Study: Women living along Tittabawassee, Saginaw rivers may
have higher risk of breast cancer from dioxin contamination
Published: Saturday, April 02, 2011, 9:00 AM Updated: Saturday, April 02, 2011, 10:15 AM
By Lindsay Knake | The Saginaw News
The Saginaw News archives This 2007 photo shows the dioxin cleanup at the
Midland-based Dow Chemical Co. A recent report linked dioxin to higher than
average rates of breast cancer in women who lived along the Tittabawassee and
Saginaw rivers from 1989 to 2002. Women living along the Tittabawassee and
Saginaw Rivers may be at a higher risk of developing breast cancer than women
Natural Resources Defense Council, an environmentalist group, and the National Disease Clusters Alliance have released a report indicating Midland, Bay and Saginaw counties form a disease cluster, and researchers point the finger at the chemical dioxin.
The report is based on of a 2009 scientific study published in the peer-reviewed “Journal of Environmental Public Health.” It used ZIP codes in Gratiot, Midland, Saginaw and Bay counties to examine breast cancer in women from 1989 to 2002.
The New York City-based Natural Resources Defence Council and Tucson, Ariz.-based National Disease Clusters Alliance report names Dow Chemical Co. as a contributor to the pollution.
Dow Chemical, based in Midland, has acknowledged responsibility for the dioxins and furans released into the Tittabawassee River from the 1930s to the 1970s. The chemical byproducts of combustion are linked to cancer, reproductive problems and weakened immune systems in laboratory animals. Dow Chemical officials are critical of the report.
“This study did not even consider the levels of dioxin of the people in the study,” said spokeswoman Mary Draves.
It is necessary to study the individual rather than groups to determine what factors increase breast cancer risk, she said. Personal risk factors related to developing breast cancer include when women first menstruate, at what age a woman bears her first child, the number of children a woman has, whether a woman breastfeeds them and her age at menopause, she said.
The rates of breast cancer were highest in 48880, which includes the Gratiot County community of St. Louis; 48640, covering part of the city of Midland; and 48734, which includes Frankenmuth. In those areas, approximately 3 in every 100 women older than 15 developed breast cancer during the years studied. The ZIP codes were compared to 48883, Gratiot County’s Shepherd, which the study indicated is not a hotspot for industrial contamination. In that area, 1.8 out of 100 women developed breast cancer.
Three Saginaw ZIP codes — 48602, 48603 and 48604 — Essexville and Pinconning in Bay County and Coleman and Sanford in Midland County also had higher than average rates of breast cancer, with 2.3 to 2.9 per 100 women during the 13-year period.
In the study, 98 percent of the residents studied were native born.
Michelle Hurd Riddick, a member of the Bay City-based environmentalist group Lone Tree Council, said the alliance’s report is worth looking at. She said the study shows the connection between breast cancer and dioxin needs further review.
“The pink ribbons are nice, but sometimes we need to stop and turn around and ask, ‘What’s causing all of this cancer?’ ” Hurd Riddick said.
The University of Michigan Dioxin Exposure Study concluded dioxin present in the soil does not increase an individual’s body burden — the amount of dioxin in their bodies. To increase levels of dioxin in a person’s bloodstream, the person must ingest the chemical through food.
“Studies of persons with exposure to levels well above background, such as Seveso, Italy, have not found breast cancer risk related to increased dioxin levels,” Draves said.
Breast cancer rates in the three counties overall are similar to the state average.
Countywide breast cancer rates for Saginaw, Midland and Bay counties from 1985 to 2002 were near or below the state average, according to the Michigan Department of Community Health.
The annual average in that 17-year period showed 141.8 in 100,000 Saginaw
County women, 133.8 in 100,000 Midland County women and 125.7 in 100,000 of Bay
County women were diagnosed with breast cancer. The state average for women
contracting breast cancer throughout the same period was 141.2 out of 100,000.
For additional articles like this one, go to the Tittabawassee River Watch web site www.trwnews.net for complete coverage of the Tittabawassee River Dow Chemical dioxin contamination saga. . The Newspaper / Media page of our site contains an extensive archive of media articles dating back to January 2002. The source organization's web site link is listed to the right of the article, visit often for other news in our area. The Newspaper / Media page may be accessed by scrolling down to the bottom of the CONTENTS section and clicking on the Newspaper/Media link.