珠三角河网表层水及水产品中多环芳烃的分布特征

Distribution of Polycyclic Aromatic Hydrocarbons in Surface Water and Aquatic Products from the River Network of the Pearl River Delta

为了解珠江三角洲河网水环境中多环芳烃的富集特征及健康风险,为该地居民的水产品日食用量提出建议,应用固相萃取富集法和气相色谱质谱联用(GC-MS)分析方法对珠三角河网15个表层水体样品及3种主要水产品中15种美国环保局(USEPA)优控多环芳烃的(PAHs)质量分数进行了测定,分析了其在水产品中的富集特征,并进一步采用USEPA推荐的终生致癌风险增量模型(ILCR)估算通过饮水及食用不同水产品造成的健康风险。研究结果表明,珠三角河网水体中15种优控PAHs总质量浓度(∑_(15)PAHs)范围为15.0~19.4 ng?L^(-1);水产品中∑_(15)PAHs的湿重质量分数范围为13.3~32.5 ng?g^(-1)。PAHs单体的辛醇/水分配系数(logK_(ow))与其生物浓缩系数(logBCF)间存在抛物线关系;而与其生物-沉积物累积因子(log BSAF)间存在线性负相关关系。健康风险评估结果表明,珠三角河网居民通过饮水造成的PAHs致癌风险为1.95×10^(-7)~5.34×10^(-7);通过水产品食用造成的致癌风险为4.88×10^(-6)~1.84×10-5,高于USEPA推荐的可接受风险(10^(-6)),存在一定的潜在致癌风险;水产品食用是珠三角河网居民PAHs暴露的主要途径之一。对于成人来说,西江广东鲂(Megalobrama hoffmanni)肌肉中PAHs产生致癌风险允许的最大日食用量(CR_(lim))范围为96.0~228.5 g?d^(-1),鲮(Cirrhina molitorella)的CR_(lim)范围为136.7~359.0 g?d^(-1),花鰶(Clupanodon thrissa)的CR_(lim)范围为111.5~120.0 g?d^(-1)。

In order to investigate the bioconcentration and health risk of PAHs in aquatic environment of Pearl River Delta networkand give suggestions of the daily consumption of aquatic products for residents,spatial distribution of15USEPA priority polycyclicaromatic hydrocarbons(PAHs)in15water samples and3kinds of wild fish from river network of the Pearl River Delta wereexamined by solid phase extraction combined with gas chromatography mass spectrometry(GC/MS)analysis.The incrementallifetime cancer risk model(ILCR)recommended by USEPA were applied to estimate the health risk through the ingestion fromdrinking water and the aquatic products.The concentrations of total PAHs(Σ15PAHs)in the surface water and muscles of fish specieswere in the ranges of15.0~19.4ng.L-1and13.3~32.5ng.g-1wet weight,respectively.The values of Log Kow and log BCF of PAHs inmuscles of fish species existed parabolic relationships,while log Kow and log BSAF of PAHs in fish muscles showed negative linercorrelation.The carcinogenic risks through the drinking ingestion were in the range of1.95×10-7~5.34×10-7,while the health riskthrough fish ingestion were in the range of4.88×10-6~1.84×10-5,which were higher than the baseline value of acceptable risk(10-6).The consumption of aquatic products was one of the main pathways of PAHs exposure for the residents in the Pearl River Delta.Theresults suggested that the maximum acceptable daily intakes for megalobrama hoffmanni,cirrhina molitorella and clupanodonthrissa should be96.0~228.5,136.7~359.0and111.5~120.0g.d-1(by wet mass)respectively,based on the maximum acceptable levelof PAHs cancel control.