Testicular length by experimental group. As the perchlorate concentration increased, so did the length of testes. Mean testicular length (MTL) for two-year-old, wild-caught males was 7.8 mm (n = 8; SE = 0.24; top left). One-year-old control fish had an MTL of 6.0 mm (n = 7, SE = 0.54; top right). One-year-old fish in the 30 mg/L treatment had an MTL of 7.1 mm (n = 7, SE = 0.35; bottom left). One-year-old fish in the 60 mg/L teratment had an MTL of 9.3 mm (n = 7, SE = 0.21; bottom center), and one-year-old fish in the 100 mg/L treatment had an MTL of 10.6 mm (n = 6, SE = 0.22; bottom right). MSL = mean standard length; %SL = MTL/MSL).