Jeffries, M.K., Stultz, A.E., Smith, A.W., Rawlings, J.M., Belanger, S.E., Oris, J.T. (2014) Alternative methods for toxicity assessments in fish: Comparison of the fish embryo toxicity and the larval growth and survival tests in zebrafish and fathead minnows. Environmental toxicology and chemistry. 33(11):2584-94.
An increased demand for chemical toxicity evaluations has resulted in the need for alternative testing strategies that address animal welfare concerns. The fish embryo toxicity (FET) test developed for zebrafish (Danio rerio) is one such alternative and the application of the FET test to other species such as the fathead minnow (Pimephales promelas) has been proposed. Here, the performance of the FET tests and larval growth and survival tests (LGS, a standard toxicity testing method) in zebrafish and fathead minnows was evaluated. This required that: 1) testing methods for the fathead minnow FET and zebrafish LGS tests be harmonized with existing test methods and 2) the performance of these testing strategies be evaluated by comparing the median lethal concentrations (LC50s) of two reference toxicants, 3,4-dicholoraniline (DCA) and ammonia, obtained via each of the test types. Results showed that procedures for the zebrafish FET can be adapted and applied to the fathead minnow. Differences in test sensitivity were observed for DCA, but not ammonia; therefore, conclusions regarding which test types offer the least and/or most sensitivity could not be made. Overall, these results show that the fathead minnow FET test has potential as an alternative toxicity testing strategy and further analysis with other toxicants is warranted in an effort to better characterize the sensitivity and feasibility of this testing strategy.