Our Earth, Our Health
Eric Chivian, founder of the Center for Health and the Global Environment, worries that some medical mysteries may remain forever unsolved as a result of global climate change.
Andrew Hetherington for Proto; photographed at the Museum of Comparative Zoology, Harvard University
With the extinction of both species of Australia’s gastric brooding frog, medicine may have lost a treatment for peptic ulcer disease in humans. “We’ll never know what mysterious substance the tadpoles secreted that allowed them to hatch in their mother’s stomach without being digested,” says Eric Chivian, who worries that other medical mysteries may remain forever unsolved as a result of global climate change and loss of biodiversity. In the early 1980s, Chivian, now assistant clinical professor of psychiatry at Harvard Medical School, helped drive home to the public the idea that nuclear war in one region could devastate human health worldwide, work for which he shared the 1985 Nobel Peace Prize. More recently, he founded the Center for Health and the Global Environment at Harvard Medical School and, as its director, has worked closely with Congress and the United Nations.
Q: In your upcoming book, Sustaining Life: How Human Health Depends on Biodiversity (Oxford University Press), you write that medicine will suffer a great loss if certain organisms become extinct. How so?
A: Polar bears, for example, can help teach us how to prevent and treat type 2 diabetes: They become enormously obese from eating seal blubber before hibernating, but they don’t get the disease. Estimates are, however, that two-thirds of polar bears will be gone by 2050 as a result of global warming. Fortunately, they share other physiological wonders with nonthreatened bears: They don’t get osteoporosis during the five to nine months they den. A substance in their blood recycles calcium, and they actually lay down new bone despite being immobile. Humans, by contrast, lose as much as a third of their bone mass if they are bedridden for that long. And denning bears don’t urinate; their urea is turned into amino acids, then into new proteins. This amazing mechanism has implications for preventing and treating renal disease.
Q: You also mention that cone snails have secrets to teach us.
A: There may be 700 different species of cone snails, and each one is thought to make at least 100, maybe even 200, extremely potent toxins to paralyze prey. A synthetic derivative of one toxin is now on the market, a painkiller called Prialt. It’s thought to be at least 1,000 times more potent than morphine, and it doesn’t seem to cause addiction or tolerance. Discovering a new class of painkillers is a watershed event. Yet coral reefs, where cone snails are found, are dying in many parts of the world as sea surface temperature warms.
Q: Last August, the Center for Health and the Global Environment took evangelical leaders and scientists to Alaska to witness the destruction of biodiversity there. Why bring together two groups that couldn’t be more different in their views on the origins of life?
A: It’s clear to me that both evangelicals and scientists share a deep and profound reverence for life. Evangelical leaders need us to help them better understand environmental science because they want to explain it to their congregations, and we need them for their effectiveness in conveying the messages we agree on. Evangelicals are highly effective at communicating and, with 70 million members in the United States, have enormous political power.
Q: When you were searching for a home for the Center for Health and the Global Environment, you insisted that it be housed at a medical school.
A: We wanted the information we were disseminating to be seen as clinical medicine rather than medical research. All physicians need to understand the health consequences of environmental change because they are going to start seeing those consequences: more patients with Lyme disease and other infectious diseases, more patients with heatstroke from more frequent heat waves and more patients whose blood pressure medication needs adjusting because rising sea levels deposit salt in wells near coastal areas. Physicians are powerful advocates for the environment; people listen when we talk about matters of public health.
Q: What are the roots of your social activism?
A: I have to credit one of my medical school professors, Tom Fitzpatrick, who was chief of dermatology at the Massachusetts General Hospital and an expert on malignant melanomas. In 1971, when the United States was in a race with Britain and France to create a fleet of supersonic transport planes, Tom told the U.S. Senate that we’d see more cases of melanoma if we damaged the ozone layer with those planes. That was essentially the end of the debate in this country. I never forgot the power of a physician’s testimony about what happens to human health if we proceed down a particular path.