Pollution Not Likely Cause of High Rate of Breast Cancer in Marin County, Researchers Say

The high rate of breast cancer in Marin County likely has "everything to do with demography," not pollution in the air or water, according to some researchers who have studied the issue, the AP/Sacramento Bee reports. A number of studies have found that women who do not have children or have them late in life and women who have more access to hormone supplements have an increased risk of breast cancer, and Marin County has an "unusually high" percentage of white, middle-aged women with those and other risk factors. "It's not the geography; it's the demography. It's the type of person living in Marin County," Tina Clarke, an epidemiologist at the Northern California Cancer Center, which monitors cancer rates in Marin County, said. The average rate of new breast cancer cases reported in Marin County from 1995 to 1999 was 199 per 100,000 white women, compared to 143 per 100,000 white women in other similar areas of the state. Clarke said that researchers have found breast cancer rates similar to those in Marin County among other "relatively homogenous pockets of upper middle-class white women," the AP/Bee reports. However, members of the Marin Cancer Project have called for an investigation of San Rafael quarry, a plastic foam cup factory in Corte Madera and power lines to determine whether they have contributed to the high rate of breast cancer in Marin County. In November, Rep. Lynn Woolsey (D-Calif.) and Sen. Barbara Boxer (D-Calif.) helped to obtain $900,000 in federal grants to study environmental risk factors for cancer. "Science is science, but grass-roots groups have an opportunity to work faster and gather anecdotal data that's profound and powerful," Marin Cancer Project founder Judi Shils said. Clarke agreed that researchers must conduct additional studies on the high rate of breast cancer in the county but said that an investigation of socioeconomic backgrounds and lifestyle choices of area women "would shed more light" on the problem, the AP/Bee reports (Mason, AP/Sacramento Bee, 12/5).