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2L - Immunotoxicity - genotoxicity - ED (WEP/117) Validation and use of new Test for the Assessment of Environmental Genotoxic Risk. Geffard, Olivier 1, Budzinski, Hélène1, Lapeyre, Jean-Bastien1, 1 LPTC - Université de Bordeaux1, Talence, France ABSTRACT- Marine and estuarine areas constitute a sink for pollutants from natural and anthropogenic origin and may pose short term (metals, pesticides) or long term (PAHs, PCB) risks for living organisms. Toxicity assessment of aquatic environments is now a major necessity for many countries in the world, imposing to develop sensitive and early-warning tools. Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous compounds. Due to their carcinogenic and mutagenic properties, these compounds have been intensively studied in the various compartments of the environment. PAHs are characterised by a high hydrophobicity and consequently, they are readily accumulated. After uptake by the organism, PAHs induce detoxification processes (biotransformation) in which polar and more reactive compounds can be produced (diols and diol-epoxides). This results in covalent interactions with nucleic acids and proteins. Consequently DNA adducts, strand breaks, chromosomal aberrations and sister chromatid exchanges have been proposed as genotoxicity biomarkers for monitoring the quality of marine environment. More recently, a new genotoxicity test, Damaged DNA Detection test (3D test), has been developed. The 3D test allows the detection of all DNA lesions by quantifying repair activities, using specific protein complexes. This test has been currently used in cosmetology and pharmacology research, but not in environmental toxicology. The aim of this investigation was to use the 3D test and develop a new environmental genotoxic tool based on it. For this, it was intended to use the 3D test with bivalve adults and larvae, Mytilus galloprovincialis. In the first part, the 3D test has been validated, 1:by assessing the impact of the sample storage and of DNA extraction methods on the 3 D test results, 2:by obtaining dose-response curve with a known genotoxic compound. In second part, the 3 D test was applied on mussel adults and larvae, previously exposed to contaminated media and aquatic areas submitted to potential genotoxic compounds. The implications of these results for the use of 3D test in environmental monitoring are discussed. Key words: Mytilus galloprovincialis, 3D test, larvae, Marine environment |
