Pollution's Deadly Impact: Killing Humans Silently

Pollution is the single biggest environmental threat to human health, killing an estimated nine million people prematurely each year. According to the World Health Organization (WHO), 99% of the global population breathes air that exceeds its guideline limits. Air pollution is linked to a range of serious health issues, including cardiovascular disease, cancer, tissue damage, asthma, and other respiratory ailments. It also has severe economic impacts, causing a loss of 6.1% of global economic output in 2019. While air pollution is the most pressing concern, chemical pollution from sources such as lead, pesticides, and mercury also contributes to significant health risks and deaths. The effects of pollution disproportionately impact low- and middle-income countries, as well as vulnerable populations such as children, older individuals, and those with pre-existing health conditions. Addressing pollution is crucial not only for human health but also for mitigating climate change and ensuring the sustainability of modern societies.

Fossil fuel air pollution kills one in five people

Air pollution is an "invisible killer", according to Neelu Tummala, an ear, nose, and throat physician at George Washington University School of Medicine and Health Sciences. The air we breathe impacts everyone's health, but particularly children, older people, those on low incomes, and people of colour. People in urban areas are usually the worst affected.

A new study has found that air pollution from fossil fuels kills one in five people worldwide. The research, published in Environmental Research, puts the global death toll at about 8.7 million in 2018, more than twice that of previous estimates. The study was conducted by a team from Harvard University, the University of Birmingham, the University of Leicester, and University College London.

According to the research, exposure to fine particulate matter, or PM 2.5, from burning fossil fuels was responsible for about 8.7 million deaths globally in 2018. That’s roughly the same number of people living in New York City or London. To put this health crisis into perspective, fossil fuel pollution kills more people each year than HIV, tuberculosis, and malaria combined.

PM 2.5 is any airborne particle that is up to 2.5 microns in diameter—about one-thirtieth of the width of a human hair. These particles are problematic because they linger in the air, are easily inhaled, and can penetrate deep into the lungs, where they can enter the bloodstream and damage multiple organs. Links between this type of pollution and serious health problems such as cardiovascular disease, cancer, tissue damage, and asthma and other respiratory ailments are well documented.

The health gains from moving away from fossil fuels are twice what was previously thought, according to Dr Aaron Bernstein, Director of the Center for Climate, Health, and the Global Environment at Harvard Chan School. "Now more than ever we can see the healthier, more just and sustainable world that climate actions can deliver," he said.

Air pollution disproportionately affects low-income countries

Air pollution is an invisible killer, and it disproportionately affects low-income countries and communities. It is one of the leading causes of death worldwide, with one in five people dying due to air pollution from fossil fuels. While air pollution harms everyone, people from low-income communities are at a higher risk of adverse health effects and premature death. This disparity is evident within countries, especially in the United States, and also between countries, with low- and middle-income countries bearing a greater burden.

Several factors contribute to the disproportionate impact of air pollution on low-income countries and communities. Firstly, industrial plants, transport corridors, and other pollution sources are often disproportionately placed in low-income neighbourhoods. This results in higher levels of air pollution in these areas, reinforcing their status as low-income neighbourhoods. Additionally, low-income groups tend to depend more on outdoor physical labour jobs, increasing their exposure to air pollution.

Secondly, socioeconomic inequalities play a significant role. Ethnic minorities and low-income populations in the United States, for example, are often exposed to higher pollution levels due to decades of residential segregation. Higher-income Black individuals still face greater health risks than lower-income whites due to factors such as chronic stress from discrimination. Moreover, low-income countries and communities often have less developed healthcare systems, limited access to adequate and affordable healthcare, and face constraints on healthcare availability, further increasing mortality rates related to air pollution.

The interplay between pollution, exposure, and poverty highlights the vulnerability of low-income populations. Studies have found a positive correlation between areas with higher unemployment rates, higher use of public transportation, lower home values, and lower median incomes, and increased health risks from air pollution. This disparity is further exacerbated by the lack of stringent air quality regulations, the use of older and more polluting machinery and vehicles, fossil fuel subsidies, congested urban transport, and rapidly developing industrial sectors in low-income countries.

Addressing air pollution and reducing emissions can have significant health and economic benefits. For instance, China's efforts to lower PM 2.5 emissions from fossil fuels resulted in a 44% reduction between 2012 and 2018, saving around 1.5 million lives annually. Additionally, implementing targeted measures to reduce pollution intensity, such as facilitating the transition to cleaner fuels and supporting less polluting technologies, can help alleviate the disproportionate impact of air pollution on low-income countries and communities.

Air pollution is an invisible killer

Air pollution is caused by fossil fuels, smog, soot, greenhouse gases, and other airborne particles. These particles, known as PM2.5, are tiny—less than 2.5 microns in diameter, or about one-thirtieth the width of a human hair. Because of their size, they can be easily inhaled and penetrate deep into the lungs, entering the bloodstream and causing damage to multiple organs. The health risks are particularly severe for children, older individuals, those on low incomes, and people of colour, especially those in urban areas.

The World Health Organization (WHO) has stated that 99% of the global population breathes air that exceeds its guideline limits, with low- and middle-income countries suffering the highest exposures. In these countries, 94% of air pollution deaths occur, largely due to noncommunicable diseases such as cardiovascular disease, stroke, chronic obstructive pulmonary disease, and lung cancer. The economic effects of air pollution are also significant, with losses in some regions equivalent to 9.3% to 10.3% of GDP.

Despite the dangers of air pollution, the necessary steps to address the issue have not been taken. While there has been growing attention to pollution in the research community, with initiatives such as the European Human Exposome Network and the Superfund Research Program, the global goal of sound chemicals and waste management has not been achieved. Many of the thousands of manufactured chemicals in commerce have not been adequately tested for safety or toxicity, and the true disease burden of these chemicals is unknown.

It is important to recognize that air pollution is a global issue that affects everyone, and that addressing it can help mitigate climate change and improve human well-being.

Chemical pollution and lead poisoning contribute to deaths

Pollution is an existential threat to human health and planetary health, and jeopardises the sustainability of modern societies. Chemical pollution and lead poisoning are major contributors to deaths globally.

Firstly, chemical pollution is a growing peril and a potential catastrophic risk to humanity. There are thousands of manufactured chemicals in commerce, yet only a small fraction of these have been adequately tested for safety or toxicity. The undercounting of the disease burden attributable to chemical pollution is substantial, and the consequences are worrying. Three particularly concerning and inadequately charted consequences of chemical pollution are developmental neurotoxicity, reproductive toxicity, and immunotoxicity. Over 200 chemicals, including lead, methylmercury, polychlorinated biphenyls, arsenic, organochlorine and organophosphate pesticides, organic solvents, and brominated flame retardants, are neurotoxic to humans. Many of these chemicals are widespread in the modern environment, and children are especially susceptible to their effects. Even low-dose exposures to neurotoxic chemicals during key periods of developmental vulnerability in fetal and postnatal life can have more serious health effects than high-dose exposures.

Secondly, lead poisoning is a significant contributor to deaths worldwide. Lead exposure was attributed to more than 1.5 million deaths globally in 2021, primarily due to cardiovascular effects. Lead is a toxic metal that occurs naturally in the Earth's crust, but human activities such as mining, burning fossil fuels, and manufacturing have caused it to become more widespread. Lead can build up in the body over months or years, and even small amounts can cause serious health problems. Young children are particularly vulnerable to lead poisoning as they may absorb up to 4–5 times as much lead as adults from an ingested dose. Their innate curiosity and frequent hand-to-mouth behaviours increase their risk of exposure to lead-contaminated dust, soil, and paint. Lead-based paint and lead-contaminated dust in older buildings are common sources of lead poisoning in children. Other sources include contaminated air, water, and soil. Adults who work in certain industries, such as auto repair, construction, and battery manufacturing, may also be exposed to lead. Lead exposure can have serious health consequences, including damage to the brain and central nervous system, causing coma, convulsions, and even death.

Overall, chemical pollution and lead poisoning pose significant risks to human health and contribute to deaths worldwide. More research, regulation, and awareness are needed to address these issues effectively and minimise their adverse effects on human health and the environment.

Air pollution is the largest existential threat to humans

Air pollution is the leading cause of premature deaths worldwide, with an estimated 9 million people dying prematurely each year due to pollution. This accounts for about one in five people, with the majority of these deaths occurring in low- and middle-income countries. According to the World Health Organization (WHO), 99% of the global population breathes air that exceeds safe limits, and air pollution impacts the health of many more people than just those who die prematurely.

Outdoor air pollution, typically emitted by vehicles and industrial sources like power plants and factories, is the most significant contributor to pollution-related deaths, causing 6.5 million deaths each year. This number has increased by about 55% since the year 2000, with 4.5 million deaths attributed to ambient air pollution in 2019. The increase in deaths due to industrialization and urbanization is concerning, with a 7% rise since 2015 and a 66% increase since 2000.

Household air pollution, water pollution, and lead pollution also contribute significantly to premature deaths, with 1.2 million, 1.3 million, and 900,000 deaths attributed to these sources, respectively. Lead poisoning and other chemical pollutants, such as pesticides, mercury, and asbestos, are likely responsible for about 1.8 million deaths, but this number is likely an underestimate as the full health impacts of many chemicals are unknown or inadequately charted.

The effects of air pollution are not limited to physical health; it also has economic implications. In 2019, the global economic losses attributable to household and ambient air pollution amounted to 6.1% of global economic output. The economic impact is particularly severe in regions of East Asia and the Pacific, where losses are equivalent to 9.3% of GDP, and in South Asia, where losses reach 10.3% of GDP.

Despite the well-documented health and economic effects of air pollution, the issue has largely been overlooked in international development agendas, with minimal increases in attention and funding since 2015. However, there have been some positive developments, such as the launch of the Alliance for Clean Air during COP26, which brings together business leaders committed to reducing air pollutant emissions and championing the social, economic, and climate benefits of tackling air pollution.

Air pollution is a serious threat to human health and well-being, and its impact is only growing as society becomes increasingly industrialized and urbanized. Addressing air pollution is crucial not only for the health of people worldwide but also for mitigating climate change and ensuring the sustainability of modern societies.

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