Introduction. Landfills of production and consumption waste exist everywhere. Their operation is closely related to unwanted emissions and/or discharges of dioxins. The processes of transfer of these chemicals by air and water flow outside sanitary zones, inclusion in trophic chains, bioaccumulation and overcumulation can contribute to the launch of a toxic process when low subtoxic doses are contained in the medium. It is especially important to take this into account for agro-industrial and residential regions.
The study aims to assess the dioxin pollution of the environment outside the sanitary zone of the solid waste landfill of production and consumption "Lesnaya" (landfill "Lesnaya") by initial (screening) studies of the expected risk to public health.
Materials and methods. Experts characterized dioxin contamination by concentrations of compounds toxic to humans in specially prepared samples, as well as indicators of general toxicity (WHO-TEQ 05). The researchers obtained samples from the surface layers of soil and animal carcasses representing successive generations (groupings) of the winter and summer seasons of the natural population of the bank vole (Clethrionomys glareolus). Concentrations of related substances were measured by high-resolution chromatography-mass spectrometry.
Results. All samples contained dioxins. The good comparability of the profiles of congeners of these substances in soil samples and animal tissues testifies to the general history of their origin, as well as the formation of conditions in the environment for the almost continuous action of small doses of mixtures of these substances on the inhabitants. In soil samples, the values of the WHO-TEQ 05 index were significantly less than the hygienic standard. In animal tissues, concentrations of congeners characterized by pronounced hormone-like toxicity, teratogenic, embryotoxic and carcinogenic properties, primarily 2,3,7,8-tetrachlorodibenzo-p-dioxin, were very high.
Conclusions. The consequences of prolonged exposure to the local natural population of the bank vole of small doses of dioxins in conditions of environmental pollution outside the sanitary zone of the Lesnaya landfill were characterized by the accumulation in their tissues of toxicants with hormone-like properties capable of triggering the mechanisms of formation and development of the toxic process at any concentrations. The scientific and practical significance of the obtained result is determined by the prospects for creating a methodological technique based on it to solve the problem of initial (screening) assessment of the risk to public health, namely the danger of low concentrations (doses) of dioxins polluting the environment.
