Rats and guinea pigs fed 100 mg/kg daily for 6 months had decreased weight gain, increased white blood cell counts, decreased blood cholinesterase activity and deterioration and inflammation of the stomach. In a 28-day study, oral doses of 2,500 mg/kg/day to rats resulted in stomach ulcers, damage to the small intestine, and death

MCF-7 and MDA-MB-231 cells were seeded into 96-well plates either in maintenance media (MCF-7 and MDA-MB-231) or in reduced media (MCF-7). Twenty-four hours after plating, the media were replaced with maintenance (MCF-7 and MDA-MB-231) or reduced (MCF-7) media containing atrazine, simazine, or cyanazine at 0.1-, 1-, and 10-fold the EPA safe levels or DMSO control. Atrazine was added at 0.3, 3.0, or 30 ppb (𝜇g/L; 0.64–64 𝜇M), cyanazine was added at 0.1, 1.0, or 10 ppb (0.17–17 𝜇M), and simazine was added at 0.4, 4.0, or 40 ppb (0.92–92 𝜇M). After twenty-four hours, 3 𝜇g resazurin was added and allowed to incubate for three hours prior to reading absorbance at 570 and 595nm on iMark Microplate Absorbance Reader (Bio-Rad, Hercules, CA).We performed univariate analysis of variance (ANOVA) using SPSS