Modeling of aggregated exposure to chemical substances of biological origin for various types of water use in case of priority cyanotoxins

Abstract

Objective. To assess the exposure on the population caused by the content of priority cyanotoxins in drinking and recreational waters, health risks associated with their complex chronic intake, and scientifically substantiate methodological approaches to modeling the conditions of aggregated exposure of chemical substances of biological origin for various types of water use.Materials and methods. The study analyzed 313 samples of drinking and recreational water for the content of priority cyanotoxins (cylindrospermopsin and microcystin-LR). Aggregated doses were calculated for their intake into the organism of different population groups by drinking, domestic and recreational water use, taking into account multiple ways of intake.Results. Aggregated average daily doses under chronic exposure for drinking, domestic and recreational water use, taking into account oral and dermal ways of exposure under the worst-case scenario, for cylindrospermopsin ranged from 1, 58 x 10-6 mg/(kg x day) (adults) to 3.62 x 10-6 mg/(kg x day) (children under 6 years of age) for cylindrospermopsin and from 4.24 x 10-6 mg/(kg x day) (adults) to 9.00 x 10-6 mg/(kg x day) (children 6-18 years of age) for microcystin-LR.Conclusion. Aggregated average daily doses with chronic exposure to microcystin-LR and cylindrospermopsin under the worst-case scenario of drinking, domestic and recreational water use do not exceed reference doses for all population groups, including vulnerable one (children). The main contribution to the aggregated average daily intake of cyanotoxins for realistic scenarios is made by drinking and domestic water use, oral route of intake.The proposed methodological approaches of modeling of aggregated exposure by multiple ways of exposure to chemicals of biological origin, taking into account different types of water use and seasonality of exposure can be used for building an evidence base for substantiate the hygienic standards and criteria for assessing health risks associated with chemical factor of biological origin.