粤东海产经济贝类重金属含量与暴露风险评价

Analysis of heavy metal concentrations in marine economic shellfish from eastern Guangdong Province and its health risk

为了解粤东地区海水经济贝类重金属的污染现状及摄入健康风险,本研究采用电感耦合等离子体发射光谱法(ICP-AES)分别测定了10种海产经济贝类肌肉和内脏团中6种重金属(Zn、Cd、Pb、Cr、Cu及Mn)的质量分数,并采用单因子污染指数(Pi)、目标危险系数(THQ)及总目标危险系数(TTHQ)分别评价其污染程度和食用健康风险。结果表明,该10种贝类肌肉中重金属质量分数的平均值由高至低为Zn>Mn>Cu>Cr>Cd>Pb,内脏团中为Zn>Mn>Cu>Pb>Cr>Cd。除Cr外,贝类内脏团中其他5种金属质量分数的平均值均高于其相应的肌肉组织。Pi结果表明,除Cu外,贝类肌肉和内脏团均受Zn、Cd、Pb、Cr不同程度的污染,其中Cd的Pi最高,其次为Zn、Pb,而Cr指数相对较低;且大多数贝类内脏团中Cd、Zn及Pb的Pi值指示为重污染水平(即超标)。THQ评价结果显示,除了栉江瑶内脏团中的Cd外,该10种贝类中5种重金属暴露对儿童或成人没有明显的健康风险;但TTHQ结果表明,约有50%贝类的内脏团重金属TTHQ值大于1,表明暴露人群若长期食用这些贝类的内脏团将对健康产生负面影响。总之,粤东地区10种海水经济贝类分别受到Cd、Zn、Pb和Cr不同程度的污染,表明该地区海洋生态环境或贝类生产已存在重金属污染的安全隐患,建议加强该地区贝类产品重金属残留的质量监控及重金属污染的防控。

In order to evaluate the status of heavy metal pollution on marine economic shellfish in eastern Guangdong and the intake of health risk, the contents of lead(Pb), cadmium(Cd), chromium(Cr), copper(Cu), zinc(Zn)and manganese(Mn)in muscle and visceral mass from 10 species of shellfish were determined by using method of inductively coupled plasma atomic emission spectrometry(ICPAES). The single factor pollution index(Pi), target hazard quotient(THQ)and the total target hazard quotient(TTHQ)were used to evaluate the pollution status of heavy metals and dietary health risk. Results showed that the levels of metals in muscles of the shellfish were found in order of Zn>Mn>Cu>Cr>Cd>Pb, while which in visceral mass were in order of Zn>Mn>Cu>Pb>Cr>Cd. Except Cr, the heavy metals concentrations in visceral mass samples were significantly higher than those in the corresponding muscles. Based on the Pi indexes, the shellfish were polluted to one degree or another by Cd, Pb, Cr and Zn, except the Pi indexes of Cu. The shellfish Pi index from high to low was in order of Cd> Zn>Pb>Cr>Cu, While the Pi index of Cd, Zn and Pb in most shellfish viscera were in heavy pollution level. The results of THQ showed that the indexes exposure to individual metal(Cd, Zn, Pb, Cr, Cu, respectively)were at none risk level for children and adults except the index of Cd in visceral mass of Pinna pectinata. However, TTHQ results showed that the TTHQ value in about half of the shellfish species were more than 1, which indicated that long-term consumption of the visceral mass of these species would have a negative impact on human health. In summary, the shellfishes were polluted by Zn, Cd, Pb and Cr to some extent, which indicated that hidden danger of heavy metals pollution was present in ecological environment and fishery production in the area, and the monitoring of heavy metal residue in shellfish and heavy metals pollution need to be strengthened.