• Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters 2001

      Glynn, D; Tyrrell, L; McHugh, B; Rowe, A; Monaghan, E; Costello, J; McGovern, E (Marine Institute, 2003)
      Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water, trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. In 2001, a total of 23 samples from 20 different shellfish sites were analysed for trace metals and chlorinated hydrocarbons. The median concentration of mercury in shellfish sampled in 2001 was <0.03 mg/kg wet weight, with a maximum of 0.04 mg/kg wet weight which is well within the maximum limit of 0.50 mg/kg wet weight for mercury in bivalve molluscs set by the EU. The levels of lead and cadmium detected were low, with means of 0.20 and 0.24 mg/kg wet weight and maxima of 0.37 and 0.74 mg/kg wet weight respectively, also within the respective maximum levels of 1.50 and 1 mg/kg wet weight set by the EU. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in shellfish. However these results were compared with the strictest standard or guidance values for shellfish, which are applied by contracting countries to OSPAR, and were found to be well below the strictest values listed. This is evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. This survey confirms previous studies (Glynn et al., 2003; McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals and chlorinated hydrocarbons is low in Irish shellfish aquaculture.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters 2002

      Glynn, D; Tyrrell, L; McHugh, B; Monaghan, E; Costello, J; McGovern, E (Marine Institute, 2004)
      Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water and trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. In 2002, a total of 24 samples from 22 different shellfish sites were analysed for chlorinated hydrocarbons and trace metals, including nickel and silver. The median concentration of mercury in shellfish sampled in 2002 was <0.03 mg/kg wet weight, which is well within the European maximum limit of 0.50 mg/kg wet weight for mercury in bivalve molluscs. The levels of lead and cadmium detected were low, with means of 0.16 and 0.33mg/kg wet weight and maxima of 0.34 and 0.66 mg/kg wet weight respectively, also within the respective European maximum levels of 1.50 and 1 mg/kg wet weight. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in shellfish. Therefore, these results were compared with the strictest standard or guidance values for shellfish, which are applied by contracting countries to the OSPAR Convention, and were found to be well below the strictest values listed. This is evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. This survey confirms previous studies (Glynn et al., 2003a, 2003b; McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals and chlorinated hydrocarbons is low in Irish shellfish aquaculture.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters, 1997-1999

      McGovern, E; Rowe, A; McHugh, B; Costello, J; Bloxham, M; Duffy, C; Nixon, E (Marine Institute, 2001)
      In accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs, the Marine Institute collected water and shellfish samples from major shellfish growing areas and analysed for physicochemical parameters, trace metal levels and chlorinated hydrocarbon concentrations. Since, with the exception of mercury, there are no currently applicable European standards for the concentration of these contaminants in shellfish, the levels were compared with the available standards and guidance values for human consumption, as compiled by the Oslo and Paris Commission (OSPAR) countries. As in previous years, the water quality from shellfish growing areas was good and conformed to the guidelines and requirements of the Directive. Petroleum hydrocarbons were not observed in any of the shellfish waters or as deposits on the shellfish. Chlorinated hydrocarbon levels were very low, evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. Trace metal levels were consistently low with the exception of cadmium in oyster tissue, which was slightly elevated in the 1999 samples from Clew Bay, Inner Tralee Bay, Aughinish Limerick and Kilkieran. However these levels did not exceed the Dutch human consumption standard value or the EU maximum limit of 1.0 mg/kg wet weight due to apply from 2002. This survey confirms previous studies which show Irish shellfish products are effectively free from trace metal and chlorinated hydrocarbon contamination.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Shellfish from Irish Waters, 2000

      Glynn, D; Tyrrell, L; McHugh, B; Rowe, A; Costello, J; McGovern, E (Marine Institute, 2003)
      Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water, trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. EU Commission Regulation 466/2001/EC (as amended by Regulation 221/2002/EC) came into effect on 5th April 2002. This set maximum levels for mercury, cadmium and lead in bivalve molluscs of 0.5mg/kg, 1mg/kg, and 1.5mg/kg wet weight respectively. In the absence of EU standards for other contaminants in shellfish, monitoring results have been compared to strictest guidance or standard values available in other OSPAR Convention contracting countries. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. Levels of chlorinated hydrocarbons and trace metals in shellfish tissue were very low in all areas, which is evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. This survey confirms previous studies (McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals and chlorinated hydrocarbons is low in Irish shellfish products.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Various Fish Species Landed at Selected Irish Ports, 1997-2000

      Tyrrell, L; Glynn, D; Rowe, A; McHugh, B; Costello, J; Duffy, C; Quinn, A; Naughton, M; Bloxham, M; Nixon, E; et al. (Marine Institute, 2003)
      The Marine Institute samples a range of finfish species landed at five major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 1997 – 2000, a total of 112 samples from 23 different species of finfish were collected from five major Irish fishing ports and analysed for total mercury concentration in the edible. The concentration of mercury ranged from 0.03 to 0.18 mg/kg wet weight in 1997, <0.03 to 0.19 mg/kg wet weight in 1998, <0.03 to 0.29 mg/kg wet weight in 1999 and 0.03 to 0.33 mg/kg wet weight in 2000. These levels are well within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EC. This survey confirms previous studies, which show that Irish seafoods are effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. 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. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standard or guidance value for fish tissue, which are applied by contracting parties to OSPAR. The levels of these additional contaminants are well below the strictest values listed.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Various Fish Species Landed at Selected Irish Ports, 2001

      Tyrrell, L; Glynn, D; McHugh, B; Rowe, A; Monaghan, E; Costello, J; McGovern, E (Marine Institute, 2003)
      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 2001, a total of 44 samples from 20 different species of finfish were collected from six 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 0.42 mg/kg wet weight with a mean and median of 0.09 and 0.07 mg/kg respectively. These levels are within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EC (1 mg/kg for selected species). This survey confirms previous studies, which show that Irish seafood is effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. 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. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standard or guidance value for fish tissue, which are applied by contracting parties to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed.
    • Trace Metal and Chlorinated Hydrocarbon Concentrations in Various Fish Species Landed at Selected Irish Ports, 2002

      Tyrrell, L; Twomey, M; Glynn, D; McHugh, B; Joyce, E; Costello, J; McGovern, E (Marine Institute, 2004)
      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 2002, a total of 38 samples from 20 different species of finfish were collected from five major Irish fishing ports and analysed for total mercury concentration in the edible tissue (Common names and species names are listed in Appendix 3). The concentration of mercury ranged from less than the limit of quantitation (0.03 mg/kg wet weight) to 0.46 mg/kg wet weight with a mean and median of 0.09 and 0.06 mg/kg respectively. These levels are 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 seafood is effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. 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. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standards or guidance values for fish tissue, which are applied by contracting parties to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed.
    • Trace Metal Concentrations in Shellfish from Irish Waters, 2003

      Boyle, B; Tyrrell, L; McHugh, B; Joyce, E; Costello, J; Glynn, D; McGovern, E (Marine Institute, 2006)
      In accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs, water samples from major shellfish growing areas were tested for physicochemical parameters and shellfish were tested for trace metal levels. In 2003, a total of 30 samples were analysed for trace metals. All mercury concentrations measured were below or close to the limit of quantification, 0.03 mg/kg wet weight, which is well within the European maximum level of 0.50 mg/kg wet weight for mercury in bivalve molluscs. Levels of lead were typically low, with a mean of 0.26 mg/kg wet weight and maxima of 1.04 mg/kg wet weight, also below the respective European maximum level of 1.50 mg/kg wet weight. In addition, levels of cadmium were all below the European maximum level of 1 mg/kg wet weight, though the level of cadmium determined at Castlegregory in Tralee Bay was 0.97 mg/kg, close to the European limit. Castlegregory has not been included in the sampling programme since 1994, but will be included in future monitoring. There are no internationally agreed standards or guidelines available for the remaining trace metals in shellfish. A compilation by the OSPAR Commission of standard and guidance values applied by member states of OSPAR indicated the Spanish standard for copper in shellfish of 20 mg/kg wet weight to be the strictest available. This excludes oysters for which a higher standard of 60 mg/kg wet weight has been set, as oysters accumulate copper to higher levels. All copper results were within these Spanish standards. The results obtained provide evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. This survey confirms previous studies (Glynn et al., 2004, 2003a, 2003b; McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals is low in Irish shellfish aquaculture.
    • Trace Metal Concentrations in Various Fish Species Landed at Selected Irish Ports, 2003

      Tyrrell, L; McHugh, B; Glynn, D; Twomey, M; Joyce, E; Costello, J; McGovern, E (Marine Institute, 2005)
      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.
    • Winter Nutrient Monitoring of the Western Irish Sea – 1990 to 2000

      McGovern, E; Monaghan, E; Bloxham, M; Rowe, A; Duffy, C; Quinn, A; McHugh, B; McMahon, T; Smyth, M; Naughton, M; et al. (Marine Institute, 2002)
      Winter nutrient concentrations in the western Irish Sea have been monitored annually from 1990 to 2000. Surface samples have been taken between Dundalk Bay and Carnsore Point and analysed for total oxidised nitrogen (TOxN), ortho-phosphate (ortho-P), silicate and salinity. More recently monitoring has been extended into the Celtic Sea. Data from this monitoring programme are presented in detail, along with comparisons to existing data sets. The spatial distribution of nutrients and salinity are presented for each year in contour or classed plots (depending on sample coverage for the particular year). Salinity values were representative of those expected in the Irish Sea and TOxN, ortho-P and silicate values were in general agreement with previous studies. A short summary of studies on nutrient levels in estuaries on the western Irish Sea is presented. In addition, riverine input data supplied by the Environmental Protection Agency (EPA) is used to evaluate the relative magnitude of nutrient inputs from riverine and oceanic sources. Nutrient concentrations are considered using an ecological quality objectives (EcoQOs) approach, proposed as part of the Oslo Paris Convention’s (OSPAR) ‘Common Procedure for Identification of the Eutrophication Status of the Maritime Area’, in partial consideration of the trophic status of the western Irish Sea. Although there is evidence for nutrient enrichment in some estuarine waters and possibly to a lesser extent in some coastal waters, there is little evidence for generally elevated nutrient levels in coastal and offshore waters in the western Irish Sea. Salinity regression curves were calculated for TOxN and ortho-P values in order to generate salinity-normalised concentrations for trend determinations. Regression and trend analysis were carried out on the sample area as a whole and also on regions defining the north, mid, and south western Irish Sea. Trend analysis has been performed, based on nutrient-salinity regressions, using Trend-Y-Tector. A decrease in TOxN over the study period (ranging from 4 to13%) is observed in all regions analysed with the exception of the south west Irish Sea, where a 5% increase was indicated. Analysis of trends in ortho-P concentration showing decreasing trends ranging from 20 to 33%. On visual examination, trends in TOxN are not as intuitively apparent as trends in ortho-P concentrations, therefore it may not be prudent to draw conclusions from them at this stage. Trend analysis of riverine inputs shows an increase in TOxN by 17% and no apparent trend in ortho-P levels. These trends are not consistent with trends observed in the Irish Sea. On the basis of this assessment, it is recommended that this monitoring be continued. The design of future nutrient monitoring surveys is considered, with a view to improving the efficacy of the monitoring regime.