Biotoxicity Effect Studies On Heavy Metals (Copper, Zinc And Mercury) In Spinibarbus Sinensis

Heavy metal is the principal pollutant in the river, people follow the bane action of fish closely day by day. People understand more knowledge about single toxicity of chemical substances at the present, but grasping the action and mechanism of multiple contamination's joint toxicity is not enough. The experiment used Spinibarbus sinensis with 4.5-5.6cm stature as the trier, and researched the biotoxicity of the heavy metal to Spinibarbus sinensis, included single factor acute toxicity experiment, joint acute to xicity experiment and subacut acute toxicity experiment, subacute acute toxicity experiment researched the influence of pollutant to fish's Enzymes and DNA. The results showed:1. Single factor acute toxicity experimentUsed method of static state, 96hours' half lethal concentration of Copper, Zinc and Mercury on Spinibarbus sinensis was 0.534mg/L, 10.13 mg/L and 0.141 mg/L and safe concentration was 0.053 mg/L, 1.013 mg/L, 0.014 mg/L, So we could reach a conclusion that the magnitude of toxicity is Hg²⁺ >Cu²⁺>Zn²⁺. And the half lethal concentration presented the going down tendency along with the experiment's time. 2. Joint acute toxicity experimentOn the basis of single factor acute toxicity experiment, joint acute toxicity experiment with three assembling of Cu²⁺-Hg²⁺, Cu²⁺-Zn²⁺, Hg²⁺-Zn²⁺ were carrying out. Regarding 96hLC₅₀ (96hours' half lethal concentration) as a toxicity unit, the experiment set up 6 concentration gradient and everyone's sum toxicity is 1. The results showed: the joint acute toxicity of Zn²⁺-Hg²⁺, Cu²⁺-Zn²⁺ were synergy, but the joint acute toxicity of Cu²⁺-Hg²⁺ was antagonism when Cu²⁺: Hg²⁺=0.2:0.8, the effect of Cu²⁺:Hg²⁺=0.4:0.6 was additive action, and the effect of toxicity were synergy with increasing the proportion of Cu²⁺.3. Subacute acute toxicity experiment5%, 10% and 20% of 96hours' half lethal concentration were taken to be 3 experiment groups. The experiment carried out 28days, half of the experiment liquor could be replaced by new liquor every 3 days and fishes were be feeded once every day. The samples were gathered at 7^th, 14^th, 21^th and 28^thday. The result testified, the effect of Cu²⁺, Zn²⁺ and Hg²⁺ on the GPT and GOT enzyme activity of Spinibarbus sinensis gill was inhibition, the GPT enzyme activity of gill reached minimum value at 28^th day, in which the suppression ratio of 2.026 mg/L Zn²⁺ was maximum and reach 57.45%, so the inhibition sequence of heavy metal on GPT enzyme activity of gill was Cu²⁺2+2+. At the same toxicity, compare Hg²⁺ with Cu²⁺ and Zn²⁺ has stronger inhibition on the GOT enzyme activity, the suppression ratio of the gill GOT enzyme activity at 0.028 mg/L Hg²⁺ was maximum and reached 62.68%.With the level of the heavy metal ion increasing, the inhibition of the ACP and AKP enzyme activity become increased, but the inhibition of the AKP enzyme activity increased little, especially, the enzyme activity of AKP has different level of ascending at 21th day. And the ACP enzyme activity don't become increasing by the experiment increasing either, this may be the AKP and ACP enzyme activity is more sensitive, which be to keep down at the preceeding of the experiment<7^thd). Heavy metal on the SOD enzyme activity is also inhibition, but the effect of increasing is small, can't reach markedness level, so the Cu²⁺, Zn²⁺ and Hg²⁺ ion can't reach the markedness effect on the SOD enzyme activity.The heavy metal ion on DNA damage appear the ascending trend, Zn²⁺ and Cu²⁺ on DNA damage almost reach third class and the damage ratio achieve 100% after 7^th day. The discrepancy is not markedness after 21th day, the max is 1.98 on 1.013mg/L Zn²⁺ at 21^th day. 2.026mg/L Zn²⁺ is maximal damage on heptopancreas DNA and 0.007mg/L Hg²⁺ is lowest, the sequence is Zn²⁺>Cu²⁺>Hg²⁺.Through experiment, we find out SCGE technique have sensitive, high-speed, immediante, reliable etc merits on heavy metal on the damage of Spinibarbus sinensis heptopancreas DNA, which can detect the DNA rupture and reflect inheritance toxicity by low dose, so regarding it as biomarker in inchoate biolog...