Air quality plays a large part in the development of a healthy respiratory system. This means that the air a person breathes in during the early years of their life contributes to their lung function later. Unfortunately, air pollution is a growing problem and is a factor in about 7 million deaths across the world each year.
Data from the World Health Organization (WHO) shows that nine out of every ten people (and 93% of people under 15) breathe polluted air. In developing nations, exposure to highly contaminated air during childhood reduces a person’s lifespan by 4 to 5 years. Air pollution is to blame for approximately one-third of all deaths from heart disease, lung cancer, and stroke worldwide.
The extent of the issue
Air pollution and climate change go hand in hand. As the population of the world grows, so does the amount of resources its residents utilize; therefore, more waste products are produced, including greenhouse gases. But there are more air pollutants than just greenhouse gases. Also note that air pollution disproportionately affects people in lower- and middle-income countries (LMICs); while 98% of children in LMICs breathe in air with particulate matter levels than WHO guidelines, only 52% of children in higher-income countries do.
Particulate matter (PM) and aerosols are other common air pollutants. As defined by the Inter-governmental Panel on Climate Change (IPCC), an aerosol is “a suspension of airborne solid or liquid particles, with a typical size between a few nanometres and 10 μm that reside in the atmosphere for at least several hours.” Some PM is so small it can readily be absorbed in the bloodstream through the lungs.
A major issue with aerosols and particulate matter is that they can deposit onto surfaces all around the globe, as they are carried in the air for long distances. Their deposition contributes to climate change; deposits make ice and glaciers slightly darker, meaning they reflect less sunlight and are slightly warmer. In a similar matter, even a minute increase in temperature allows plants in polar regions to grow larger, causing the plants to cast greater shadows and also hinder reflection.
The very small nature of many pollutants translates into polluted air being difficult to avoid. Unlike an area with a cigarette smoker, people can’t usually walk away from the places they live just to breathe better air. And while smog is a definite indicator of air pollution, a lack of smog does not signal good air quality.
Levels of PM, ground-level ozone, lead, carbon monoxide, and a number of other pollutants in the United States have decreased in recent years. This is partially a result of standards enacted with the passing of the 1970 Clean Air Act. Nonetheless, it is now known that some compounds in the air are dangerous even at very low concentrations. In the past 15 years, the Environmental Protection Agency (EPA) has made air quality standards for ground-level ozone, lead, nitrogen dioxide, PM, and sulfur dioxide more stringent.
However, about half of the world’s population uses biomass (crops, dung, and wood), coal, or kerosene for energy at home, and that proportion is increasing. Raw materials are usually burnt in simple stoves in an enclosed space. Women and children especially are exposed to the resulting fumes, as they tend to spend more time indoors. Household air pollution alone kills 4 million people globally per year. Also, indoor air pollution might be responsible for about 4% of global diseases.
These two examples of air pollution situations demonstrate the two types of air pollution: ambient (outdoor) and indoor. The two are not mutually exclusive, though, and have an effect on each other, since air flows between indoors and outdoors.
Climate change in general translates to longer, warmer days, which in turn leads to longer pollen seasons. Warmer temperatures also increase levels of ozone in the atmosphere.
The impact on health
Children below the age of 5 are especially prone to negative effects from inhaling particulate matter. During the first year of life, air pollution can cause impaired growth. Inhalation of air with high levels of PM led to 400,000 infant deaths in sub-Saharan Africa in 2015. Eighty percent of deaths attributed to pneumonia occur in children under the age of two.
Exposure to air pollution before conception can have an influence on the health of a fetus, as can prenatal exposure. A significant link between outdoor air pollution and adverse birth outcomes such as low birth weight exists. Preterm birth has been especially connected to PM exposure. Birth outcomes are more affected by ozone in mothers with asthma and by particulate matter and nitrogen dioxide in mothers with diabetes.
In children, indoor air pollution exacerbates asthma and increases the risk for chronic obstructive pulmonary disease as well as acute respiratory infections. About half of all lethal pneumonia cases under the age of five are due to inhalation of PM of household origin. Indeed, the risk of a child developing pneumonia doubles once they are exposed to polluted air. Most air pollutants have a positive association with pneumonia, bronchitis, and asthma. Indoor air pollution accounts for more child deaths than does outdoor air pollution.
Respiratory infections are the leading cause of death in LMICs; worldwide, respiratory infections are the leading cause of hospital visits in children. One in every eight deaths in the world in 2016 was due to the effects of air pollution. Keep in mind that rates of air pollution-related infectious disease are higher in LMICs, especially those in sub-Saharan Africa and South and Southeast Asia.
Other than respiratory issues, air pollution can cause a number of other health problems throughout the body. Among the many conditions pollution has been linked to are cardiovascular disease, stroke, bladder cancer, dementia, diabetes mellitus, autoimmunity, osteoporosis, conjunctivitis (pink eye), inflammatory bowel disease, acne, and skin aging.
Multiple studies have also associated air pollution with overweight and obesity in children. Cognitive abilities of children, including attention and memory, are negatively impacted by prenatal air pollution. Exposure to nitrogen oxides during pregnancy has been linked to autism. Prolonged benzene exposure, especially from traffic pollution, increases a child’s risk of developing leukemia.
People exposed to air pollution early in life are more prone to health issues down the road. Exposure to air pollution as a child can permanently impair lung development, leading to respiratory issues throughout the lifespan as well as an increased risk for chronic lung diseases. Children who are repeatedly exposed to air pollution also have a higher likelihood of developing cardiovascular disease later in life.
The possible solutions
A 2018 IPCC report urges the importance of limiting global warming to 1.5℃ by 2030 to mitigate climate change. According to the WHO, if all nations met the goals of the Paris Agreement by 2050, about a million lives will be saved annually due to reduced air pollution.
Improving air quality is a part of the UN Sustainable Development Goal (SDG) on health (3) and ensuring access to clean energy is a part of the SDG on energy (7). The SDGs are “a universal call to action to … protect the planet and improve the lives and prospects of everyone, everywhere.” With an aim to achieve the goals by 2030, the SDGs were adopted by the UN in 2015. A significant part of SDG 7 is making a global switch to clean energy, including the end of the use of biomass and coal in homes.
Although individuals can make contributions towards improving air quality, such as riding a bike or bus instead of taking a car, about three-quarters of all greenhouse gases produced in the United States come from transportation, electricity, and industry. Therefore, it is imperative that corporations also work to become more sustainable in order to really improve air quality and lessen the impacts of climate change.
A novel solution to dust pollution proposed in a 2020 article calls for irrigation of a particular basin in Africa that accounts for a majority of the world’s dust emissions. This type of approach to mitigating dust pollution has already been tried successfully on a small scale in California. The cost of the measure per life saved is on par with that of a number of sanitation, vaccine, and water projects, meaning the seemingly outlandish suggestion is actually quite feasible (financially, at least).
Hopefully this article taught you something new about the importance of clean air. Be sure to share something you’ve learned with someone! Let me know if you’ve heard of any other ideas for reducing air pollution at the global level.