Study Of The Toxicity Of BTri And5-MBTri On Aquatic Organism

The thesis’s studying objects are Benzotriazole and5-methyl-benzotriazole, andthe acute toxicity experiment carried on Scenedesmus oblipuus Daphnia magnaMoina Cyclops Radix Chionomus Limnodrilus hoffmeisteri Ctenopharyngodonidellus Poecilia Brachydanio rerio Bufo bufogargarizans Rana nigromaculatta12kinds of aquatic ecosystem organisms, calculating the LC50and EC50toxicityvalues to compare the toxicity of both substances. Meanwhile, refer to water qualitycriteria evaluation method of the U.S. Environmental Protection Agency,calculatedthe water quality benchmark data of the two kind of important industrial corrosioninhibitor benzotriazole and5-methyl benzotriazole. Provided foundation scientificcriteria data to formulation of chemicals in China’s water quality.In addition, this paper also try breeding experiments to Daphnia magna for21days and analyze the productive capability of Daphnia magna during long low-doseexposure, summarize the impingement of the two substances on the reproduction ofDaphnia magna populations. Compare the results with the theoretical value of thechronic toxicity which calculated through acute toxicity test and analyze itsapplication reliability in formulating water quality which will lay the foundation forfuture work.Studies have shown that the toxicity of5-methyl benzotriazole was significantlyhigher than benzotriazole. According to double value of water quality criteria which isthe standard method of USEPA, We can learn the result that the respective waterquality criteria of Benzotriazole is CMC=12.43mg/L CCC=5.68mg/L and5-methyl benzotriazole is CMC=7.00mg/L CCC=0.45mg/L. According to theexperiment to Daphnia magna for21days, the NOEC of benzotriazole on productivecapability of Daphnia magna is4.00mg/L and the EC50is29.75mg/L;the NOEC of5-methyl benzotriazole is1.00mg/L and the EC50is4.00mg/L.