ENVIRONMENTAL HEALTH INVESTIGATIONS BRANCH

Environmental exposures and health

Every day, we come into contact with chemicals from our environment. This includes chemicals or other harmful substances in the air, water, food, and commonly used products. This contact (or “exposure”) can take place in different ways and at different intensity and frequency. For example, the exposure can be intense and brief, or it can be low but continued over many months or years. The effects of exposure can also vary, from a sudden asthma attack to health problems that develop much later, like cancer. Health issues related to environmental exposures can include:

Respiratory disease, like asthma and emphysema
Cardiovascular disease, such as high blood pressure, strokes, and heart attacks
Developmental and neurological effects, including autism, learning disabilities, and Alzheimer’s disease
Hormonal and reproductive problems, like diabetes and infertility
Cancer, including lung, kidney, bladder, and liver cancers

The environment plays an important role in shaping our health

We know that chemical exposures can lead to illness or disease, but these exposures are just one piece of a complex interaction between many environmental factors and individual genetics. In addition, some groups of people are more vulnerable to the harmful effects of exposures because of their age, education, income, housing, activities, or other factors.

Children are more sensitive to chemical exposures because of their behaviors, developing bodies, and smaller size.
Lower-income communities are often in areas with multiple sources and higher levels of pollution, such as near highways, industrial facilities, and waste disposal sites.
Pregnancy is a very sensitive time period. Chemical exposures during pregnancy can affect the baby’s development, leading to birth defects or long-term developmental problems.
Older people may have weakened immune systems and are more prone to chronic disease.

Understanding the sources of environmental chemical exposures can help prevent negative health outcomes and promote overall well-being for everyone.

What the Environmental Health Investigations Branch does

The Environmental Health Investigations Branch (EHIB) works to prevent harmful environmental exposures. This includes:

Response to incidents and outbreaks involving chemicals and natural toxins
Monitoring and addressing the health impacts caused by climate change-related air pollution, extreme weather and disasters
Interventions to improve environmental conditions that cause or worsen asthma
Biomonitoring studies to better understand how people across California are exposed to chemicals
Health education and outreach materials on mold in the home, mercury in skin creams, and other harmful chemicals and products

Learn more about what we do:

EHIB staff have also investigated environmental exposures to tobacco smoke, lung injuries from vaping, and community health concerns like autism, cancer, obesity, and pre-term birth. Learn more about this work:

	E-cigarette, or Vaping, Associated Lung Injury (EVALI)
	Autism research
	Pregnancy and birth outcomes
	Superfund and hazardous waste site assessment

E-cigarette, or Vaping, Associated Lung Injury (EVALI)

Autism research

Pregnancy and birth outcomes

Superfund and hazardous waste site assessment

For more information

Read about how scientific research has identified links between environmental exposures and health outcomes on the US Environmental Protection Agency website.

What is environmental epidemiology?

Environmental epidemiology is the study of how the environment affects health. Environmental epidemiologists are scientists who work to understand the effect that environmental factors, like chemical exposures or climate change, have on people and identify which communities are most at risk.

Epidemiologists measure disease, or health conditions like asthma, and environmental exposures in a population to try to answer the following questions:

Do people exposed to a chemical have more disease than people who were not exposed?
Did people with the disease have a higher level of exposure than people without the disease?
How do environmental factors like air pollution or contaminated drinking water affect communities?
Are there consumer products or practices that contribute to environmental exposures?
Which people or communities are most affected?