Polybrominated diphenyl ethers in surface sediments of the Yangtze River Delta: Levels, distribution and potential hydrodynamic influence

A total of 32 surface sediments collected from the Yangtze River Estuary, Hangzhou Bay and the Qiantang River were analyzed for polybrominated diphenyl ethers (PBDEs). The concentrations of summation operatorPBDEs (sum of 12 PBDE congeners without BDE 209) and BDE 209 varied from n.d. to 0.55 and from 0.16 to 94.6 ng/g, respectively. The spatial variability of summation operatorPBDEs concentrations indicated that waste discharge from the urban areas might been the main source of PBDEs in the Yangtze River Delta. BDE 209 was the predominant congener (approximately 90-100%) detected among the 13 congeners, consistent with the fact that technical deca-BDE mixtures are presently the dominant technical PBDE mixtures used in China. Compared to published data acquired from other locales, PBDE congeners with less than four bromines were more abundant in the present study area. The hydrodynamic conditions may likely be a significant factor in dictating the observed levels and congener distribution patterns of PBDEs.     

Bioaccumulation and trophic transfer of polybrominated diphenyl ethers (PBDEs) in biota from the Pearl River Estuary, South China

Two hundred and fifty-four biota samples (four species of invertebrates and ten species of fish) were collected from the Pearl River Estuary between 2005 and 2007 and one hundred and twenty four individual or composite samples were analyzed for polybrominated diphenyl ethers (PBDEs). The concentrations of PBDEs in organisms varied from 6.2 to 208 ng/g lipid weight. This PBDE level was significantly lower than those collected in 2004, showing a decreasing trend of PBDEs in biota in the study area. Trophic magnification factors (TMFs) for nine BDE congeners were calculated with values ranging from 0.78 to 3.0. TMFs of BDE47, 66, 100, 99, 154, and 153 were statistically greater than one, indicating a biomagnifcation potential for these congeners. Significant positive correlations were also found between concentrations of the total PBDEs, BDE28, 47, 66, 100, 99, 154, and153 and lipid content in biota, indicating the that bioconcentration also played an important role in the accumulation of PBDEs. No correlation between trophic level and lipid content was found, suggesting that biomagnification was not the result of lipid content effect but indeed occurred. The concentration ratios of BDE99 to BDE100 were much lower in biota than that in water implying that potential congener-specific biotransformation of PBDEs occurred and influenced the biomagnification of BDE congeners.     

Polybrominated diphenyl ethers (PBDEs) in free-range domestic fowl from an e-waste recycling site in South China: levels, profile and human dietary exposure

To evaluate the status of polybrominated diphenyl ethers (PBDEs) contamination in poultry and sequentially human exposure through consumption of poultry in an e-waste recycling site in South China, two kinds of free-range domestic birds, chicken and duck, were collected and their muscle and liver tissues were analyzed for 16 PBDE congeners. Chicken shows higher PBDE concentrations (summation of 16 PBDE congeners) in both muscle and liver tissues, ranged from 5.7 to 4381 and from 1.5 to 7897 ng/g (lipid weight, the same hereinafter), respectively, compared to duck, ranged from 2.4 to 51 and from 1.9 to 134 ng/g. Different living habitat and feeding habits between the two species might be responsible for this observation. No sex-related differences in PBDE concentrations were found for the two species, while the PBDE concentrations in muscle were higher than those in liver for chicken. The PBDE concentrations in muscle of chicken in the present study were higher than the levels of PBDEs in chicken from other studies reported by far. BDE209 and nona-BDEs were the major congeners in poultry. Comparison of PBDE profiles between birds and environmental matrix implied that the biodebromination of BDE209 might occur in poultry. The intake of PBDEs through consumption of poultry ranges from 7.8 ng/day to 3582 ng/day with a medial 68 ng/day, which is comparable to the calculated values through consumption of all foodstuffs in other studies. The present study suggested that the total dietary PBDEs intake for local residents might be considerably enhanced due to the e-waste recycling activity.     

电化学传感法测定水中亚硝酸盐

借助于简单可控的在线电聚合方法,溴酚蓝被修饰到玻碳电极表面,制备了聚溴酚蓝修饰玻碳电极。实验表明,聚溴酚蓝薄膜对于亚硝酸盐的电化学氧化具有很好的催化作用。经实验优化,聚溴酚蓝膜的最佳厚度为聚合20圈,最佳的检测底液为pH=4.0的0.01 mol/L磷酸盐缓冲溶液。亚硝酸盐在传感器上的电化学氧化是一个双电子双质子参与的过程。在最佳检测条件下,亚硝酸盐的氧化峰电流与其浓度在0.02~109.1μmol/L范围内有良好的线性关系,检测限低至5 nmol/L(S/N=3),所制备的亚硝酸盐传感器线性范围宽、检出限低、稳定性和重现性好、抗干扰能力强,将传感器应用于东湖水样中亚硝酸盐含量的测定,结果令人满意。     

Dechlorane Plus (DP) in air and plants at an electronic waste (e-waste) site in South China

Air and foliage samples (Eucalyptus spp. and Pinus massoniana Lamb.) were collected from e-waste and reference sites in South China and analyzed for Dechlorane Plus (DP) and two dechlorinated DPs. DP concentrations in the air were 13.1-1794 pg/m³ for the e-waste site and 0.47-35.7 pg/m³ for the reference site, suggesting the recycling of e-waste is an important source of DP to the environment. Plant DP, with concentrations of 0.45-51.9 ng/g dry weight at the e-waste site and 0.09-2.46 ng/g at the reference site, exhibited temporal patterns similar to the air DP except for pine needle at the reference site. The air-plant exchange of DP could be described with the two-compartment model. Anti-Cl₁₁ DP was measured in most air and plant samples from the e-waste site. The ratios of anti-Cl₁₁ DP to anti-DP in the air and plants may indicate the preferential uptake of dechlorinated DP by plant compared with DP.     

上海地区霾时气溶胶类型垂直分布的季节变化

采用上海地区2007年1月~2010年11月CALIPSO星载激光雷达Level 2反演资料,对清洁海洋型、沙尘型、大陆污染型、大陆清洁型、污染沙尘型和烟尘型等类型气溶胶垂直分布进行了分析,研究了其季节变化规律.结果表明:霾发生时0~2km高度烟尘型气溶胶出现频率明显高于非霾时,而在2~8km高度,沙尘型、污染沙尘型与大陆污染型明显高于非霾时.0~2km高度春季霾大陆污染型气溶胶出现频率高于其他季节;0~2km夏季污染沙尘型气溶胶与海洋型气溶胶出现频率均高于其他季节,特别是污染沙尘型;秋季霾期间,0~2km高度范围内烟尘型出现频率明显高于2~6km高度;冬季污染沙尘型、烟尘、大陆污染型气溶胶出现频率高于其他季节.     

Polycyclic aromatic hydrocarbons in suspended particulate matter and sediments from the Pearl River Estuary and adjacent coastal areas, China

The spatial distribution, composition, and sources of polycyclic aromatic hydrocarbons (PAHs) in sediments and suspended particulate matter (SPM) from the Pearl River Estuary and adjacent coastal areas were examined. Total PAH concentrations varied from 189 to 637 ng/g in sediments and 422 to 1,850 ng/g in SPM. PAHs were dominated by 5,6-ring compounds in sediments and by 2,3-ring compounds in SPM samples. Assessment of PAH sources suggested that biomass and coal combustion is the major PAH source to the outer part of the estuary sediments and that petroleum combustion is the major PAH source to the inner part of estuary sediments. As for SPM samples, PAH isomer pair ratios indicated multiple (petroleum, petroleum combustion, and biomass and coal combustion) PAH sources, and significant temporal variations could exist for the sources of water column PAHs in the study area. The distribution of perylene in SPM samples indicated that the river was the dominant source of perylene in SPM and that perylene could be taken as an index to assess the contribution of river inflow to the total PAHs in SPM samples. The high concentration of perylene in the sediment was indicative of an in situ biogenic origin.     

Increase of antibiotic resistance genes via horizontal transfer in single- and two-chamber microbial electrolysis cells

Environmental Science and Pollution Research - Microbial electrolysis cells (MECs) have been applied for antibiotic degradation but simultaneously induced antibiotic resistance genes (ARGs), thus...