This study aims to (1) establish fish embryo chronic toxicity testing method；(2) establish toxicity identification evaluation procedure for high-tech industry effluent; (3) establish acute toxicity testing method for seawater.
Zebrafish, a popular tropical fish, possesses the advantages of short generation cycle, transparent egg shell, and high fertility. The juvenile is capable of reproduction after 120 days, leading to its wide use in toxicology study. We therefore chose Zebrafish as the model organism to establish chronic toxicity testing method. According to OECD method, we used 3,4 DCA and NaCl as reference toxicants and performed five times of chronic toxicity testing. The results show that Zebrafish embryo hatching rate, survival rate, heartbeat rate, and larval locomotor behavior are appropriate and sensitive as indicator for chronic toxicity test.
We established toxicity identification evaluation first and collected background information of manufacturing process and raw material used in high-tech industry. Based on the effluent monitored data, we identify copper sulfate, zinc sulfate, cadmium sulfate, gallium sulfate, indium nitrate, copper nitrate, cadmium nitrate, lead nitrate, and molybdenum trioxide as major toxicants in waste effluent. We used the aforementioned metal compounds as reference toxicant for toxicity testing of Daphnia magna, Pseudorasbora parva, and Zebrafish embryo. The results demonstrate that copper nitrate exhibited the highest toxicity. Both EDTA and cation exchange resins were evaluated as physico-chemical treatment in toxicity identification evaluation. The treatment efficiency of EDTA better and can meet the heavy metal characteristic of the high-tech industry effluent in Taiwan.
We preliminarily selected black seabream, Vannamei shrimp, Japanese medaka, and Taiwan medaka as candidate organism for acute toxicity testing method for seawater. According to EPA 2002 method and OSPAR 2006 method, we used cadmium sulfate and 3,5-dichlorophenol as reference toxicants. Finally, we used Japan medaka to establish domestic acute toxicity testing method for seawater.