Discipline: Ecology Environmental and Earth Sciences
Tyler Plum - West Virginia University
Co-Author(s): Jhamyllia Rice and Eric May, University of Maryland Eastern Shore, Princess Anne, MD
Many studies have found that organic pesticides, especially chlorinated hydrocarbons, are absorbed by organisms through bioaccumulation in most marine ecosystems, usually in food chain bioaccumulation and magnification. Sharks are one example of a commercially and recreationally valuable organism that could be affected by these contaminants, as they are at a greater threat from bio accumulation, being top level predators. It is therefore important to understand how these chlorinated hydrocarbons are absorbed from their diet, and how they move as digestion occurs. To test this, we sampled a number of smooth dogfish, Mustelus canis, and attempted to correlate the results of gut content position analyses at the time of death to chlorinated hydrocarbon concentrations in the liver. Chlorinated hydrocarbon concentrations were expected to spike at different points in digestion, and by comparing the results of multiple shark diet analyses, which were sacrificed at varying stages of digestion, to their liver concentrations, it was assumed a conceptual map of how these chemicals are absorbed during digestion could be created. In reality, no chlorinated hydrocarbons were found in any of the liver samples, a highly unexpected event. It is assumed that either 1) chlorinated hydrocarbons are absorbed at a continuous rate from the liver into the bodily tissues (i.e. muscle), leaving them virtually absent from the liver, or 2) that the sharks are not absorbing chlorinated hydrocarbons into their body or liver because they are excreted as waste at a rate that does not allow adequate time for absorption. Future research into how the chlorinated hydrocarbons react with the sharks’ biochemistry.
Funder Acknowledgement(s): We would like to thank the National Science Foundation for the support and funding for this research.
Faculty Advisor: Eric May,