Exploring Environmental Health Science
The EHS System
The basic process of Environmental Health Science is simple. It starts with the fact that anything that affects health has to come from somewhere. So the source of the agent has to be identified. Sources can be either natural or man-made.
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The source emits an agent that we can describe as being chemical (like car exhaust), physical (like noise or radiation), or biological (germs).
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The agent then enters what we call an environmental media, a general description of what kind of place the agent will go. It could be into the air, water, soil, or even onto surfaces, like tabletops or even someone's hands.
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A very important consideration in EHS is that once in the environment, the agents move around and they may even change. We call this distribution .
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After the agent has been transported it reaches the person or people that it might affect. We call these receptors . The process of an agent into a receptor is called exposure.
Exposure can be by breathing, eating, drinking, or even through their skin. It is important to know how much, how long, and how often exposures occur. The health effects of an agent depend on these factors.
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EHS doesn't end there though! Other things take place in communities when people are affected by environmental agents. Even the possibility or concern about what may happen is important to communities and groups. Often people feel angry or afraid. Group responses can prompt them to action.
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Once people begin to feel strongly about an environmental health issue, they can then influence societal processes to try to change things. Societal processes are actions such as lawsuits, law making, protests, product boycotts and other political action.
SOURCE . AGENT . MEDIA . DISTRIBUTION . RECEPTORS . SOCIETAL PROCESSES . GROUP RESPONSES . ENVIRONMENTAL CONTROLS
Ultimately, the goal of these societal processes is to somehow control the release of the agent from the source. By controlling (reducing or eliminating) source emissions, the overall health of the community and environment will be improved. Controls can be the application of cleaner processes, better pollution removal devices, stricter regulations, changes in management practices, and even educational efforts.
