Trace Metal Incorporation in Otoliths of Black Bream (Acanthopagrus butcheri Munro), an Indicator of Exposure to Metal Contamination

Ranaldi, Melinda M.; Gagnon, Marthe M.

Trace Metal Incorporation in Otoliths of Black Bream (Acanthopagrus butcheri Munro), an Indicator of Exposure to Metal Contamination

2008

Ranaldi, Melinda M. | Gagnon, Marthe M.

Otoliths of black bream (Acanthopagrus butcheri) collected from the Swan River Estuary were analysed by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) to measure concentrations of 14 trace metals. Trace metal concentrations in the otoliths may be related to the environmental exposure history of fish to contamination. The following metal isotopes were investigated: aluminium (²⁷Al), calcium (⁴⁴Ca), manganese (⁵⁵Mn), iron (⁵⁷Fe), copper (⁶⁵Cu), zinc (⁶⁶Zn), strontium (⁸⁸Sr), cadmium (¹¹¹Cd), tin (¹²⁰Sn), barium (¹³⁸Ba), mercury (²⁰²Hg), lead (²⁰⁸Pb) and the metalloids arsenic (⁷⁵As, ⁷⁷As) and selenium (⁸²Se). Significant differences in otolith trace metal composition were found between sampling sites. Lead and ⁵⁷Fe were consistently lower in downstream fish relative to upstream fish, while ⁸⁸Sr varied with the salinity gradient in the urban estuary. Lead and ⁵⁷Fe followed similar patterns within the otoliths, and appeared to provide the best discriminatory power for relating otolith metal concentration to the environmental history of the fish.

Afficher plus [+]