Health risk assessment of background PCDD/F exposure levels in Kocaeli, Turkey.

An estimation and assessment of the polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo furans (PCDD/Fs) exposure levels for the people living in Kocaeli, the most industrialized area of Turkey, are presented. The information is based on the results of PCDD/F analyses in the samples collected from various environmental media and the multimedia exposure assessment methodology. Exposure scenarios were constructed on a site-specific basis by combining the exposure pathways appropriate to the area, and the activity patterns of the people living in Kocaeli. The model showed that the exposure levels of PCDD/Fs were in the range of 3.7-13.1 pg I-TEQ.kg-1 bw for adult receptors, which are higher than the recommended TDI value of 2 pg TEQ.kg-1 bw. The PCDD/F intakes for rural receptors were estimated to be three times higher than those for urban and semi-urban receptors due mainly to the consumption of locally grown foods. The assessment of the contributions of various exposure pathways to the total exposure and the sensitivity analysis performed based on a probabilistic approach indicated that PCDD/F intakes for adult receptors are directly proportional to the locally grown fraction of plant groups consumed.