Styrofoam chemicals on daphnia
Georgia Cooperwilliams, Amrita Dhillon
Floor Location : J 204 H
Styrofoam, listed by the NRC (National Research Council) as “reasonably anticipated to be a human carcinogen,” is frequently used all over the world. Thanks to companies like Dunkin’ Donuts there are 25 billion styrofoam cups thrown away every year in America (“Get the Facts”) and in Vancouver, there are 2.5 million disposable cups being thrown away every week, many of which are styrofoam (Hernandez). The general public is being exposed to styrene, a chemical in styrofoam that has been proven to cause cancer (Cross), including lymphoma and leukemia, as well as other life-changing problems like hearing loss and impaired learning (“Toxic Substances”). We studied the effects of styrofoam on daphnia due to the fact that daphnia, little invertebrate, can be used to replicate the human cell and therefore the results that we got from them would be pretty similar to those that we would get from a human body. Because of prior research done in this area, including multiple studies like one done where they concluded that people who worked with styrofoam were diagnosed at a younger age than the median (Bertke and Ruder), we hypothesized that the styrene would have an effect on the daphnia, rendering their lifespan shorter in response to exposure to different types of styrofoam. In particular, we thought that the styrofoam take-out boxes, the thickest of the three would have the most effect on how short the lifespan of the daphnia was, while the plates would come second and the cups, third. This is due to the fact that the styrofoam takeout boxes were the thickest and densest of the three, meaning they would be able to contain more styrene than the other two, causing quicker deaths. We used different types of styrofoam as our independent variable and, used the water that the daphnia had come in as our control. Our first step was to soak the different styrofoam products, 3 plates, 3 cups, and 3 takeout boxes, in water that was at 100 degrees Celsius, for 21 minutes. We then took 5 ml water from each container and tested it in the UV Spectrophotometer in order to see whether it could detect any chemicals that had leached into the water from the styrofoam. We took this step because the UV Spectrophotometer is very accurate and we could use its results to predict what would happen with the daphnia. We then took 15 ml of the styrofoam water and 15 ml of the water that the daphnia originally came in, and exposed the daphnia to this water mix. We put 10 daphnias in each of the three Petri dishes plus the control. We monitored the daphnia lifespan for six days to measure daphnia survival. The data will be presented at the Greater Vancouver Regional Science Fair.