Potential risk of organochlorine regulation limits in Brazilian soils

Brazil is a major food exporter and consequently a major consumer of pesticides. In the environmental legislation for soil quality maintenance, there are maximum limits allowed for only 8 organochlorine pesticides. In this sense, the aim of the study was to evaluate the potential risk to human health of the regulation limits to agricultural, residential, and industrial soils for the eight organochlorines listed in the legislation. The risk assessment model proposed by the USEPA was used, considering the oral and dermal routes for the non-carcinogenic risk and oral, dermal, and inhalation routes for the carcinogenic risk. The Hazard Index (HI) and the total carcinogenic risk (TCR) were evaluated for the organochlorines individually and their sum. The HI for children of dichloro-diphenyl-dichloroethane (DDD) and the sum of the eight organochlorines were greater than 1, when considering the regulation limits for residential and industrial soils. There was no potential non-carcinogenic and carcinogenic risk for adults, nor risk using limits for agricultural soils. These results demonstrate that the limits provided for in the legislation must be revised for some chemical substances (e.g., DDD), and those studies must be stimulated to predict the toxicological effects of the mixture of contaminants.