It’s recognized that environmental factors play a role in the development of many types of cancer, including breast cancer. But, unfortunately, there are more questions than there are answers right now about the extent of that role. Studies so far have not been able to clarify how and to what extent exposures to harmful substances in the environment increase our risk for breast cancer.
An opportunity to gain some insight on this issue could potentially come from a study now underway of male breast cancer and exposure to contaminated drinking water at Camp Lejeune in North Carolina. Results from the study are expected some time this year.
Although male breast cancer is very rare, representing less than 1 percent of all breast cancer cases, a surprisingly large number of men who lived at Camp Lejeune from the mid-1950s to the mid-1980s have been diagnosed with breast cancer. During that time, drinking water at the base was highly contaminated with toxic substances that included industrial solvents and benzene.
The study, which is being conducted by the Agency for Toxic Substances and Disease Registry (ATSDR), is examining the relationship between exposure to contaminated drinking water and breast cancer in Marines who were stationed at the base.
A Link Between Breast Cancer and Environmental Toxins?
Florence Williams, in her book “Breasts: A Natural and Unnatural History”, devotes an entire chapter to the story of Camp Lejeune and male breast cancer.
Williams notes that Camp Lejeune is the site of the most contaminated public drinking water supply ever discovered in the United States, with dozens of zones at Camp Lejeune on the Environmental Protection Agency’s National Priority List, also known as Superfund. She says this regarding an industrial area of the base, known as Hadnot Point:
…fuel tanks silently dribbled or poured close to two million gallons of gasoline into the groundwater, forming a plume of petroleum now believed to be fifteen feet thick and half a mile wide. Atop it all sat well number 602, which in 1984 helped supply water to eight thousand people and yielded a reading of 380 parts per billion of benzene. This is seventy-six times the legal limit for benzene, a known human carcinogen.
Camp Lejeune is also the site of what is apparently the largest cluster of male breast cancer cases that has ever occurred in the United States. Over 85 men who resided at Camp Lejeune have been diagnosed with breast cancer over the last decade or so.
Proven cancer clusters, where there has been shown to be a link between environmental exposures and cancer cases in a given location, are very rare. The main reason for this is that the actual numbers of cancer cases–even though them may seem high–are usually not all that large from a population perspective. This makes it very difficult for epidemiologists to conclude that the cancer cases are not simply due to chance.
Williams says that, if new insight does emerge from studying men with breast cancer who lived at Camp Lejeune, it could “profoundly alter the way we view environmental health, and breast cancer in particular.” She explains that studying this cluster of male breast cancer cases could help to solve the puzzle of this disease, because of some of the things that are unique about male breast cancer:
In looking for a link between breast cancer and chemicals, it’s much simpler to study men than women. Men’s risk factors aren’t complicated by such things as age at puberty, reproductive life history, and hormone replacement therapy. They’re just guys with a very rare disease, and rare diseases are easier to trace to environmental exposures. This cluster, unlike so many others, could prove statistically significant.
What Some Earlier Studies Have Shown
Numerous studies over the years have examined the link between the drinking water contamination at Camp Lejeune and a range of diseases among Marines stationed there and their families.
Most recently, a 2014 study reported in the journal Environmental Health examined disease mortality rates for a large cohort of about 150,000 Marines who had been stationed at Camp Lejeune starting in the mid-1970s to mid-1980s. To determine whether their mortality rates were elevated, they were compared with the mortality rates for a similar cohort of about 150,000 Marines who had been stationed at Camp Pendleton in California, which did not have contaminated drinking water.
The study found that the Camp Lejeune Marines had higher mortality rates for all cancers, as well as for a number of particular cancer types, including cancers of the kidney, liver, esophagus, cervix, multiple myeloma, Hodgkin lymphoma, and also for Amyotrophic Lateral Sclerosis or ALS.
Separately, there have been a number of studies that have evaluated environmental exposures and breast cancer. The ATSDR, in FAQs about its ongoing male breast cancer study, notes that “scientific support for the study comes from research conducted in Cape Cod, Massachusetts which suggests a relationship between exposure to volatile organic compound (VOC) contaminated drinking water and female breast cancer.”
What Happens Next?
A 2012 law provides health care coverage for Marines and family members suffering from various types of cancer and other illnesses that have been found to be associated with contaminants in the water supply at Camp Lejeune, including breast cancer.
The Marines and their families have also been pursuing claims against the Marine Corps through the court system, arguing that the Marine Corps knew about, and should have warned them earlier about, the contamination and potential harm to residents. These efforts have reached a road block, at least for now, in the form of a North Carolina law which limits the ability to make claims regarding exposures that occurred many years ago.
Science writer George Johnson, in a piece in the New York Times, says that a court decision earlier this year to stop the case from proceeding has had the effect of denying an important opportunity for a public airing of the scientific evidence about a potential link between the exposures and the Marines’ breast cancer.
Regardless of what happens with the legal case though, the results of this study could give us important information about the relationship between environmental contaminants and breast cancer.
For More Information
For more on the story of the contaminated drinking water supply at Camp Lejeune and male breast cancer, two informative articles are How a Bunch of Scrappy Marines Could Help Vanquish Breast Cancer by Florence Williams in Mother Jones and “The First Time I Knew I Had Breasts” – Leading Male Breast Cancer Advocate Passes by Kathleen Hoffman in Medivizor.
Photo Credit: s-ts via Shutterstock