Smith and Student Researchers Test Effects of Toxins Commonly Found in Household Items
By Chris Macchi ’12
Dr. Sheryl Smith, Assistant Professor of Biology, is researching the effects of four synthetic toxins on fruit flies. The chemicals—Bisphenol A (BPA), Parabens, Phthalates, and Perfluorooctanoic Acid (PFOA)—are found commonly in American households.
Of these toxins, BPA may be the most well known. Used in the production of plastics, it made headlines recently when the Food and Drug Administration banned its use in baby bottles and cups. However, it is still used in many other containers. Similarly, PFOA is a toxin found in Teflon cookware. Labels warn consumers not to heat Teflon to high temperatures, as doing so can cause PFOA to seep into food.
To help investigate, Smith has employed the talents of six Arcadia students. Rising juniors Ashley Parker, AnnJosette Ramirez and Amber Weiner are joined in the research by three graduate students in Arcadia’s Forensic Science program, Kara Bennett, Kristin Johndreau, and Caroline Rachfalski. The team is using the Drosophila fruit fly, a commonly studied model organism, to test the effects of toxic-exposure during crucial development stages. Smith’s background is in cell and developmental biology, and she hopes that the team can use research techniques from these fields to bring greater understanding to the effects of toxic exposure.
“These are toxins with little-to-no literature on their effects on Drosophila. Their effects on mammals, specifically humans and mice, are well studied and known, but very specific. An overarching understanding of these effects on a model organism like Drosophila could help determine affected developmental pathways,” remarks Ramirez. She estimates that the team spends more than 20 hours in the lab each week.
By exposing fruit flies to toxic compounds at various periods during development, the team will be able to observe any effects potentially caused by the chemicals. These findings would be valuable pieces of information in the overarching understanding of toxic effects on vertebrates and invertebrates alike.
Two Boyer Hall labs have been outfitted with specialized photographic microscope equipment as well as the sophisticated incubators and temperature and humidity controllers which make this type of research possible. The group is able to stain a portion of a chromosome with a fluorescent dye allows for observation throughout development when observed with a UV light-emitting microscope.
“We’re able to actually see what is in the nucleus and what’s leaving the nucleus. We are very fortunate to have this equipment because it helps us to understand when things are activated and deactivated during the developmental process,” notes Rachfalski. “When you have something that’s mutated [as a result of toxic exposure], you can go back and look at the pictures to determine if development was altered. It allows us to take our results and get real-time data to support what changes we’re seeing in the flies.”
The research team will look for morphological defects such as smaller eyes, extra or abnormal veins in wings, and abnormal leg joints, among others. In addition, the team will be able to observe brain function and development by testing feeding, locomotion, lethality, virility and lifespan in the flies.
Per program requirements, all forensic science students must conduct research in order to graduate. The undergraduate research team, however, is made of students who are looking to gain more experience outside of their curricular requirements. And each of them anticipates attending graduate school in the future and continuing to pursue research thereafter.
“I’m so happy that Dr. Smith let all of us into her lab. It has opened a lot of career options that I had never thought of before this, so I’m really thankful for that,” says Weiner.
The experience has also opened Ramirez’s eyes to the enjoyment of conducting fulfilling research. “That’s the thing about science, it’s not a nine-to-five job. You go until the research is completed. I enjoy that aspect because it changes up—it’s not the same daily routine.”
Parker is similarly excited about the opportunities afforded to undergraduate students at Arcadia. “It’s really cool especially since we’ve only just finished our sophomore year—being able to do this [research] so early. There are so many other colleges that don’t start until their senior year, but we’re able to take on meaningful research much earlier.”