Studies On The Toxical Effect Of Cypermethrin On Carassius Auratus Linn

Cypermethrin which was a kind of pyrethroids caused severe contamination to the environment with its wide use in agriculture in recent years . This master paper used Carassius auratus Linn. as experiment animal, applied biochemiscalogy, cell biology etc. technology , studied the influences produced by cypermethrin on Carassius auratus Linn, from acute toxicity trials , accumulation and release rules , immune system , antioxidize system , and heredity effect, from the whole living, organ and cell level and molecule level evaluated the satey of cypermethrin .The results of acute toxicity revealed that 96hLC₅₀ of cypermethrin was 18.0μg·L^-1 for Carassius auratus Linn. with mean body weight 65.0g±5.0g and mean body length 14.0±1.0cm. According to the methods of biological detect, cypermethrin was a high toxic pesticide for Carassius auratus Linn..Based on the acute toxicity trial, the following concentration series below 1/2 96hLC₅₀ that were 1μg·L¹,2μg·L¹,3μg·L¹ ,5μg/L and 8μg·L¹ were established to infect Carassius auratus Linn.. Analyzing continual exposure to low dosage cypermethrin for the impact of physiochemical and hereditary of Carassius auratus Linn.. We get a conclusion that:1) Results indicated that accumulation of cypermethrin in Carassius auratus Linn, reached balance at the twentieth to twenty fifth days and the maximal enrichment coefficients of muscle and organ were 3.950 and 2.115 . Accumulation capacity of muscle was less than that of liver while cypermethrin release of muscle was quicker than that of liver.2) There were obvious pathological changes in liver of Carassius auratus Linn, after its continual exposure to cypermethrin for 30 days, but organ coefficients did not occur obvious changes. As for spleen, it did not take on any obvious changes compared with the contrast in anatomization shape and organ coefficients. The influences on lysozyme by cypermethrin in Carassius auratus Linn, were that low concentration lysozymes(2μg·L¹-5μg·L¹) had the tendency of arising first and declining after, whereas the tendency was contrary for high concentration lysozymes (8μg·L¹) . With the increasement of exposure time , all trial groups restored to natural levels at the twentieth day . Lysozemes content in serum was steady until the end of the trial and was not obviously different from the contrast. The outcome revealed that the effects on lysozemes in serum by cypermethrin was reversible for Carassius auratus Linn..3) After exposure to 1.0ug·L^-1 of cypermethrin for 30 days , GSH contents and activities of GST,CAT and MAO in muscle and liver had not any significantly difference(P>0.05), but GSH contents and activities of GST,CAT and MAO all occurred dynamic varieties after exposure to cypermethrin above 2.0 ug·L^-1 : (a) Under the cypermethrin intimidation , the tendency of GSH contents and GST activities were arising first then declining after and the variety degree in liver was bigger than that of muscle . At the end of trial, GSH content in other groups had some changes compared with the contrast except for the group of 1.0 ug·L^-1, but GST activity was different significantly from the contrast(P<0.01) , 15.71%-67.31% beneath contrast group . (b) CAT activity tendency was decreasing first then arising after and variety degree in liver was bigger than that of muscle. At the end of trial , CAT activity in other groups had some changes compared with the contrast except for the group of 1.0 ug·L^-1. CAT activity in muscle is lower 17.8% than the contrast group , the most reduction of CAT activity in organ between 51.86%-69.64% (P<0.01); (c) MAO variety was arising first, then declining and restoring at last and variety degree in liver was lower than that in muscle. At the end of trial , MAO activity in other groups had some changes compared with the contrast except for the group of 1.0 ug·L^-1.4) The results showed that continual exposure to cypermethrin above 3.0 ug·L^-1 could induce peripheral red cell to produce micronuclei . Micronuclei frequency had obvious concentration effect and time effect with cypermethrin concentration increased and exposure time prolonged.The results revealed that cypermethrin above 2.0 ug·L^-1 produced influences on physiological mechanism of Carassius auratus Linn.; For the security of aquaculture and food available , cypermethrin concentration should be below 1.0 ug·L^-1 in aquaculture for edible quality.