Biochemical responses and metals levels in Ruditapes decussatus after exposure to treated municipal effluents.
This study assessed the responses of biochemical biomarkers and metals levels in Ruditapes decussatus exposed to the increasing concentrations of treated municipal effluents (TME) discharged into the Tunisian coastal area. Clams were exposed to 0%, 1%, 3% and 10% for 7 and 14 day and the following biochemical responses were measured: (1) catalase activity and lipid peroxidation levels (TBARS) as oxidative stress biomarkers, (2) gluthathione S-transferase (GST) activity as a phase II conjugation enzyme; (3) cholinesterase activity (ChE) as biomarker of neurotoxicity, and (4) metallothioneins as a proteins highly induced by heavy metals. A significant uptake of Cu, Cd and Zn in digestive gland and serious biochemical alterations were observed. Thus, exposure of clams to croissant concentration of TME have the potential to increase the oxidative stress biomarkers (TBARS, CAT activity) and MT levels; and decrease ChE activity in both gills and digestive gland. Current experimental results suggest that CAT, GST, ChE activities and MT and TBARs levels in gills and digestive gland of clam R. decussatus are sensitive and suitable responses for assessing the effects of anthropogenic contaminants on the aquatic ecosystems, particularly effluent complex mixtures.
Laboratory of Biochemical and Environmental Toxicology, Higher Institute of Agriculture, Chott-Mariem, 4042-Sousse, Tunisia.
Naouel
N
Kamel
Jamel
J
Jebali
Mohamed
M
Banni
Sana
S
Ben Khedher
Lassaad
L
Chouba
Hamadi
H
Boussetta
D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D049872:Bivalvia / Q000737:chemistry* / Q000187:drug effects*; D002374:Catalase / Q000378:metabolism; D004784:Environmental Monitoring; D005880:Gills / Q000737:chemistry / Q000187:drug effects; D005982:Glutathione Transferase / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008668:Metallothionein / Q000378:metabolism; D019216:Metals, Heavy / Q000633:toxicity; D018384:Oxidative Stress / Q000187:drug effects; D014416:Tunisia; D062065:Wastewater / Q000032:analysis / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D015415:Biomarkers; D002374:Catalase; D005982:Glutathione Transferase; D008668:Metallothionein; D019216:Metals, Heavy; D062065:Wastewater; D014874:Water Pollutants, Chemical