Environmental health is a branch of science that tries to understand how interactions with the environment can result in illnesses or death. By understanding this, scientists can look for ways to prevent or control illness and improve health and quality of life.
Disease is caused by a complex interaction between genetic and environmental factors. These factors can include chemical pollution, nutrition, lifestyle, infectious agents, and stress. This website focuses on the impact of environmental factors from chemical pollution and hazardous waste sites on human health.
How does a substance get into the human body? A hazardous substance may leave its source and travel through air, water, or soil to a place where humans may come into contact with it by eating, drinking, breathing or touching it. This is known as a pathway of exposure, or 'exposure pathway.' When a person comes into contact with a hazardous substance, the exposure pathway is complete. There are many different ways that people may be exposed to hazardous substances. The information provided here describes a few of them.
|In environmental health,
scientists try to understand
if an exposure is happening,
and if health outcomes could
be related to an exposure.
Not all exposure pathways are listed in the graphic above. Below is fuller description of exposure pathways.
|outdoor air||contaminants released into the air are breathed in by people and can be absorbed through the skin|
|drinking water||contaminants released into the soil, surface water and groundwater can move into a drinking water source, such as a private well. People can then be exposed through drinking, bathing and cooking with water from the private well.|
|food chain||contaminants released into soil where plants are grown, or into a lake where fish live, or into the groundwater which is used to irrigate the plants. People can then be exposed when eating the fish or the plants or an animal that fed on the plant and produces an edible product (such as eggs or milk).|
|soil||contaminants are released into the soil where people may play or garden. After touching the soil, people may touch their food or mouth and thus accidentally ingesting/eating the contaminant. Some contaminants can be absorbed by the skin and carried into the body. Contaminants in soil are sometimes tracked into the home in shoes or clothing - where others might incidentally touch, breathe, or ingest them.|
|breathing indoor air after vapor intrusion||vapor intrusion is the migration of volatile chemicals from the contaminated groundwater or soil into overlying buildings where people breathe the air.|