Over the past several decades, undeniable evidence has emerged that pollutants in everyday life can create significant harm to people over their lifespans. Stressors such as particulates in the air, industrial chemicals in the water supply, and preservatives in food constantly pressure the body, causing nearly undetectable changes which can ultimately result in disease or divergent physiology. Today, members of the public generally know to avoid environmental toxins like lead, asbestos, and air pollution, but few are aware of the scientific field responsible for identifying and developing coping strategies for these hazards: environmental medicine.
Walter Crinnion is a naturopathic doctor and pioneering researcher within the field of environmental medicine who has a deep understanding of the ubiquitous and under-acknowledged health hazards present in the modern milieu. While completing his professional degree at Bastyr University, he began to recognize that the roots of some illnesses lay in the environmental toxins that surround us every day and that these roots must be addressed to help patients live full and healthy lives. To investigate and educate other medical professionals about the impact of these environmental stressors, he introduced environmental medicine classes at Baystry University, University of Bridgeport College of Naturopathic Medicine, and the Southwest College of Naturopathic Medicine (SCNM). At SCNM, Crinnion subsequently founded the department of environmental medicine and sat as its first chairman until 2013. Crinnion has also founded the Naturopathic Association of Environmental Medicine, sat on the editorial review boards of the Alternative Medicine Review, the New England Journal of Medicine, and the Pharmaceutical Biology journal, and authored several books. Today, he maintains a website which documents his practices and research findings.
In this two-part interview, Crinnion shares his thoughts on some of the most pressing environmental hazards of our time and how members of the public can use the principles of environmental science to protect themselves from common toxins while enhancing overall health.
Understanding the Goals of Environmental Medicineseminal 2000 paper characterizing environmental medicine, “Chemical compounds ubiquitous in our food, air, and water are now found in every person.” The overwhelming number of chemicals to which we are now exposed and the pervasive nature of that exposure makes differentiating between the dangerous and the benign a painstaking process, as chemicals don’t necessarily have to be present in large amounts to produce harm and harm may not be immediate. Rather, environmental toxins, such as bisphenol A and vehicle exhaust, can be damaging in trace quantities when exposure is constant over long periods of time. As Crinnion says, “The bioaccumulation of these compounds in some individuals can lead to a variety of metabolic and systemic dysfunctions, and in some cases outright disease states.” It is this that serves as the central site of inquiry within environmental medicine, and Crinnion hopes that his work and the field in general can herald a more aware and healthier public.
It’s important to note that environmental medicine isn’t simply toxicology. Toxicology deals with acute illnesses caused by high levels of exposure to relatively rare toxins with little emphasis on developmental impacts, carcinogenicity, or ambient sources of toxins. Environmental medicine, on the other hand, focuses specifically on the development of chronic illnesses, congenital defects, or abnormal physiological functions that people are likely to experience as a result of contaminants or toxins which are highly prevalent in the modern lifestyle. Additionally, where toxicology studies poisons as they impact individuals at the time of acute symptoms, environmental medicine studies pollutants as they occur in populations. This means that environmental medicine can trace the population-level pathologies or physiological deviancies associated with exposure to pollutants so as to make public health policy recommendations as well as consumer protection recommendations.
Significantly, the core hypothesis of environmental medicine is that a lack of acute illness does not rule out negative impacts of common chemicals. This means that environmental medicine is also distinct from traditional medicine as a whole. “Normal medicine is what I call heroic medicine,” Crinnion explains. “You have a symptom, and I’m going to go and give you a medicine to fix it. It rarely looks at the root cause. Environmental medicine is saying, ‘What do I need to take away from the body?’ and, ‘What is poisoning your body?’” In other words, environmental medicine is concerned with removing barriers to peak function rather than adding resources to achieve peak function. However, environmental medicine researchers don’t claim to provide affirmative prescriptions to solve health issues the majority of the time. Instead, Crinnion and others interpret their role as that of academics and translators, expressing ideas and findings from the scientific literature to physicians and health officials so that they may better support the public interest.
The Impact of Endocrine Disruptors
One of the primary projects of environmental medicine is to identify pernicious chemicals which can cause subclinical yet unambiguously negative impacts on the human body. Many of the most dangerous such chemicals are endocrine disruptors, or compounds whose chemical structure is similar enough to human hormones that they behave the same way as those hormones do when in the body. Some endocrine disruptors are ingested orally as a result of contaminated food, but the majority appear to be consumed via transdermal contact with everyday objects that bear the disruptive chemicals. Endocrine disruptors are rarely toxic, but they can carry a bevy of negative health effects if administered chronically because of the way that they change cellular functions. This makes endocrine disruptors a critical area of investigation for Crinnion and other environmental medicine researchers.
The impact of endocrine disruptors varies drastically depending on the hormone mimicked and the host, but they are typically especially damaging to neonates, fetuses, and young children because hormones are essential for regulating anatomical and physiological development. In terms of systems affected, endocrine disruptors tend to be the hardest on tissues within the reproductive systems, especially for males. Indeed, chronic exposure to endocrine disruptors in males can lead to a collection of symptoms that Crinnion equates with “grumpy old men”: low testosterone during peak reproductive age, low sperm count, infertility, and, potentially, asthma. In females, exposure to endocrine disruptors can induce reproductive cancers, early ovulation, and defects of the mammary tissue. Regardless of sex, low-level exposure to endocrine disruptors increases the chance of birth defects, metabolic disorders like diabetes, cancers of reproductive tissues, neurological problems, and cancers of the mammary tissue in both sexes. Notably, this same constellation of symptoms is caused by a handful of different endocrine disruptors present in everyday objects, meaning that bioaccumulation is all but guaranteed. Because of their persistence, ubiquitousness, and negative health impacts, members of the public should be aware of common endocrine disruptors and how to protect themselves.
Among the most prevalent endocrine disruptors, bisphenol A (BPA) is especially pernicious and is generally known to the public. BPA is an omnipresent environmental hazard thanks to the chemical’s use in the manufacturing of many common products, including plastics, canned goods, and thermal paper, and may enter the body via oral consumption or skin contact. Significantly, BPA mimics estrogen and may trigger early puberty in girls and delayed puberty in boys. Later in life, BPA exposure may increase the risk of developing breast cancer in both men and women.
For fetuses and neonates, BPA is even more hazardous. Most fetuses are exposed to BPA in the womb as a result of maternal contact with products containing BPA. This prenatal exposure increases risk of developing reproductive defects. The level of severity of these defects has been linked to quantity and duration of exposure; prolonged exposure at high concentrations while in the womb can cause male fetuses to develop undifferentiated sex organs which do not occur at the same anatomical position appropriate for males. There is also some evidence that neonatal BPA exposure drastically increases the risk of developing behavioral pathologies like autism spectrum disorder and ADHD. Additionally, prenatal BPA exposure in animal models has been linked to profound deviations of the dopaminergic system of the brain, lending further support to the link between BPA and developmental, behavioral, and psychiatric disorders. As Crinnion notes, “All of these epidemic-scale public health issues are associated with finding these chemicals in the public.”
Unfortunately, BPA is so ubiquitous that it contaminates places where people least expect it. While some consciously avoid plastics that contain BPA, Crinnion notes that canned soup carries a large BPA load despite not containing any plastic to speak of, making it a silent hazard that hurts even those trying to avoid environmental toxins. Other canned goods also often use BPA as a resin liner which insulates the food in the can from the metal of the can for the sake of preserving flavor and freshness. Additionally, while many products now claim to be BPA-free, few realize that BPA is not the only bisphenol compound that exhibits toxic effects; bisphenol S is functionally identical to bisphenol A in terms of its physiological impact, and other bisphenols like bisphenol F also lurk in consumer products and food packaging. The available evidence suggests that all of the bisphenols are equally hazardous with regard to their endocrine disrupting activity.
What’s more, regulatory bodies aren’t doing enough to protect the public from products which contain the highest levels of BPA or other contaminants in Crinnion’s view. “People say, if this were a problem, the government wouldn’t let it be produced. But the public can purchase neurotoxic precursors to sarin gas,” Crinnon says. Indeed, though BPA is banned in some countries and advertised as absent in certain products, bisphenol S remains unrestricted save for a few sparse municipalities like New York City. Blanket bans of the bisphenols do not exist in the US, and the FDA has repeatedly reaffirmed its overtly counterfactual stance that BPA is harmless even as evidence to the contrary has mounted for years. Despite FDA claims regarding BPA’s safety, the EU and other international bodies have banned BPA in a handful of applications. Given the difficulty of getting regulators to protect the public when the threat is well-characterized and relatively old, Crinnion is a proponent of teaching the public to defend themselves—and the bisphenols are only one major threat out of many others.
While bisphenols are among of Crinnion’s chief concerns, phthalates are similarly threatening and carry overlapping health effects. Phthalates are chemicals used to increase the flexibility of plastics, and, like the bisphenols, are endocrine disruptors which are especially dangerous to males. “The higher the phthalates, the lower the testosterone, in men, women, and children,” Crinnion explains, “Now we have the phenomenon of 30-year-old males needing testosterone shots. Did their testicles become dysfunctional all of a sudden? They’ve been working for thousands of years, and now all of a sudden they’re not.”
In addition to their roles as endocrine disruptors, phthalates are believed to also function as metabolic disruptors, making them exponentially more damaging. More specifically, Crinnion hypothesizes that phthalates can disrupt the cellular mitochondria which are responsible for generating chemical energy for cells to use. As a result of this disruption, Crinnion links phthalates to adverse metabolic impacts like type II diabetes and obesity as well as behavioral pathologies. “Moms who have the highest levels of phthalates present have a risk of having a child with ADHD that is threefold higher than those with normal levels,” he explains, referencing a recently completed population-level study. The study, which examined a cohort of 553 children, indicates that mothers who had high urinary concentrations of phthalates during their pregnancy were 2.99 times more likely than those with low concentrations to have children with ADHD. As, Crinnion bleakly says, “All she has to do is wrap all of her food in Saran wrap, and her child can have ADHD.” Other researchers agree: phthalates are linked to the metabolic conditions as well as the developmental and behavioral disorders which have spiraled into veritable public health crises over the last 20 years.
Unfortunately, exposure to the phthalates is nearly constant. Unlike with some environmental contaminants, phthalates readily permeate through the skin, and a plethora of products, including shampoo, nail polish, and laminated flooring, are common sources of phthalate contact. In urban areas, people are also commonly exposed to phthalates in the air, and Crinnion points out that household dust is often rich in phthalates owing to their use in flame retardant ductwork. Indeed, environmental exposure to phthalates is so pervasive that most individuals never experience a total absence of it in their blood. In fact, Crinnion claims that most Americans have at least 11 of the 13 most common phthalates circulating in detectable quantities in their bloodstreams at any given time, and the CDC agrees. While avoiding phthalates altogether may not be possible, people seeking to minimize their contact should avoid flexible plastic products, insulation, laminates, paints, and epoxies wherever possible.
Perfluorocarbons and Other Threats
While the scientific community generally recognizes the dangers of chemicals such as BPA and phthalates, there are some chemicals whose hazards are only beginning to be recognized. Perfluorocarbons, for example, have maintained a reputation for being both safe and biologically inert for decades. Found in an abundance of different products ranging from cosmetics to surgical tools to drinking water, perfluorocarbons were long thought to be biologically inert, and little research was performed regarding their effects. Now, Crinnion says, new research suggests that perfluorocarbons may have bioaccumulative effects, including the development of pancreatic cancers, liver cancer, and kidney cancer. Furthermore, while the EPA has regulated the amount of perfluorocarbons in municipal water supplies since 2009, this new research indicates that the presently established limits are far too high.
The endocrine disrupting capability of the perfluorocarbons is unclear. Forthcoming research will elaborate on the risks of exposure, but at present, Crinnion’s typical environmental medicine suggestions apply: people should avoid products with perfluorocarbons whenever possible. Of course, the public may not be able to stay clear entirely due to the presence of perfluorocarbons in groundwater.
The shift in understanding of perfluorocarbons from harmless substances to potential cancer risks is significant because it so starkly underlines how much we don’t know about our chemical environments. Indeed, Crinnion’s warning regarding perfluorocarbons is only one of several that he offers regarding poorly characterized environmental threats to human health. “If you’re living a standard American lifestyle, what does that do to your risk? We don’t know,” he says. “There have been very few studies examining multiple factors because that doesn’t work with scientific theory well.” This means that chemicals which appear to be safe in isolation may, in fact, be harmful when paired with other common substances—a daunting prospect for any health-conscious member of the public.
Using Environmental Medicine To Protect Public Health
Crinnion’s overarching message is clear: people need to be aware of the chemicals in their environment, and they can’t expect the government to tell them what is safe and what is not. Pointing to the recent regulatory fiasco surrounding the pesticide chemical chlorpyrifos, Crinnion’s skepticism appears more salient than ever. Despite a long history of well-documented negative health impacts on adults, children, and fetuses, as recently as 2017 the EPA declined to ban chlorpyrifos in contradiction to the standards established by the World Health Organization. While the government’s judiciary branch ultimately passed a court order to the EPA requiring them to ban the chemical in late 2018, until that point consumers could purchase household pesticides containing the chemical. This means that nearly 20 years after chlorpyrifos was first identified by the government as causing autoimmune disorders and dysexecutive syndromes in children, Americans were still in harm’s way due to the government’s unwillingness to act on the evidence.
If banning even the most dangerous environmental contaminants can take decades when the data are unambiguous, what should the public do when the safety data are less clear or totally absent? Given that there are far too many unknowns regarding the chemicals people interact with every day, mere vigilance regarding new findings may not be enough to protect people. Recognizing this, Crinnion seeks to ward off fatalism in the public by providing a set of best practices regarding environmental health. First among these is removing that which is known to cause harm. Whether by avoiding products containing plasticizers that are endocrine disruptors or by installing filtration devices at home to prevent inhalation of ambient contaminants, the public stands to be empowered by following Crinnion’s advice closely.
To protect health in the face of ambiguous, unknown, or unavoidable threats, Crinnion advocates making the most out of the things that science knows to be healthy: eating vegetables, spending time in the sun, and getting plenty of exercise. However, performing normal health practices is not enough to provide total protection from environmental hazards, particularly when many of those hazards are not yet fully understood. As such, many people are interested in proactively providing themselves with a measure of prevention beyond the basics of healthy living. For them, Crinnion suggests incorporating a number of dietary supplements to improve the body’s ability to maintain normal function in the face of toxins. Especially for people with compromised immune systems or autoimmune diseases, this supplementation regimen could make the difference between chronic illness and health.
The greatest value of environmental medicine comes from the way it allows us to take initiative against environmental threats. Join us next week for the conclusion to our interview with Walter Crinnion to learn more about protecting yourself from environmental toxins and implementing what he calls the “holy trinity” of environmental medicine practices in your home. In the second half of the discussion, Crinnion will share with us the supplement he considers to be the most promising for the purposes of environmental medicine and explain how it can help combat the negative impact of the number one most destructive environmental contaminant: vehicle exhaust.
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