Ingredients found in commonly used agricultural pesticides have been indicated to have negative effects on bacteria, particularly the beneficial kind that inhabit the human gastrointestinal tract. In this experiment, ingredients, 'Triadimefon and Glyphosate', present in two of the leading pesticides (Bayleton and Proturf products and Round-Up) were used to test the effect they had on the growth of the bacteria, Escherichia coli, found abundantly in our digestive system tracts. E. coli were plated on agar plates treated with various dilutions of the active ingredients, Triadimefon and Glyphosate, and growth observed over time. Results indicated that only Triadimefon caused a decrease in growth and colony forming ability of E. coli over time. The most effective dose appeared to be a 50% dilution of Triadimefon, a dose which was far less potent compared to the actual strength found in commercial products. Glyphosate known to be more toxic than Triadimefon had no adverse effect on the growth of E. coli in our experiments. While these results are preliminary and not conclusive, future studies could further analyze the specific effects these ingredients have on the bacteria, such as on their morphology, metabolism, various colony forming ability, and the rate of growth over time.