Code green

A cry from a sick planet

Tomer Hanuka


Until recently not many scientists investigated the impact of global warming on health.

Aside from the World Health Organization and the United Nations, few institutions have focused on the coming crisis. Noticeably absent from the efforts has been a major contributor to the environmental emergency: the United States.

“For the last several years, our government has been driving in reverse, weakening many fundamental health and environmental protections,” says U.S. Sen. Barbara Boxer (D-Calif.), the new chairman of the Senate Committee on Environment and Public Works.

But change is in the air. In January, the federal Centers for Disease Control and Prevention announced its intention to tackle health threats posed by climate change — a watershed for an agency of the Bush administration, which only last year joined the international consensus recognizing global warming as fact.

“Climate change looms as one of the major environmental public health challenges of the coming century,” says Howard Frumkin, MD, director of the CDC’s National Center for Environmental Health, which is leading the climate change initiative. “Potential health effects include heat waves, severe storms, increased vector-borne and water-borne diseases and worsening air pollution. We need research to understand the threats better; effective communication to the public, health-care providers and policy makers; public health preparedness to help protect people from harm; and primary prevention.”

Global warming is already causing illness. The WHO’s World Health Report 2002 estimated that in 2000 global warming was responsible for about 2.4 percent of diarrhea cases worldwide, and 6 percent of malaria in some countries. Deaths resulting from heat itself will continue to mount: A 2003 heat wave in Europe took at least 35,000 lives.

The world will continue to experience a warming and more variable climate for at least several decades. And the climate isn’t the only planetary system at risk. Humans have also altered atmospheric ozone, biodiversity, food production on land and sea and water cycles in ways that harm health.

It’s been a long haul to bring attention to the issue, says Christine Tam, director of Stanford’s Natural Capital Project. “People don’t grasp the connection between ecosystems and their lives and health,” she says. “We need to help people incorporate the full value of ecosystems into their decisions.” Researchers in her group are trying to make that easy by translating the contributions of nature, which they call ecosystem services, into financial terms.

Paul R. Epstein, MD, associate director of the Center for Health and the Global Environment at Harvard Medical School, notes that environmental researchers are beginning to find common ground with physicians. “These include entomologists, marine biologists and climatologists. Indeed, the number of programs addressing these issues is expanding,” he says. Internationally, close to 100 researchers are working at the intersections of these fields today, he estimates.

Encouraging news, because with human activity wreaking havoc on the planet’s atmosphere, land and water, Earth is on track to become a dead zone — unless the responsible parties change course. Either way, it will pay to be prepared for the health impacts, some of which have already hit

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