Can We Prove a Link Between Environmental Toxins and Autoimmune Disease?

There is almost universal agreement among leading experts at top medical institutions –Johns Hopkins, Harvard Medical School, the National Institutes of Health, Scripps and others –that our day-to-day exposure to environmental toxins — through the air we breathe and the chemicals we absorb through our skin — is a major trigger of autoimmune disease.
However, because most toxins are found in trace amounts, it has been difficult to gauge what effect they might be having on our health. Yet both lab animal and occupational studies of human beings provide us with disturbing insights into how even low exposures to chemicals can cause our immune systems to go haywire. For example, mice exposed to common pesticides – at levels four-fold lower than the level set as acceptable for humans by the EPA – are more susceptible to getting lupus than control mice.  Mice that absorb low doses of trichloroethylene (TCE) – a chemical used in industrial degreasers, and that can be found in your dry-cleaning, household paint thinners, paint strippers, glues and adhesives – at levels deemed safe by the EPA, and equal to what a factory worker today might encounter, quickly develop autoimmune hepatitis.  And low doses of PFOA, a breakdown chemical of Teflon – which can be found in nonstick cookware, car parts, flooring, computer chips, phone cables, Stainmaster carpet guard, upholstery, new clothing (particularly kids’ clothing), grease-resistant French fry boxes, the disposable cup of soup that you warm up in the microwave, and disposable coffee cups like the ones you get at your local coffee shop) — can be found in 96 percent of humans tested for it.  In recent studies, immunotoxicologists have been unable to find a dose that didn’t alter the function of immune cells at each major step that the immune system takes in trying to protect us against foreign invaders.
Even tiny doses of BPA, a plastics building block used in everything from safety helmets, dental sealants, baby bottles, and eyeglass lenses to every-day processed food packaging, has been shown to change basic cellular function at levels currently present in blood samples taken from people as well as animals.
Proving an absolute link between chemicals and autoimmune disorders in humans is hardly easy.  Researchers can expose rodents to low doses of chemicals and look for signs of autoimmune disease roughly six weeks to three months later.  But in humans, a comparable time span between exposure and disease might be forty years.  Indeed, lab work in longitudinal studies of people shows us that autoimmune diseases are often long, slow-brewing conditions that can quietly smolder in the body for a decade or more before actual symptoms of disease appear. Moreover, it may be that a combination of exposures rather than any acute single dose at a single time increases one’s risk of autoimmunity, conditions that are hard to replicate in animal studies.
I suspect that on some level we don’t want to face what all this research is telling us. We don’t want proof, because even if we agree that the soup of chemicals we’re all carrying around within us is harmful, what do we do about it?  Talking about the autoimmune epidemic is a bit like talking about global warming before the movie An Inconvenient Truth was released. For the longest time, we couldn’t see, or didn’t want to see, that the smallest rise in temperature would melt the polar ice caps.  Likewise, we don’t want to know that the ways we’re polluting our environment are also harming our bodies and causing our immune cells to go haywire.  In the international medical world, the scientists who study autoimmune disease now call this epidemic “the global warming of women’s health.”  Yet the reality that the environment plays a major role in triggering these diseases hasn’t yet trickled down to the rest of the population.

Becoming Part of the Solution

Is there anything we can do as individuals and as a nation to halt this epidemic – or at least lower the stakes for future generations?  One step I’d propose is to take a page from European environmental policy, which uses the precautionary principle — an approach to public health that underscores preventing harm to human health before it happens.  In June 2007, the European Union implemented legislation known as REACH (the Registration, Evaluation, Authorization and Restriction of Chemical Substances).  REACH requires chemical and industrial companies to develop safety data on 30,000 chemicals over the next decade, and places responsibility on the chemical industry to demonstrate the safety of their products.  By contrast, in the U.S., chemical companies are not required to do any testing to ensure chemicals do not harm the immune system.  Chemicals are presumed innocent – unless scientists can prove otherwise, which can take decades and can only be done if there is a source for funding.

It would also be helpful to raise more public awareness about the problem by giving the environmental triggers of autoimmune disease a name.  Despite all this mounting evidence, there still exists no word comparable to “carcinogens” in our cultural lexicon to describe the notion that environmental chemicals might be linked to autoimmunity. The term “autogen,” I believe, would prove useful to refer to the toxins, viruses, and every day chemicals we know can play a role in triggering autoimmune disease.

The National Institutes of Health recently stated that investigations of exposures to chemicals as triggers for autoimmune disease are now of “considerable research interest.”  That may be true, but they have yet to show researchers the money.  With 24 million Americans  – and one in nine women – suffering from autoimmunity, the NIH allocates only $591 million dollars for autoimmune disease research each year.  Contrast that with the $5 billion annual budget for cancer, which afflicts 9 million Americans.  The NIH budget for cardiovascular disease – which affects 22 million Americans – is four times that of autoimmune diseases.  We have waited too long for Congress to allocate funding to find out what toxic exposures, or combination of exposures, can cause our immune systems to turn against us.  Congress needs to do better.

The Hygiene Hypothesis

Some people believe that the sole cause of rising rates of immune-mediated disorders is due to what is called “the hygiene hypothesis.”  The hygiene hypothesis holds that the root cause of rising rates of immune related diseases stems not from the fact that we are living in too dirty a world, but, rather, from the fact that we are living too clean.  In other words, our lack of exposure to certain viruses and the swill of bacteria that most of our ancestors were exposed to living without vaccines or modern hygiene means children’s immune systems are no longer forced to build up the necessary immune defenses they need.  In a world of well-vacuumed homes, scrubbed bathrooms and more time spent in minivans than mucking about through the woods and farmland, coupled with massive vaccination programs that prevent full-fledged infection from many childhood diseases, our immune systems are, in a sense, overprotected.  They have so little to react to that they may be overreacting to anything – kind of like a bored teenager who is likely to get in more trouble when they don’t have enough to do.

However, immunotoxicologists at our research institutions agree almost universally that the hygiene hypothesis is hardly enough to fully explain today’s autoimmune epidemic.  At the same time that we are living with fewer exposures to natural pathogens, we are coming into contact with many times more artificial invaders in our day-to-day lives.  So that at the same time our immune systems may be confronting less natural dirt and muck and deadly outbreaks of disease, we’re encountering an endless slew of artificial toxins that confuse and overtax the immune system.  Interestingly, immigrants from other countries who are exposed to numerous infections and have few vaccines as young children develop allergies and autoimmune disease at rates similar to those of Americans soon after they immigrate to this country.

An Uncontrolled Human Health Experiment

Today, 80,000 chemicals are registered for use in the U.S. and the EPA approves 1,700 more a year – an average of five a day – without any testing as to whether or not they pose a challenge to the immune system.  This may well prove to be our next environmental disaster in the making – only this time the frightening changes taking place degree by steady degree are within the invisible, interior landscape of our bodies and not the global climate.  As one Johns Hopkins’ researcher put it, we’ve outpaced our evolutionary ability to keep up with the number of toxins we come into contact with everyday.  It takes the human body thousands of years to adapt to new environmental stresses – yet in less than a hundred years we’ve dumped so many toxic substances into our environment that our immune system is being asked to differentiate between our own body and unrecognizable foreign invaders non-stop.  Which makes our body so much more likely to make mistakes and turn on itself.

Today’s children are the high stakes pawns in this game: pound for pound they eat more food, drink more water, and breathe more air than we adults do, and their immune systems are still developing and vulnerable.   It’s as if we are all unwitting participants in an uncontrolled human health experiment as we document how the rising levels of toxins and pollutants in our blood are resulting in climbing rates of autoimmune disease.

Workers at Risk

There is mounting evidence from occupational studies of the link between environmental toxins and autoimmune disease. In 2007, scientists from the National Institutes of Health announced a new report on exposures to chemicals and death from autoimmune disease.  After studying 300,000 death certificates in 26 states over a 14-year period, researchers found that people who worked with pesticides, textiles, hand painting, solvents (such as TCE), benzene, asbestos, and other compounds were significantly more likely to die from an autoimmune disease than people who were not exposed.  Other recent studies likewise show links between working with pesticides, TCE solvents, silica, asbestos, PCBs and vinyl chloride and a greater likelihood of developing autoimmune disease.

An Ominous Coincidence

Ironically, during the decades from 1940 to 1980 — when the medical community believed that autoimmune disease was impossible – the United States was simultaneously engaged in the greatest industrial growth spurt of all time. All across America, production plants were starting to spring up in town after town, as corporations ramped up production of thousands of novel products manufactured through efficient new chemical processes. New pesticides were being introduced to boost crop yields, prolong the shelf life of produce, keep lice, fleas, roaches, and termites out of the home, and zap dandelions from the lawn. Ingenious new chemicals were being used to help manufacture everything we Americans wanted to make our lives easier, simpler and more luxurious – from plastics to hair shampoo, detergents, foam cushions, carpeting, cosmetics, paint strippers, dry cleaning fluids, household cleansers and bleaches, and bigger, grander cars. Almost overnight, Americans began to find themselves inundated with and clamoring for the suburban home products, packaged goods, and manufactured foods churned out by mega-industry. Fleets of trucks transported these newly manufactured goods from coast to coast, and the ChemLawn truck began to circle the cul-de-sacs in neighborhood after neighborhood.
But this coincidence in timing – between a medical community not yet educated about a mysterious, growing set of diseases with an unknown set of triggers and a society’s swell in production of everything from SUVs to Teflon pans to furniture and mattresses that have been stuffed with flame-retardant foam – would turn out to be an ominous one.

The Toxins in Our Bloodstreams

In 2004, the CDC sampled 2,500 people across the country looking for the “body burden,” or amount of chemicals and pollutants each individual was carrying. They found traces of all 116 chemicals and pollutants they looked for, including PCBs, insecticides, dioxin, mercury, cadmium and benzene, all highly toxic in higher doses.  Then, in 2005, researchers found something more alarming: a cocktail of 287 pollutants — pesticides, phthalates, dioxins, flame retardants, and breakdown chemicals of Teflon — in the fetal cord blood of ten newborn infants from around the country, in samples taken by the American Red Cross.  A few months ago, CNN headlined the story of an 18-month-old and five-year-old who were selected and tested at random for industrial chemicals and found to have toxic chemicals coursing through their bloodstreams at levels several times higher than those already known to cause health problems in lab animals.  Meanwhile, levels of a number of chemicals now found in women’s breast milk have been doubling every five years – and are particularly high in American women.

The Barrel Effect–or, it’s the Last Straw that Breaks the Camel’s Back

Each person, with his or her unique genetic composition, is exposed to a unique combination and level of autogens depending on what they encounter in their day-to-day lives through the air they breathe, the substances that come into contact with their skin, their stress levels, their diet and their genetic predisposition. Chemicals and heavy metals, additives in our highly processed twenty-first century diet, and viruses and bacterial agents to which we’re exposed all combine to impact our immune system. Chronic stress, which releases a slow drip of cortisol into our body, also plays a role in triggering autoimmune diseases. As long as your barrel is less than full, however, your immune system is still able to deal with what it confronts every day. But once the immune system becomes overburdened and that barrel fills to capacity it can begin to misread signals, causing the immune system to make costly mistakes and attack the body itself. Unfortunately in modern life we’ve created a perfect storm of factors – a plethora of chemicals, heavy metals, processed food additives, viral hits and stressors – for today’s autoimmune epidemic to take hold. So much of what we encounter in twenty-first century life is causing our barrel to fill to the brim – and spill over. At that point, disease strikes.

Recently, researchers at the Bloomberg School of Public Health at Johns Hopkins reported that even people without a genetic predisposition are vulnerable to autoimmune diseases. Whether or not you get an autoimmune disease depends on how many of these triggers you’ve been exposed to over your lifetime – or how full your barrel is. People with a genetic predisposition may be more vulnerable, but anyone whose immune system is overtaxed or over-stimulated can develop an autoimmune disease.

How to Protect Yourself

What can we do to protect ourselves and our families, and our immune systems? If you know what can contribute to disease it’s easier to know how you can help yourself. Dietary factors, use of household cleaners, emotional stress—these all have to be watched and managed –I go over each of these in detail in the Autoimmune Epidemic. Studies show that patients with an autoimmune disease also do better if they build a wellness plan that involves reducing stress hormones through a daily habit of meditation and whatever form of exercise they can tolerate. Patients also do much better if they follow “the autoimmune diet,” which means consuming foods that are anti-inflammatory, or a whole foods, rather than a processed foods, diet. I have a detailed description of the autoimmune diet in the book. One also needs to work with a doctor who is open to treating you not just with drugs but also with dietary changes, including making sure you’re receiving adequate amounts of the main supplements that have been shown in clinical studies to help autoimmune disease patients, such as omega fatty acids, Vitamin D, antioxidants, probiotics, and glucosamine.

Looking into the Future

I often wonder if in seventy years we will have classrooms of students grilling teachers as to why their grandparents and great grandparents – you and me – weren’t more concerned about toxic contamination and the immune system. Didn’t we see what we were doing to ourselves, to our foods and water, to future generations? Didn’t we grasp the connection between the environment and skyrocketing rates of diseases in which the immune system runs amok?

On the other hand, perhaps in the future we will all have made enough educated choices, exercising cumulative veto power as consumers and demanding accountability from
government officials and agencies, that that roomful of high school students won’t be pressing teachers as to why we didn’t foresee the polluted, disease-laden legacy we were leaving behind. Rather, they’ll be asking how a generation of scientists, researchers, patients and concerned parents were prescient enough to come together to stop an autoimmune epidemic in its tracks. There can’t be a better legacy – to leave our children than that.