Monitoring of Shellfish Growing Areas - 1993

Abstract

During 1993, water and shellfish from 19 major growing areas were monitored for chemical parameters in accordance with the 1979 Council Directive 79/923/EC. At each site temperature, salinity, pH, dissolved oxygen and suspended solids measurements were taken and shellfish samples were returned to the laboratory for metal, chlorinated hydrocarbon and algal biotoxin determinations. Generally, water quality in all areas was good and conformed to the guidelines of the Directive. The highest levels of metals recorded were: cadmium in Tralee Bay (0.4 to 0.7µg/g) and Carlingford Lough (0.3 to 0.7µg/g) and lead in Wexford Harbour (0.5µg/g). Mercury in all cases was low with the exception of Cromane during November when levels of 0.3µg/g were detected. Chlorinated hydrocarbons levels were extremely low and indicate the clean nature of Irish shellfish, unpolluted by these synthetic organic compounds. Algal biotoxins were not detected in any samples.