1. On the basis of the article, indicate one human activity that releases mercury into the environment. Describe how mercury is transported from that source and enters aquatic systems, often hundreds of miles away.
2. Describe two ways that the amount of mercury released into the environment from the source in part (1) could be reduced.
3. Explain why there are greater health risks associated with eating large predatory fish, such as tuna and sea bass, than from eating small non predatory fish.
4. Identify a toxic metal other than mercury that has a negative impact on human health and describe how it
is introduced into the environment. Describe an acute sublethal effect on humans that results from
exposure to this metal.