Difference between revisions of "Levels of PCBs and organochlorine pesticides in various benthic species in the Belgian North sea and the Western Scheldt estuary"

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<u>'''Content of the study'''</u>
 
<u>'''Content of the study'''</u>
  
The study measured concentrations of PCBs and OCPs in crabs, starfish, shrimp, sand goby, sole, plaice, whiting and bib in the Western Scheldt estuary and in the Belgian part of the North Sea. This to evaluate their suitability for human consumption, except for sand goby and starfish, which were monitored as sentinel species. As it's known that PCBs and OCPs tend to accumulate in lipids, the lipid content of the animals was also examined.
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The study measured concentrations of PCBs and OCPs in crabs, starfish, shrimp, sand goby, sole, plaice, whiting and bib in the Western Scheldt estuary and in the Belgian part of the North Sea. This was done, to evaluate their suitability for human consumption, except for sand goby and starfish, which were monitored as sentinel species. As it's known that PCBs and OCPs tend to accumulate in lipids, the lipid content of the animals was also examined.
  
 
<u>'''Main results of the study'''</u>
 
<u>'''Main results of the study'''</u>

Revision as of 14:57, 17 July 2009

Context of the study

Both PCBs and organochlorine pesticides (OCPs) are known to be very persistant, to bioacumulate in lipids and to biomagnify. They are very wide spread in the environment and in biota. Many people enjoy sea food, therefore, to evaluate our exposure to these toxic chemicals, it's necessary to determine their concentrations in these animals. [1]

Content of the study

The study measured concentrations of PCBs and OCPs in crabs, starfish, shrimp, sand goby, sole, plaice, whiting and bib in the Western Scheldt estuary and in the Belgian part of the North Sea. This was done, to evaluate their suitability for human consumption, except for sand goby and starfish, which were monitored as sentinel species. As it's known that PCBs and OCPs tend to accumulate in lipids, the lipid content of the animals was also examined.

Main results of the study

Shrimp had the lowest concentrations of PCBs: 1.5-40 ng/g (in ng PCB / g total tissue). Bib and whiting had the highest concentrations of PCBs: 810 - 3200 ng/g and 780 - 3100 ng/g respectively. Shrimp probably had these lower concentrations because of their lower fat content (0,6% compared to 50% for bib) and because of their more pelagic life style. Shrimp live slightly above the seabed, which results them having less contact with the sediment than the other species in this study. Furthermore shrimp occupy a lower trophic level (they eat opossum shrimp and amphipods) than most other species of the study. Crabs had a higher PCB content because as scavengers they eat much decaying organic material which can be heavily polluted.

Furthermore PCB levels were much higher in all species from the Western Scheldt estuary than in those from the Belgian part of the North Sea.

OCPs were present at much lower concentrations than PCBs: ranging from 0.4 - 1.7 ng/g in shrimp to 22 - 410 ng/g in whiting. Here also tended concentrations in animals from the Western Scheldt to be higher than in those from the Belgian part of the North Sea.

The study concluded that species found in the Western Scheldt estuary were highly contaminated and that this appears to be related to proximity to Antwerp. The study could not determine whether the higher concentrations found in animals close to Antwerp only reflected historical pollution or also reflected a present contamination.[1]


References