The herbicide atrazine (2-chloro-4-ethylamine-6-isopropyl-ainines-triazinc) is widely used for selective control of broadleaf and grassy weeds in corn and sorghum in addition to other crops (Geigy Agricultural Chemicals 1971). It is formulated and available as an SO percent water dispersible powder or a 4 percent granular product. Atrazine acts atî an inhibitor of photosynthesis and persists in the soil from 7 to 18 months depending upon soil properties, influence of weather, and the soil environment (Burnside et al. 1971, LeBaron 1970, Mullison 1970, Sheets 1970, Sheets and Shaw 1963).

Herbicides are generally lover in toxicity than many other pesticides. Of 89 pesticides tested by Heata et al. (1972), toxicity of atrazine was not great enough to warrant a toxic rank number. Devany (1967) stated that atrazine when used in accordance with recommended procedure, was not hazardous to fish or wildlife. The LÜ50 for a single oral dose of atrazine (AAtrex, 80 percent atrazine) for female mallard ducks (Anas plntyrhynchos) 6 months of age is > 2000 mg/kg (Tucker and Crabtree 1970). The. LC50's of technical grade atrazine in 5-day diets for 2-week-old birds are: (1) bobwhite quail (Colinus virginianus), >5000 ppm, (2) Japanese quail (Coturnix ce turrax japónica),>5000 pom with 7 percent mortality at the 5000 ppr.i level, (3) ring-necked pheasant 5000 ppm, and (4) mallard,>5000 ppn with 30 percent mortality at the 5000 ppm level (Heath et al. 1972). Palmer and Radelefi (1969) found that chickens receiving 10 doses of 50 mg/kg showed significant reduction in weight gained arri lack or loss of appetite.