Herbicides and insecticides are applied in agriculture sequentially or simultaneously to control broadleaf weeds, corn rootworm larvae, and other soil pests. Pesticide application creates the potential for movement to aquatic habitats via sediment or runoff, hence affects non-target aquatic organisms. Histopathological changes of gill tissues have been suggested as powerful and sensitive measures of stress and well-being offish. Atrazine and terbufos were found to cause tissue damage and mortality in fish. Literature concerning the effects of pesticide mixtures to fish and other animals at the histopathological level are rare. The present study focused on the impacts of atrazine and terbufos mixtures on fish gills.

Cyprinella lutrensis were obtained from the Platte River in Nebraska, USA and maintained in the laboratory at 23 °C and 30 °C. They were exposed to 0, 1μg terbufos + 10 μg atrazine L-1, 10 μg terbufos + 100 μg atrazine L-1, and 100 μg terbufos + 1000 μg atrazine L-1.