DERMAL PENETRATION OF PESTICIDES AND POLYCHLORINATED BIPHENYLS FROM HOUSE DUST.

This study demonstrated that MatTek’s EpiDerm in vitro human skin tissue equivalents were the most in vivo-like for performing percutaneous penetration experiments in vitro. Indoor contamination has been rated as a high environmental risk, as people living in industrialized countries spend about 80-90% of their individual live time indoors. Several epidemiological studies showed a link between the application of pesticides indoors and diseases like leukemia and lymphoid cancer. House dust is an important indicator of indoor contamination regarding semi volatile and nonvolatile compounds. It can be assumed that it also serves as an important pathway of human exposure to environmental xenobiotics, as it might contain high concentrations of endocrine disrupting pesticides as well as polychlorinated biphenyls. The levels, sources and distribution of xenobiotics in house dust have been examined in several studies. The main pathways of exposure, i.e. via skin, digestive system and respiratory tract, have not yet been investigated. This study by researchers at Carl-von-Ossietzky University of Oldenburg (Germany) examined the percutaneous absorption of eight common pesticides in house dust (PCP, DDT, lindane, methoxychlor, propoxur, chlorpyrifos, permethrin and piperonyl butoxide) and of six polychlorinated biphenyls (PCB 28, 52, 101, 138, 153, 180). They are present in house dust in concentrations up to some hundred milligrams per kilogram (Table 1). The main focus of the study is to determine the percutaneous penetration of the pesticides and PCB mentioned above and the effect of surfactants on the penetration. House dust may contain some ‰ of surfactants (mainly detergents) (Table 2). Average concentrations are about 20 mg/kg for the sum of cationic surfactants, 110 mg/kg for the sum of anionic and 1600 mg/kg for the sum of nonionic surfactants. Skin vs. Reconstructed Human Epidermis: The use of reconstructed epidermis is a suitable method to minimize the variation between different skin slices. Artificial epidermis like MatTek EpiDerm EPI-606, SkinEthic and others have been proved to have a tissue architecture and a lipid composition similar to human skin. The dermal penetration rates are quite similar, even though there are still some differences (artificial skin tends to have higher penetration rates than original skin). Up to now, the MatTek EpiDerm EPI-606 seems to be the most favorable product available for shipping to Germany.

Chlorpyrifos, DDT, Dermal penetration, EPI-606, Epiderm, Ethanol, Franz diffusion cells, House dust, Leukemia, Lindane, Lipophilic compounds, Lymphoid cancer, Methoxychlor, PCB 101, PCB 138, PCB 153, PCB 180, PCB 28, PCB 52, PCP, Percutaneous absorption, Percutaneous penetration, Permethrin, Pesticides, Piperonyl butoxide, Propoxur, Reconstructed human epidermis, Respiratory tract, SkinEthic, Surfactants, Triton X-100, Tween 80, Xenobiotics

Chlorpyrifos, DDT, Lindane, Methoxychlor, PCB sum, Pentachlorophenol (PCP), Permethrin, Piperonyl butoxide (PBO), Propoxur