title: The effects of mariculture on heavy metal distribution in sediments and cultured fish around the Pearl River Delta region, south China.
abstract: Thirty-six sediment samples were collected from six mariculture sites and corresponding reference sites (approximately 200-300 m away from each mariculture site) to study the effects of mariculture on heavy metal: copper (Cu), zinc (Zn), chromium (Cr) and lead (Pb) distribution in sediments and cultured fish around the Pearl River Delta region, south China. The mean concentrations of Cu, Zn, Cr and Pb in all mariculture sediment samples were 109, 273, 99 and 33 mg/kg, compared with 63, 209, 56 and 23 mg/kg for reference sediment samples, respectively. The Pollution Load Index of sediment for each site was over 1, implying substantial heavy metal pollution. The results of principal component analysis and hierarchical clustering analysis indicate that marine aquaculture activities have enriched the surface sediments underneath mariculture rafts with Cu, Zn and Pb, possibly due to the accumulation of unconsumed fish feeds, fish excreta and antifouling paints (except Cr). Two kinds of fish feeds, feed pellets and trash fish commonly used in Hong Kong were analyzed. The concentrations of Zn and Cu contained in feed pellets were significantly higher (p < 0.05) than in trash fish due to addition of these elements as growth promoters during pellet production. However, the Pb content in trash fish (due to contamination) was significantly higher (p < 0.05) than in feed pellets. Three cultured fish species, namely red snapper (Lutjanus campechanus), orange-spotted grouper (Epinephelus coioides) and snubnose pompano (Trachinotus blochii), were collected from each mariculture site for metal analysis. Lead concentrations in 21 fish samples exceeded the Chinese safety guideline (0.5 mg/kg, GB18406.4-2001), indicating that Pb contamination in cultured fish would be a public health concern.
authors.affiliation: School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Liang
authors.affiliation: School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province, China.
authors.forename: Sheng-Chun
authors.initials: SC
authors.lastname: Wu
authors.affiliation: School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province, China.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province, China.
authors.forename: Yucheng
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen, China. Electronic address: syu@iue.ac.cn.
authors.forename: Shen
authors.initials: S
authors.lastname: Yu
authors.affiliation: School of Environmental and Resource Sciences, Zhejiang Agricultural and Forest University, Lin'an, Zhejiang Province, China; School of Environment, Jinan University, Guangzhou, China; Consortium on Health, Environment, Education and Research (CHEER), Hong Kong Institute of Education, Hong Kong, China. Electronic address: mhwong@hkbu.edu.hk.
authors.forename: Ming-Hung
authors.initials: MH
authors.lastname: Wong
mesh_terms: D000818:Animals; D017756:Aquaculture; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000032:analysis / Q000737:chemistry*; D006723:Hong Kong; D019216:Metals, Heavy / Q000032:analysis* / Q000378:metabolism; D010473:Perciformes / Q000254:growth & development / Q000378:metabolism*; D045483:Rivers; D017747:Seafood / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000378:metabolism
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
keywords: Aquaculture; Fish; Heavy metals; Pearl River Delta; Sediment