Researchers are looking at possible links between chemicals and high rates of advanced thyroid cancer in the gold country and other parts of California.
The thyroid is a gland in your neck. It produces hormones that regulate your metabolism. A recent UCLA study found advanced thyroid cancer rates in some California counties well above the national average.
"There are certain clusters, certain areas that are around farmlands and gold country,” says Dr. Avital Harari of the UCLA Jonsson Comprehensive Cancer Center. Harari led the study. “We can't pinpoint the exact reason as of yet. But I do think there's an environmental component."
The data show in the gold country counties of Alpine, Amador and Calaveras combined, 51 percent of the people with thyroid cancer have advanced-stage disease. The national average is 29 percent.
Harari says it's possible the higher rates could be linked to mining operations.
"It might be true,” says Harari. “It's hard to know what kind of environmental exposures are up there. Where we're finding advanced cases in those counties we're also finding advanced cases in other counties that don't have mining."
Like in San Francisco, Imperial and Santa Barbara counties.
"We did look at what is the difference in the race variable, what is the difference in the socioeconomic status variable," says Harari. "And they were actually a little bit all over the place. So it really is going to take a larger study to kind of assess for those factors as well as the environmental exposures."
The only known environmental risk factor for thyroid cancer is radiation exposure.
Harari says she'll be evaluating whether other risks could include pesticides and radon.