Any molecule with an unpaired electron is known as a free radical. Free radicals have been implicated in heart disease, cancer, Alzheimer's disease and other chronic diseases associated with aging. In general, your cells protect you from oxidative damage, but if you are exposed to a lot of free radicals, ultimately your DNA will suffer more damage. . . . Among the free radicals Burrows studies is a substance named peroxysulfate, which is formed when sulfur dioxide air pollution reacts with water and oxygen, or when sulfite preservatives from wine, dried fruits or certain other foods react with oxygen. Free radicals may be created when peroxysulfate is formed in the presence of certain metals, such as nickel, iron, manganese, cobalt or copper.
Many people inhale particles of such metals, either on the job or from air pollution.
In Sudbury, Ontario, such exposure has been associated with cancer among nickel miners, said Burrows. Cells might die if enough of their DNA is damaged, preventing the cells from making proteins necessary for survival. So Burrows said it is possible DNA damage triggered by oxidation reactions involving airborne nickel or other metals also might cause lung damage by killing lung cells. Her own research didn't involve showing how DNA damage can lead to cancer or other ailments. These kinds of studies will aid in ultimately understanding how air pollution causes illness.