Air Pollution: Which Continent Suffers The Most?

Air pollution is a significant issue affecting many countries and continents, with Asia being the continent that consistently ranks the highest in air pollution. A recent report listed the top 20 most polluted cities, with 19 of them located in Asia. India, in particular, stands out, with its capital, New Delhi, ranked as the world's most polluted capital for six consecutive years. However, other continents, such as Africa, are also facing air pollution challenges, with countries like Chad, Uganda, and Rwanda struggling with poor air quality.

Chad has the worst air pollution in the world, with a PM2.5 concentration of 91.8 in 2024

Chad, a country in north-central Africa, has the worst air pollution in the world, with a recorded PM2.5 concentration of 91.8 in 2024—a figure that far exceeds the World Health Organization's (WHO) recommended safe level of 5µg/m3. Chad's capital, N'Djamena, is the second most polluted capital in the world, with an annual average PM2.5 concentration of over 90µg/m3. The city frequently grapples with dust storms, and the country's increasing reliance on biomass as a primary energy source for cooking and heating continues to raise indoor pollution, with dire health implications.

Chad's poor air quality is driven by several factors, including desert dust, vehicle emissions, and biomass burning. The country's air pollution has severe health consequences for its population, particularly vulnerable groups such as children and women. According to IQAir, a Swiss air quality monitoring firm, Chad and Bangladesh were the world's most polluted countries in 2024, with average smog levels more than 15 times higher than WHO guidelines.

Air pollution is a critical global health issue, contributing to various health problems, including breathing issues, the worsening of asthma, and even congenital disabilities. It can affect nearly every organ and system in the human body and is responsible for a significant number of premature deaths each year. According to the Lancet, air pollution caused nearly 4.5 million premature deaths in 2019, while the WHO estimates that it causes 7 million premature deaths annually.

While the data on air pollution is concerning, it is important to note that there are significant data gaps, especially in Asia and Africa. Many developing countries have relied on air quality sensors mounted on US embassy and consulate buildings to track their smog levels. However, the State Department has recently ended this scheme due to budget constraints, impacting the availability of real-time data in Africa.

Bangladesh's air quality has improved but remains poor, with a PM2.5 of 65.8 in 2022

Air pollution is a pressing issue that significantly impacts the health and well-being of populations worldwide. According to the World Health Organization (WHO), air pollution causes approximately 7 million premature deaths annually, contributing to about 10% of all deaths globally. In 2022, Bangladesh made some progress in improving its air quality, but it still ranks among the worst globally. The country's PM2.5 concentration decreased to 65.8 in 2022 from 76.9 in 2021 and 97.1 in 2018, which was the world's highest.

Bangladesh's air quality improvement efforts are overshadowed by the persistent poor air quality in Dhaka, the capital city, and other urban areas. The country's largest source of air pollution is its brickmaking industry, which employs one million people and produces 23 billion bricks annually. The extensive use of brick kilns, vehicular emissions, factory fumes, and dust accumulation contribute significantly to Bangladesh's air pollution crisis. These sources release pollutants such as carbon monoxide, ozone, nitrogen dioxide, sulfur dioxide, furans, dioxins, lead, mercury, and fine particulate matter (PM2.5).

The health risks associated with air pollution in Bangladesh are severe. According to the Air Quality Life Index (AQLI), the average Bangladeshi resident's life expectancy is shortened by 6.8 years due to fine particulate air pollution (PM2.5), relative to the WHO guideline of 5 µg/m³. In Gazipur, the country's most polluted district near Dhaka, air pollution reduces life expectancy by 8.3 years. Pregnant mothers are also highly vulnerable, with pollution increasing the risks of miscarriage, stillbirth, and infants being born underweight or prematurely.

Bangladesh's pollution concentration is far above the country's national standard of 15 µg/m³. If the country could meet this standard, it would add 5.8 years to the average citizen's life. Improving air quality data accessibility and timeliness could empower Bangladeshi citizens to address air pollution more effectively. While Bangladesh's air quality has shown some improvement, the country still has a long way to go to ensure a healthier and safer environment for its population.

Regarding the continent with the worst air pollution, it is challenging to determine a single continent as air pollution varies across countries and regions. However, Central and South Asia, including countries like India, Pakistan, and Bangladesh, often face severe air pollution due to industrial growth, traffic congestion, and dust storms. In 2022, Lahore in Pakistan had the worst air quality among cities globally, with a PM2.5 level of 97.4.

India has many cities with poor air quality, including Delhi

India has 21 of the world's 30 cities with the worst air pollution, including New Delhi, the capital city with the poorest air quality globally. Thirteen of the 25 cities worldwide with the highest levels of PM are in India. Gwalior, the city with the worst air quality in India, recorded PM10 and PM2.5 levels of 329 μg/m3 and 144 μg/m3, respectively. In comparison, London's PM10 and PM2.5 levels were 22 μg/m3 and 16 μg/m3, respectively.

Delhi's poor air quality has been likened to a "gas chamber" by the city's chief minister. An average PM2.5 level of 226 μg/m3 was recorded in Delhi in December 2015, compared to 95 in Beijing during the same period. Delhi's air is twice as polluted as Beijing's. In November 2017, monitoring stations in the city recorded an air quality index of 999, comparable to smoking 45 to 50 cigarettes daily.

The primary sources of air pollution in Delhi are power plants, stubble burning, lit garbage, road dust, factories, and vehicles. The Badarpur Thermal Power Station, a coal-fired power plant, was a major contributor to Delhi's air pollution until its permanent shutdown in October 2018. Motor vehicle emissions have been found to be significantly higher in real-world conditions than in laboratory tests. The practice of burning crop stubble after harvest to prepare for the next season's planting is another significant factor, accounting for 32% of Delhi's PM2.5 particulate matter.

The consequences of poor air quality in India are dire, with over 2 million deaths attributed to air pollution annually. It causes respiratory and cardiovascular diseases and has been linked to congenital disabilities, worsening asthma, and other health issues. In Delhi alone, 2.2 million children have irreversible lung damage due to air pollution.

Recognizing the severity of the problem, the Indian government launched the National Clean Air Program (NCAP) in 2019 to reduce air pollution by 20-30% by 2024 in over 122 severely affected cities. Actions are being taken in several cities, including implementing health risk communication plans, increasing monitoring stations, and improving control of industrial emissions. Public awareness of air pollution as a pressing issue is growing, with 85% of Delhi residents supporting stricter air quality laws and enforcement.

Air pollution is a significant health risk, contributing to 4.5 million premature deaths in 2019

Air pollution is a pressing global health issue, with far-reaching implications. According to The Lancet, air pollution contributed to an estimated 4.5 million premature deaths in 2019. This figure underscores the immense danger posed by polluted air, highlighting the urgency of addressing this issue.

The World Health Organization (WHO) provides global guidance on air quality, offering threshold recommendations for key pollutants. Unfortunately, 91-99% of the world's population lives in areas where air quality falls short of these guidelines. This alarming statistic underscores the widespread nature of the problem.

The health consequences of air pollution are dire and wide-ranging. Polluted air can affect nearly every organ and system in the human body. It is linked to respiratory issues, including asthma and chronic obstructive pulmonary disease (COPD), as well as congenital disabilities. Fine particulate matter, specifically PM2.5, is of particular concern. These particles are small enough to remain in the lungs and enter the bloodstream, increasing the risk of non-communicable diseases such as heart disease, stroke, diabetes, and lung cancer. In 2021, PM2.5 air pollution was attributed to 7.8 million deaths globally, underscoring its deadly impact.

Outdoor air pollution, caused by factors such as traffic, industrial activities, and power plants, disproportionately affects people in low- and middle-income countries. In 2019, 89% of premature deaths due to outdoor air pollution occurred in these regions, with the greatest burden in the WHO South-East Asia and Western Pacific Regions. This disparity highlights the need for global cooperation to address this issue.

Additionally, indoor air pollution, often caused by the combustion of polluting fuels for cooking and heating, poses a significant health risk. This is especially true in regions like Africa and Asia, where indoor air pollution contributed to 500,000 child deaths in 2021. Furthermore, children under five are uniquely vulnerable to air pollution, with potential health effects lasting a lifetime. Exposure to air pollution during pregnancy can lead to premature birth and low birth weight, while young children may develop pneumonia, asthma, or other respiratory issues.

In conclusion, air pollution is an urgent global health crisis, contributing to millions of premature deaths annually. The impact of air pollution falls disproportionately on vulnerable populations, including children and those in low- and middle-income countries. Addressing this issue requires concerted efforts to improve air quality, protect vulnerable groups, and implement policies supporting cleaner energy, transportation, and industry practices.

Lahore, Pakistan, leads the 2024 rankings of cities with the worst air pollution

In 2024, Lahore, Pakistan, topped the rankings of cities with the worst air pollution. The city of 14 million residents recorded a pollution level of 1900 on the air-quality index (AQI), the highest in Pakistan's history. The concentration of PM 2.5, or tiny particulate matter, in the air approached 450, a level deemed hazardous.

Lahore's air pollution has been attributed to various factors, including vehicle fuel quality, construction, and industrial activity. The provincial government has also blamed toxic air drifting in from neighbouring India, particularly the northern regions, which are also battling severe air pollution. Lahore's proximity to the Pakistan-India border, just 25 km away, likely exacerbates the issue.

The air pollution in Lahore has had significant impacts on the health and daily lives of its residents. Tens of thousands of people, especially children and the elderly, have been affected by the toxic smog. The government has implemented a ""green lockdown,"" mandating that 50% of employees work from home and requiring everyone in Lahore to wear face masks. Primary schools have been closed for a week, and certain construction activities have been banned. Wedding halls must close by 10 pm, and there are restrictions on motorized rickshaws and barbecuing without filters.

The crisis has prompted local authorities to take further action. The Punjab Provincial Disaster Management Authority has declared smog a "calamity" and instituted emergency measures. The government has also considered using artificial rain to combat the pollution. Lahore's air pollution has not only affected the city's residents but also underscored the urgent need for improved air quality across the region.

While Lahore currently leads the rankings for 2024, it is worth noting that other cities and countries have also faced critical air pollution issues. For instance, Multan in Pakistan has seen AQI levels exceed 2,000, and cities in India, such as New Delhi, have also struggled with hazardous air quality. Additionally, countries like Chad, Iraq, and Bangladesh have been listed among the most polluted in recent years, facing challenges from dust storms, industrial growth, and brick-making industries. Addressing air pollution is a global concern, with over 90% of the world's population living in areas where air quality exceeds World Health Organization (WHO) guidelines.

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