黄海近岸底栖贝类体内典型有机污染物分布

根据第二次全国海洋污染基线凋查数据,确定黄海近岸底栖贝类体内典型有机污染物的含量、分布及其潜在的生态风险.结果表明,在35%以上的站点,物种体内石油烃含量超过国家海洋生物质量第一类标准(15 000 ng/g),大连湾附近海域贝类体内含量甚至高出第二类标准(50 000 ng/g).在威海、大连湾和胶州湾出现多环芳烃和酞酸酯少数相对高值站点(300 ng/g左右),而其它大多数站点贝类体内多环芳烃和酞酸酯的含量都较低.中、高环组分占优指示近岸海区的多环芳烃主要来源于热解过程;二丁基酞酸酯和2-乙基己基酞酸酯是酞酸酯的主要组分.在所有站点,底栖贝类体内PCBs的含量普遍很低(<10 ng/g).贝类体内DDTs含量超过第一类标准(10 ng/g)的站点大部分集中在南黄海沿岸,海州湾内一站点已超出第二类标准(100 ng/g),而组分以代谢产物DDD和DDE为主.在所有站点的贝类体内都有p,p'-DDT检出,尤其在北黄海的大连湾和蓬莱附近海区(比例高于50%),指示周边地区存在潜在的DDT输入源.据此,大连湾、威海、胶州湾沿岸贝类体内石油烃和多环芳烃含量较高,胶州湾、海州湾附近海域贝类体内DDTs含量较高,这些属于较高生态风险区,而大连湾、蓬莱近岸可能的DDT新输入对底栖环境构成一定威胁.

Distribution of Typical Organic Pollutants in Benthic Mussels from the Inshore Areas of Yellow Sea

Based on the second national baseline survey on marine pollution, the concentration, distribution and potential ecological risk of typical organic pollutants in the benthic mussels from the inshore areas of Yellow Sea were determined. The results indicated that, at over 35% of the total sampling sites, the tissue concentrations of petroleum hydrocarbons were higher than the Category I (15 000 ng/g) of the national marine biological quality standards, and at the sites near Dalian Bay, the tissue concentrations even exceeded the Category II (50 000 ng/g). At minor sites located in Dalian Bay, Weihai and Jiaozhou Bay, relatively high concentrations of polycyclic aromatic hydrocarbons (PAHs) and phthalate esters (PAEs) occurred, while the concentrations of PAHs and PAEs in mussels at most other sites were low. The dominant median and high rings components indicated pyrolytic procedures as the main source of local PAHs, and DBP and DEHP were the major constitution of phthalate esters. At all the sites, the tissue concentrations of PCBs were generally low (< 10 ng/g). The sites with DDTs concentrations over the Category I of the national quality standards were mainly situated in the southern coasts of Yellow Sea, and the predominant fractions were the metabolites of DDT, i.e., DDD and DDE. p, p'-DDT was detected in mussel species at all the monitoring sites, especially at the sites close to Dalian Bay and Penglai (fraction > 50%), which indicated potential inputs from the neighboring areas. Accordingly, petroleum hydrocarbons and PAHs in mussels at the coastal areas of Dalian Bay, Weihai and Jiaozhou Bay were high, the tissue DDTs levels at the sitesnear Jiaozhou Bay and Haizhou Bay were high, these sea areas had therefore higher ecological risk, and new inputs of DDT in the inshore areas of Dalian Bay and Penglai may threat on the benthic surroundings.