Risk Assessment

Environmental Contaminants and Health: Communicating the Science to the Public (Course)

Content Cover Image

Source: U.S. Environmental Protection Agency.



Every day hundreds of educators, members of the public, and students turn to the World Wide Web with questions about the environment ranging from the effects of flame-retardants on beluga whales to the recycling of e-waste to ecosystem level impacts of climate change. Citizens and educators are looking for defensible, reliable, citeable science-based information on Earth’s environments and on their own impact in the world.

In a world of Google searches, blogs, and Really Simple Syndication (RSS) feeds, environmental scientists need to develop the skills necessary to communicate their findings to the public in an engaging and efficient, yet factual and accurate manner.

This course will provide students with a combined introduction to the basic concepts of environmental toxicology, with a focus on selected contaminants issues and the Encyclopedia of Earth (EoE), a free and comprehensive science-based encyclopedia designed for a general audience now available online at www.eoearth.org. The Encyclopedia is an excellent vehicle to communicate knowledge to the public in a manner that is effective, objective, non-partisan, easy-to-understand and free. Significantly, we will explore the “public face” of the EoE, and behind the scenes.

Throughout the semester students will be asked to apply what they are learning, by 1) investigating specific environmental contamination, and related human health topics; and 2) preparing articles suitable for publication within the Encyclopedia of Earth (including learning how to incorporate relevant images, charts and diagrams – to make the article more reader-friendly). Additionally, students will have a chance to practice their communication skills through participation in the online Earth Forum (http://www.earthportal.org/forum). This will provide them with an opportunity to ask questions of other Earth Forum members, practice writing by posting to the Forum and develop skills communicating with the public.

Table of Contents

Encyclopedia of Earth Basics


The goal of this course is to eventually publish on the EoE. The following topics will introduce you to the EoE, providing basic information on its audience and content style, and on publishing on the EoE.


As you will see there are a range of articles on the EoE. While they follow a basic format the writing style may vary depending on the author, source or topic. Some examples of different article types and styles are:

Writing on the EoE Wiki

  • EOE:Creating a New Article
  • EOE:How to Contribute

Toxicology Basics


The following sections will provide basic concepts that will help you ask the right questions about the impacts of contaminants on living systems, beginning with a historical perspective.

Dose makes the poison

One of the basic tenets of toxicology is that "The Dose Makes the Poison." Though this is a little more complicated, the point is: One cannot begin to evaluate the impacts of chemical contaminants without considering exposure and dose.

Interaction of contaminants with living systems

Once an organism is exposed to a toxicant, the effect of that substance will depend on what happens to it as it travels through the body. Consideration of absorption, distribution and excretion (ADE) are essential to understanding the potential for a chemical to cause harm.

Impacts on specific systems

Beyond the basics of ADE, a toxicologist considers how chemicals interact at the cellular level. For example, sometimes chemicals are detoxified by enzyme systems within certain cells, and sometimes, they are activated. Sometimes they need no activation, and can bind to receptors meant for other chemicals in the body.

  • Homeostasis

Combined contaminant exposures

Until most recently, most toxicologists studied the impact of single chemicals, an unrealistic scenario in many, particularly environmental cases. The study of chemical mixtures is a growing field of toxicology.

Toxicity Testing and Risk Assessment

When new chemicals are developed, and as various producers, users and regulators try to evaluate their potential impact on both humans and the environment, chemicals are tested, exposures are estimated and potential risk is evaluated.

Government agencies and legislation in the United States

There are a number of Federal agencies charged with protecting humans and the environment from potentially adverse impacts caused by chemical substances through various laws, policies and regulations (this is not a complete list please feel free to add.)



Environmental Justice and communities

The realization that many contaminated sites are disproportionately located near communities of color and near low-income communities led to a growing Environmental Justice movement and field of study. Additionally, researchers are beginning to realize that traditional and community knowledge about exposure, contaminantion, and environmental change provides valuable information to environmental and health assessment.

Reducing contaminant impacts



Chemical contamination worldwide

(In)famous sites of the twentieth century

Chemicals of note

Chemical contaminants of recent concern

Organochlorines: banned, but not gone

  • Dioxin

Air Pollutants






Monosson, E. (2013). Environmental Contaminants and Health: Communicating the Science to the Public (Course). Retrieved from http://www.eoearth.org/view/article/51cbedbb7896bb431f69380d