The standard test for infection with the coronavirus looks for a genetic fingerprint. Laboratory errors, including contamination, can lead to false results, a problem seen with environmental testing.
Researchers said the discovery of pharmaceuticals and illicit drugs in local harbors is not uncommon, but the agency noted that this is the first time that oxycodone has been found in shellfish.
After decades with no sign of a lethal neurotoxin, the algae that produces it is now plaguing the warming waters of the Gulf of Maine, forcing unprecedented closures in shellfish harvesting.
