Assessing multiple endpoints of atrazine ingestion on gravid northern watersnakes (Nerodia sipedon) and their offspring

• Published in: Environmental toxicology Vol. 29; no. 9; pp. 1072 - 1082
• Main Authors: Neuman‐Lee, Lorin A, Gaines, Karen F, Baumgartner, Kyle A, Voorhees, Jaymie R, Novak, James M, Mullin, Stephen J
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons 01-09-2014; Blackwell Publishing Ltd; Wiley Subscription Services, Inc
• Subjects: amphibians; Animals; atrazine; Atrazine - toxicity; blood; Colubridae; Dose-Response Relationship, Drug; Endocrine disruptors; estradiol; Female; fetal death; fish; gestation period; Herbicides - toxicity; immune function; ingestion; Male; morphometry; mortality; mothers; Nerodia sipedon; progeny; reproduction; reptiles; sex ratio; sexual development; snakes; Water Pollutants, Chemical - toxicity; snakes; immune function; reptiles; sex ratio; reproduction
• ISSN: 1520-4081; 1522-7278
• DOI: 10.1002/tox.21837

Ecotoxicological studies that focus on a single endpoint might not accurately and completely represent the true ecological effects of a contaminant. Exposure to atrazine, a widely used herbicide, disrupts endocrine function and sexual development in amphibians, but studies involving live‐bearing reptiles are lacking. This study tracks several effects of atrazine ingestion from female Northern Watersnakes (Nerodia sipedon) to their offspring exposed in utero. Twenty‐five gravid N. sipedon were fed fish dosed with one of the four levels of atrazine (0, 2, 20, or 200 ppb) twice weekly for the entirety of their gestation period. Endpoints for the mothers included blood estradiol levels measured weekly and survival more than 3 months. Endpoints for the offspring included morphometrics, clutch sex ratio, stillbirth, and asymmetry of dorsal scales and jaw length. Through these multiple endpoints, we show that atrazine ingestion can disrupt estradiol production in mothers, increase the likelihood of mortality from infection, alter clutch sex ratio, cause a higher proportion of stillborn offspring, and affect scale symmetry. We emphasize the need for additional research involving other reptile species using multiple endpoints to determine the full range of impacts of contaminant exposure. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1072–1082, 2014.