Lack of secondary intoxification by red tide poison in the American lobster Homarus americanus.

Lobsters are able to feed on shellfish which are toxic with PSP (paralytic shellfish poisoning from Gonyaulax tamarensis) with no apparent harm to themselves, and no measurable assimilation of the poison into their tissues. Lobsters consumed food containing in excess of 1000 mug PSP. There was no impairment of respiration (oxygen consumption) measurable two to three hours after feeding, and no PSP measured in the meat of the claws and tail 48 to 120 hours after feeding. The only PSP was in the guts and contents which were measured 48 hours after feeding began.