title: Mercury species of sediment and fish in freshwater fish ponds around the Pearl River Delta, PR China: human health risk assessment.
abstract: This study investigated total mercury (THg) and methylmercury (MeHg) concentrations in five species of freshwater fish and their associated fish pond sediments collected from 18 freshwater fish ponds around the Pearl River Delta (PRD). The concentrations of THg and MeHg in fish pond surface sediments were 33.1-386 ng g(-1) dry wt and 0.18-1.25 ng g(-1) dry wt, respectively. The age of ponds affected the surface sediment MeHg concentration. The vertical distribution of MeHg in sediment cores showed that MeHg concentrations decreased with increasing depth in the top 10 cm. In addition, a significant correlation was observed between %MeHg and DNA from Desulfovibrionacaea or Desulfobulbus (p<0.05) in sediment cores. Concentrations of THg and MeHg in fish muscles ranged from 7.43-76.7 to 5.93-76.1 ng g(-1) wet wt, respectively, with significant linear relationships (r=0.97, p<0.01, n=122) observed between THg and MeHg levels in fish. A significant correlation between THg concentrations in fish (herbivorous: r=0.71, p<0.05, n=7; carnivorous: r=0.77, p<0.05, n=11) and corresponding sediments was also obtained. Risk assessment indicated that the consumption of largemouth bass and mandarin fish would result in higher estimated daily intakes (EDIs) of MeHg than reference dose (RfD) for both adults and children.
authors.affiliation: Croucher Institute for Environmental Sciences, and Department of Biology, Hong Kong Baptist University, Kowloon Tong, Hong Kong, PR China.
authors.forename: Dingding
authors.initials: D
authors.lastname: Shao
authors.forename: Peng
authors.initials: P
authors.lastname: Liang
authors.forename: Yuan
authors.initials: Y
authors.lastname: Kang
authors.forename: Hongsheng
authors.initials: H
authors.lastname: Wang
authors.forename: Zhang
authors.initials: Z
authors.lastname: Cheng
authors.forename: Shengchun
authors.initials: S
authors.lastname: Wu
authors.forename: Jianbo
authors.initials: J
authors.lastname: Shi
authors.forename: Samuel Chun Lap
authors.initials: SC
authors.lastname: Lo
authors.forename: Wenxiong
authors.initials: W
authors.lastname: Wang
authors.forename: Ming H
authors.initials: MH
authors.lastname: Wong
mesh_terms: D000818:Animals; D002681:China; D004781:Environmental Exposure / Q000032:analysis / Q000706:statistics & numerical data; D005399:Fishes / Q000378:metabolism*; D019015:Geologic Sediments / Q000737:chemistry*; D006801:Humans; D008628:Mercury / Q000032:analysis* / Q000378:metabolism; D009132:Muscles / Q000378:metabolism; D018570:Risk Assessment; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D014874:Water Pollutants, Chemical; D008628:Mercury