A sunny September afternoon on Long Island, New York.
It’s 1956, a simpler time. Neat houses, all identical, are lined up in a row; the recently planted trees are still young. Children play outdoors on green lawns while large American cars glide slowly by. The sun shimmers on the freshly poured concrete driveways. A dog barks in the distance. Nobody is in much of a rush, and this little patch of America is tranquil.
Back in that simpler time, everyone shopped at the grocery store. There were no superstores. No health food stores. No Starbucks, not yet. That would have to wait. If you wanted coffee, you made it yourself or had it in a restaurant, poured into a ceramic cup. To-go cups? Not a chance.
It was a time, too, when allergies were out of the ordinary. Allergies were something you had heard of. Perhaps you knew someone who was allergic to pollen. Perhaps you knew someone who was allergic to cats. Perhaps you didn’t know anyone who had allergies at all. Allergies were rare—and this was only 50 or 60 years ago, a very short time from an evolutionary perspective.
Fast-forward to today. There are a growing number of people allergic to an expanding number of things. One billion people worldwide now suffer from allergies, according to the European Academy of Allergy and Clinical Immunology.1 The rate of allergies is rising in both the developed and developing world, the World Allergy Association has announced.2
And the classic allergens such as pollen and dust have been joined by a whole new bunch of allergens. Ordinary, everyday food items that once seemed safe have become a major problem for millions of people. Wheat. Milk. Eggs. Peanuts. And numerous other foods.
Leading medical journals have proclaimed an epidemic of asthma, and rhinitis has been on the rise. Millions suffer from wheezing, coughing, congestion, burning eyes, and itchy skin. Many more have brain fog, fatigue, weight gain, insomnia, and other symptoms linked to the sorts of hidden allergies we discussed in the last chapter. One thing is clear: people are responding in a vigorous allergic way to the changing world in which we live. And this is only the beginning.
Why Are We So Allergic?
So when, you may wonder, did everything become something we had to worry about? When did so many of us become so dangerously allergic to so many things?
Scientists seeking answers to these questions agree that the rise of allergies is not the result of genetic changes. The period of time we’re looking at, about half a century, is too brief to allow for changes in our DNA.3 Instead, they are exploring how the environment we live in and our modern way of life are responsible for the allergy epidemic.
As I said in the Introduction, allergy arises from your nutrition and your environment—and environment impacts allergy on three levels: outdoors, indoors, and inside your body. The food you eat affects your body’s response to allergic triggers at each of these levels. Throughout this book I’ll note ways in which the modern Western diet promotes inflammation and allergy by undermining the function of T-reg cells, key players in your body’s immune response.
The research has been done. The data has been analyzed. Science has once again told us that the food we put in our mouths has a huge impact on our health. And when we frequently eat at fast-food places, we may be getting more than we ordered.
While fast food has long been considered a hallmark of life in America, this form of eating, with its typically high-fat, high-sodium, and high-carbohydrate meals, has spread around the world. Now a major international study by 144 researchers—the International Study of Asthma and Allergies in Childhood (ISAAC)—reveals that rising consumption of fast food could be contributing to the rise of allergies in children and adolescents.
Data was collected from more than 181,000 children from 31 countries and more than 319,000 adolescents from 51 countries to look at the role of eating patterns in asthma, rhinoconjunctivitis, and eczema. The results include both males and females, in countries that are developed and those that are less developed.
The researchers found that for adolescents, eating fast food three times per week or more was associated with:
For children, eating fast food three times per week or more was associated with the same symptoms, with the exception of current eczema, for which no link was identified in the study.
The study went on to explain the nutritional components that make fast food such a problem. The link between fast food and allergic diseases and asthma is probably due to fast food’s typically higher levels of:
On the bright side, the study found that eating fruit three or more times per week was associated with a protective effect in asthma and rhinitis for the adolescents and for all three conditions—asthma, rhinitis, and eczema—in the children.4
Changes in your body’s inner ecology play a part as well. Each of us is naturally colonized even before birth by an army of microbes—bacteria, yeast, viruses—that stay with us throughout life, shaping the function of our immune systems. Each person’s characteristic population of microbes is so distinct, in fact, that criminologists are beginning to use this pattern the way they use fingerprints to identify perpetrators. And abnormalities in your resident microbes have been linked to the development of allergy. Swedish researchers followed children from birth to five years of age and found that the absence of certain bacterial species preceded the development of allergic disorders.5 Research in this area is just getting started. Later in the book I’ll discuss studies on the use of beneficial bacteria—probiotics—to improve different allergic conditions, and I’ll discuss some cases where probiotics were part of the allergy treatment.
What about the outer environment? We all have to breathe, and every one of us is affected on the most profound biological level by what is in the air. To explain the rise of allergies and asthma, science points toward rising levels of air pollution and exposure to toxic chemicals and pesticides, alongside poor eating habits, smoking, lack of exercise, and increased stress.
Ambient air pollution due to motor vehicle exhaust, cigarette smoke, and manufacturing produces oxidative stress that harms the lining of your respiratory tract and sensitizes you to airborne allergens. People living near heavy-traffic roadways are particularly vulnerable.6
Synthetic chemicals found in food and water act on your cells to shift the way in which your immune system responds to stress, so that your immune responses favor allergic reactivity. And there is more. Greenhouse gases such as carbon dioxide, primarily from coal-burning power plants, cars, trucks, and industry have made the earth warmer, producing a greenhouse effect that affects all forms of life—including increasing the growth of allergenic plants and those plants’ production of allergenic pollen.
Dr. Maria Neira, director of the Department of Public Health and the Environment at the World Health Organization, urges us to realize the scope of the problem: “Consider air pollution, the single greatest environmental health risk we face. In 2012 alone, exposure to indoor and outdoor pollutants killed more than seven million people—one in eight deaths worldwide.” She adds, “Since 2007, I have described climate change as the defining issue for public health in this century.”7
Mother Nature’s Allergic Reaction
Scientists are working hard to understand how global warming is making conditions worse for allergies and asthma. Two examples are through an extended pollen season and through plants that produce more pollen than before.
Perhaps the postwar economic expansion of the 1950s, the time I mentioned at the start of this chapter, held the seeds of the problem. A never-before-seen boom of industrialization and rapidly changing ways of living caused a vast array of dramatic shifts in a very short time.
In the postwar era, we began to see not just a few more cars and trucks, but millions more cars and trucks. In 1960 there were already 74 million vehicles on the road in the United States, and 5 million vehicles in Canada. By 2002 the number of vehicles in the United States had increased to 233 million, and Canada had 18 million.8 The number of cars on the road around the world in 2010 surpassed one billion.9
Thanks to the millions of barrels of oil being pumped out of the ground, gas was cheap, and new products were born from oil, like plastics and chemicals. The chemical industry took off, producing hundreds of thousands of new substances. New houses sprang up like mushrooms in empty fields that had been productive farmland. Supermarkets spread across the country, and we were introduced to mass marketing of thousands of new processed foods. Bread, which had from time immemorial been baked by hand, was now produced in a factory, sliced and wrapped in plastic, and sent out to stores.
An unbelievable assortment of cookies, candies, ice creams, and sodas became available. So we began indulging our collective sweet tooth with not just a little more sugar, but tons more sugar. The use of margarine increased dramatically as it replaced butter for baking pies and spreading on toast, with consumers totally unaware that the artificial trans fats it contained were dangerous to their health.
Pollen Forecast: Double Trouble on the Way
Lush green grass is a big part of the American dream. Cutting the lawn, watering the lawn, is a shared experience. But the tall wild grasses that grow like weeds in any empty space produce a lot of pollen. You may have seen them; they have a big flower head that looks like a dust wand. The pollen from this grass is highly allergenic; it causes allergic reactions in 20 percent of the general population and in 40 percent of people predisposed to grass allergy.
Now scientists from Harvard University and the University of Massachusetts–Amherst have forecast how much more grass pollen we can expect when more carbon dioxide gets pumped into the air in the coming decades. They have concluded that carbon dioxide, which comes from burning fossil fuels, will double by 2100, and that doubling the carbon dioxide will have the effect of a giant greenhouse, doubling the number of pollen-producing grass plants. In addition to more plants, the experiment revealed that the amount of pollen per flower will be boosted by 50 percent.
“The implications of increasing CO2 for human health are clear,” the study authors explain. “Stimulation of grass pollen production by elevated CO2 will increase airborne concentrations and increase exposure and suffering in grass pollen–allergic individuals.”10
Our Environmental Crisis Is a Health Crisis
From the places we live and work to the air we breathe to the food we eat, everything has changed. The world we live in, what seems normal to us, is now remarkably artificial. We live in an environment that has been completely transformed by the actions of humankind. Most of us now live in cities and suburbs; you would have to go to a cabin far off in the country to approximate something natural. But even there you would be breathing air that contained pollution blown in from thousands of miles away.
It seems that the earth, having been pushed too far, for too long, by too many people, has finally had enough. With record-setting high temperatures, rising seas, mass extinctions of wildlife, and fertile land turning into desert, Mother Nature is having a vigorous response to the environmental assaults humankind has delivered. You could say, in fact, that Mother Nature is having a vast allergic reaction. It has turned the world into a more chaotic place with direct implications for our health.
Air Pollution Gives Rise to Asthma and Allergies
Our health problems didn’t come out of the blue. Instead, they came from the increasingly polluted skies. A review article by Dr. Gennaro D’Amato, professor of respiratory medicine and respiratory allergy at the University of Naples, in Italy, titled “Effects of climatic changes and urban air pollution on the rising trends of respiratory allergy and asthma,” lays the scientific groundwork for this critically important area.11 Based on work done by the European Academy of Allergy and Clinical Immunology, the European Respiratory Society, and the World Allergy Organization, Professor D’Amato’s masterful review explains the connections between climate change, air pollution, allergy, and respiratory diseases.
The review tells us that rhinitis and asthma have increased over the past several decades. Studies have sought to understand what is causing the increase, and indoor and outdoor air pollution, as well as climate change, have been blamed. Much attention and research have focused on the negative impacts of air pollution on respiratory health. For those with allergies, air pollution dials up the airway response to allergens. Air pollution also makes asthma worse, causing greater bronchial hyperresponsiveness, greater use of medication, more hospital admissions, and more visits to the emergency room.12
A recent review by researchers from the Johns Hopkins University School of Medicine, Imperial College London, and the National Health Research Institutes of Taiwan sought to find out just how air pollution is leading to asthma and allergies. The researchers point out that increasing rates of allergic diseases could be directly caused by air pollution that increases inflammation, oxidative stress, and the immune response.13
Let’s look at some major pollutants that contribute to this problem.
Particulate Matter or Soot
Particulate matter is soot and dirt that is suspended in the air. It is a major component of air pollution. Particulate matter is linked to exacerbation of allergic asthma, chronic bronchitis, respiratory diseases, cardiovascular disease, and hospital admissions. Studies have confirmed that particulate matter enters the lungs and causes inflammation, leading to cardiovascular and respiratory events.
The World Health Organization estimates that inhaling particulate matter is responsible for 500,000 deaths around the world each year.14
Diesel Exhaust
Exhaust from diesel engines, mostly from trucks and buses, accounts for up to 90 percent of the particulate matter in many cities. Many diesel vehicles are so dirty that they produce approximately 100 times more black particle soot per mile than gasoline engines do.15
Breathing diesel exhaust changes lung function; burns the eyes, nose, and throat; and causes nausea, fatigue, and headache. Long-term exposure is linked to coughing, decreased lung function, and production of sputum.16
A study from the University of California–Los Angeles School of Medicine found that diesel exhaust combined with exposure to ragweed pollen produced stronger allergic reactions in lab experiments. The researchers conclude that “this synergy between DEP [diesel exhaust particles] and natural allergen exposure is suggested as a key feature in increasing allergen-induced respiratory allergic disease.”17 Living in New York City, I can tell you that the throat-burning exhaust from diesel buses and trucks is a problem every single day.
Ozone and Smog
Ozone is the main component of smog, the visible haze that sits heavily over many major cities—including, famously, Los Angeles. Ground-level ozone is created by a chemical reaction when radiation from sunlight interacts with hydrocarbons and nitrogen dioxide from cars and other vehicles.18 A study from Yale University and the Johns Hopkins Bloomberg School of Public Health explains that ozone was first discovered in the smog of Southern California and now is a recognized air pollution problem across the United States and in many other countries.
Writing in the Journal of the American Medical Association, the Yale and Hopkins researchers point out the negative impacts of short-term exposure to ozone: increased emergency room visits and hospital admissions, decreased lung function, and exacerbation of asthma and other respiratory conditions. They explain that in the United States, more than 100 locations exceed the government’s limit on ozone, and that the high levels of ozone are a result of both the sheer number of cars and other vehicles on the road today and the high number of miles that those vehicles are driven.19
Sulphur Dioxide
Sulphur dioxide comes from burning coal and oil that are high in sulfur. Breathing in this chemical causes acute bronchoconstriction in asthmatics. This effect has been observed after periods of exposure as brief as two minutes. Sulphur dioxide has also been found to increase allergic responses to other allergens in lab studies.20
A Sizzling Earth Is Making Us Sick
Global warming may seem like a far-off problem, like when rising seas in the future leave the Statue of Liberty in New York Harbor up to her neck in water. But the consequences of rising temperatures for our health are being felt right now.
The majestic glaciers on the Rocky Mountains that provide much-needed water to millions of people in the American West are shrinking. Droughts are drying out the amazingly productive farmland of California. Massive glaciers on the world’s tallest mountain range, the Himalayas, are also retreating, putting at risk a key source of fresh water for Asia. Warming oceans, super droughts, melting glaciers, and extreme weather events like hurricanes and heat waves measure the effects of a warming world—and its real impact on our health.
We are not talking about some problem that may happen in the distant future. We have already crossed over into the danger zone, where hotter temperatures are risking our health today. People with asthma are particularly vulnerable to the worsening air quality. Those with hay fever are vulnerable to the longer and more severe pollen seasons that warmer temperatures are bringing. This is happening in North America and around the world, right now.
Climate Change Worsens Respiratory Illnesses
Since the early 1960s scientists have studied the role that global warming plays in the rising asthma rates in adults and children in a wide range of countries. Today, the serious consequences for health from global warming are a major concern of the medical and scientific communities, as the following examples show.
A study from Macquarie University, in Australia, found that a significant portion of the growing prevalence and severity of asthma is the result of man-made climate change. The Australian researchers also note the increasing rates of allergic rhinitis, hives, and atopic eczema throughout the world and reiterate that higher temperatures have been reported to make the pollen season longer.21
The European Respiratory Society is a professional organization that seeks to alleviate the suffering of respiratory disease and to promote lung health through research and medical and public education. The American Thoracic Society is a professional organization dedicated to advancing research, clinical care, and public health in respiratory disease. Both of these bodies have published papers voicing their concerns about the impact of global warming on the health of people with respiratory conditions, including asthma.
Higher ozone concentrations from global warming gases lead to more cardiovascular and respiratory events, the European paper explains. Distribution of allergens, molds, infectious diseases, and smoke from forest fires undermines health and worsens respiratory diseases. The paper states: “The key climatic change factors that could potentially influence respiratory disease are extreme temperature events (both hot and cold), changes in air pollution, flooding, damp housing, thunderstorms, changes in allergen disposition and consequent allergies, forest fires, and dust storms, the effects either being short or long term.”22
The Thoracic Society paper is titled “Global Warming: A Challenge to All American Thoracic Society Members.” It notes that billions of tons of carbon dioxide are being pumped into the atmosphere, mostly from the burning of coal to generate electricity and the burning of gasoline and diesel for transportation. It quotes the director-general of the World Health Organization, Dr. Margaret Chan, who has warned that “climate change will ride across this landscape as the fifth horseman. It will increase the power of the four horsemen that rule over war, famine, pestilence, and death.”
Building on Dr. Chan’s comments, the Thoracic Society paper notes that the fifth horseman of climate change will impact respiratory patients “through the direct effects of heat, extreme weather events, air pollution, allergic diseases, water- and food-borne infections, and vector-borne and zoonotic diseases.23
“Health is inextricably linked to climate change,” proclaims an article published in the Journal of the American Medical Association. The authors, from the Global Health Institute at the University of Wisconsin–Madison, look at the ill health effects of rising temperatures—heat stress, respiratory disorders including asthma, infectious diseases, and mental health issues such as depression and post-traumatic stress disorder—that are linked to natural disasters. They note that “substantial health and economic co-benefits could be associated with reductions in fossil fuel combustion.” The article urges health care providers to communicate the health impacts of climate change and the benefits of reducing greenhouse gases, and concludes by saying that reducing greenhouse gases must happen quickly and at a substantial level.24
The U.S. Environmental Protection Agency (EPA), in its turn, states that global warming will likely lead to more severe and longer heat waves that occur with greater frequency. The EPA explains that children, older adults, and those with medical conditions are the most vulnerable to heat waves.25 Heatstroke and dehydration caused by heat waves are dangerous and can be deadly: during the summer of 2003, a severe heat wave in Europe led to 70,000 deaths in 16 countries.26
The United States has warmed by more than 2 degrees Fahrenheit over the past 50 years, notes a report by Physicians for Social Responsibility and the National Wildlife Federation titled More Extreme Heat Waves: Global Warming’s Wake Up Call. The report states that heat waves increase the risk of asthma attacks, heart attacks, and strokes. The Chicago heat wave of 1995, when temperatures peaked at 106 degrees, was made worse by high humidity and air pollution; a total of 739 people died.27 The report urges comprehensive cuts in greenhouse gases to limit heat waves in the future and encourages a switch from burning fossil fuels to using renewable sources of energy such as solar power.
The European Respiratory Society spells out the connection between climate change and respiratory disease in no uncertain terms. With regard to the impact of climate change, it states: “The main disease areas of concern are asthma, rhinosinusitis, chronic obstructive pulmonary disease (COPD), and respiratory tract infections.”28 Let’s take a closer look at how some of these problems arise.
Higher air temperatures combine with air pollution to form ozone, which exacerbates asthma. The EPA states that warming from climate change is expected to raise the number of days with unhealthy levels of ozone at ground level. Ozone inflames and damages the lungs and exacerbates asthma.29 In the cities, the urban heat island effect, in which hot air sits above highly populated areas night and day, makes conditions for asthma even worse.
A Longer Pollen Season
Ragweed plants like the higher temperatures and higher levels of pollution that go along with global warming. Ragweed plants thrive and produce more pollen, and the pollen is even more potent than before, the EPA points out.30
Smoke from Forest Fires
Forests are particularly vulnerable to temperature variation. For example, warmer temperatures are allowing tree-eating insects to thrive at higher elevations and in more locations than ever. These insects have been chewing their way through entire forests in the western United States and Canada. The dead trees they leave behind contain resin that fuels forest fires. These enormous forest fires cause loss of life among residents and firefighters and give off thick black smoke that can travel hundreds or even thousands of miles—smoke that is directly toxic to everyone and exacerbates asthma as well.
The Rising Tide of Mold
Extreme weather events like hurricanes and floods are increasing. Warmer oceans fuel more powerful hurricanes, which not only threaten the coasts but can also leave a path of destruction far inland. Mold thrives as houses and other buildings fall victim to water damage in the wake of the storms and flooding. Damp housing is associated with cough, wheeze, and asthma.31
In the original Netflix TV series Orange Is the New Black, mold contamination is a continuing theme. In one episode, an activity room could not be used because of mold. A ceiling collapse in another episode released toxic dust and mold in the chapel room. Mold even showed up on a meal tray, growing on the food. As a recurring guest star on TV, mold has definitely entered the popular imagination.
Cutting Greenhouse Gases—What Will It Take?
The American Thoracic Society’s call for a reduction in greenhouse gases is framed as a challenge to the society’s members, but it reads like a call to action for all of us. The paper states:
Mitigation of the consequences of global warming and climate change will require dedication and prioritization by the public, governments, and professional and scientific societies, such as the American Thoracic Society (ATS). The United States emits 25% of CO2 and other greenhouse gases and has 4% of the world’s population.
The Kyoto Treaty has been ratified by all of the major nations of the world except the United States; it mandated that the United States reduce CO2 to levels 7% below 1990 levels by the time period 2008–2012. Promotion of environmentally sound policies in the energy, transportation, land development, and agriculture sectors has great potential both to mitigate climate changes and improve public health for all. To avoid the worst impacts of global warming, the United States needs to achieve an 80% reduction of greenhouse gas emissions from 1990 levels by 2050. This requires transforming our economy to one that is efficient and green compared with the present carbon-based economy.
The post-Kyoto era needs vision and political activism across the political spectrum to achieve ambitious goals of reducing CO2. In addition to advocacy for local, state, and national policies to mitigate CO2 emissions, we need to reduce our own individual and worksite carbon footprints, and educate our patients and colleagues of the public health and societal threats posed by climate change.32
An array of environmental toxins that assault our health has been implicated in the rise of allergies, explains an article in the journal Allergy, Asthma & Immunology Research. More than 100,000 new chemicals have been used in consumer products in the past few decades, and they have made their way into the environment. This wave of toxins places a tremendous burden on the environment and has disastrous consequences for our health, in particular for allergies. “Exposure to environmental toxicants,” the authors explain, “not only contributes to the increasing prevalence of asthma and allergies, it also affects disease outcomes, many of which are due to an underlying immune and inflammatory dysfunction.”33
Chemicals That Interfere with Hormones
One key group of environmental toxins that the scientists implicate in allergies and asthma is the category called endocrine disrupting chemicals (EDCs).34
EDCs, chemicals found in everyday products, have made their way into the water, food, and soil all around us. In our bodies, these chemicals mimic or interfere with female and male hormones, as well as the thyroid.35 They trigger inflammation and can be involved in immune and allergic responses.36 In addition to being a health concern for people, EDCs are a threat to wildlife. As pesticides and other materials containing EDCs have entered the environment, they have harmed fish, birds, and other wildlife.
“There is mounting concern in the scientific, environmental, private, and governmental sectors on a wide range of substances, known as endocrine disruptors, that may interfere with the normal functioning of a living organism’s hormone system,”37 the Environmental Quality website of the U.S. Fish and Wildlife Service states.
So where do all these EDCs come from? The U.S. National Institute of Environmental Health Sciences tells us that EDCs are found in products such as detergents, plastic bottles, metal food can liners, cosmetics, and toys.38 EDCs are all around us: we consume them in food and water, inhale them in dust and airborne particles, and absorb them through our skin, according to the WHO. EDCs are found in some pesticides as well, and people who are exposed to pesticides in their work commonly experience wheezing, coughing, and inflammation of the airways. The association between working with pesticides and asthma has also been demonstrated.39
Phthalates, a type of EDC, have come under particular scrutiny for their adverse health effects. One phthalate, called diethyl hexyl phthalate (DEHP), which gets into the air and hitches a ride on dust, is linked to wheezing in children.40 DEHP is used to soften plastics and is found in adhesives, coatings, resins, toys, childcare products, and cosmetics, notes the Australian Government Department of Health.41 DEHP is also found in consumer food packaging.42
In a study of more than 10,000 children, exposure to DEHP and butyl benzyl phthalate was associated with asthma, rhinitis, and eczema.43 Butyl benzyl phthalate is used in plastics, vinyl floor tile, and carpet backing, and people can be exposed when the chemical is released into the air, according to a report from the WHO.44
Another type of EDC, called alkylphenols, have been found to be active in the allergic response that could contribute to the development of asthma. Alkylphenols tend to build up in the body, raise inflammation, and contribute to or worsen allergic conditions.45
Indoor Air Pollution
It’s not only our outdoor air and water that carry harmful toxins. Science has identified a major health problem in air pollution that occurs indoors—at home, at the office, in schools, in stores, and in many other places where we spend our time.
Tobacco smoke, a highly dangerous source of toxic chemicals, is considered the main culprit in indoor air pollution. Tobacco is a public health disaster for asthma. Wheezing and asthma in children are linked to their exposure to tobacco smoke, and 40 million children are exposed to tobacco smoke each year. Passive smoking—secondhand and even thirdhand—raises the risk of wheezing and asthma for children and young people by at least 20 percent. In children admitted to the hospital for these conditions, blood and saliva tests commonly show exposure to tobacco smoke. Researchers emphasize that “stopping parents smoking is crucially important to the prevention of childhood asthma.”46
Another major source of indoor air pollution is formaldehyde, a very pervasive chemical that has been found to cause and contribute to nasal allergy, dermatitis, and asthma.47 Formaldehyde is a volatile organic compound (VOC), which means it becomes a gas at room temperature.48 Products containing VOCs release these compounds in a process called off-gassing, and this is how formaldehyde gets into the air that we breathe.
This chemical is found in a multitude of products that make their way into homes, offices, schools, retail stores—just about any indoor environment. It’s commonly used in composite wood products such as plywood and in the manufacture of fabrics, including clothing. Formaldehyde also turns up in wood floor finishes, paint, and wallpaper and in emissions from laser printers, copiers, and personal computers, the U.S. Consumer Product Safety Commission says.49 And formaldehyde is a product of combustion, so it is also generated from burning tobacco, natural gas, gasoline, and wood.50
The U.S. Consumer Product Safety Commission explains that indoor air levels of formaldehyde can change depending on temperature, humidity, ventilation, and ozone level. It notes that both higher temperatures and higher humidity tend to increase formaldehyde emissions, as do higher-pollution or “ozone action” days.51 So continued global warming signals an even more troublesome forecast for allergies and asthma due to higher formaldehyde exposure in the future.
Allergy and Asthma Linked to Formaldehyde Exposure
“Breathing formaldehyde vapour can result in irritation of nerves in the eyes and nose, which may cause burning, stinging or itching sensations, a sore throat, teary eyes, blocked sinuses, runny nose, and sneezing,” explains the Australian Government Department of Health.52
Other research focuses on an even more specific link between formaldehyde, respiratory illness, and allergy. “Increased Risk of Allergy in Children Due to Formaldehyde in Homes” is the name of a study from Monash University in Australia that looked at the impact of indoor air pollution from formaldehyde on children’s health. The researchers measured formaldehyde levels in 80 homes in Victoria, Australia, and found that glued wood products, such as particleboard, were the main source of emissions of formaldehyde, which was detected in the bedrooms, living rooms, and kitchens at much higher levels than outside.
They discovered that the children’s low-level exposure to formaldehyde was linked to increased allergic sensitization to common airborne allergens. What is more, they found that exposure to higher levels of formaldehyde was linked to more severe sensitization.53 And they noted that the rise in allergies over the past few decades has paralleled the increase in formaldehyde-emitting products used inside homes.
Another study from Australia, published in the European Respiratory Journal, focused on asthma and found that exposure to formaldehyde at home “significantly increases the risk of asthma in young children.” For the study, parents whose children had asthma as the primary diagnosis were recruited by the accident and emergency department of Princess Margaret Hospital in Perth, Western Australia. The researchers noticed a seasonal variation in formaldehyde levels, with summer bringing greater exposure to the chemical than winter.54
This reinforces a troubling trend that I have mentioned earlier: that in a warming world, higher temperatures will likely increase formaldehyde levels. The researchers state that children exposed to formaldehyde at levels of “49 parts per billion (ppb) are 39% more likely to have asthma compared to those who are not exposed to such levels.”55 Comparable results were obtained by researchers at the University of Arizona, who found that children in houses with formaldehyde at levels of 60 to 120 ppb had significantly greater rates of asthma and bronchitis than those with less exposure.56
Conclusion
In this chapter I have explored the big-picture reasons behind the allergy epidemic that is sweeping the world. In order to answer the question Why are we so sick? I’ve outlined reasons that are so fundamental to our well-being that they determine in large measure whether or not we can be healthy.
Leading health organizations and medical centers around the world have documented that a multitude of factors—widespread air pollution, global warming, longer pollen seasons, tobacco smoke, toxic chemicals, dust, fast food, processed food such as trans fats and refined carbohydrates and sugar, and an out-of-balance internal ecology of microbes—are all contributing to the rise of allergies.
Is it any wonder that people are getting sick from polluted air when the number of vehicles on earth is nearing two billion, virtually all of them belching toxic chemicals into the air? We’ll come back to the subject of toxins later in the book, when I send you on a mission to root them out and reduce their impact in your personal environment.
To address these challenges, a community effort is needed, and that is why I urge you to bring this book with you to see your doctor, so we can all work together to heal ourselves and the planet. In the next chapter I’ll take a closer look at how allergy affects our bodies—particularly our immune systems—and why it makes us so sick.