Toxicity of long-term intake of PSP at low level from shellfish on rats / 中国病理生理杂志

ABSTRACT

AIM: In order to investigate the possible cumulative and chronic toxicity of paralytic shellfish poisoning (PSP) and provide more information on toxicity of PSP. METHODS: The sub-acute toxicity of PSP was evaluated in the rat. PSP was extracted from the seafood in market, and the toxicity of the extract was determined by mouse bioassay. The extracts in different toxicity were administrated to rats through gastrotube for 35 days. The biochemical and pathological changes in vital tissues in rats were examined by the detections of some function indexes in blood and urine and the observations under optical microscope during both the exposure period and the subsequent 10-day withdrawal term. RESULTS: No biochemical and pathological changes in tissues occurred for the control and low-dose group (4.6 ?g STX/kg), whereas some changes happened for the middle (9.2 ?g STX/kg) and high groups (18.4 ?g STX/kg). In experiment, some renal function indexes changed in the mid-dose group, and some of the cardiac, hepatic and renal functions indexes altered for the high dose group with some changes in weight of the thymus gland and spleen. What is more, the liver and kidney became indistinct with some inflammatory changes, and some muscles had ruptured for the 40% rats in high-dose group. CONCLUSION: These results suggest that long-term intake of PSP at a concentration, which doesn't exceed the threshold of standard, has some toxicity on rats, and that the toxicity of PSP has an accumulative effect. In a word, it is unsafe for us to eat frequently bivalve seafood polluted by PSP toxins.