When the first edition of Ecotoxicology of Amphibians and Reptiles was published in 2000, I reviewed the state of the literature from 1972 through 1998 (Sparling et al. 2000). That review covered 11 271 contaminant citations listed in Wildlife Review and Sports Fisheries Abstracts published by the US Fish and Wildlife Service. Among its findings, only 2.7% of the cited papers were on amphibians and 1.4% on reptiles. This equated to an average annual rate of 11.5 citations for amphibians and 6 for reptiles, although the distribution of citations was not homogeneous through the years. In contrast, 61.8%, or 280, contaminant citations per year were on fish. Among the amphibian citations, most focused on effects, 23% dealt with metals, 22% with acid precipitation, and 19% with nonchlorinated pesticides. The remaining 38% covered all of the other contaminants of interest at that time. Almost all of the citations on reptiles dealt exclusively with residues, and turtles (Chelonia) were overrepresented compared to the percent of reptilian species comprised by this order. The most important categories of contaminants included metals (24%), organochlorine pesticides (23%), and polychlorinated biphenyls (PCBs) (19%), all persistent pollutants.
