| Persistent halogenated hydrocarbons(PHHs) are derivatives of hydrocarbons which include some halogen atoms within their chemical structure. These chemicals are generally environmental persistent, bioaccumulative and toxic, causing adverse effects on human being and wildlife. With nearly 30-year rapid development of the electronic-waste(e-waste) dismantling industry and electronics manufacturing, as well as in the past decades as a traditional agriculture province in China, Guangdong province is heavily contaminated by PHHs such as halogenated flame retardants(HFRs), polychlorinated biphenyls(PCBs) and Dichlorodiphenyltrichloroethane(DDT). Despite a number of studies have reported the bioaccumulation of HFRs and PCBs in wildlife from Guangdong province, few data are available on wildlife from areas other than point-source pollution areas(typically e-waste recycling sites and electronics manufacturing and assembling centers). Moreover, all the bioaccumulation studies were almost exclusively performed in aquatic ecocystems, studies on these chemicals in terrestrial ecosystems are scarce. Furthermore, the health effects of PHHs in wildlife from highly polluted areas(e.g., e-waste sites) were not well understood. In the present study, we detected the concentrations of PCBs and several HFRs including ploybrominated diphenyl ethers(PBDEs), decabromodiphenyl ethane(DBDPE), 1,2-bis(2,4,6-tribromophenoxy) ethane(BTBPE) and Dechlorane Plus(DP) in a piscivorous bird, the common kingfisher(Alcedo atthis), from several point source pollution and non-point source pollution areas in Guangdong province, and investigated the spatial distribution and contaminant patterns of PHHs in these birds. Additionally, we determined the concentrations of PHHs and nitrogen(δ15N) and carbon(δ13C) stable isotopes in the muscle of four terrestrial passerine species(Parus major, Copsychus saularis, Pycnonotus sinensis and Pycnonotus jocosus) from the Shimengtai National Nature Reserve(SNNR) in Guangdong province, to investigate the accumulation characteristics and the influencing factors of PHHs in the terrestrial birds. Finally, we explored the associations between the hepatic levels of PHHs and the symptoms of hepatic injury including hepatic oxidative stress, liver function parameters and liver histopathology changes in the birds from e-waste sites.The concentrations of ∑HFRs in the muscle of the kingfishers from the e-waste sites(Qingyuan and Guiyu), the electronics manufacturing and assembling sites(Zengcheng and Huizhou), and the non-point source pollution sites(Heyuan, Meizhou, Jieyang, Enping, Maoming, Yingde, Zhaoqing and Shaoguan) ranged from 2090–125800, 48–1280, 18–470 ng/g lipid weight(lw), respectively. The concentrations of ∑PCBs from the e-waste sites, the electronics manufacturing and assembling sites, and the non-point source pollution sites ranged from 2100–1482000, 60–1500, 39–2990 ng/g lw, respectively. The concentrations of ∑HFRs and ∑PCBs in the birds from the e-waste sites were significantly higher than those from the electronics manufacturing and assembling sites, and these levels were 2–3 orders of magnitude higher than those detected in the kingfishers from the non-point pollution source sites. In addition to the differences in the PHH levels, the contaminant patterns were different among the three types of sampling sites: ∑PBDEs and ∑PCBs were predominant among the PHHs analyzed in the e-waste sites, while ∑DDTs were the major PHHs in the electronics manufacturing and assembling and the non-point source pollution sites, with a higher fraction of ∑PBDEs and ∑PCBs in the electronics manufacturing and assembling sites compared to the non-point source pollution sites. These results suggested that the primitive e-waste recycling and dismantling activities and the concentrated electronics manufacturing and assembling activities not only have caused heavily PBDEs and PCBs pollution in the kingfishers from these areas, but also changed the patterns of PHHs in these birds. For the non-point source pollution sites, a positive correlation between PHHs levels and human population density was observed.The concentrations of ∑DDTs, ∑PCBs, ∑PBDEs, DBDPE, BTBPE and DP in the muscles of four terrestrial passerine birds from the SNNR ranged from 30–5270, 45–1770, 11–340, 2.7–125, 0.02–1.2 and 1.2–104 ng/g lw, respectively. P. major had the highest PHH concentrations compared to the other species, and C. saularis had higher PHH concentrations compared to the two bulbuls(P. sinensis and P. jocosus). Stable isotope data revealed that the δ13C values were significantly different among P. major, C. saulari and the two bulbuls(P. sinensis and P. jocosu), suggesting that diet source is different among the birds. Additionally, the δ15N values were also different among the bird species, indicating the different trophic level of the birds investigated. Furthermore, positive correlations were found between the δ15N values and the concentrations of most of the PHHs. The result suggested the different bioaccumulation potentials of the PHHs among the birds, resulting from the different trophic levels of the birds investigated. Together, the inter-species differences in PHH concentrations and profiles in the present birds could be attributed to the differences in trophic level and diet among these birds.The hepatic concentrations of ∑PBDEs, DBDPE, BTBPE, DP, ∑PCBs, and ∑DDTs in the kingfishers form the Qingyuan e-waste site ranged from 22–2550, 0.1–9.2, nd–0.2, 0.3–55, 790–70600, and 40–390 wet weight(ww), respectively. The concentrations of ∑PBDEs and ∑PCBs were 1–3 orders of magnitude higher than those detected from the reference site. The hepatic concentrations of reactive oxygen species(ROS) and Malondialdehyde(MDA) and the serum levels of total cholesterol(TCH), aspartate aminotransferase(AST) and alkaline phosphatase(ALP) were significantly higher in the kingfishers from the e-waste site compared to the reference site. In contraste, the activities of superoxide dismutase(SOD) and catalase(CAT) in the liver of the kingfishers from the e-waste site were significantly lower than those from the reference site. In addition, the incidence rate of liver histological changes was higher in the kingfishers from the e-waste site when compared to the reference site. Correlation analysis revealed that the hepatic ROS and MDA levels were positively correlated to the hepatic levels of ∑PBDEs and ∑PCBs, but the hepatic activities of SOD and CAT were negatively correlated to the levels of ∑PBDEs and ∑PCBs. These results suggested that the kingfishers from the e-waste site has experienced liver injury(oxidative damage, inflammation and steatosis), which may be associated to the ∑PBDEs and ∑PCBs exposure.The levels of ∑PBDEs, DBDPE, BTBPE, DP, ∑PCBs, and ∑DDTs in the muscle of the light-vented bulbul form the Guiyu e-waste site ranged from 180–33520, 1.7–630, 0.6–39, 4.6–530, 87–7200, and 17–340 ng/g lw, respectively. Except for ∑DDTs, these levels were 1–3 orders of magnitude higher than those from the reference site. Liver weight and hepato-somatic index(HSI) of the birds from the e-waste site were significantly higher than those from the reference site, indicating that the birds from the e-waste site had enlarged liver. Addionally, the HSI values were positively correlated to the levels of ∑PBDEs and ∑PCBs, but were no significantly correlated to the other PHHs. Furthermore, liver histopathological lesions were observed in some of the birds from the e-waste site, which contained significantly higher PHHs levels than those without lesions. |
PDF Full Text Request