| | Category | MI | L21 | Effects of Ibuprofen on H. littoralis Feeding Reflex |
| | Abstract | Regulated water treatment and disposal makes water safe for drinking. |
| | However, because not all contaminants are regulated, water may not be |
| | purified relative to those contaminants. Common unregulated contaminants |
| | that can be found in a water supply include over-the-counter drugs. I |
| | investigate how an over-the-counter drug may affect a littoral ecosystem. I |
| | specifically examine the effects of ibuprofen on the feeding behavior of H. |
| | littoralis, a common freshwater species. I hypothesize that ibuprofen |
| | should interfere with this species’ ability to feed and that its feeding reflex |
| | would be noticeably slowed. Hydra rely on glutathione emitted by their |
| | prey to capture and consume their prey. Ibuprofen is a non-steroidal anti- |
| | inflammatory drug that reduces glutathione production. Ibuprofen may |
| | interfere with this link. |
| | |
| | My experiment focused on H. littoralis’ feeding reflex, which was |
| | measured by timing the duration between capture and ingestion of |
| | Artemia. Baseline feeding reflex of H. littoralis was recorded for a month. |
| | The group of hydra were then chronically exposed to specific |
| | concentrations of ibuprofen. Low levels of ibuprofen (20 mg/L) were not |
| | immediately detrimental to the H. littoralis, but gradually slowed its feeding |
| | reflex. Exposure to 40 mg/L of ibuprofen resulted in an immediate slowing |
| | of feeding reflex; by the third day of testing, H. littoralis stopped feeding. |
| | My results supports the hypothesis that ibuprofen interferes and slows |
| | the feeding reflex of H. littoralis. More slowing was correlated to |
| | increasing concentrations of ibuprofen. |
| | |
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| | |
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| | New York Times, 8 December 2009. |
| | |
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| | |
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| | |
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| | |
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| | |
| | Heckmann, L.-H., A. Callaghan, et al., 2007. “Chronic toxicity of ibuprofen |