Human blood samples as indicators of occupational exposure to persistent chlorinated hydrocarbons.

The value of using human blood as an indicator of occupational exposure to persistent organochlorine compounds is demonstrated. Blood samples from a total of 35 persons divided into three different groups, with and without exposure to chlorinated hydrocarbons in the work atmosphere, have been investigated by gas chromatography using electron capture detection. It is shown that the group of workers with an occupational exposure to pentachlorobenzene, hexachlorobenzene, heptachlorostyrene and octachlorostyrene had a higher level of these chlorinated hydrocarbons in their blood samples than did the other groups. On the average, the concentration of hexachlorobenzene is about 20 times higher in blood samples from the occupationally exposed workers than from the control group. The level of hexachlorobenzene in blood samples of the control groups is low compared to recent studies of blood samples from the general population in other industrialized countries. Furthermore, the average value obtained for the exposed workers is of the same magnitude as the general population in these industrialized countries.