title: Dietary toxicity of field-contaminated invertebrates to marine fish: effects of metal doses and subcellular metal distribution.
abstract: There is growing awareness of the toxicological effects of metal-contaminated invertebrate diets on the health of fish populations in metal-contaminated habitats, yet the mechanisms underlying metal bioaccumulation and toxicity are complex. In the present study, marine fish Terapon jurbua terepon were fed a commercial diet supplemented with specimens of the polychaete Nereis diversicolor or the clam Scrobicularia plana, collected from four metal-impacted estuaries (Tavy, Restronguet Creek, West Looe, Gannel) in southwest England, as environmentally realistic metal sources. A comparative toxicological evaluation of both invertebrates showed that fish fed S. plana for 21 d exhibited evident mortality compared to those fed N. diversicolor. Furthermore, a spatial effect on mortality was observed. Differences in metal doses rather than subcellular metal distributions between N. diversicolor and S. plana appeared to be the cause of such different mortalities. Partial least squares regression was used to evaluate the statistical relationship between multiple-metal doses and fish mortality, revealing that Pb, Fe, Cd and Zn in field-collected invertebrates co-varied most strongly with the observed mortality. This study provides a step toward exploring the underlying mechanism of dietary toxicity and identifying the potential causality in complex metal mixture exposures in the field.
authors.affiliation: Division of Life Science, The Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Fei
authors.initials: F
authors.lastname: Dang
authors.forename: Philip S
authors.initials: PS
authors.lastname: Rainbow
authors.forename: Wen-Xiong
authors.initials: WX
authors.lastname: Wang
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry*; D004032:Diet; D004305:Dose-Response Relationship, Drug; D004781:Environmental Exposure; D004784:Environmental Monitoring; D020387:Food Chain; D016018:Least-Squares Analysis; D008670:Metals / Q000032:analysis / Q000633:toxicity*; D015999:Multivariate Analysis; D010473:Perciformes / Q000378:metabolism*; D011077:Polychaeta / Q000737:chemistry*; D011897:Random Allocation; D012623:Seawater / Q000737:chemistry; D014018:Tissue Distribution; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D008670:Metals; D014874:Water Pollutants, Chemical