Trace Metal Concentrations in Various Fish Species Landed at Selected Irish Ports, 2003

Abstract

The Marine Institute sample a range of finfish species landed at major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 2003, a total of 45 samples from 22 different species of finfish were collected from five major Irish fishing ports and analysed for total mercury concentration in the edible tissue. The concentration of mercury ranged from less than the limit of quantitation (0.03 mg/kg wet weight) to 0.60 mg/kg wet weight with a mean and median of 0.08 and 0.06 mg/kg respectively. The maximum level was found in a dogfish sample (species tentatively identified as Lesser Spotted Dogfish) from Howth. It is most likely that the fish from which this sample was taken were destined for whelk bait and as such there are no human health implications. The remainder of the mercury levels were within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EU (1 mg/kg for selected species). This survey confirms previous studies, which show that Irish seafoods are effectively free from mercury contamination. A total of 20 samples were analysed for lead and cadmium. Overall, the levels of lead and cadmium detected in the edible portion of the fish were low and well within the standard values of 0.20 and 0.05 mg/kg wet weight respectively set by the EU. Randomly selected samples were also analysed for other trace metals. There are no internationally agreed standards or guidelines available for the remaining trace metals in fishery products. Therefore results are compared with the strictest standard or guidance value for fish tissue, which are applied by contracting countries to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed.