Characterization of toxic effects of sediment-associated organic pollutants using the lambda transgenic medaka.
A novel sediment-contact assay using embryos of the transgenic medaka was developed to fully characterize the toxic effects induced by exposure to a mixture of organic pollutants in sediments. Embryos of the lambda transgenic medaka were exposed for 10 days to a clean reference sediment spiked with either the solvent alone, benzo[a]pyrene (B[a]P), or three concentrations (0.3x, 1x, and 2x) of an organic extract (OE) of sediments from the Seine estuary. The 1 x OE-spiked sediment contained concentrations of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls similar to those in field-collected sediment. Exposure to this sediment, but not to the B[a]P-spiked sediment, significantly increased embryo-larval mortality and prevalence of spinal deformities. Mutant frequency at the cII mutation target gene in the liver of 10-week-old medaka was significantly increased following exposure to either B[a]P or the three doses of OE. The predominant OE-induced liver mutations were G:C to T:A transversions, consistent with PAHs being the major contributors to the mutation induction. Liver and gonadal tumors were observed in 35-week-old medaka exposed to either B[a]P (1/25) or to the 1 x OE (1/24). The benefits of medaka as a fish model for toxicological assessment and the benefits of the cII mutation assay for mutation detection combine to provide comprehensive assessment of a wide range of genotoxic and nongenotoxic effects of aquatic pollutants.
Cachot
Jerome
J
University of Le Havre, LEMA EA-3222, 25 rue Philippe Lebon, B.P. 540, 76058 Le Havre, France. j.cachot@ism.u-bordeaux1.fr
Law
Mac
M
Pottier
Didier
D
Peluhet
Laurent
L
Norris
Michelle
M
Budzinski
Helene
H
Winn
Richard
R
D000818:Animals; D030801:Animals, Genetically Modified; D001564:Benzo(a)pyrene / Q000737:chemistry; D004252:DNA Mutational Analysis; D004784:Environmental Monitoring / Q000379:methods*; D005399:Fishes; D018507:Gene Expression Regulation, Developmental; D019015:Geologic Sediments / Q000032:analysis; D006720:Homozygote; D008099:Liver / Q000378:metabolism; D009154:Mutation; D009930:Organic Chemicals / Q000737:chemistry*; D009990:Oryzias / Q000235:genetics*; D011078:Polychlorinated Biphenyls / Q000737:chemistry; D013997:Time Factors; D014873:Water Pollutants / Q000032:analysis / Q000737:chemistry
D009930:Organic Chemicals; D014873:Water Pollutants; D001564:Benzo(a)pyrene; D011078:Polychlorinated Biphenyls