| Objective:The objective of this study is to determine total mercury?THg?and methylmercury?MeHg?concentration in different species of aquatic products and cereals?rice and flour?from Wuhan,Qingdao and Xiamen;explore the characteristics of mercury concentration in different species of aquatic products,provide data reference for public people to consumption fish,identify the major mercury exposure pathways in each region and assess potential exposure risk of mercury in the three local residents.Methods:Considerate the different types of aquatic products,the diet structure and consumption levels of residents in the study areas,a total of 432aquatic products samples and 434 human hair samples were collected from Wuhan,Qingdao,and Xiamen?the local rice and flour samples were collected?.At the same time,a questionnaire survey was conducted to obtain the local demographic data.The THg in the aquatic products samples was measured by DMA-80 instrument,the THg in the hair samples was determined by LUMEX instrument;the THg in rice and flour was measured by cold vapor atomic fluorescence spectroscopy?CVAFS?;the MeHg was measured by GC-CVAFS method after digestion by alkaline solution.Results:1.The mercury content in different types of aquatic products in Wuhan,Qingdao and Xiamen were obviously different.The M(P25,P75)of THg in fish,shrimp and mollusks were 17.5?10.8,38.1?ng·g-1,16.0?9.55,32.0?ng·g-1,8.80?6.64,12.0?ng·g-1;the M(P25,P75)of MeHg were 10.5?6.45,30.9?ng·g-1,9.67?5.72,31.1?ng·g-11 and 4.79?2.62,6.72?ng·g-1;The average ratio of MeHg/THg for the tested species were 57.3%,64.3%and 49.4%.The mercury of the mollusks is significantly lower than fish and shrimp?P<0.05?.The THg concentration in rice and flour were2.73±0.47 ng·g-1,1.60±0.31 ng·g-1,the MeHg were 1.31±0.15 ng·g-1,0.62±0.14ng·g-1;2.The mercury contentration are various in different types of aquatic products in the three regions:the M(P25,P75)of fish THg concentration in Wuhan,Qingdao,and Xiamen were 12.8?6.71,23.1?ng·g-1,22.4?14.8,36.9?ng·g-11 and 40.1?13.4,54.4?ng·g-1,respectively.The mercury concentration of fish in Wuhan were lower than Qingdao and Xiamen?P<0.05?.The M(P25,P75)of THg concentration of Crayfish in Wuhan were 44.8?36.5,54.3?ng·g-11 higher than shrimps in Qingdao and Xiamen 15.2?12.4,31.7?ng·g-1,12.0?4.17,23.6?ng·g-1?P<0.05?.The M(P25,P75)THg concentration of mollusks in Xiamen were 9.60?7.41,21.5?ng·g-11 higher than8.17?5.24,11.1?ng·g-11 in Qingdao?P<0.05?.3.The M(P25,P75)of estimated daily intake?EDI?of THg and MeHg in the three areas were 33.5?24.8,49.0?ng·d-1·kg-1,20.8?14.9,32.0?ng·d-1·kg-1 were lower than the reference value of USEPA and JECFA.The EDI of THg and MeHg intake of residents in Xiamen were higher than Wuhan and Qingdao?P<0.05?.The residents in Wuhan were mainly intake MeHg by eating rice?52.9%?,followed is fish?32.6%?;residents in Qingdao mainly intake by fish?72%?,followed is flour?16.4%?;Xiamen is mainly by fish?48.4%?slightly higher than rice?39.1%?.4.The M(P25,P75)of hair THg concentration in Wuhan,Qingdao,and Xiamen were 0.392?0.253,0.611??g·g-1,0.305?0.204,0.478??g·g-1and 0.814?0.445,1.350??g·g-1,respectively.The average ratio of MeHg/THg were54.3%,52.4%and 63.9%,respectively.There were 10?7.2%?,8?5.9%?and 64?40.3%?of population from Wuhan,Qingdao and Xiamen with hair THg concentration exceeding reference value(1?g·g-1)set by USEPA,respectively;and were 0?0%?,1?0.7%?and 21?13.2%?exceeding reference value(2.3?g·g-1)set by JECFA.The THg of hair in Xiamen is higher than Wuhan and Qingdao?P<0.05?.5.With the residents increasing of fish eating frequency,the THg in hair were increased?P<0.05?.Hair THg concentration varied among different age groups,and the highest were obtained in age group of 51-65 years.The ordered Logistic regression analysis is showed:The average odds ratio?OR??95%CI?value of increasing of hair THg in population with eating fish is 17-25 times per month and over 26 times per month was4.22?2.05-8.69?and 11.0?5.05-24.0?,compared with the population eating fish lower than 4 times per month;The average odds ratio?OR??95%CI?value of increasing of hair THg in population age were 36-50 and 51-65 were?2.43-11.55?and 2.78?1.43-5.41?,compared with the population age is lower than 20 years;The average odds ratio?OR??95%CI?value of increasing of hair THg in population with rice consumption was 6.47?4.07-10.29?compared with the population without rice consumption.Conclusions:1.The THg and MeHg concentration of aquatic products,rice and flour in Wuhan,Qingdao and Xiamen are lower than the“Food Contaminant Limit”standard;2.The THg concentration in mollusks is lower than fish and shrimp;the mercury concentration of fish in Wuhan is lower than Qingdao and Xiamen;while the mercury concentration of crayfish in Wuhan is higher than Qingdao and Xiamen.3.The dietary mercury intake characteristics of residents in different regions are various:in Wuhan,the main dietary mercury is through rice intake;in Xiamen,is through rice and fish intake;While,in Qingdao,is through fish intake;4.The population in Xiamen are at higher risks of Hg exposure,compared the population in Wuhan and Qingdao,the frequency of eating fish,the age of residents and whether rice is the main food is an important factor affect the mercury concentration of residents. |
PDF Full Text Request