ways of dioxin transformation and transferring in the environment. For modeling of ecotoxicants dynamic in the environment a complex research scheme was realized, combining the study of dioxin pollution in the area of ‘hot spots’ (the places with especially high content of dioxins), in the regions, undergone and not undergone the treatment with defoliant during the war, and on the ways of possible distribution of dioxins from ‘hot spots’. It was shown that the profile of congeners of PCDD/PCDF in soil, sediment and biological samples depends on the source of pollution and can serve as indicator of the source of pollution.

According to PCDD/PCDF level and congener profile in soils all polluted territories were ranged into 4 types: 1) with high level of pollution with the initial congener profile typical for ‘orange agent’, 2) the sites of PCDD/PCDF transferring with changed congener profile, 3) the sites treated by defoliants, and 4) control territories, not subjected to the treatment.

On the base of monitoring results on dioxin pollution of the environment and wildlife in the south of Vietnam, the model was developed of ecological fate of 2,3,7,8-TCDD.

An important role of persistent organic pollutants in the ecosystems of Vietnam for formation of negative anthropogenic load on inhabitants was confirmed.

A dioxin pollution of urban territories adjacent to the airport Danang was evaluated, the place strongly polluted with dioxins where previously military base of USA was located, on which operations with ‘Orange Agent’ (OA) were undertaken. Evaluation of dioxin pollution was also done for soils, sediments and biological samples, including river sediments in the north and south of Vietnam. High content of 2,3,7,8-TCDD on the airport territories, adjacent to ‘hot spot’ was determined, the areas within the city subjected to significant pollution by OA were revealed. Factors of bioconcentrating for PCDD and PCDF were determined for freshwater fish in the lake, into which the rain water got from airport territory. Evaluation of the pollution state of urban territories, adjacent to the airport, showed the growth of anthropogenic dioxin load in modern Vietnam. An additional unknown source of dioxins was revealed besides the ‘hot spot’ and anthropogenic sources.

The program of soil monitoring of persistent organic pollutants in the city of Moscow was developed. The studies, carried out during two years confirmed the presence in Moscow soils of significant level of polychlorinated dibenzo-p-dioxins, dibenzofurans, polychlorinated biphenyls, polycyclic aromatic hydrocarbons, chlorinated pesticides, and also alkylphthalates, oil and other organic pollutants. The content of organic pesticides in several soil samples exceeds the allowed level, accepted in Russian Federation and European countries. A special index of hazard degree was calculated for Moscow soils, considering both their concentration and relative toxicity/ According this index the most hazard pollutants in descending order were: PAH, DDT and its metabolites, PCDD/PCDF/PCB, oil.