Pollutants can be found in any foods that contain fats. These pollutants are mainly dioxins and polychlorinated biphenyls [PCBs]. Women and girls are particularly advised to be careful about the amount of oily fish they eat as these pollutants can build up in their bodies over a period of time and cause damage to the development of an unborn baby. The problem with dioxins and PCBs is that they become stored in our bodies so, even if a woman does cut down on the amount of oily fish she eats prior to becoming pregnant, this will not alter the amount she already has stored in her body. The best advice is for girls to consume only small quantities of oily fish long before they are even of child bearing age.
Other fish which have been shown to have similar levels of pollutants as oily fish are turbot, halibut, dog fish/huss, sea bass and sea bream. Fish lovers would be better advised to increase the amount of red snapper, haddock, hake and coley they eat and reduce the amount of fish that are prone to dioxins and PCBs.
Langoustines, also known as Dublin Bay prawns or Norway lobsters are particularly low in fat and high in minerals, providing an excellent source of protein. Other shellfish, including crab, lobster, mussels, squid, cockles, clams and scallops also provide a low fat meal, high in both protein and minerals.
Many shellfish do contain harmful bacteria and viruses, especially if they are what is known as ‘filter feeders’ where potentially polluted water passes through them due to the water conditions where they live. Because of this it is recommended that people who could be at risk, such as the elderly or anybody with compromised immunity, do not attempt to eat raw shellfish as it could lead to food poisoning. As most shellfish is eaten after being cooked this is not often a problem.
Shellfish allergy is quite a common allergy, often causing quite pronounced reactions and, despite proper cooking, somebody with an allergy to fish or shellfish will always exhibit symptoms. Oysters, which are usually eaten raw, are known to often contain a Norovirus which can cause nausea, dehydrating diarrhoea and abdominal pain, together with headaches and fever. Partially cooked shellfish can cause Hepatitis A which is extremely contagious and easily spread through uncooked foods such as salads. The problem with Hepatitis A is that it often does not show up for several weeks after a person is infected, leaving them as an unknowing carrier who is at general risk to the public.