Éditeur(s) : HAL CCSD Springer Verlag
Résumé : International audience
The release of polycyclic aromatic hydrocarbons (PAHs) into the environment has increased very substantially over the last decades. PAHs are hydrophobic molecules which can accumulate in high concentrations in sediments acting then as major secondary sources. Fish contamination can occur through contact or residence nearby sediments or though dietary exposure. In this study, we analyzed certain physiological traits in unexposed fish (F1) issued from parents (F0) exposed through diet to three PAH mixtures at similar and environmentally relevant concentrations but differing in their compositions. For each mixture, no morphological differences were observed between concentrations. An increase in locomotor activity was observed in larvae issued from fish exposed to the highest concentration of a pyrolytic (PY) mixture. On the contrary, a decrease in locomotor activity was observed in larvae issued from heavy oil mixture (HO). In the case of the third mixture, light oil (LO), a reduction of the diurnal activity was observed during the setup of larval activity. Behavioral disruptions persisted in F1-PY juveniles and in their offspring (F2). Endocrine disruption was analyzed using cyp19a1b:GFP transgenic line and revealed disruptions in PY and LO offspring. Since no PAH metabolites were dosed in larvae, these findings suggest possible underlying mechanisms such as altered parental signaling molecule and/or hormone transferred in the gametes, eventually leading to early imprinting. Taken together, these results indicate that physiological disruptions are observed in offspring of fish exposed to PAH mixtures through diet.
ISSN: 0944-1344

hal-01121865
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01121865
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01121865/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01121865/file/Exposures%20of%20zebrafish_accepted.pdf
DOI : 10.1007/s11356-015-4157-8

Éditeur(s) : Springer
Résumé : The French Atlantic coast contains large highly productive intertidal mudflats that are colonised by juveniles of numerous flatfish species, including the common sole (Solea solea, L.). These ecosystems are also heavily exploited by the shellfish farming industry. Intensive bivalve culture is associated with substantial biodeposition (1-6 t-dw ha(-1) day(-1)), which directly or indirectly contributes to increase exopolysaccharide (EPS) concentrations at the interface between water column and seabed. EPS are long-chain molecules organised into colloids, which influence rheological properties of water, particularly viscosity. Increased water viscosity had consequences for ventilatory activity of juvenile flatfish, whereby the minimal pressure required to ventilate the medium increases directly with EPS concentration. Moreover, the critical EPS concentration ([EPS](crit)) at which water was no longer able to flow through the branchial basket ranged from almost nil to over 30 mg l(-1), depending on species and size. [EPS](crit) was lower in small individuals and individuals from species with high metabolic rates (turbot and plaice). These differences may depend upon gill and bucco-branchial cavity morphometrics. The ventilatory workload of sole increased with viscosity to a maximum at 2 mg EPS l(-1). Viscosity might, therefore, be a limiting factor for flatfish post larvae, which colonise the intertidal mudflats, depending upon their size and species. EPS concentrations in the field can reach 15 mg l(-1). A selective effect is conceivable but remains to be estimated in the field.
Marine Biology (0025-3162) (Springer), 2007-09 , Vol. 152 , N. 4 , P. 803-814

Droits : 2007 Springer
http://archimer.ifremer.fr/doc/2007/publication-2801.pdf
DOI:10.1007/s00227-007-0731-z
http://archimer.ifremer.fr/doc/00000/2801/