In 2001, the Centers for Disease Control and Prevention (CDC) released its first national study tracking personal exposures to dozens of chemicals in a representative sample of the U.S. population. The agency found that almost all Americans had an array of industrial compounds coursing through their bodies, although levels varied depending on such factors as age and gender. While many of these substances are found in everyday products, most have never been adequately tested for potential health effects.
That report heralded a wave of biomonitoring of human tissues and fluids, such as blood, urine, and breast-milk. Each of the three subsequent CDC reports has increased the number of chemicals surveyed and the sensitivity of the tests. Each new set of findings suggests there is an inexhaustible supply of ever-greater knowledge to be learned about an ever-longer list of synthetic compounds in our bodies.
Besides the CDC, academic scientists and environmental groups have also pursued biomonitoring projects in the past decade or so, adding a twist to the research mix: studies of household air and dust, a potent method of demonstrating the pervasive nature of chemical pollution. Participants in these studies have sometimes publicized their individual results to put a human face on the environmental concept of “toxic trespass.” The concept presumes that people have a right to object to industrial compounds invading their homes and bodies, whether or not these have proven health impacts.
The extensive exposures to toxic chemicals are beyond dispute; for some compounds, 100 percent of people tested in studies have been exposed. And many population-level studies have, in fact, established clear links between environmental pollutants and a wide range of adverse health outcomes, such as the negative effects of bisphenol A on women’s reproductive health.
Knowledge Gaps And Women’s Health
Yet our ability to determine the risks that these exposures pose for a specific individual has lagged behind our skill at detecting their presence. Even when we know that risks exist, we often don’t know how long the exposure needs to be, or how long until the negative impacts appear. This knowledge gap raises challenges for health care professionals seeking to counsel patients — especially those involved in pediatric and women’s reproductive health, who have grappled for years with the challenge of translating population-wide risk to individual patient health.
In 2013, the country’s largest groups of obstetricians and fertility specialists—the American College of Obstetricians and Gynecologists (ACOG) and the American Society for Reproductive Medicine (ASRM)—issued a joint statement flatly declaring that “preconception and prenatal exposure to toxic environmental agents can have a profound and lasting effect on reproductive health across the life course.”
The statement advised clinicians to counsel their patients on minimizing their exposures. (Our group, the Program on Reproductive Health and the Environment at the University of California at San Francisco, helped develop the statement.)
Not surprisingly, the American Chemistry Council responded with accusations that the professional associations were “creating confusion and alarm among expectant mothers.” The trade group insisted that current regulations reflect the available evidence and offer protection from any purported health risks.
It is understandable, of course, that chemical companies and their allies would want to deflect public attention from any suspected harms caused by their products. They argue that the documented exposures to synthetic substances should not generate concern because the presence of a chemical in the body does not mean it is causing damage.
That might be true for some chemicals, but the absence of evidence of harm cannot be presumed to mean that a compound is safe. It is not a reassuring message for women of reproductive age—or for anyone—to be told, “Don’t worry, just because intruders are in your house doesn’t mean they intend to harm you.”
Unlike pharmaceuticals, the vast majority of chemicals in commerce can and have entered our homes and lives without adequate or even any safety testing; research into potential harms has generally emerged only after the chemicals have been widely used for decades. This is a profound shortcoming of the regulations that govern industrial chemicals under the outdated Toxic Substances Control Act (TSCA) of 1976.
Congress is currently debating proposed revisions to the law, with legislation recently marked up and agreed to in the House Committee on Energy and Commerce. Health advocates engaged in this legislative process maintain that any reform should shift the burden of proof of safety to the chemical industry and require companies to provide such proof before their products are used commercially. Such an approach would represent a profound change from the situation today, which requires waiting for scientists and government agencies to demonstrate negative effects after exposures have already occurred.
Empowering Individuals With Information
Despite the uncertainties, doctors and other clinicians can offer women very useful advice. For example, diets rich in organic foods reduce exposures to pesticides, as measured by urinary levels of their metabolites. And people can choose not to buy body lotions known to contain phthalates or furniture with foam cushions steeped in flame-retardants. Indeed, advising patients on the best ways to reduce potentially toxic chemical exposures is an essential component of public health prevention.
But does telling women about chemicals in their bodies cause them unnecessary worry and stress, as chemical companies claim? And what do women themselves say they want?
With the rise in biomonitoring, a growing literature on the ethics of providing personal data to participants in such studies provides some guidance in answering those questions. In research from members of our group and others, women have consistently chosen to learn of their own chemical levels, even when they have known that this information can’t be linked to specific health outcomes. Participants deal well with the uncertainties in the science, especially when what is known and what is not known are clearly explained.
To be sure, patients in a clinical practice are not the same as participants in a study, and doctors do not routinely have specific data on individual chemical exposures to report back. But given that some substances have been found in everyone tested, clinicians can rightly presume that all patients would benefit from knowing how to minimize their risks.
And—judging by the enthusiastic feedback we have received from readers of our brochure, Toxic Matters, which offers pragmatic recommendations on how to avoid compounds known to be harmful to reproductive health—women themselves, whether in research studies or not, want access to whatever information is available about personal exposures to environmental chemicals.
Discussing these exposures in a clinical setting is consistent with the growing practice in medicine of providing patients with the necessary information to fully participate in critical health care decision-making; for clinicians to act otherwise is paternalistic and disrespectful of people’s right to know what is happening with their bodies.
And disseminating such knowledge to patients is also a first step towards preventing harmful exposures for all. In working with individuals as well as community groups, we have consistently found that increased awareness of the issue alters people’s perspectives, prompting them to engage in community activism and other efforts to reduce pollution through changes in government policy.
When it comes to toxic chemicals, in fact, ACOG and ASRM recommend that the responsibility of health care professionals does not end with advising patients. Notably, the statement also urges health care professionals to participate in policy debates about revamping our current ineffective regime for assessing and regulating industrial chemicals.
We agree that the voices of reproductive health professionals must be heard not only in examination rooms but also in their health care institutions and in the larger public debate about policies to prevent exposures to pollutants in the first place. If chemical companies want to be trusted in their assurances to pregnant women that having synthetic compounds in their bodies is safe, they should provide solid evidence of their claims before releasing their products into the world.
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