Develop a 15-20 slide PowerPoint presentation on the environmental toxicology of one element. You should be able to research a lot of this material as you work through the homework assignments throughout the session. Select a contaminants only from the list below:
Arsenic (As)
Cadmium (Cd)
Chromium (Cr)
Copper (Cu)
Lead (Pb)
Mercury (Hg)
Nickel (Ni)
Selenium (Se)
Zinc (Zn)
Asbestos
An organic contaminant
This selection of contaminants offers a variety of environmental toxicological effects. Some act as nutrients for humans and other mammals at certain levels, but become toxic at higher levels, whereas others have no nutritional value. Some are highly toxic to aquatic organisms (fish and invertebrates), but less toxic to terrestrial organisms. The toxicity of some of these elements is higher when ingested as particulates as opposed to being consumed through drinking water. Some of these elements bioaccumulate in food webs, eventually making their way to humans. Collectively, these elements have a range of chemical behaviors, e.g., some are insoluble at low pH, whereas others are less soluble at high pH.
You may want to read ahead to the Week 6 (Metals) or Week 7 (Organic Contaminants) assignments depending upon your chosen topic for additional material.
Organization: The presentation should be organized in the style of a scientific presentation. As such, it should have the following sections:
Introduction: Defines the purpose of the presentation. It should also include the high points of the chemical nature of the element (atomic number, valence states, etc.). Also, report what the abundance of the element is in the Earth’s crust and in seawater.
Uses: Describe the uses of the selected element. In addition to course resources, you may also find useful information from the USGS Minerals Information Team (http://minerals.usgs.gov/minerals/index.html). Find details on each element under “Commodities.”
Environmental Guidelines: Summarize environmental guidelines for the elements in drinking water, soil (residential and industrial), stream sediment, and for acute and chronic toxicity to aquatic organisms. Note: there may not be guidelines for all elements in all media.
Pathways of Environmental Impact: Describe pathways that the element can affect humans and aquatic organisms. Are there key chemical transformations that affect the degree of impact? What are they?
Case Study: Describe at least one case study that highlights the environmental toxicology of your element to humans, aquatic organisms, or other wildlife. You CANNOT use any of the examples from class. You must find an example in the scientific literature. I suggest searching for articles through the APUS Library. Also, construct a figure or table to help summarize the main points of your case study.
Conclusion: Summarize your major findings in a slide or two.
References: You must cite all of your sources of information using APA format. Our library has guidance on APA formatting if you need a refresher.
