Field validation of antioxidant enzyme biomarkers in mussels (Perna viridis) and clams (Ruditapes philippinarum) transplanted in Hong Kong coastal waters

Green-lipped mussels, Perna viridis, and Manila clams, Ruditapes philippinarum were sourced from “clean” sites in the Hong Kong region, depurated in a laboratory using uncontaminated filtered seawater for 8 days, and transplanted to a suspected gradient of chemically polluted sites in Hong Kong. After 14- and 28-days of field exposure, several antioxidant parameters including glutathione S transferase (GST), catalase (CAT), glutathione peroxidase (GPx), and glutathione (GSH) were quantified in gill and hepatopancreas tissues. Whole body tissue concentrations of polycyclic aromatic hydrocarbons (PAHs), petroleum hydrocarbons (PHCs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCs) were determined in pooled site samples. Chemical analyses indicated that: (a) clams had higher levels of PAHs, PHCs, DDTs and PCBs, whereas mussels had higher hexachlorocyclohexane (HCHs) and there was no difference between species for dieldrin and remaining OCs; (b) Kat O should not be continued as a “clean” reference site for Hong Kong, because of the levels of contaminants measured and (c) PAH concentrations in the current survey were similar to those previously measured. Toxicological conclusions were: (a) antioxidant responses were different between species; (b) CAT and GST have highest utility in clams for field use in Hong Kong, whereas CAT in both gill and hepatopancreas tissue showed most potential in mussels; (c) significant induction of antioxidant responses over day 0 (excluding GPx in both tissues, and GST in mussel hepatic tissue); (d) groups of contaminants do not consistently induce antioxidant responses and (e) organochlorines and PCBs correlated significantly with CAT and GST in clam hepatopancreas and with CAT in mussel gill and hepatic tissue. Multivariate statistical techniques indicated little relationship between the site patterns for antioxidant responses and the contaminant gradients identified in body burden analysis.     

加速溶剂萃取-气相色谱/气相色谱-质谱法测定土壤中7种多氯联苯

建立了土壤样品中7种多氯联苯(PCB 28、PCB 52、PCB 101、PCB 118、PCB 138、PCB 153、PCB 180)的分析方法。土壤样品通过加速溶剂萃取、磺化法结合Florisil固相萃取小柱净化、电子捕获检测器气相色谱分析测定,并结合气相色谱-质谱进一步确证。结果表明,方法回收率为80.06%～100.28%,相对标准偏差(RSD,n=6)为1.01%～6.28%,检出限为0.15～0.50μg/kg。用优化的方法测定复杂基质的土壤样品中多氯联苯,具有提取效率高、净化效果好、结果准确可靠、对环境污染小等优点。     

Seasonal variation of polychlorinated biphenyl concentrations in the southern part of the Baltic Sea

The impact of seasonal fluctuations in forcing factors such as atmospheric concentration, temperature, and biological productivity on the concentration of polychlorinated biphenyls (PCBs) in the surface water of the southern part of the Baltic Sea was investigated. Water samples were collected on eight cruises over 2 years. A clear seasonal variability in dissolved PCB concentrations was observed with higher levels in summer than in winter and spring. This was attributed to changes in atmospheric concentrations and water temperature, based on measurements showing the PCB levels in the atmosphere and surface water to be close to a partitioning equilibrium. Concentrations in the suspended particulate material (SPM) fraction were also variable, and when the quotient of the organic carbon normalised concentration in SPM and the dissolved concentration was calculated (i.e., the bioaccumulation factor (BAF)), a seasonal pattern was observed which was consistent with kinetic limitations on partitioning into particles caused by plankton growth. However, seasonal variability in the partitioning properties of the SPM may also contribute to this variability.     

ANAEROBIC DECHLORINATION OF PCBs IN SEDIMENTS OF KINNICKINNIC RIVER, WISCONSIN

1 INTRODUCTION Polychlorinated biphenyls (PCBs) have been used for several decades in a variety of industrial applications such as for transformers, capacitors, and hydraulic fluids (Rachdawong and Christensen, 1997). Because of their stability and desirable hydraulic and dielectric properties, PCBs were used extensively. However, later it became clear that they can be toxic and can have deleterious reproductive effects on biota and humans. They may also display dioxin-like toxicity…     

Enrichment of organochlorine contaminants in the sea surface microlayer: An organic carbon-driven process

Over 50 seawater samples from two different sites—Barcelona (Spain) and Banyuls-sur-Mer (France)—were analyzed in order to study the extent and postulate the processes driving the enrichment of hydrophobic organic pollutants in the sea surface microlayer (SML). A number of individual polychlorinated biphenyl (PCB) congeners (41) were measured to study their partitioning between the particulate (fraction > 0.7 μm) and the dissolved + colloidal phases (fraction < 0.7 μm), with the latter being differentiated into estimated dissolved and colloidal phases. In addition, several organochlorine pesticides were also measured, namely, HCB, α-HCH, γ-HCH, 4,4′-DDE, 4,4′-DDD and 4,4′-DDT. The presence of PCB congener profiles found in the SML suggests a dynamic coupling with the atmosphere in Banyuls sampling site, whereas offshore Barcelona the presence of highly chlorinated congeners was due to persistent sediment resuspension. The average PCB concentration in the SML dissolved + colloidal phase were higher in Banyuls (7.8 ng L^{− 1}) than in Barcelona (3.6 ng L^{− 1}) samples, but in the particulate phase concentrations were higher in Barcelona (3.2 ng L^{− 1}) to that of Banyuls (1.4 ng L^{− 1}). However, PCB concentrations in the SML generally also showed large variability. Enrichment factors of PCBs and other organochlorine compounds in the SML with respect to the underlying water column ranged from 0.2 to 7.4. This may be explained for both the dissolved + colloidal and particulate phases by the enrichment in the SML of organic carbon (OC) as discerned from particle–water and colloid–water partitioning.     

土壤中25种有机氯农药和多氯联苯的气相色谱分析方法研究

研究了土壤中17种有机氯农药和8种多氯联苯组分的气相色谱分析方法。采用加速溶剂萃取技术提取,优化了萃取条件。提取液用固相萃取技术进行净化,采用20 mL含3%(体积分数)甲苯的正己烷-乙酸乙酯(体积比8∶2)进行淋洗,得到很好的净化效果。方法检出限在0.06~0.27μg/kg,线性范围在1.38~55.2 ng/mL,目标化合物的平均添加回收率在65%~97%,相对标准偏差(RSD,n=6)小于17.11%。方法快速、灵敏、准确,适合批量样品的分析。     

气相色谱-串联质谱技术分析地质调查植物样品中持久性有机污染物的优势

对于复杂基质的样品,采用气相色谱法、气相色谱-质谱法( GC - MS)不能满足当前痕量水平分析的要求,串联质谱已发展成一种有机分析测试的成熟技术可应用于地质调查样品分析.本文建立了气相色谱-串联质谱技术( GC - MS - MS)分析植物样品中有机氯农药及多氯联苯的方法,通过对植物样品(圆白菜、菠菜、胡萝卜、橘子)分析,系统比较了GC- MS-MS与气相色谱-电子捕获检测器(GC-ECD)和气相色谱-选择离子-质谱( GC - SIS - MS)三种分析技术的检出限、定性定量分析结果,确认了分析方法的适用性.GC- MS-MS方法的检出限为0.03～0.29 ng/g,大部分化合物均低于GC -ECD的检出限,是GC - SIS -MS检出限的0.4倍.GC- MS-MS分析表明,圆白菜不含反式-氯丹,排除了GC-ECD的假阳性检出;检测胡萝卜等基质复杂、净化困难的样品,GC- MS-MS也表现出良好的定性定量能力;检出低含量水平样品菠菜含有0.26 ng/g六氯苯,而气相色谱未检出,表明GC- MS-MS显著提高了分析灵敏度,能够对样品中低含量的化合物进行准确定量.在三种分析技术中,GC- MS-MS在样品的准确定性、复杂基质样品分析灵敏度、低含量水平准确定量等方面都具有独特的优势,同时能够应用于复杂样品检测结果的确证.     

莱州湾海域水体中有机氯农药和多氯联苯的浓度水平和分布特征

以固相萃取/气相色谱法测定了莱州湾海域水体中22种有机氯农药和多氯联苯类化合物的浓度水平和分布特征。结果表明,莱州湾海域表层水体中有机氯农药浓度范围为N.D.~32.7ng/L,底层水中的浓度范围为N.D.~11.7ng/L。在该海域水体中共检出有机氯农药3种,β-666是水体中主要的有机氯农药污染物。多氯联苯类在底层水样中检出2种,总浓度范围在4.5~27.7ng/L之间。该海域有机氯农药和多氯联苯的分布特征是近岸高,离岸低,由近岸向湾外延伸方向依次递减。并对莱州湾表层水中总有机氯农药与海水盐度、氯度、溶解氧和pH间的关系作了初步探讨,得出总有机氯农药与盐度、氯度间有一定的相关关系,相关系数均为0.59。方法测定5种有机氯农药化合物的空白加标回收率为97.3%~126.0%,相对标准偏差为2.8%~8.6%;测定5种多氯联苯类化合物的空白加标回收率为88.6%~151.8%,相对标准偏差为6.7%~10.4%。     

Persistent threats need persistent counteraction: Responding to PCB pollution in marine mammals

Polychlorinated biphenyls (PCBs) are a type of persistent organic pollutant (POP) that continues to pose a significant environmental threat to humans and wildlife. Recent scientific evidence shows that very high PCB concentrations are still major causes of contemporary declines in European cetacean populations, and potentially other marine apex predators globally. Currently, controls on PCBs are insufficient, on their own, to fully protect human health or to conserve wildlife. Although the Stockholm Convention provides a global framework to address PCBs, there appears to be a systemic shortfall of many parties of the Convention to provide sufficient prioritisation and resources for effective implementation. A 2015 United Nations Environment Programme assessment estimates that the vast majority of PCB-contaminated equipment and materials, around 14 million tonnes, still requires elimination. At present rates of PCB elimination or mitigation, many countries, including some European countries, will not achieve the 2025 and 2028 targets of the Stockholm Convention. It is imperative that the Conference of the Parties for the Stockholm Convention conclude article 17 negotiations on a compliance mechanism for the Convention as soon as possible. To help mobilise global efforts towards eliminating the threat from PCBs, an enforceable, effective and robust compliance mechanism should be established, along with capacity building support for developing countries. In Europe, renewed action is needed to reduce PCB contamination, in order to prevent some killer whale (Orcinus orca) and other dolphin populations from continuing to slowly decline, potentially towards extinction.     

Concentrations of PCBs in coastal mangrove sediments of Hong Kong

The concentrations of polychlorinated biphenyls (PCBs) in surface sediments of ten mangrove sites in Hong Kong were determined by Congener-specific and Arcolor methods. Spatial variations were found between mangrove sites and within the same site, indicating that the sediment samples were heterogeneous and total PCBs concentrations in mangrove sediments should be normalised to compensate for natural variability and for identifying serious anthropogenic contamination. In addition to total organic carbon, Al, Fe and Mn were possible normalisers. Based on PCB/normaliser ratio and 95% prediction limits of scatter plots between total PCB and normaliser, all mangrove sites were not seriously contaminated by human activities. The estimated total PCBs concentrations (quantified by Congener-specific method) for most sediment ranged from 0.5 to 5.8 ng g(-1) (dry weight, n = 92). However, very high concentrations of PCB were found in sub-samples from Yi O, Tolo Pond and Lai Chi Wo, suggesting that these samples represented the PCB contaminated "hot spots".