More than half of US parks are within 2 miles of toxic sites, researchers find

Public parks and toxic waste sites may seem like separate parts of the landscape, but a new nationwide review suggests they are often far more intertwined than people realize.

In some cases, there is virtually no separation at all, with thousands of public parks occupying land that overlaps with or sits directly on sites contaminated by pollution.

What's happening?

According to Gizmodo, researchers from the University of Michigan cross-referenced data from the Environmental Protection Agency noting major pollution sites against 151,366 public parks, hiking trails, and multi-use school playgrounds. The data showed 26,886 parks — nearly 18% of all public parks included in the study — are located less than two miles from an EPA-designated Superfund site, which are areas of land that are significantly polluted and require cleanup.

The study, published in the journal Scientific Reports, also identified more than 2,000 parks that physically overlap with a Superfund site.

Gizmodo noted that the researchers looked beyond Superfund locations as well, examining sites in the EPA's Toxics Release Inventory. That broader category includes industrial and federal facilities that are required to report their handling of certain hazardous chemicals.

By that measure, the overlap was even more widespread. The team found that more than half of U.S. parks are within two miles of a TRI site, while at least 63 parks share property with one. The researchers wrote, as Gizmodo reported, "[Our] results highlight that neighborhood features cannot be fully understood in isolation from each other."

Grace Noppert, an epidemiologist at the University of Michigan Institute for Social Research, and her co-authors also noted that only five states — Arkansas, Maine, Mississippi, North Dakota, and Wyoming — had no park land overlapping with a Superfund site.

Why does it matter?

This is as much a public health issue as it is an environmental one. Parks are often treated as automatic community benefits because they provide room for exercise, recreation, and stress relief, but this research suggests those benefits can coexist with nearby pollution risks.

While the study does not say every nearby toxic site is actively exposing visitors to dangerous levels of contamination, it does show that many green spaces are located near places with a history of hazardous waste or chemical releases.

Gizmodo noted the researchers warned that "research that considers parks as a monolithic public health benefit fails to consider the significant overlap between green space and polluting sites in the U.S. and the implications for communities that utilize these parks."

They also pointed to a pattern in older industrial regions and former mining areas, where redevelopment and recreation can end up layered on top of longstanding contamination. A park can still be valuable, but its surroundings matter, too.

What's being done?

The EPA already collects data on both Superfund and TRI sites, and projects like this can use those public databases to map risks more clearly. The researchers said their work can help communities and public officials better understand where green space and pollution overlap.

The team also acknowledged limitations in the current analysis. They did not break down the specific pollutants present at each park or examine how factors such as wind, terrain, and local conditions might affect the spread of contamination. 

"These places require localized attention, analysis, and advocacy to support both human and environmental health," Noppert's team wrote, as Gizmodo reported. 

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