Bioassay of methyl tertiary-butyl ether (MTBE) toxicity on rainbow trout fish

Methyl tertiary-butyl ether (MTBE) has been widely used as a gasoline additive. Water resource contamination due to spillage and accidental leakage of gasoline during fuel transportation may cause an important threat to aquatic life. In this work, the bioassay of MTBE toxicity on rainbow trout was performed. MTBE solutions of 250, 500, 750, 1000, and 1250 mg L−1 were prepared in five aquariums and aerated for 96 h. LC50 values of each experiment were measured according to probit analysis. A mathematical relationship between time exposure and LC50 of MTBE for rainbow trout was developed. The relative toxicity of MTBE to rainbow trout and to other organisms was also reviewed. It was shown that the toxicity of MTBE does not change significantly in the time exposure between 24 and 72 h varying from 878 to 831 mg L−1, respectively. After 72 h of rainbow trout exposure to MTBE, LC50 value gradually decreased and reached 773 mg L−1 in 96 h of contact time. In conclusion, the result of this work showed that the toxicity of MTBE to rainbow trout was relatively low.