Breathing clean air is a right that should be enjoyed by every person on Earth, but as industry, agriculture and other sources of air pollution have proliferated, clean air has become increasingly scarce.
The problem has grown to monumental levels, such that the World Health Organization (WHO), in their latest report on air pollution and child health, stated, “Exposure to air pollution is an overlooked health emergency for children around the world.”1
Worldwide, the report states, 93 percent of children live in areas with air pollution at levels above WHO guidelines. Further, more than 1 in 4 deaths among children under 5 years is related to environmental risks, including air pollution. In 2016, ambient (outside) and household air pollution contributed to respiratory tract infections that led to 543,000 deaths in children under 5.
“Polluted air is poisoning millions of children and ruining their lives,” Tedros Adhanom Ghebreyesus, WHO director-general, said in a news release. “This is inexcusable. Every child should be able to breathe clean air so they can grow and fulfil their full potential.”2
Where Are Children Most at Risk?
Children are exposed to polluted air both indoors and out. Outside, ambient air pollution comes primarily from the combustion of fossil fuel, waste incineration, industrial and agricultural practices and natural disasters such as wildfires, dust storms and volcanic eruptions.
In 2016, ambient air pollution led to 4.2 million premature deaths, nearly 300,000 of which occurred in children under the age of 5 years. Exposure to air pollution occurs in developed countries — especially in low-income communities — however, children living in low- and middle-income countries (LMICs) were most affected.
Fine particulate matter (PM 2.5) refers to dust, dirt, soot and smoke — particles smaller than 2.5 micrometers in diameter. It’s the most studied type of air pollution, and the WHO report revealed that in LMICs, 98 percent of children under 5 years are exposed to fine particulate matter at levels higher than the WHO air quality guidelines.
In some areas, like African and Eastern Mediterranean regions, 100 percent of children under 5 are affected. In contrast, 52 percent of children under 5 in HICs are exposed to potentially dangerous levels of ambient air pollution. Indoors, 41 percent of the world’s population is exposed to household air pollution, particularly from cooking with polluting fuels and technologies.
WHO: Children Particularly at Risk From Polluted Air
Children are more vulnerable to the effects of air pollution than adults, in part because their bodies (including their lungs and brains) are still developing, putting them at risk from inflammation and other health damage from pollutants. They also have a longer life expectancy, giving more time for diseases to emerge.
Overall, a combination of “behavioral, environmental and physiological factors” makes children particularly susceptible to air pollution, WHO notes, adding:3
“[Children] breathe faster than adults, taking in more air and, with it, more pollutants. Children live closer to the ground, where some pollutants reach peak concentrations. They may spend much time outside, playing and engaging in physical activity in potentially polluted air.
Newborn and infant children, meanwhile, spend most of their time indoors, where they are more susceptible to household air pollution, as they are near their mothers while the latter cook with polluting fuels and devices … In the womb, they are vulnerable to their mothers’ exposure to pollutants. Exposure before conception can also impose latent risks on the fetus.”
The WHO report analyzed studies published within the past 10 years, and used input from dozens of experts, to reveal some of the top health risks air pollution poses to children. Among them:4
Adverse birth outcomes, including low birth weight, premature birth, stillbirth and infants born small for gestational age.
Infant mortality — As pollution levels increase, so does risk of infant mortality.
Neurodevelopment — Exposure to air pollution may lead to lower cognitive test outcomes, negatively affect children’s mental and motor development and may influence the development of autism and attention deficit hyperactivity disorder.
Lung function — Prenatal exposure to air pollution is associated with impaired lung development and lung function in childhood.
Acute lower respiratory infection, including pneumonia
Asthma — Exposure to ambient air pollution increases the risk of asthma and exacerbates symptoms of childhood asthma.
Childhood cancers, including retinoblastomas and leukemia
Health problems in adulthood — evidence suggests that prenatal exposure to air pollution may increase the risk of chronic lung disease and cardiovascular disease later in life.
Surprising Sources of Air Pollution
Pollution is only worsening in many parts of the world, and without aggressive intervention, deaths due to ambient air pollution could increase by more than 50 percent by 2050.5
The majority of global airborne particulate pollution — 85 percent — comes from fuel combustion, with coal being the “world’s most polluting fossil fuel.”6 Even in the U.S., an estimated 200,000 premature deaths are caused by combustion emissions, including that from vehicles and power generation.7
In a study of electric power generation in the U.S., which is coal-intensive, a study published in the journal Energy revealed that switching to natural gas for electricity generation could lead to significant benefits, including reducing sulfur dioxide emissions by more than 90 percent and nitrogen oxide emissions by more than 60 percent.8
In a Lancet study, authors took it a step further, noting that an even better solution would be shifting to low-polluting renewable energy sources such as wind, tidal, geothermal and solar options.9
The WHO authors also called for urgent changes to reduce air pollution, including switching to clean cooking and heating fuels and technologies and promoting the use of cleaner transport, energy-efficient housing and urban planning. They also advocate for improving waste management and locating schools away from busy roadways and factories.10
Industrial Agriculture’s Contribution to Air Pollution
WHO’s guidelines, as well as their estimates of how many people are breathing polluted air, do not account for ozone or nitrogen oxides, which are also known air pollutants.
Emissions of nitrogen oxides combine with oxygen and sunlight to break down into ozone. Levels of this air pollutant have tripled since 1990,11 possibly due to synthetic nitrogen-based fertilizers, which release nitrogen oxides into the atmosphere.
Researchers have long known soil microbes convert nitrogen-based fertilizers to nitrogen oxides and release them into the air. However, it was estimated that only 1 kilogram of gas was produced per 100 kilograms of fertilizer, or roughly 1 percent. Researchers thought the amount of gas would increase linearly, or stay at 1 percent of the amount of fertilizer used.
However, further experimentation found the increase was exponential and not linear, as the original research didn’t account for conversion when excess nitrogen fertilizer was applied to the fields. In California, agricultural lands may be responsible for as much as 51 percent of nitrogen oxides off-gassing across the state, especially in areas that use synthetic nitrogen-based fertilizers.12
Research published in the journal Geophysical Research Letters has also demonstrated that in certain densely populated areas, emissions from farming far outweigh other sources of particulate matter air pollution.13 As nitrogen fertilizers break down into their component parts, ammonia is released into the air.
Ammonia is one of the byproducts of fertilizer and animal waste. When the ammonia in the atmosphere reaches industrial areas, it combines with pollution from diesel and petroleum combustion, creating microparticles. Concentrated animal feeding operation (CAFO) workers and neighboring residents alike report higher incidence of asthma, headaches, eye irritation and nausea.14
Air Pollution Is Becoming More Dangerous Than Ever
Pollution is the “largest environmental cause of disease and premature death in the world today,” according to research published in The Lancet.15 The study revealed that 9 million premature deaths were caused by pollution in 2015, which is 16 percent of deaths worldwide. What’s more, among the pollution-related deaths, the majority — 6.5 million — were caused by airborne contaminants.
Fine particulate matter can enter your system and cause chronic inflammation, which in turn increases your risk of a number of health problems, from cancer to heart and lung disease. In the case of heart disease, fine particulate air pollution may increase your risk by inducing atherosclerosis, increasing oxidative stress and increasing insulin resistance, the researchers noted, adding:16
“The strongest causal associations are seen between PM 2.5 pollution and cardiovascular and pulmonary disease. Specific causal associations have been established between PM 2.5 pollution and myocardial infarction, hypertension, congestive heart failure, arrhythmias and cardiovascular mortality.
Causal associations have also been established between PM 2.5 pollution and chronic obstructive pulmonary disease and lung cancer. The International Agency for Research on Cancer has reported that airborne particulate matter and ambient air pollution are proven group 1 human carcinogens.”
Using Your Diet to Protect Against Air Pollution
Because you can’t always control your exposure to air pollution, especially that outdoors, one of the best options is to fortify your diet with nutrients that may have a protective effect against pollutants. This includes:17
• Omega-3 fats — They’re anti-inflammatory, and in a study of 29 middle-aged people, taking an animal-based omega-3 fat supplement reduced some of the adverse effects to heart health and lipid levels, including triglycerides, that occurred with exposure to air pollution (olive oil did not have the same effect).18
• Broccoli sprouts — Broccoli-sprout extract was shown to prevent the allergic nasal response that occurs upon exposure to particles in diesel exhaust, such that the researchers suggested broccoli or broccoli sprouts could have a protective effect on air pollution’s role in allergic disease and asthma.19
A broccoli-sprout beverage even enhanced the detoxification of some airborne pollutants among residents of a highly polluted region of China.20
• Vitamins C and E — Among children with asthma, antioxidant supplementation including vitamins C and E helped to buffer the impact of ozone exposure on their small airways.21
• B vitamins — A small-scale human trial found high doses of vitamins B6, B9 and B12 in combination completely offset damage caused by very fine particulate matter in air pollution.22
Four weeks of high-dose supplementation reduced genetic damage in 10 gene locations by 28 to 76 percent, protected mitochondrial DNA from the harmful effects of pollution, and even helped repair some of the genetic damage.
Stopping Air Pollution Will Take a Global Effort
In many areas of the world, people have limited options to improve air quality both inside and outside of their homes. WHO recommends the use of clean stoves for cooking as a key way to improve household air pollution, but notes that “reducing ambient air pollution requires wider action, as individual protective measures are not only insufficient, but are neither sustainable nor equitable.”23
Solving the problem, and protecting the health of future generations of children, will instead take a global effort. According to WHO:24
“To reduce and prevent exposure to both household air pollution and ambient air pollution, public policy is essential. Air pollutants do not recognize political borders but travel wherever the wind and prevailing weather patterns take them. Therefore, regional and international cooperative approaches are necessary to achieve meaningful reductions in children’s exposure.
Approaches to preventing exposure must be complementary and mutually reinforcing, on every scale: houses, clinics, health care institutions, municipalities, national governments and the global community …
Individual efforts can add up to collective action that changes minds, changes policies and changes the quality of the air around us. Such actions would go far toward ensuring that children can breathe freely, without the terrible burdens imposed by air pollution.”
In your own home, I recommend taking steps to keep your indoor air clean, including opening windows to let fresh air in and avoiding the use of known air pollutants like chemical cleaning products, air fresheners and scented candles. Purifying your home’s air is also a wise step, but no one filter can remove all pollutants, so be sure to do your research on the different types of air filters to meet your specific needs.