Use of biomarkers to assess the effects of in vivo exposure to organochloined and organophosphorous pesticides in the mussels of Agadir Bay (South of Morocco)

摘要

The pesticides constitute one of the major pollutants of the environment;rntheir increased use in relation to the development of agriculture is at thernorigin of a great number of environmental problems, appearing by noxiousrneffects at various levels of the biological organization. These effects canrnreach the marine and dul?aquicoles watery ecosystems via the phenomenarnof scrubbing of the grounds and material haulage rich in potentially toxicrnresidues of pesticides. With an aim of in vivo evaluating pollution by thernpesticides via the answer of biomarqueurs at two species of mussel of bayrnof Agadir: Perna perna and Donax trunculus, an experiment of exposure ofrnthese last to 500 μg/l of three pesticides to knowing the 2,4-Drn(organochlorinated), Malathion (organophosphoré) and carbamate wererncarried out. The follow-up of the answer of the biomarqueurs:rnacétylcholinestérase (Aitch) biomarquor of neurotoxicity, Catalase (CAT)rnand Malonedialdhyde (MDA) biomarquor of oxidizing stress and GlutathionrnS-Transférase (GST) biomarquor of detoxification of hydrocarbons atrnsummer carried out at different duration during 7 days. The results revealedrnan overall coherent answer of the various biomarkers; this answer occurredrnin an early way and varies according to the type of the pesticide and thernexposure time. Indeed, the Aitch showed a significant inhibition at the twornspecies as of the first six hours (6h) of exposure and continuous until thernend of the experiment almost for all the pesticides tested. This answer isrnexplained by the sensitivity of the Aitch to the pesticide especiallyrnorganophosphorés recognized by their neurotoxic effect appearing byrninhibition of the Aitch. The CAT is induced after 12h of exposure beyond thisrnperiod a rise of the rates of MDA was recorded at the two species, this resultrnprobably testifies to a notable induction of lipoperoxydation due to the freernradicals generated by the contamination by the pesticides especially thernorganochlorinated 2,4-D and carbamate. The GST showed a variable answerrnaccording to species' and the type of the pesticide, namely an induction by