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EPA's Environmental Quality Index Supports Public Health


The air we breathe, the water we drink, the food we eat, and the buildings around us all play a part in our overall wellbeing. A look at the broader environmental context can help researchers better understand health outcomes and how they relate to cumulative environmental exposures.

EPA researchers created the Environmental Quality Index (EQI) to do just that. The index pulls data from five domains: air, water, land, built, and sociodemographic environments to provide a county-by-county snapshot of overall environmental quality across the entire U.S. This data can then be used to highlight associations between environmental quality and a given health concern.

“The EQI was created to assess how overall environmental conditions or a multi-pollutant domain like ‘air quality’ might be connected to adverse health outcomes,” explains Danelle Lobdell, Ph.D., an EPA epidemiologist leading the EQI research.

Interactions between the environment and public health are often complex. For example, people are exposed to lead via drinking water, contaminated soils, old household paint, and air pollution. By expanding research beyond singular routes of exposure and pollutants, the EQI helps provide a clearer picture of the relationship between the environment and our health.

For the Society for Epidemiologic Research conference in Seattle this June, Lobdell and colleagues are expecting to present a series of abstracts linking environmental quality to lung cancer survival, uncontrolled diabetes among the elderly, and cardiovascular hospitalizations. Their findings show a consistent relationship between poor air quality and poor health outcomes.

“We hope that these and other findings can improve understanding and provide motivation for action around health concerns,” explains Lobdell. “If, for example, a community is seeing increased rates of diabetes, then the results we are finding from the EQI and health analyses may provide insights to explore possible interventions by reducing environmental exposures to in turn reduce adverse health outcomes.”

Similarly, state public health agencies could use the EQI’s county level data to provide targeted support to address health concerns that are tied to environmental quality. Lobdell and colleagues recognize that the underlying EQI data has utility beyond just health outcomes. Ecologists, economists, and other researchers can use EQI data to address various questions relating to environmental quality. To support this scientific exploration, EPA has made the EQI and its many variables open and accessible to the public. You can learn more about the EQI and download data at:

The EQI team is keeping busy. In the past few years, two studies have been published linking health concerns (mortality and preterm birth) to environmental quality. The preterm birth study, which looked at how different environmental domains might interact with each other to affect preterm birth rates, was the first of its kind. Papers on cancer incidence, life expectancy, asthma, and a follow-up study on mortality are in the works. Lobdell and colleagues are also in the process of updating the EQI with more recent data, which will provide a look at environmental quality through time.

Lastly, the team is exploring the possibility of developing new census-tract level EQIs with local and regional coverage. This work could highlight health disparities tied to environmental conditions at a finer scale—helping prioritize support for those communities that need it most.

“We like the versatility of the EQI,” says Lobdell, “and we hope that it can increase our knowledge of cumulative exposures and ultimately help improve public health and wellbeing.” 

Learn More

EQI report and data download

EQI map layers

EPA Health Research

Sources and References

Grabich, S.C. et al. (2016). Additive Interaction between Heterogeneous Environmental Quality Domains (Air, Water, Land, Sociodemographic, and Built Environment) on Preterm BirthFrontiers in Public Health, 4. DOI: 10:3389/fpubh.2016.00232

Jian, Y. et al. (2016). The Associations between Environmental Quality and Mortality in the Contiguous United States, 2000-2005Environmental Health Perspectives. DOI: 10.1289/EHP119

Lobdell, D. et al. (2014). Environmental Quality Index - Overview Report. U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-14/305. Available at:

Messer, L.C., Jagai, J.S., Rappazzo, K.M., & Lobdell, D.T. (2014). Construction of an environmental quality index for public health researchEnvironmental Health, 13(1):39. DOI: 10.1186/1476-069X-13-39