Heavy metal toxicity in Exosphaeroma gigas (Crustacea, Isopoda) from the coastal zone of Beagle Channel

GIARRATANO; COMOGLIO; AMIN

ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY

Elsevier

Año: 2006

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.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.1 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.XCu4Zn 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.% 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.20% 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.% 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.