Short‐term fish reproduction assays with methyl tertiary butyl ether with zebrafish and fathead minnow: Implications for evaluation of potential for endocrine activity

Abstract

The authors report on short-term fish reproduction assays in zebrafish and fathead minnow conducted to examine the potential for methyl tertiary butyl ether (MTBE) to cause effects on the endocrine system. Both studies were performed under good laboratory practice and in accordance with Organisation for Economic Co-operation and Development and US Environmental Protection Agency test guidelines. The results of the first study demonstrated that exposure to a high test concentration (147 mg/L) of MTBE impaired reproductive output of female zebrafish, evident by a reduction in fecundity. Based on the endpoints evaluated in the present study however, there was no supporting evidence to indicate that this effect was caused by disruption of or interaction with the endocrine system. In the second study, fathead minnows exposed to a wider but lower range of test concentrations showed no effects on any reproductive parameter of male or female fish, at the maximum recommended testing concentration of 100 mg/L (62 mg/L measured). The results of these 2 guideline studies indicate that MTBE does not interact with the hypothalamic-pituitary-gonadal axis of zebrafish or fathead minnow.

Development of anin vivoanti-androgenic activity detection assay using fenitrothion in Japanese medaka (Oryzias latipes)

“…In response, various test guidelines have been established by the Organization of Economic Cooperation and Development (OECD) to clarify the impact of EDCs on living organisms, including TG229 (OECD, ), TG230 (OECD, ) and TG234 (OECD, ). These guidelines utilize a variety of techniques to provide detailed information on the influence of chemical substances on living organisms (Ankley et al, ; Mihaich et al, ; Nakamura et al, ).…”