The ‘Air quality and health in cities’ report, which used data from 2010 to 2019, found that global patterns of exposure to the two main air pollutants are strikingly different. “While exposure to PM2.5 pollution tends to be higher in cities located in low- and middle-income countries, exposure to nitrogen dioxide, or NO2, is high in cities in high- and low- and middle-income countries. income, “he said.
The report, published in Boston, provides a comprehensive and detailed analysis of air pollution and global health effects for more than 7,000 cities around the world, focusing on two of the most harmful pollutants: PM2.5 and NO2. In 2019, 1.7 million deaths related to PM2.5 exposure occurred in 7,239 cities, with cities in Asia, Africa, and Eastern and Central Europe having the largest health impacts. Previous reports from the higher education institution had found that air pollution is responsible for one in nine deaths, accounting for 6.7 million deaths worldwide in 2019, with a particularly strong impact on young people, the elderly and those with chronic respiratory and heart diseases.
Delhi, Calcutta, Kano (Nigeria), Lima (Peru), Dhaka (Bangladesh), Jakarta (Indonesia), Lagos (Nigeria), Karachi (Pakistan), Beijing (China) and Accra (Ghana) are among the top 10 most polluted cities due to exposure to PM2.5 while Shanghai, Moscow, Tehran (Iran), St. Petersburg (Russia), Beijing (China), Cairo (Egypt), Ashgabat (Turkmenistan), Minsk (Belarus), Istanbul (Turkey) and Ho Chi Minh City (Viet Nam) are the most polluted cities due to NO2 exposure. Beijing was on both top 10 lists.
“With the rapid growth of cities around the world, the impact of air pollution on residents’ health is also expected to increase, underscoring the importance of early action to reduce exposures and protect public health,” he said. Pallavi trouserssenior scientist from the higher education institution who oversaw the publication of the report.
Noting that up to 68% of the world’s population is expected to live in urban areas by 2050, the report states: “This rapid urbanization places the world’s major cities at the forefront of the battle to reduce the health effects of air pollution, in particular. in low- and middle-income countries “.
The report, however, also highlights data gaps in low- and middle-income nations, a key aspect of understanding and addressing the health effects of air pollution. According to the WHO’s air quality database, only 117 nations currently have ground-level monitoring systems to track PM2.5 and only 74 nations are monitoring NO2 levels.
The report that combined ground air quality data with satellites and models to produce air quality estimates for cities around the world suggested that strategic investments in air quality monitoring systems a ground level and the extensive use of satellites and other emerging technologies in the affected regions can provide the first fundamental steps towards cleaner air.
“Since most cities around the world do not have ground air quality monitoring, estimates of particulate and gas pollution levels can be used to plan air quality management approaches that ensure that the air is clean and safe to breathe, “he said Susan Anenberg of George Washington University, one of the collaborators on the project.
NO2 comes mainly from the burning of fuels often in older vehicles, power plants, industrial plants, and residential kitchens and heaters. The report notes that because city residents tend to live closer to busy roads with dense traffic, they are often exposed to more NO2 pollution than rural residents. In 2019, 86% of the more than 7,000 cities included in this report passed the WHO guideline of 10 µg / m3 for NO2, impacting approximately 2.6 billion people.
“Although PM2.5 pollution tends to draw more attention to known hotspots around the world, less data has been available for NO2 on this global scale,” the report said.