SPERM TALES: HOW THE MOST WIDELY USED HERBICIDE AFFECTS REPRODUCTION IN MALE FISH

1. SPERM TALES: HOW THE MOST WIDELY USED HERBICIDE AFFECTS REPRODUCTION IN MALE FISH Jeffrey S. Hatzel, Hannah J. Braun, Matthew N. Arnold (Susan Allen-Gil) Department of Environmental Studies & Sciences, Ithaca College With roughly 30,000 tons applied annually (Hase et al 2007), atrazine is the most widely used herbicide in the United States. It is most commonly used on corn and sorghum crops (Mo. Dept. Natural Resources 2007). The European Union banned atrazine use due to its suspected potential to act as an endocrine disruptor and carcinogen (Ackerman 2007). Hase et al (2007) found that atrazine significantly reduced the percentage of sperm with progressive motility (moving in a straight line) in a concentration-dependent manner in the fathead minnow. Tillitt et al (2010) found similar results in the fathead minnow: gonadal abnormalities and reduced spawning events occurred in test groups exposed to atrazine. This study assessed the effects of atrazine on sperm morphology in the fathead minnow (Pimephales promelas). Sperm from males exposed to 5µg/L (n=6), the average concentration of atrazine found in surface water in New York State (Eckhardt et al 1999), for 14 days were compared to those in aquaria without atrazine (control, n=2). Sperm were analyzed for average head radiusand tail length. The tail length was signi- ficantly reduced in atrazine exposed fish (mean tail length of control 21.74µm ± 2.90µm, compared to exposed 16.94µm ± 2.74µm, p<0.05). Reduced tail length may negatively affect movement speed and direction of sperm.