闽北地区淡水贝类有害金属铅镉含量调查与食用建议

The survey on the content of lead and cadmium in freshwater clam in the region of Mingbei and serving suggestions

目的：了解闽北地区建溪、富屯溪沿岸市场所售河螺、河蚬中有害金属元素铅（Pb）镉（Cd）含量,调查其生态环境中受污染状况。方法：对辖区内两条主干河流两岸的18个农贸市场所销售铜锈环棱螺、黄螺、河蚬中的Pb、Cd元素用石墨炉原子吸收光谱法进行定量分析。结果：23份样品中的Pb元素平均含量为1.19 mg/kg,最高值为2.58 mg/kg,一日清水育养后均值为0.62 mg/kg,二日清水育养后均值为0.36 mg/kg。Cd元素平均含量为0.75 mg/kg,最高值为8.04 mg/kg,一日清水育养后均值为0.37 mg/kg,二日清水育养后均值为0.21 mg/kg。结论：对照GB 18406.4-2001农产品安全质量无公害水产品安全要求[1]（Pb≤0.5 mg/kg,Cd≤0.1 mg/kg）,检测的淡水贝类生物体内的Pb平均含量超标2.38倍,Cd平均含量超标7.5倍,提示建溪、富屯溪流域水体已受到有害金属Pb、Cd的严重污染。将贝类经清水育养后,体内的Pb、Cd含量明显下降,建议在食用前将贝类在清水中育养、净化2－3天后再加工食用。

Objective：Learn the content of Lead（Pb） and Cadmium（Cd） in river snail and corbicula fluminea sold in the markets along the river of Jian Xi and Futun Xi in Mingbei region. Methods： Investigate Bellamya aeruginosa,Yellow snail,Corbicula fluminea in 18 markets near the main rivers in areas,analyse the content of Pb and Cd by graphite furnace atomic absorption spectrometry quantitatively.Results： The average contents of Pb in total 23 sample is 1.19 mg/kg up to as much as 2.58 mg/kg.Then after nurturing one day,The average is 0.62 mg/kg,and two days later,they reduce to is 0.36 mg/kg.The figure about Cd is 0.75 mg/kg in average with the maxmum 8.04 mg/kg.the average contents decline to 0.37 mg/kg after one day of feeding and down to 0.21 mg/kg by two days＇ feeding.Conclusion： According to GB 18406.4-2001,the safety requirements of agriculture product quality and Non-Pollution aquatic product[1]（Pb〈0.5 mg/kg,Cd〈0.1 mg/kg）.The average contents of Pb in freshwater clams is 2.38 times as much as the standard,that of Cd is 7.5 times as much as the standard.It means that the water in rivers of Jian and Futun have been polluted by Cd and Pb.Such amounts reduce significantly after feeding mussels in clean water.Thus,it is suggested to feed mussels over two days before the further progress.