福建三都湾渔业环境和养殖生物体总汞含量及人体暴露健康风险评价

Total mercury in the marine culture products and relative environmental samples from Sandu Bay of Fujian Province and its health risk assessment

由于汞的生物甲基化和在食物链中的积累、放大作用,水产类膳食汞的摄入被认为是人体甲基汞负荷的主要来源。三都湾位于福建省东北部沿海,各类水产生物养殖面积1.5万hm2,年产量22.5万t。为评估甲基汞的健康风险,2004年在该湾采集海水样品9个、表层沉积物样品11个、养殖鱼类样品31个以及养殖贝类样品4个,用原子荧光光度法进行海水、沉积物和养殖生物总汞含量测定,对三都湾渔业环境汞污染现状和水产品质量安全进行评价。三都湾海水总汞含量范围在0.015～0.046μg/L,计(0.027±0.009)μg/L;沉积物总汞含量范围在0.055～0.113mg/kg,计(0.074±0.013)mg/kg,养殖贝类总汞含量范围在0.004～0.011mg/kg,计(0.008±0.005)mg/kg,与福建沿岸近20年来的其他相关调查结果相接近。养殖鱼类总汞含量范围在0.012～0.084mg/kg,计(0.032±0.006)mg/kg。通过调查数据的对比分析,三都湾鱼、贝类体总汞平均含量近30年来一直波动于鱼类汞含量的下限(0.05mg/kg)区间,与海水和沉积物汞的含量水平和变化趋势基本相对应;与美国、日本最近公布的鱼、贝类汞含量进行比较,三都湾牡蛎汞平均含量与日本的太平洋牡蛎和美国的牡蛎较接近,但三都湾牡蛎汞含量的最大值(0.011mg/kg)比日本、美国的牡蛎汞含量的最大值(0.250mg/kg和0.130mg/kg)低得多;三都湾大黄鱼、汞平均含量(0.026mg/kg和0.036mg/kg)和最大含量(0.084mg/kg和0.053mg/kg)均比美国的大西洋石首鱼(0.072mg/kg和0.148mg/kg)低;三都湾的鲈鱼汞平均含量(0.056mg/kg)低于日本的鲈鱼(0.100mg/kg)和美国的红鲈(0.128mg/kg)。后二者汞含量最大值(0.510mg/kg和0.625mg/kg)分别是三都湾养殖鲈鱼(0.075mg/kg)的6至8倍。三都湾海水、沉积物、贝类总汞含量符合国家环境质量标准,养殖鱼、贝类符合国家、WHO及欧盟的水产品汞限量要求。以100g/(人d)的水产类摄食量估算,食用鱼、贝类汞摄入量分别占JECFA推荐的汞临时性周可承受摄入量PTWI值的8.4%和2.9%;用总汞数据估算甲基汞摄入量分别占PTWI值的26.4%和9.0%。采用美国EPA设定的甲基汞RfD值估算,食用鱼、贝类甲基汞摄入量分别占60.3%和20.6%。三都湾沿海城乡居民水产品消费引起的汞暴露健康风险小。

Due to the facts of bio-methylation and bio-magnification/accumulation of mercury, mercury in cultured creatures has been considered to be the main source of methylmercury in human being. Sandu Bay, located at the northeastern coast of Fujian Province, has an area of 15 thousand hm2 for various marine cultures and provides 225 000 t products each year. To assess the health risk of methylmercury, 9 seawater samples, 11 surface sediment samples, 31 cultured fish samples and 4 cultured shellfish samples were collected from Sandu Bay in 2004. The analysis of total mercury in the samples was carried out with atomic fluorescence spectrophotometric method, and the mercury pollution level at Sandu Bay and the health risk were assessed. Total mercury contents in seawater, sediment, cultured shellfish and fish samples ranged from 0.015μg/L to 0.046 μg/L, 0.055 mg/kg to 0.113 mg/kg, 0.004 mg/kg to 0.011 mg/kg, and 0.012 mg/kg to 0.084 mg/kg, respectively; and the values were （0.027±0.009） μg/L, （0.074±0.013） mg/kg, （0.008±0.005） mg/kg and （0.032±0.006） mg/kg, respectively. These results were comparable with those of other research on Fujian coastal areas in 20 years. The averaged total mercury concentration in cultured fish and shellfish has been about 0.05 mg/kg for 30 years, corresponding to that of in seawater and sediments. Compared with the data of total mercury concentration in fish and shellfish released recently by USA and Japan, the concentration in oyster of Sandu Bay was closed to that in Pacific oyster of Japan and in oyster of USA. However, the highest concentration （0.01 lmg/kg） found in oyster of Sandu Bay was much lower than that found in Japan （0.250 mg/kg） and USA （0.130 mg/kg）. The averaged and the highest concentrations in Large Yellow Croaker （Pseudosciaena crocea） （0.026 mg/kg and 0.084 mg/kg, respectively） and Slate Cod Croaker （Nibea miichthioides） （0.036 mg/kg and 0.053 mg/kg, respectively） of Sandu Bay, were much lower than those found in Croaker Atlantic （0.072 mg/kg and 0.148 mg/kg, respectively） of USA. The averaged concentration in Weever （Lateolabrasjaponicus） （0.056 mg/kg） of Sandu Bay was lower than that in Japanese Sea Bass Perch （0.100 mg/kg） and US Sheepshead （0.128 mg/kg）. The highest concentrations of Japanese Sea Bass Perch and US Sheepshead, 0.510 mg/kg and 0.625 mg/kg, respectively, were 6 to 8 times higher than that （0.075 mg/kg） in Sandu Bay. Total mercury in the seawater, sediment and shellfish samples of Samdu Bay met the national environmental quality criteria. Mercury in the cultured fish and shellfish was below the limits of aquatic products regulated by China, WHO and EU. Taking 100 g/（person＇day） as the possible up- take amount of total mercury from fish and shellfish of Sandu Bay for estimation, it is only 8.4 % and 2.9 % of what suggested by JECFA, respectively. The possible up-take amount of methylmercury from fish and shellfish of Sandu Bay would be only 26.4% and 9.0% of PTWI, and 60.3% and 20.6% of RfD value by US EPA, respectively. The health risk arising from the exposure to mercury due to the consumption of aquatic products of Sandu Bay was small. [ Journal of Fishery Sciences of China, 2008, 15 （6） ： 961-969]