Plan to Test Mothers' Milk for Carcinogens

SABIN RUSSELL / SF Chronicle 23oct02

Alarmed by high breast cancer rates in some Bay Area communities, health care activists are seeking state backing for a program to screen mothers' milk for toxic chemicals that might contribute to an increase in the disease.

First-time mothers in selected locales would donate about a cup of their breast milk to the monitoring project, which would analyze it for a list of suspected carcinogens.

Yet even among breast cancer activists, the idea is controversial. Some worry that the program would send the unintended message that breast milk itself is toxic, and discourage mothers from breast feeding their newborns. Other critics say the study's goal of finding an environmental cause for the disease's high incidence rate is misguided.

Breast milk monitoring has been used for years in Sweden to keep tabs on toxic chemicals that can accumulate in the fat cells of people exposed to them.

The discovery in the milk of Swedish mothers of a chemical used as a flame retardant led to programs that, since 1998, have reduced its use in foam furniture products, and subsequently lowered the levels detected in more recent milk samples.

"If toxic chemicals are in a woman's breast milk, we know her child has had some exposure in utero," said Jeanne Rizzo, executive director of the Breast Cancer Fund, a San Francisco organization that is proposing the monitoring project.

Marin County, which saw annual breast cancer cases increase at six times the rate of neighboring counties during the 1990s, would be a prime candidate for the project. Rizzo said women in cities such as Richmond, and communities such as Bayview-Hunters Point in San Francisco, which also have higher breast cancer rates and concerns about toxic chemical exposure, are also likely to be involved.

Rizzo has no estimate of the cost of a statewide monitoring program but acknowledges it would cost "millions." Key to the California plan is to develop a standard set of rules for running such programs, so the results are dependable and easy to compare from one region to the next.

"We want to create a model, an exemplary program," Rizzo said.

The idea will be presented to state legislators today during a joint hearing before the Senate and Assembly health committees, meeting at 10 a.m. in the Board of Supervisor's chambers in San Francisco's City Hall.

Although breast milk affords a quick way to determine if toxic chemicals are present in the environment, the idea has drawn criticism, particularly from those who have struggled to promote more breast feeding of U.S. infants. Rizzo said the program would be designed to reassure women that it is still far healthier to breast feed their babies.

But other critics say the emphasis on breast-milk screening is off base -- that it might detect contaminants, but at levels so low no one could prove that they might play a role in causing breast cancer. Pollutants are among a long list of factors suspected in the development of breast cancer. Genetics, hormone use and diet may also play a role.

"Intuitively, people will say, 'Oh, toxins in breast milk!' But the pathways for the development of breast cancer are likely to be quite different, " said Barbara Brenner, executive director of Breast Cancer Action, another San Francisco activist organization.

WITHDRAWS SUPPORT

Because of their reservations about breast milk monitoring, the group withdrew their support of today's legislative hearing.

Casting a shadow over biomonitoring efforts is the failure of a costly study of Long Island women to find any significant link between breast cancer and exposure to agricultural pesticides and other toxins. The $8 million study analyzed blood and urine samples, and was limited to a short list of known carcinogens.

The program was pushed by lawmakers and activists inspired by reports that women in Long Island had a breast cancer rate that was 30 percent higher than average. Yet it turned out those estimates were simply wrong: The disease incidence was only 1 percent higher than the national norm.

"They studied the wrong thing," said Brenner, who believes science still lacks the tools to look back, over time, at the multiple factors that might lead to cancer.

Nevertheless, testimony scheduled for the hearing will present evidence on the link between rising breast cancer rates and the accumulation of toxic chemicals in the environment. It will include a report from a Centers for Disease Control-funded summit on breast cancer and the environment, convened in May in Santa Cruz. The summit recommended a nationwide "biomonitoring" program.

'HITTING THE LIMITS'

Dr. Gina Solomon, of the Natural Resources Defense Council, agreed that science has difficulty getting to the root of diseases like cancer that are caused by multiple factors, but still supports milk monitoring. "We're hitting the limits of what science can tell us. We need new tools," she said. "One of the hottest new tools is human exposure monitoring."

Sharyle Patton of Commonweal, a Bolinas social research institute, said the recently signed United Nation's Persistent Organic Pollutants Treaty will spur biomonitoring programs to assure compliance.

"Breast milk is easier to monitor than blood," she said.

But Patton stressed that it is essential to combine milk monitoring efforts with programs that promote breast feeding, "so women are not left with the impression that breast milk is contaminated."