Inorganic trace elements in organisms in NW Iceland




Helga Gunnlaugsdóttir, Guðjón Atli Auðunsson, Guðmundur Víðir Helgason, Rósa Jónsdóttir, Ingibjörg Jónsdóttir, Þuríður Ragnarsdóttir, Sasan Rabieh

Supported by:

AVS Fisheries Research Fund, Fisheries Research Institute, Matís

Inorganic trace elements in organisms in NW Iceland

The purpose of the study was to seek explanations for the uniqueness of NV targets, especially in Arnarfjörður, with respect to inorganic trace elements, especially cadmium, in organisms. For this purpose, the concentration of trace elements in samples of mussels (Mytilus edulis), scallops (Chlamys islandica) and sea sediments was measured in several places around Iceland, with special emphasis on the collection of samples on NW tickets. The main results of the project are that the concentration of cadmium in mussel samples from Arnarfjörður is generally considerably higher than in other samples taken from mussels on NV tickets and this difference is statistically significant (T-test, α = 0.05 (5%)). There is also a tendency for the concentration of iron, copper, manganese and zinc to be lower in mussels in Arnarfjörður than in other fjords in the north-west, and this difference is most noticeable for iron and zinc. The results show that the concentration of cadmium in mussels from Arnarfjörður is above the EU maximum values for mussels in 9 samples out of 10, in addition there are samples of mussels from cultivation belts from Hestfjörður in Ísafjarðardjúpur and Ósafjörður (in from Patreksfjörður) above the EU limit (1.0 mg / kg wet weight for sandwiches). Mussel samples from Dýrafjörður, Seyðisfjörður in Ísafjarðardjúpur and Patreksfjörður by Sandoddi are also very close to the EU border. The amount of trace elements in sediments on NV fishing grounds seems to be very similar to previous measurements of trace elements in Icelandic sea sediments in these areas. This indicates that the explanation for the high concentration of cadmium in mussels from Arnarfjörður is probably not to be found in the higher concentration of cadmium in sediments in this area. The results of the project provide information on the uniqueness of Icelandic waters in terms of inorganic trace elements. Such information and scientific data are a prerequisite for Icelanders to be able to influence decision-making when setting maximum values for food, for example in the EU. The results of the project have already been used to influence the increase in EU maximum levels for cadmium in sandwiches and have been sent to EFSA for data collection on cadmium in food.

The aim of this research was to investigate the unique position of the territorial waters around NW-Iceland, especially Arnarfjörður, with respect to trace elements, particularly cadmium, in biota. In order to achieve this goal, trace elements in blue mussels (Mytilus edulis), scallops (Chlamys islandica) and sediments around Iceland were analyzed, with special emphasis on sampling in the NW-Iceland area. The main results from this research indicate that cadmium levels are statistically higher in blue mussels from Arnarfjörður compared to other areas in NW-Iceland (T-test, α = 0.05 (5%)). In contrast with cadmium, the iron, copper, manganese and zinc concentrations were lower in the blue mussels from Arnarfjörður in comparison with other areas in NW-Iceland. This difference was most obvious with regard to iron and zinc. The cadmium level in blue mussels from Arnarfjörður, Hestfjörður in Ísafjarðardjúp and Ósafjörður exceeds the maximum cadmium level (1.0 mg / kg wet weight) set by the European commission (EC) for Bivalve molluscs. The cadmium level in blue mussels from Dýrafjörður, Seyðisfjörður in Ísafjarðardjúpi and Patreksfjörður are also close to the maximum cadmium level set by EC. The results for trace elements in sediments from Arnarfjörður do not however explain the high levels of cadmium observed in blue mussels from this area.

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