Nov. 6 (HealthDay News) -- New research suggests that living near a volcano puts people at higher risk of getting a type of thyroid cancer.

It's not clear how volcanoes might be related to cancer, but researchers suspect that the toxic compounds they produce could play a role.

Researchers are also unsure of why thyroid cancer rates are rising around the world. It's possibly because of better detection, but the environment is a potential factor as well, they believe.

The study authors examined reports of newly diagnosed thyroid cancers on the island of Sicily from 2002 to 2004. They compared the cancer rates in residents from two areas: those who live in the volcanic area around Mount Etna and those in the rest of Sicily.

Researchers found that those in the province of Catania, near the volcano, had more than double the rate of papillary thyroid cancer -- but not follicular or medullary thyroid cancers -- than other residents of Sicily.

"The striking increase in papillary thyroid cancer incidence that was associated with the Etna volcanic environment leads us to suggest that residents of other volcanic areas could be at increased risk for thyroid cancer and, possibly, of other cancers," the authors write. "Although specific risk factors for thyroid cancer in this volcanic environment are still unknown, identification of these factors could help to better understand the cause(s) of the increasing thyroid cancer incidence in Europe and North America and perhaps to develop prevention measures."

The findings are in a study published online Nov. 5 in the Journal of the National Cancer Institute.

SOURCE: Oxford University Press, news release, Nov. 5, 2009