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Science Advisor Programs

What types of human subjects research does EPA conduct and fund?

EPA conducts and funds a wide variety of human subjects research (HSR). Some examples of HSR at the EPA include fish consumption surveys, surveys on household practices or demographics, analysis of biological specimens, use of focus groups, controlled exposure studies and epidemiology studies.

Each of the study examples listed above serves a particular research need. For example, epidemiology studies enable researchers to learn more about environmental exposure that individuals encounter in everyday life. The National Epidemiological and Environmental Assessment of Recreational (NEEAR) water study is an example of an epidemiological study in which researchers investigated the human health effects associated with exposure to pollutants at recreational swimming sites. The goal of the study was to evaluate whether real-time water quality measurement techniques could be utilized to alert and prevent beachgoers from entering the water and possibly becoming ill if high levels of pollutants were being recorded. Results are intended to enable EPA's Office of Water to develop new state and federal guidance for water quality indicators of fecal contamination.

Another category of human subjects research that is often utilized in EPA studies is survey research. Any time researchers administer a survey, questionnaire, or other data collection instrument, they are interacting with human subjects.  If the data that researchers collect from subjects is about the subjects themselves, then the research meets the definition of human subjects research at 40 CFR Part 26. Even if a survey is completely anonymous, if people are providing information about themselves, it constitutes human subjects research! For example, if a researcher passes out anonymous surveys on a beach and asks about the individual's frequency of swimming at the beach or opinion about the cleanliness of the water, it still qualifies as human subjects research since the individual is answering questions about themselves. Often times, survey research is just one component of a larger study but it is still subject to HSR review. 

A final example of human subjects research at the EPA is controlled exposure research. EPA conducts controlled exposure studies in healthy individuals or those with mild medical conditions, for example mild asthma who are at minimal risk to the effects of particulate matter (PM), to understand the biological pathways by which air pollution particles exert their effects. Scientists can extrapolate the results from these studies to understand how PM may lead to illness or death in at-risk populations such as individuals with heart or severe lung disease. These studies help EPA fulfill its legal requirements to establish a National Ambient Air Quality Standard that protects Americans from the harmful effects of PM. 

Why does EPA conduct controlled exposure studies? 

We can (and do) learn much from research in test tubes or using animal or computer models. But these are not all equally good predictors of ways the human body is affected by common pollutants. Even epidemiological studies rely heavily on statistical inferences and assumptions, and there are some things researchers can only learn by interacting directly with people, controlling variables and methods to allow firm conclusions to be drawn. 

Over the years, scientific research with human subjects has provided much valuable information to help characterize and control risks to public health. This type of research enables investigators to test the effectiveness of insect repellants, measure the rates and pathways of human processing of environmental chemicals, measure occupational exposure of workers to chemicals, and measure the effects of a substance on exposed human subjects. EPA’s program offices use results from these studies to support decisions and set regulations such as National Ambient Air Quality Standards, water quality criteria and drinking water standards, cleanup levels, and pesticide registration.

Other types of human subjects research are intended to collect information about an individual’s behavior, opinions, and/ or characteristics in order to contribute to generalizable knowledge. Examples include surveys, focus groups, and interviews.

The focus of controlled exposure research is to gain a better understanding of changes in the body that are associated with exposure to the substance that is being studied. By understanding exactly how commonly-occurring pollutants affect various people, the EPA can make appropriate recommendations to Congress and other State and Local governments about enacting laws that protect us and our environment.

Controlled exposure research also contributes to testing the effectiveness of insect repellents, measuring the rates and pathways of human processing of environmental chemicals, measuring occupational exposure of workers to chemicals, and measuring the effects of a substance on exposed human subjects. These studies advance the EPA’s understanding of the links between the environment and human health so that the Agency is able to carry out its mission of protecting human health. 

What controlled exposure studies are currently enrolling?

Clinical Studies in Environmental HealthEXIT