Abstract
As a result of the extensive use of atrazine in the 1960s, this herbicide has become the second most frequently used agrochemical in the United States. It effectively kills broad-leaf weeds and maintains commercial crops like corn, sorghum, and sugarcane. It can also be used to maintain residential lawns, sports fields, and playgrounds. However, due to its common use throughout the world, atrazine has been a frequent point of interest for agrochemical and environmental research. Atrazine has been shown to cause organ malformations, disrupt endocrine functions, and stunt growth in animals like birds, fish, rats, mice, rabbits, and amphibians. To further study atrazine’s detrimental impact on wildlife, this study examines caspase 3 as a measure of apoptosis, where programmed cell death is instigated by atrazine. This was done by exposing Xenopus laevis tadpoles to atrazine at concentrations of 0 μg/L, 21 μg/L, 200 μg/L, and 400 μg/L, and observing the fluorescence of the apoptotic marker caspase 3 as an indicator of the severity of apoptosis within the livers. Due to widespread mortality among all treatment groups, obtaining results that statistically showed a difference in severity of apoptosis was not achieved. Of the tadpole livers that were able to be sectioned, stained, and analyzed for caspase 3 fluorescence, there did not seem to be much of a difference in fluorescence across treatment groups. Additionally, images of the tadpole livers taken using a confocal microscope seem to coincide with the idea that there was not much of a difference in fluorescence.
This project also sampled different local water sources to examine the level of atrazine present. Samples were taken from four sites, three of which came from Michigan and one that came from Ohio. Due to the sampling technique for these water samples, statistics were not able to be done. However, after running an atrazine ELISA, the results suggest that there were lower amounts of atrazine prior to May, which is the typical time for atrazine application on farms, and high amounts of atrazine after May. The results also showed that atrazine levels were abundant in locations that did not apply atrazine in the year that we sampled.