Assessment of Urban Population Exposure to Trichloroethylene and Tetrachloroethylene by Means of Biological Monitoring

Abstract

Exposure of the general population to trichloroethylene and tetrachloroethylene under normal environmental conditions, achieved with biological monitoring, was assessed, and the possible influence of these compounds via drinking water on the body burden was revealed. A total of 79 subjects with no known solvent exposure was selected, by stratified sampling, from the residents of the city of Zagreb. Trichloroethylene and tetrachloroethylene were determined in blood, and trichloroethanol and trichloroacetic acid were determined in plasma and urine. Drinking water samples were also analyzed for trichloroethylene and tetrachloroethylene. Concentrations of trichloroethylene and tetrachloroethylene in blood, trichloroacetic acid in plasma, trichloroacetic acid in urine, trichloroethylene in drinking water, and tetrachloroethylene in drinking water were as follows: < 0.015 to 0.090 μg/l, < 0.010 to 0.239 μg/l, 8.6 to 148.1 μg/l, 1.67 to 102.3 μg/24 h, < 0.05 to 22.93 μg/l, and 0.21 to 7.80 μg/l, respectively. The variation in all results presented is probably a reflection of different environmental contamination with trichloroethylene and tetrachloroethylene in the different city areas. Correlation analyses revealed significant relationships between trichloroethylene and tetrachloroethylene in blood (r = .402, p = .0004); trichloroacetic acid in urine and in plasma (r = .522, p = .0000); and trichloroethylene and tetrachloroethylene in drinking water (r = .800, p = .0000). A division of all parameters into a subgroup (n = 58), taking drinking water concentrations of trichloroethylene above 3 μg/l as a basis, demonstrated the same significant relationships as mentioned above. Significant correlations, however, appeared between both In trichloroethylene and In tetrachloroethylene in drinking water, compared with In trichloroacetic acid in plasma and urine, which could be a result of the influence of contaminated drinking water on body burden.