Risk Factors for Environmental Pollution with Dioxin-Containing Compounds

Abstract

Introduction. It has been demonstrated that the use of 2,4-D herbicide contaminates the environment with polychlorinated compounds, including dioxins. Additional risk factors for population health and the environment include climatic conditions of Siberia, processes of translocation of compounds from soil to plants, their ability to reach the human body along trophic chains and to have a toxic effect. The objective of this study was to analyze the behavior of the 2,4-D herbicide and dioxins in the environment and to justify health risk factors. Materials and methods. We used the method of gas chromatography-mass spectrometry that combines high efficiency of separation of impurities, the possibility of determining their molecular composition, selectivity of recording, and high sensitivity. We used a chromatographic method to determine residual amounts of the 2,4-dichlorophenoxyacetic acid amine salt (2,4-D) in soil, feed, and food of plant and animal origin. The calculation of average and statistical errors of indicators was performed using t-test in MS Excel. Results. Contamination of water of open reservoirs of the Irkutsk Region with the 2,4-D herbicide amine salt was found in concentrations as high as 7.7 μg/L with a positive sample count of 49%. In spring and summer, the water of open reservoirs is also polluted. In soils, the 2,4-D amine salt is immobile, concentrated in the surface layer at the level of 0.42–0.37 mg/kg. The maximum total soil concentration of dioxins reached 1,479 ng/kg exceeding the maximum permissible soil concentration of dioxins by 306 times. The maximum concentration of dioxins in feed was found at the end of the growing season (317–322 ng/kg). Dioxins accumulate in fat-containing food; thus, measured dioxin concentrations in butter averaged 680.6 ng/kg demonstrating a 10-fold excess of the permissible level. The estimated daily intake of dioxins with food can be as high as 26.2 pg/kg, which is 2.6 times higher than the permissible daily dose. We conducted the environmental and medico-hygienic analysis of outcomes of using the effective herbicide that poses a serious danger to human health due to the possibility of dioxin formation. We identified risk factors and substantiated the daily dose of dioxins for humans as a temporary value.