Heavy metal toxicity in Exosphaeroma gigas (Crustacea, Isopoda) from

ERICA GIARRATANO, LAURA COMOGLIO, OSCAR AMIN

ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

ACADEMIC PRESS INC ELSEVIER SCIENCE

Año: 2007 vol. 68 p. 451 - 462

0147-6513

Acute toxicity of copper, cadmium, and zinc on isopod Exosphaeroma gigas was evaluated at 20% and 30% salinity. Six concentrations were assayed to estimate effective concentration of the toxicant that affects 50% of tested animal (EC50), while physiological responses and bioaccumulation were determined at 0.42 and 1.95 mgL1 of each metal. The following toxicity orders were obtained: CdXCu4Zn at 20% salinity and Cu4ZnXCd at 30% salinity. Copper treatments showed a reduction in oxygen consumption at 30% salinity, while an opposite trend was observed at 20% salinity. Zinc caused dissimilar effects, while in cadmium significant reduction was only registered in 0.4220% mg L1. Ammonia excretion was generally higher in treatments than control at 20% salinity. At 30% salinity, excretion did not change in relation to control or diminished. In general terms, O:N atomic ratios indicated a preponderant protein metabolism. Bioaccumulation of assayed metals was higher at lowest salinity and increased with increasing toxic concentrations. relation to control or diminished.