feed for fish and fish as food
NIFES to survey environmental toxins in crabs
For the first time, the level of environmental toxins and heavy metals in crabs from all along the Norwegian coast is to be analysed. Recent sampling has revealed high concentrations of cadmium in crabs from the County of Nordland.
“We are currently gathering samples, and a total of 475 crabs from 48 different positions all along the coast will be brought to the laboratory for analysis,” says NIFES research scientist Sylvia Frantzen.
The reason for this survey of hazardous substances in crabs from the rest of Norway is the finding of high concentrations of cadmium in crabs from Salten in Nordland. In both 2009 and 2010, the cadmium content of samples from this area has been higher than the upper limit in crab claw meat permitted by the EU and Norway. Cadmium is a toxic heavy metal that accumulates in the bodies of crustaceans, fish, other animals and humans.
Both claw meat and brown meat will be analysed for their content of heavy metals such as lead, cadmium and mercury, as well as of organic environmental toxins such as PCBs, dioxins, brominated flame retardants and perfluorates.
Since 2001, NIFES has been analysing crustaceans for a number of areas as part of a major monitoring programme on behalf of the Norwegian Food Safety Authority, the National Shellfish Production Inspection Programme.
“Our 2010 monitoring results confirmed that crabs from around Salten have high levels of cadmium,” says Frantzen.
Of the 14 samples taken in Salten in summer 2010, three had cadmium concentrations in claw meat that were beyond the permitted limit of 0.5 mg/kg wet weight. The highest level was 1.1 mg/kg, while some samples of brown meat contained as much as 19 mg/kg. Upper limits for brown meat have not been set, but the Food Inspectorate has issued a general advisory for women of child-bearing age and children not to eat crab brown meat.
Samples taken in October and November 2010 from western Norwegian waters had a much lower cadmium content.
On the basis of these 2010 results, the Food Inspectorate has isued a dietary advisory for the area between Saltfjorden and Folda, to the effect that everyone should avoid eating brown meat from edible crabs. The Food Inspectorate also advises limiting consumption of claw meat from crabs caught in this area.
NIFES have also analysed 15 samples of crab from Salten taken during the summer of 2011.
"Four of these samples contained cadmium higher than the upper limit in crab claw. The samples of brown meat also contained high levels of cadmium," says Sylvia Frantzen.