The government regulates the beds and checks the oysters that are harvested for any evidence of contamination. In simplest terms, the oil migrated mostly to the east of the Mississippi Delta and roughly half the oyster beds and shrimping grounds were to the west and unaffected. Beyond that, some of the areas of early concern proved not to have significant contamination and were re-opened. I'm sure that continues in a state of some flux.
If you don't trust the government, consider that the last thing this industry wants or needs is publicity that they are marketing bad product. Finally, with everybody sensitive to the issue, there has been no evidence or other reason to question the safety of Louisiana seafood. Not even any rumors of people getting sick.
If, in the face of all the evidence, you are still worried, you should probably just do yourself a favor and eat something other than seafood. There's plenty of good food in NOLA that doesn't come from the water.
post edited by BT - 2011/02/15 00:58:36