Heavy Metal Concentrations In Aquatic Products And Health Risk Of Human Exposure In Typical Aquatic Cities In China

Objective:This study is designed to investigate the pollution status of heavy metals in main aquatic products from four typical aquatic regions in China(Qingdao,Xiamen,Zhoushan and Wuhan),and to provide reference for dietary guidance of aquatic products for residents in coastal areas.The heavy metal concentrations in human hair,health risks of heavy metal exposure,and the factors were evaluated.Methods:A total of 519 aquatic products samples and 32 rice samples from Qingdao,Xiamen,Zhoushan,and Wuhan City were collected.A total of 508 local residents' hair samples were randomly collected.At the same time,basic information and dietary information of local residents were collected through questionnaire.The concentrations of Cd,As,Pb,Cr,Cu,and Zn in aquatic products,rice and hair samples were determined by Inductively Coupled Plasma Mass Spectrometry(Nex ION 300 X,Perkin Elmer).Results:1.The median concentrations of Cd,As,Pb,Cr,Cu and Zn in 519 aquatic products samples of the four regions were 0.004 mg/kg,1.73 mg/kg,0.015 mg/kg,0.124 mg/kg,0.382 mg/kg and 7.40 mg/kg,respectively.The averages of Cr concentrations in Spanish mackerel in Qingdao and mullet in Wuhan were 0.743 ±0.981 mg/kg and 0.675 ± 0.751mg/kg,respectively,and 10%(1/10)and 13%(1/8)of the Spanish mackerel and mullet samples exceeded national limit(2.0 mg/kg for fish),respectively.The average of Cd concentrations of scallop samples in Qingdao was2.45 ± 2.37 mg/kg,and 50% of scallop samples(6/12)exceeded national limit(2.0mg/kg for bivalve).The average of Cd concentrations in the mantis shrimp from Qingdao and Zhoushan was 1.43 ± 0.227 mg/kg,which all exceeded national limit(0.5 mg/kg for crustaceans).2.The concentrations of heavy metals in all rice samples from the four regions did not exceed national limit.3.When the estimated weekly intake of scallop and shrimp in Qingdao reaches 26.2 g/d and 56.1 g/d respectively,and when the daily intake of shrimp in Zhoushan reaches 37.1 g/d,the weekly tolerable intakes of Cd exceed the limit of 7 ?g/kg·bw set by Joint FAO/WHO Expert Committee on Food Additives(JECFA),which showed the risks of Cd exposure;When the intake of mullet in Wuhan and Spanish mackerel in Qingdao reaches 87.6g/d and 208 g/d,respectively,the weekly tolerable intake of Cr exceed the limit of 6.7?g/kg·bw set by JECFA,and residents may face the risk of Cr exposure.4.The concentrations of heavy metals in different kinds of aquatic products showed the pattern: fish < crustacean < mollusk.Among them,the concentrations of six heavy metals in mollusks were significantly higher than those in fish(p < 0.05),the concentrations of Cd,Pb,Cu and Zn in crustaceans were significantly higher than those in fish(p < 0.05),and the concentrations of Cd and Pb in mollusks were significantly higher than those in crustaceans(p < 0.05).5.The median concentrations of Cd,As,Pb,Cr,Cu and Zn in the hair samples were 0.227 mg/kg,0.0745 mg/kg,0.858 mg/kg,0.621 mg/kg,8.59 mg/kg and 157 mg/kg,respectively.Among them,30%(35/116)of Cr and 22%(26/116)of Zn in the the hair samples from Wuhan exceeded the national recommended value,and 28%(37/130)of Zn in the hair samples from Qingdao exceeded the recommended value.6.The percentages of hair Cu and Zn concentrations below the lower limit in Wuhan,Qingdao,Xiamen and Zhoushan Cities were 36%(181/508)and 10%(49/508),respectively.The percentage of hair Cr concentrations below the lower limit in Wuhan,Qingdao and Xiamen Cities was 18%(70/390).7.Significant differences of the concentrations of Cu and Zn in the hair samples of residents in the four regions were found between different groups of fish eating frequency,which showed an increasing trend with the increasing of fish eating frequency.Multivariate logistic regression analysis showed that residents with high fish eating frequency had higher hair Cu and Zn concentrations,which indicated that aquatic food was one of the important sources of Cu and Zn exposure for the residents.8.The hair Cd,Pb and Zn concentrations varied significantly with age.The hair Cd,Cu and Zn concentrations in females were significantly higher than those of males,while hair As concentrations in males were significantly higher than those of females.Conclusions:The Cr concentrations in Spanish mackerel from Qingdao City and mullet from Wuhan City,Cd concentrations in scallop and mantis shrimps from Qingdao City and Cd concentrations in mantis shrimps from Zhoushan City partially exceeded national limit,therefore local residents should avoid and reduce consumption of these species.The heavy metals concentrations in different kinds of aquatic products showed the trend: mollusk > crustaceans > fish.Factors influencing hair heavy metal concentrations included age,gender and consumption frequency of aquatic products.The exceeding rates of hair Cr and Zn concentrations in Wuhan were 30% and 22%,respectively,and the exceeding rates of hair Zn concentrations in Qingdao were 28%,indicating that local residents had a certain risk of Cr and Zn exposure.In addition,The percentages of hair Cr,Cu and Zn concentrations below the lower limit were18%,36% and 10% respectively,and these residents should increase the dietary intake of oysters and other foods with high concentrations of Cu and Zn.This study can provide important guidance for the dietary intake of aquatic products and the risk control of heavy metal exposure in typical aquatic cities in China.