Discipline: Biological Sciences
Subcategory: Microbiology/Immunology/Virology
Veronica N. Alston - Tuskegee University
Co-Author(s): Aiesha Ethridge, Richard Whittington, Michael Curry, and Raymond Shange, Tuskegee University, Tuskegee, AL
Global pollution rates have resulted in the ocean containing an estimated 5.25 trillion pieces of plastic, with 8 million tons of plastic is being added annually. It is important to monitor pollution levels in our global waterways to maintain a value food resource for human consumption. In 2008, the Aquaculture Industry was responsible for supplying 50 % of the seafood consumed by the global population, worth $98.5 billion. The presence of plastic pollution threatens the Aquaculture Industry due to the negative impact on aquatic species and human health. There have been studies linking plastic pollution to tumor and liver problems in fish. Plastic exposure can result in carcinogenic compounds leeching into the tissues of aquatic organisms and enhancing the risk for various forms of cancer related to plastic exposure in humans that ingest contaminated seafood. If marine life ingests plastic pollution the chemicals that are within the plastic will seep out of the plastic and into the digestive track of the fish as well as the flesh of the fish. If humans were to eat the contaminated fish, we could be exposing our bodies to carcinogenic chemicals and toxins. Plastics can slowly be degraded by the microbes that exists in the gastrointestinal track and by the salt water. Research is needed to study the relationship between plastics, the rate of plastic degradation in the digestive system of fish, and the presence of carcinogenic compounds in the tissue of fish. A field study was performed where approximately 500 fish were collected to compare the presence of plastic and intestinal microbes in farm-raised catfish and gulf coast catfish. Current studies will focus on the mechanism involved in the degradation rate of polyethylene, polylactic acid, acrylonitrile butadiene styrene (ABS) when exposed to several bacteria associated with the gastrointestinal track. Plastic pellets will be inoculated with bacteria and monitored for a 4-week period to examine the interactions between the microbes and the plastic. The plastic pellets were also tested with salt water and fresh water. We monitored the degradation of the plastic to examine the interactions between the microbes and the plastic as well as the salt water and plastic. A final study will be performed to examine the effect of direct exposure of plastics to fish. Over a 4-week period, catfish will be feed variation of feed and plastic. Data on water quality, weight, growth rate, and the presence of plastics/carcinogenic compounds in fish tissue will be collected. With more time we can examine the health of the catfish from a juvenile stage to adult hood and to examine the effects the toxins could have on the quality of breeding the next generation.
Funder Acknowledgement(s): HHMI
Faculty Advisor: Richard Whittington, whittingtonr@mytu.tuskegee.edu
Role: 1.) Collect the fish tested the plastic with the salt water, fresh water, and the microbes; 2.) The feed study.