title: Toxicity of short-term copper exposure to early life stages of red sea bream, Pagrus major.
abstract: Acute (0, 0.1, 0.2, 0.4, 0.8, 1.6 mg Cu/L) and chronic (0, 0.02, 0.04, 0.06, 0.08, 0.10, 0.12 mg Cu/L) toxicity tests of Cu with embryonic and larval red sea bream, Pagrus major, were carried out to investigate their biological responses to Cu exposure in static water at 18 +/- 1 degrees C (dissolved organic carbon, 1.8 +/- 0.65 mg C/L; hardness, 6,183 +/- 360 mg CaCO3/L; salinity, 33 +/- 1 per thousand). The 24- and 48-h LC50 (median lethal concentration) values of Cu for embryos were 0.23 and 0.15 mg/L, whereas the 48-, 72-, and 96-h LC50 values for larvae were 0.52, 0.19, and 0.13 mg/L, respectively, suggesting that embryos were more sensitive to Cu toxicity than larvae. Copper exposures at > or =0.06 mg concentrations caused low hatching success, a delay in the time to hatching of embryos, and reductions in the growth and yolk absorption of the larvae, whereas high mortality and morphological malformations occurred in the embryos and larvae at > or =0.08 mg/L concentrations. Copper concentration did not significantly affect the heart rate of the embryos, but it significantly decreased the heart rate of the newly hatched larvae when the Cu concentration was > or =0.08 mg/L, suggesting that Cu at high concentrations could induce heartbeat disturbances in red sea bream more easily at the larval stage than at the embryonic stage. Hatching success, time to hatching, growth rate, morphological abnormality, yolk absorption, and heart rate were Cu concentration-dependent and could be effective endpoints for evaluating Cu toxicity to the early life stages of red sea bream in nature.
authors.affiliation: Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Cao
authors.forename: Wei
authors.initials: W
authors.lastname: Huang
authors.forename: Jinhu
authors.initials: J
authors.lastname: Liu
authors.forename: Zhenjiang
authors.initials: Z
authors.lastname: Ye
authors.forename: Shuozeng
authors.initials: S
authors.lastname: Dou
mesh_terms: D000014:Abnormalities, Drug-Induced / Q000473:pathology / Q000662:veterinary; D000818:Animals; D003300:Copper / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004625:Embryo, Nonmammalian / Q000187:drug effects*; D047108:Embryonic Development / Q000187:drug effects; D007814:Larva / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D021541:Sea Bream / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D012623:Seawater / Q000737:chemistry; D023382:Toxicity Tests, Acute; D036401:Toxicity Tests, Chronic; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D003300:Copper