If our smog doesn't rot your lungs, the sun shining through may attack your skin.

Lung and skin cancer rates in the Great Lakes region, the province's smog belt, are higher than Ontario averages.

Experts point to the environment as the culprit.

Greater use of chemicals, from farming to industry and society in general, has produced higher rates of lung cancer unrelated to smoking.

And a thinning ozone layer has added to increased ultraviolet radiation from the sun that leads to skin cancer.

In the two health-planning zones of Southwestern Ontario, Erie St. Clair and the South West, death rates from cancers and tumours are higher than Ontario's rate.

Bad air that blows into the region from the U.S. industrial midwest, topped with toxic discharges from Sarnia's Chemical Valley, and heated by the hottest sun in the Great Lakes, is a recipe for cancer.

Scientists concede more research is needed into suspected links between the environment and cancer, but some links are already established:

LUNG CANCER

"Air pollution is certainly a major contributor to lung cancer," said James Brophy, executive director of Occupational Health Clinics for Ontario Workers in Sarnia.

An expert in occupational and environmental cancer, Brophy said the clearest link between the environment and cancer has come in the workplace, a relatively closed environment with consistent and measurable contaminants.

Brophy calls workers in Sarnia's Chemical Valley the "canaries" in the environmental coal mine, because of their close proximity to pollution.

"In Sarnia, we have a poisoned airshed and we are further poisoning it with our own emissions," he said, noting all that bad air moves east on prevailing winds to places such as London and Woodstock.

SKIN CANCER

Bad air is getting under people's skin -- literally.

The sun's ultraviolet light causes skin cancer, and the impact of that light is magnified as it passes through smog.

Pollution, said London researcher Lina Dagnino, who studies the formation of skin cancers, contains chemicals with "oxidative agents," which are known to "co-operate with UV to make things worse and cause cancer."

A link has been found between oxidative agents in creams to control psoriasis that actually increase susceptibility to cancer, she said.

Such agents can be found in a wide variety of chemicals in poor-quality air, said Dagnino, an associate professor of physiology, pharmacology and obstetrics at the University of Western Ontario.

While skin cancer accounts for one-third of all cancers, Dagnino said, a good prognosis can result from early detection and treatment. "Very few people die from it," she said.

Research into the combination of ultraviolet radiation and pollution is in its infancy, she conceded. "This is something we are just starting to look at."

Besides chemicals and fine particles that sweep across the region, stagnant, ground-level ozone on smog days also magnifies ultraviolet radiation.

"My prediction would be there may be a link between exposure to ozone during pollution and an increased risk for skin cancer," she said.