Tuna for Lunch?
A Case Study Examining Mercury Bioaccumulation and Biomagnification
Department of Biological & Environmental Sciences
Georgia College & State University
This case examines mercury bioaccumulation and biomagnification within the context of the human health impacts of ingesting food (specifically, fish) contaminated with mercury. It was inspired by a 2009 USGS report on mercury in fish, sediment, and water from streams across the U.S. The case is intended to help students make the connection between an environmental contaminant (mercury, a neurotoxin) and the food they eat. Human activities have been increasing mercury concentrations globally, and coal-burning power plants are the most common source of mercury pollution, a fact many students are unaware of. The case has been used in an introductory level environmental science class (predominantly non-majors), a non-majors general biology class, and a sophomore level ecology class (majors).
- Explain why there are fish consumption advisories related to mercury.
- Explain how mercury enters and moves through the environment.
- Read, interpret, and apply scientific data presented in graphs and tables for this case study.
- Define biomagnification and explain how it leads to higher concentrations of toxins in animals that are higher up the food chain.
- Explore how biomagnification occurs in other systems and with other compounds (if students complete optional final activity).
KeywordsBiomagnification; bioaccumulation; mercury; neurotoxin; fish consumption; tuna; food chain; food web; trophic; coal-burning
Educational LevelHigh school, Undergraduate lower division, Undergraduate upper division
Subject HeadingsEnvironmental Science Ecology Biology (General) Limnology Toxicology Public Health
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