Pbdes Contamination In Taizhou, Zhejiang,and Body Burden Of Pbdes In Residents

As a class of ubiquitous pollutants, polybrominated diphenyl ethers (PBDEs) have received much attention due to their bioaccumulation and extensive toxicity. The unregulated e-waste recycling treatment in some areas has led to the release of various hazardous chemicals into nearby surrounding, of which PBDEs is one class. Taizhou in Zhejiang Province is one of the largest e-waste recycling areas in China, where existed serious PBDEs contamination. However, there is little data on the impact of PBDEs releasing to the surrounding. Furthermore, the body burden and the potential health risks to local residents are not clear. To solve these problems, this study undertook the following work:(1) To study the contamination and the transport pattern of PBDEs in short-range scale, Cinnamomum camphora leaves were collected from the first disassemble e-waste place Mukeng Village as the centre and ten concentric circles. Variance in∑PBDEs concentrations in the leaves showed that PBDEs from the e-waste recycling area diffused into the surrounding regions and resulted in a halo of PBDEs contamination, at least 74 km in radius. The attenuation of∑PBDEs in the diffusing process fitted in log-linear regression. The difference in the attenuating slopes of linear equations among different directions can be explained by terrain and wind direction. The attenuation of PBDEs congeners also fitted well in log-linear regression. The findings that similar attenuating slopes and characteristic travel distance among congeners suggest that the transport behavior of lower brominated congeners might not differ from that of higher brominated congeners in short-range scale.(2) Semen and blood samples were respectively collected from the fertility clinic at Reproductive Health Center of Taizhou Hospital and clinical laboratory of Taizhou Hospital. These samples were used to study the male reproductive health risk. All the pooled samples of semen and blood were detected with PBDEs. BDE-209 was the dominant congener in both semen and blood, which is consistent with the local PBDEs contamination background. Earlier study showed the local PBDEs contamination was mostly come from BDE-209. Comparing with blood samples, the percentage of lower brominated congeners in semen samples was much higher than that in blood samples, while the trend of higher brominated congeners was reversed in the two matrixes. The concentrations of BDE-28, 47, 99, 100 and 154 in semen samples were much higher than those in blood samples, while the concentrations of BDE-153, 183, 197, 203, 207 and 208 in semen samples were much lower than those in blood samples. There are no significant relationships between the concentrations of∑PBDEs and individual congeners in semen and blood samples. Our results suggest that PBDEs could enter into semen as other Persistent Organic Pollutants (POPs) contaminants and the high pollution burden of PBDEs in semen samples should be concerned. Fuethermore, similar concentrations of PBDEs in semen and blood samples showed semen could also be used to study PBDEs burden in human.(3) To study the pollutant exposure and pollution burden during fetal period, we collected paired cord blood and placenta samples from Wenxi hospitals. PBDEs were detected in all the samples. The concentrations in cord blood samples were much lower than in placenta samples. BDE-209 was the dominant congener in most samples, which was also consistent with the contamination background of PBDEs in this region. Results showed that the proportion of BDE-28 and BDE-47 in cord blood samples was much higher than that in placenta. Compared with lower brominated congeners, the higher brominated congeners were prevented by placenta more effectively. There is no significant relationship of∑PBDEs concentrations between placenta and cord blood samples. Nevertheless, the concentration of BDE-47 and BDE-153 in cord blood samples had positive relationship with those in placenta samples respectively.In summary, this study showed that e-waste recycling has been causing serious pollution of PBDEs on local environment, and has influenced the whole region of Taizhou. The findings that the transport patterns of PBDEs were different between short-range scale and long-range scale suggested that the transport behavior of lower brominated congeners might not differ from that of higher brominated congeners in short-range scale.This study first time detected the existence of PBDEs in human semen samples, which suggested that PBDEs could enter into the human semen. The high concentration of PBDEs in semen samples caused the concern of male reproductive health. The similar concentrations of PBDEs in semen and blood samples showed semen could also be used to detect PBDEs burden in human. PBDEs were detected in all the paired samples of cord blood and placenta, and BDE-209 was the dominate congener in the two matrixes. The data of PBDEs from paired cord blood and placenta samples implied that the local fetus health were worth to concern. The different distribution of brominated congeners in cord blood samples and placenta samples showed that there may be placental barrier effect which could prevent the higher brominated congeners more effectively. Anyway, the transfer and the metabolism of PBDEs from mother to child deserve further research.