It’s not every day that an environmental activist becomes a leading voice in health care, but that’s what happened to Gary Cohen, a new MacArthur fellow. By looking under the hood of hospitals, he’s discovered a few nasty secrets — and inspired big changes for a community of scientists and practitioners whose healing practices were actually hurting the world around them.

“We want hospitals to clean up their own house,” said Cohen, whose organization, Hospitals Without Harm, has managed to tackle issues as diverse as the use of mercury in medicine and what hospital patients eat. A keen environmentalist, Cohen’s ears perked up in the 1990s as he started to hear about endocrine-disrupting chemicals like dioxins. These nasty compounds are found in the environment, but they persist in the fatty tissues of humans and animals, messing with hormones, compromising the immune system and even causing cancer. When Cohen heard that hospitals were the largest source of dioxin emissions in the United States, it stopped him in his tracks.

“Hospitals were the poster child for this chemical,” he recalled, noting that they then had to treat people whose endocrine systems they’d destroyed. “It was insane! Hospitals were poisoning people in the service of healing them.” Cohen started digging, lifting the proverbial log that was the health-care system and finding a seething underbelly of bugs, dirt and distasteful practices. Not only were hospitals spewing dangerous chemicals into the environment, but they were also disposing of huge amounts of mercury from thermometers — mercury that then made its way into the water supply, fish and back into human bodies.

And then there were the incinerators. At the time, hospitals burned most of their trash. Cohen remembers seeing plastic tubing, pizza boxes and even computers thrown into on-site incinerators along with medical waste like pharmaceutical products. But when he and his colleagues contacted hospitals to find out who was in charge of regulating their stoves, they learned that they were being advised by incinerator salespeople, not sustainability experts.

“Like a good patient, they needed a second opinion,” Cohen said while laughing. He can laugh now — in part because of his efforts, the American health-care system has reduced the use of incinerators, which once numbered in the thousands, to fewer than 70 nationwide. Some medical waste is still burned, but the scope has been narrowed.

Cohen sees the problem with health care as one of miscommunication. Hospital administrators don’t always realize that it can cost less to implement sustainable practices, especially ones that allow them to flex their buying power to further drive down cost. Professional training is a concern, too. “The typical doctor may have four hours of environmental education in four years of med school,” he said. “They learn about tobacco and alcohol, but they’re not trained to understand environmental health. We’re not training the next generation of doctors to even understand these issues, let alone look for the symptoms of how it might affect patients.”

There’s still work to be done — and lots of it. Hospitals themselves admit that they are part of the problem: In 2012, the Healthier Hospitals Initiative estimated that the average hospital generates 26 pounds of waste per staffed bed per day. (That’s exponentially higher than the average of 4.40 pounds of solid waste the Environmental Protection Agency estimates is produced by individual Americans). And a 2014 Harris poll sponsored by Johnson & Johnson found that just 22 percent of hospitals have a current purchasing policy that takes the environment into consideration.

But Cohen doesn’t seem daunted by those odds. “As a society, we’re only now coming to realize how profoundly a polluted environment affects public health,” he said. After all, says Cohen, in the past “there was almost no consciousness about the environmental footprint of health care.” Now, with the help of his MacArthur grant, Cohen wants to see “cancer centers without carcinogens and children’s hospitals without chemicals linked to birth defects.”

It’s all a matter of being involved in the solution, he says — no matter how dark the problems you uncover under the hood.

Erin Blakemore (@heroinebook) is a freelance journalist from Boulder, Colo. She is the author of "The Heroine’s Bookshelf" (Harper). 

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