Neighborhood Health: Pollutant Exposures & Chronic Disease Risk

The neighborhoods in which people live play a major role in their health and well-being. Many people in the United States and across the globe live in communities that have health and safety risks, such as high rates of violence, inadequate access to health care or nutritious foods, and unsafe air and water due to pollutants. In the US, people with low incomes and communities of color are more likely to live in neighborhoods with these risks.^1,2 Specific to toxicant exposures, approximately 73 million people in the US live within three miles of a Superfund site,³ which is a polluted location that requires a long-term response to clean up contamination. Reporting from the Environmental Protection Agency states that residents living near the sites are disproportionately communities of color or those with a lower socioeconomic status.³ In addition, according to 2010 data, more than eight million people in the US live within 1.8 miles of commercial hazardous waste facilities.⁴

Multiple neighborhoods are situated close to major roadways, industrial and agricultural operations, and other potential pollutant sources that may influence an individual’s daily toxicant exposure level."

According to the American Lung Association’s 2024 State of the Air report, nearly 39% of people in the US live in places with unhealthy levels of air pollution, and people of color are 2.3 times more likely than white people to live in a county with a failing grade for ozone air pollution, short-term particle pollution, or year-round particle pollution.⁵ 

Studies continue to illustrate environmental exposure inequities, with certain communities and locations disproportionately exposed to toxic chemicals that increase chronic disease risk and development.^6-9 How does awareness of a patient’s physical environment and their neighborhood’s health help to inform a personalized therapeutic plan or treatment approach? 

Residential Location, Exposure to Pollutants, and Disease Risk

Assessing the “health” of a patient’s neighborhood may indicate their potential level of exposure to toxic chemicals and provide vital health story information to help determine root causes of chronic conditions. Observational studies have suggested that people who live close to brownfield sites (i.e., former industrial or commercial sites that may be polluted) or close to major roadways may have higher amounts of environmental toxicants in their body.¹⁰ The studies also suggest that people who live close to petrochemical industrial complexes and other industrial pollutant sources, agricultural operations, or areas with increased highway and traffic density may be at increased risk for developing certain cancers such as lung,¹¹ breast,¹² blood,¹³ and colorectal cancer¹⁴ as well as other chronic conditions such as respiratory,¹⁵ metabolic,¹⁶ cardiovascular,¹⁷ autoimmune,¹⁸ and neurological diseases¹⁹ and chronic multimorbidity.²⁰

A 2022 observational study with data from 774 adult participants from the Detroit Neighborhood Health Study investigated the effect of residential proximity to brownfields, highways, and traffic on blood serum levels of heavy metals such as lead, mercury, manganese, and copper.¹⁰ Researchers found that closer proximity to brownfield sites was associated with increased serum lead and mercury, while living closer to increased highway and traffic density was positively associated with serum lead and manganese.¹⁰

In 2021, an umbrella review of meta-analyses evaluated the associations between environmental risk factors and health outcomes and included the impacts of residential location and surroundings on disease development.¹⁶ Among the reported results, living near major roadways or locations with increased traffic exposure was a suggested risk factor for type 2 diabetes in adults and leukemia in children.¹⁶ Further, residential proximity to petrochemical industrial complexes (PICs) was associated with risk of leukemia development, with one 2020 meta-analysis finding that within a maximum distance of eight kilometers, residential exposure to PICs increased leukemia risk by 36% (pooled RR=1.36, 95% CI=1.14-1.62) compared to controls, regardless of sex and age.¹³ 

Recent observational studies have connected other residential locations with potential pollutant exposures and health outcome inequities. Data from the 2008-2013 Survey of the Health of Wisconsin suggested that compared to those living farther away, adults living within 35 kilometers of a coal-fired power plant may have an increased odds of worse pulmonary function as measured by an expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) ratio below 80%.²¹ The analysis also found that while Black individuals were 4.8% of the total sample population, they accounted for 13.3% of those living within the 35-kilometer distance.²¹ In addition, the study found that while Hispanic populations were 2.8% of the sample population, they accounted for 4.8% of those living within 35 kilometers of a power plant.²¹

Clinical Applications

Potential exposure to pollutants based on residential location is a vital component to consider when receiving a patient’s health story and reflecting timeline details that may influence disease development or progression. In addition, considering the impact of a patient’s physical environment and possible toxicant exposure levels may help focus or prioritize therapeutic treatments. 

A 2022 Gallup poll publication found that US adults have substantial worries about specific environmental issues such as exposure to contaminated drinking water and air pollution.²² Yet even if patients do not immediately recognize their daily surroundings as contributors to their health, collaborative patient-practitioner conversations may help to identify potential pollutant sources and to understand a patient’s toxic exposure level and their individual circumstances. IFM offers clinical tools that help screen and assess a patient’s exposure to toxicants. Public online tools such as the EPA’s Toxic Release Inventory Fact Sheet²³ may help to correlate a patient’s neighborhood to pollution and exposure levels.

Assessment of a patient’s total toxic load and recognizing ongoing exposures are essential pieces of practical therapeutic treatments that prioritize reducing toxicant exposures as much as possible while implementing lifestyle modifications to enhance biotransformation pathways and elimination processes. Optimizing a patient’s nutritional status, ensuring adequate fiber and water intake, eating more phytonutrient-dense and diverse foods, and supporting liver function through targeted, nutrient-dense diets are all dietary treatment approaches within the functional medicine model that may be implemented to help support the elimination of toxic compounds and alleviate toxic burden. Supplements such as probiotics have also been highlighted in human and animal studies for their potential protective effect against the toxicity of some pollutants such as heavy metals.^24-26

At IFM’s Environmental Health Advanced Practice Module (APM), learn more about how your patient’s physical environment and toxicant exposure levels may impact their health outcomes and what lifestyle-based tools may benefit their wellness path.