PCB-blood levels in teachers, working in PCB-contaminated schools

In order to get more information about potential health hazards due to indo or air PCBs the present study investigated the PCB indoor concentration in schools as well as the blood levels of 6 PCB-indicator congeners in teacher s from these schools. 151 teachers (78 male and 73 female; mean age 48 year s) from 3 contaminated and 2 control schools participated in the study. Max imal indoor air values for total PCBs (6 PCB-indicator congeners times 5) i n schools ranged from 1587 to 10655 ng/m(3). Blood analyses indicated an in crease in mean PCB 28 level from 0.036 (control group) to 0.098 mu g/l in t eachers from a school with heavy contamination of low chlorinated PCB. But there was no significant increase of PCB 138, 153 and 180 in blood above th e normal background concentrations in any of the contaminated schools (mean values of all groups: PCB 138 = 0.66, 153 = 0.95, 180 = 0.70 mu g/l blood) . The results of blood analyses and additional toxicokinetic calculations s uggested that inhalative PCB-uptake in the most contaminated schools caused a minor increase above mean background-PCB concentrations in blood. In con clusion, despite high PCB indoor air levels in schools, there was only a mo derate increase in blood concentrations of teachers, mainly due to congener s with low chlorination (PCB 28 to PCB 101). (C) 2000 Elsevier Science Ltd. All rights reserved.