The Acute Toxicity and Bioaccumulation of Deltamethrin in Four Species of Mariculture Organisms

Abstract:

The acute toxicity and bioaccumulation of deltamethrin was studied in four species of mariculture organisms including the crustaceans Portunus pelagicus and Marsupenaeus japonicus, and the bivalve Meretrix meretrix and Ruditapes philippinarum. The results indicated that there were significant positive correlations between the mortality rate of the mariculture organisms and the concentration and exposure time of deltamethrin. The LC50 values at 24 h, 48 h and 96 h for the crustacean P. pelagicus were 2.07×10-4, 1.70×10-4 and 1.10×10-4 mg/L respectively, and the values for M. japonicas were 7.32×10-4, 3.90×10-4 and 1.43×10-4 mg/L. The safe concentrations for these two species were 3.44×10-5 mg/L and 3.32×10-5 mg/L respectively. The LC50 values at the 3 time points for the bivalves M. meretrix were 1.52, 0.30 and 0.27 mg/L respectively, and for R. philippinarum they were 0.67, 0.11 and 0.06 mg/L respectively. The safe concentrations for these two species were 3.51× 10-3 mg/L and 9.50×10-4 mg/L respectively. Obviously the two crustacean species were more sensitive to deltamethrin than the bivalves. Next, the bivalves M. meretrix and R. philippinarum were exposed to the seawater containing deltamethrin at average concentrations of 0.86–0.05 mg/L and 0.37–0.03 mg/L respectively for 24–96 h, and we found that the accumulation coefficients of deltamethrin in these two species were 2.57–12.40 and 3.03–27.85 respectively. The accumulation rate of deltamethrin in the two bivalve species was positively corelated with the exposure time of deltamethrin, but negatively correlated with the concentration of deltamethrin. There were significant differences in sensitivity and accumulation rate of deltamethrin between different species of marine aquaculture organisms.