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Shellfish picking

published on 04/16/2008
A popular activity along France’s coast, shellfish picking combines relaxation with food-loving pleasure. Shellfish have undeniable nutritional value and are often used in fine cuisine. However, their health profile can be influenced by human activity. Considering the way they live and eat (by filtering sea water), shellfish, in particular bivalve filterers (mussels, oysters, clams, scallops, etc.) can become a concentration of all of the pollutants present in the environment. This can make them inappropriate to eat, when the environment is polluted.
An appropriate monitoring system has been set up to ensure that they can be eaten risk-free.
The three types of pollutants that shellfish can contain are: pathogens (bacteria and viruses), toxic phytoplankton and chemical compounds (heavy metals, hydrocarbons, pesticides).
shellfish picking
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The shellfish family is composed of gastropods, with a single-piece shell (sea snails, whelks, barnacles, abalone, etc.) and bivalves, with a shell made of 2 distinct parts (oysters, mussels, clams, scallops, etc.).
Shellfish have an especially high mineral element content (calcium, magnesium) and oligo-elements (zinc, iron, iodine, selenium). They are also high in certain vitamins, like vitamin B, vitamin D and vitamin E. Shellfish are low in calories (60 to 80 KCAL/100g of meat), high in protein (10 to 15 g/100 g) and low in fat (1 to 2 g/100 g). Like fish, they contain lipids made up primarily of fatty acids that are good for the cardiovascular system. Their cholesterol content is on par with that of meats (50 to 80 mg/100g).
Shellfish can concentrate up to 100 times the bacterial and virus content present in seawater, thereby explaining why it can be harmful to your health to eat shellfish from polluted waters. They also contain high concentrations of toxic plankton, chemical compounds such as heavy metals (lead, mercury, cadmium) and certain organic compounds (hydrocarbons, polychlorobiphenyls – PCBs, tributyl tin – TBT, certain pesticides, etc.).