Detection of early effects of a single herbicide (diuron) and a mix of herbicides and pharmaceuticals (diuron, isoproturon, ibuprofen) on immunological parameters of Pacific oyster (Crassostrea gigas) spat

Andrea Luna-Acosta (1, 2) , Tristan Renault (2, 3) , Hélène Thomas-Guyon (1, 2) , Nicole Faury (2, 3) , Denis Saulnier (2, 3) , Hélène Budzinski (4) , Karine Le Ménach (4) , P. Pardon (4) , Ingrid Fruitier-Arnaudin (1, 2) , Paco Bustamante (1, 2)

1 LIENSs - LIttoral ENvironnement et Sociétés
2 FREDD - Fédération de Recherche en Environnement pour le Développement Durable - FR 3097
3 AGSAE - Unité Amélioration génétique, Santé animale et Environnement
4 LPTC - Laboratoire de Physico -& Toxico Chimie des systèmes naturels

In the context of massive summer mortality events of the Pacific oyster Crassostrea gigas, the aim of this study was to investigate the early effects on genes, enzymes and haemocyte parameters implicated in immune defence mechanisms in C. gigas oysters exposed to a potentially hostile environment, i.e. to an herbicide alone or within a mixture. Following 2 hours of exposure to the herbicide diuron at 1 µg L-1, the repression of different genes implicated in immune defence mechanisms in the haemocytes and the inhibition of enzyme activities, such as laccase-type phenoloxidase (PO) in the plasma, were observed. The inhibition of superoxide dismutase (SOD) activity in the plasma was also observed after 6 and 24 hours of exposure. In the mixture with the herbicides diuron and isoproturon, and the pharmaceutical ibuprofen, catecholase-type PO activity in the plasma and the percentage of phagocytosis in the haemocytes were reduced after 6 hours of exposure. Our results showed that early effects on molecular, biochemical and cellular parameters can be detected in the presence of diuron alone or within a mixture, giving an insight of its potential effect in situations that can be found in natural environments, i.e. relatively high concentrations for short periods of time.

Mots clés: bivalve; pollution; gene expression; laccase; superoxide dismutase; phagocytosis

Domaines: Ecotoxicologie

Andrea Luna-Acosta, Tristan Renault, Hélène Thomas-Guyon, Nicole Faury, Denis Saulnier, et al.. Detection of early effects of a single herbicide (diuron) and a mix of herbicides and pharmaceuticals (diuron, isoproturon, ibuprofen) on immunological parameters of Pacific oyster (Crassostrea gigas) spat. Chemosphere, 2012, 87 (11), pp.1335-1340. ⟨10.1016/j.chemosphere.2012.02.022⟩. ⟨hal-00686855⟩