Chronic exposure to pentavalent arsenic of larval leopard frogs (Rana pipiens): bioaccumulation and reduced swimming performance.

Arsenic (As) is mainly released to the environment from anthropogenic sources, with inorganic pentavalent As (As [V]) predominant in surface water. In this study, Rana pipiens were exposed to As (V) in water at environmentally relevant concentrations (control, 10, 20, 150, 500, and 1,000 microg l(-1)) in a static-renewal system from post-hatch stage through metamorphosis for 113 days. There was no significant effect of As exposure on tadpole survival, growth, and percent metamorphosis. Maximum swimming speed was significantly slower in the As-treated groups compared with the control. During the period of tail resorption (Gosner stage 42-46), no significant differences in age at metamorphosis, survival, length of tail resorption period, snout-vent length of metamorphs, and sex ratio were found among treatments. Whole body As concentrations ranged from <0.6 to 5.31 mg kg(-1) dry mass, and were significantly higher in the 150, 500, and 1,000 microg l(-1) treatments than the control. Based on our data, larval tissue concentrations of As close to that reported in previous field studies were not associated with any significant effects except decreased tadpole swimming speed.