Evaluating the Role of Fish as Surrogates for Amphibians in Pesticide Ecological Risk Assessment

Abstract

1 0 1 1 1 2 2 ABSTRACT 1 3 Ecological risk of chemicals to aquatic-phase amphibians has historically been evaluated 1 4 by comparing estimated environmental concentrations in surface water to surrogate 1 5 toxicity data from standard fish species. Despite their obvious similarities, there are 1 6biological disparities among fish and amphibians that could affect their exposure and 1 7 response to chemicals. Given the alarming decline in amphibians in which anthropogenic 1 8 pollutants play at least some role, evaluating the potential risk of chemicals to amphibians 1 9 is becoming increasingly important. Here, we evaluate relative sensitivity of fish and 2 0 larval aquatic-phase amphibians to 45 different pesticides using existing data for three 2 1 standardized toxicity tests: (1) amphibian metamorphosis assay (AMA) with the African 2 2 clawed frog (Xenopus laevis); (2) fish short-term reproductive assay (FSTRA) with 2 3 freshwater fathead minnow (Pimephales promelas); (3) fish early life stage test with P. 2 4 promelas or rainbow trout (Oncorhynchus mykiss). The advantage of this dataset over 2 5previous work is that these studies show high consistency in exposure method and 2 6 exposure concentration validation, study duration, test species, endpoints measured, and 2 7 number of concentrations tested. We found very strong positive relationships between 2 8 fish and tadpole lowest adverse effect concentrations (LOAEC) for survival (r 2 =0.85, 2 9 slope=0.97), body weight (r 2 =0.77, slope=0.98), and length (r 2 =0.77, slope=0.92) with 3 0 only one out of 45 chemicals exhibiting 100-folder greater sensitivity in frogs relative to 3 1 fish. While these results suggest comparable toxicity for pesticides between these two 3 2 groups of vertebrates, testing with a greater diversity of amphibians will help determine 3 3 the generalizability of these results across all amphibians. 3 4 3 5 3

Recent Progress and Prospects in Catalytic Water Treatment

“…), nematicide, molluscicide, piscicide, avicide, rodenticide, bactericide, insect repellent, animal repellent, antimicrobial, and disinfectants for preventing the spread of bacteria, and compounds used to control mice and rats. Ecological risk of such chemicals to aquatic-phase amphibians and fish is high and directly related to their high diversity [497][498] . The pesticide biodegradation can be carried out under aerobic or anaerobic conditions 488 .…”