Childhood Cancer and Environmental Toxins Are Both Increasing

What is the relationship?

Roxanne Nelson

February 02, 2011

February 2, 2011 — When she was just 23 months old, Mira Brouwer was diagnosed with an ependymoma, the third most common type of brain tumor in children. A few months after her fourth birthday, after enduring brain and other surgeries, high-dose chemotherapy, radiation, a short remission, and a relapse, Mira died.

Ms. Christine Brouwer

Her mother, Christine Brouwer, is convinced that environmental toxins played a role in her daughter's brain cancer.

The case was highlighted during a teleconference sponsored by the Safer Chemicals, Healthy Families coalition. During the broadcast, experts drew attention to the increase in childhood cancers in recent decades, and the parallel increase in the use of new and mostly untested chemicals during the same time period.

Aside from Ms. Brouwer, the panel included Richard Clapp, DSc, MPH, professor emeritus of environmental health at Boston University School of Public Health, and Sean Palfrey, MD, professor of clinical pediatrics and public health at Boston University, Massachusetts.

"I will most likely never know what caused my daughter's cancer, but researchers are finding more and more links between the hazardous substances in our homes and workplaces and cancer and other diseases," Ms. Brouwer told the meeting.

After the 2008 death of her daughter, she founded Mira's Movement, an advocacy organization.

During the teleconference, Dr. Clapp pointed out that the incidence of childhood cancers, especially leukemias and brain cancer, has been on the rise for more than 20 years. Ms. Brouwer noted that during the past decade, 7 new pediatric brain tumor histologies have been identified. She suggested that there is a link to synthetic chemicals and other environmental pollutants, the use of which has risen so dramatically in recent years that they are now ubiquitous.

According to Safer Chemicals, Healthy Families, approximately 80,000 chemicals have been produced in the United States to create commonly used products — including known carcinogens such as asbestos, formaldehyde, lead, cadmium, trichloroethylene, and vinyl chloride — with virtually no government oversight.

Childhood Cancers on the Rise

"The incidence of childhood cancers has unequivocally been going up for the last 20 years, at about a 1% increase per year," said Dr. Clapp during the teleconference.

Fortunately, mortality from childhood cancer has been decreasing during this same time period, he reported.

He also noted that "we know a lot more than we did in 1975 about the things that cause cancer in both children and adults, and it's clear that at least one component of the cause is environmental chemical exposure."

"It's not in every child for every cancer, but certainly some portion of childhood cancers can be traced back to damage done at the cellular level by chemicals that are carcinogens," said Dr. Clapp.

Dr. Clapp also noted that in the past year, the International Agency for Research on Cancer reviewed more than 900 substances or kinds of exposures and identified about 107 that are known to cause cancer in humans. "When I first started looking at this, which was in about 1975, there were only about a dozen things known to cause cancer in humans," he said.

Dr. Clapp pointed to examples of chlorinated solvents, such as trichloroethylene and carbon tetrachloride, that have entered community water supplies and have been implicated in the childhood cancer clusters found in Woburn, Massachusetts, and Tom's River, New Jersey.

TSCA Overhaul

Last year, the President's Cancer Panel provided evidence that exposure to toxic chemicals is an important and underrecognized risk factor for cancer, and recommended that the government take immediate action to reverse this trend. As reported by Medscape Medical News at that time, the panel noted that it was "particularly concerned to find that the true burden of environmentally induced cancer has been grossly underestimated."

However, there was a decidedly mixed reaction to that report, with some hailing it as a landmark document and others concerned that it overstates the risks.

This law is the most egregious example of ineffective regulation of chemical contaminants.

The report from the President's Cancer Panel emphasized the need for legislation that will shift the burden of proof from the government to industry, and require manufacturers to prove the safety of new and existing chemicals. In particular, the Panel called for an overhaul of the 1976 Toxic Substances Control Act (TSCA), stating that this law is "the most egregious example of ineffective regulation of chemical contaminants."

The Safer Chemicals, Healthy Families coalition fully supports the need for updated legislation. It points out that in the 34 years since the TSCA was enacted, the Environmental Protection Agency has been able to require testing on just 200 of the more than 80,000 chemicals produced and used in the United States.

Present in Body Fluids

A number of substances are known to be related to the development of cancer, explained Dr. Palfrey. These include tobacco, ionizing radiation, asbestos, magnetic fields, pesticides, industrial solvents, and some viruses.

In normal circumstances, the body has learned to protect itself from toxins in one way or another, he said. But in the current situation, a huge number of new chemicals are entering the environment that the body has never been exposed to.

"Our bodies don't know how to detoxify themselves or to prevent these chemicals from being absorbed," Dr. Palfrey said during the teleconference. "Unfortunately, we may end up storing them."

When this happens in pregnant women, the stored chemicals can be released and circulated in the fetal blood and breast milk. "What we're finding is a multigenerational problem; if mom is exposed, it may get into the fetus."

We are not doing what we should to protect our children.

Dr. Palfrey noted that the concern is that many of these substances being released into the environment are largely untested in adults or in children, who are even more vulnerable. "People like me have been tested to see if we have some of these compounds in our blood and urine — and sure enough we do," he said.

The blood from umbilical cords has also been tested, and it has been found to contain many of these compounds, Dr. Palfrey added. "We are not doing what we should to protect our children, despite the fact that we may be very concerned about this issue."

Legislation on the Horizon?

Ms. Brouwer pointed out that the United States lags behind other parts of the world. In Europe, for example, more stringent measures have been adopted. "If companies want to sell certain products, they need to demonstrate they are safe for the intended consumer," she said. "The burden of proof lies with the company that stands to make the profit, rather than with the government. Why is our country's priority the freedom to make a profit rather than freedom from disease?"

She pointed out that the government can be slow to implement policy changes so as not to impede industry without the necessary proof. Tobacco is one such example.

Most would admit that it was about 30 years too late.

"It took many years for stronger statements to be made about the potential harm of tobacco," she said. "Now tobacco awareness and attempts to prevent lung cancer are a given. But most would admit that it was about 30 years too late."

However, new legislation directed at environmental contaminants is on the horizon. In a bipartisan effort, Sen. Barbara Boxer (D-California), chair of the Environment and Public Works Committee, introduced legislation with Sen. Mike Crapo (R-Idaho) that would assist communities in determining links between cancer clusters, birth defects and other diseases, and contaminants in the surrounding environment.

In a statement, Sen. Crapo noted that "as a 2-time cancer survivor, I know that cancer can come from many sources. This legislation may provide the answers to questions that many families face when confronting disease, and it's important that we find ways to help Americans fully understand disease clusters."

The legislation, designated S.76, is designed to strengthen federal agency coordination and accountability when investigating these potential "clusters" of disease; to increase assistance to areas affected by potential disease clusters; and to authorize federal agencies to form partnerships with states and academic institutions to investigate and help address disease clusters.


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