Body burdens of polybrominated diphenyl ethers in childbearing-aged women at an intensive electronic-waste recycling site in China.

Abstract

This study is the first to investigate PBDE body burden with regard to the concurrent analyses of multiple human matrices, namely milk, placenta, and hair, collected from a group of childbearing-aged women at an electronic waste (e-waste) recycling site to determine the partitioning of PBDEs in these different human matrices and the possible health risks imposed to infants at the e-waste recycling site.
Five sets of milk, placenta, and hair samples were collected from an e-waste site (Taizhou, Zhejiang Province) and a reference site (Lin'an city, Zhejiang Province; 245 km away from Taizhou) in China. The concentrations of total PBDEs in different human tissues were analyzed according to US EPA standard methods.
PBDE body burdens of women from the e-waste site (milk 117 +/- 191, 8.89-457 ng/g fat, placenta 19.5 +/- 29.9, 1.28-72.1 ng/g fat, hair 110 +/- 210, 8.47-486 ng/g dry wt.) showed significantly higher levels than those from the reference site (milk 2.06 +/- 0.94, 1.0-3.56 ng/g fat, placenta 1.02 +/- 0.36, 0.59-1.42 ng/g fat, hair 3.57 +/- 2.03, 1.56-5.61 ng/g dry wt.) and were higher than those reported in other studies, due to e-waste recycling operations, especially open burning. On a dry-weight basis, the following trend was found for PBDE among the samples from Taizhou: hair>milk>placenta. Among the donors, the body burden of an e-waste worker ranked second. Higher brominated BDEs (hepta-BDEs) contributed a significantly greater proportion to total PBDEs in hair of the Taizhou women (20%) than that in milk (2.9%) and in placenta (2.6%). The estimated intake of PBDEs of 6-month-old breastfed infants living at the e-waste site was 572 +/- 839 ng/kg body wt/day, which was 57 times higher than that of infants from the reference site (10.1 +/- 4.60 ng/kg body wt/day). Moreover, the maximum calculated value (2,240 ng/kg body wt/day) exceeded the chronic oral reference dose for penta-BDE (2,000 ng/kg/day) of US EPA.
BDE-47 was the dominant congener accounting for 20-30% in all the individual samples, while higher-brominated congeners, for example, BDE-183 and BDE-190, contributed between 2% and 20%. The presence of hepta-BDE congeners (BDE-181, BDE-190) in hair of the women in Taizhou suggest that thermal degradation of Deca-BDE from the open burning of e-waste may have been their source because these congeners are not found in either Penta-BDE or Octa-BDE technical products. Of the three types of samples analyzed, it was also suspected that hair may be more favorable to higher-brominated compounds which might explain why the hair samples contained the highest total PBDE concentrations and the highest proportion of higher-brominated BDEs (hepta-BDEs).
This study provides evidence that primitive e-waste recycling in China leads to high PBDE body burdens in local residents and can potentially threaten the health of infants.
Control measures should be imposed to minimize the level of pollutants resulting from e-waste processing operations to the environment and to humans. In-depth investigations on epidemiological studies of health impacts caused by e-waste recycling operations should be conducted. It is recommended that further measurements of PBDE levels in local food (e.g., fish, shellfish, dairy products, meat, fruits, and vegetables), dust, air, water, and human specimens be collected from a larger sample size at the e-waste processing site for the determination of human exposure pathways to PBDEs.