Environmental factors and their role in human health

Various environmental phenomena can have an effect on human health, such as eliminating the potential for life-saving medications.

"If we are cutting down the rain forests, we will no longer be able to identify chemical compounds which can fight disease," says Peyton Weary, M.D., University of Virginia. "Many discoveries come from a plant, the key compounds are isolated, and they are then synthesized and manufactured for market use."

Tropical moist forests contain half of all species. About 70 percent of the 3,000 plants identified by the U.S. National Cancer Institute as having potential anti-cancer properties are endemic to the rainforest.

Also, dermatologists have been aware of the phenomenon of ozone layer depletion and the risks that it carries because of ultraviolet radiation's relationship to skin cancer.