Air pollution is a major environmental risk to health, especially for infants and children. In addition to outdoor air pollution, indoor smoke is a serious health risk for some 3 billion people who cook and heat their homes with biomass and fossil fuels. In October 2018, the World Health Organization released a special report summarizing the latest scientific knowledge on the linkages between exposure to air pollution and adverse health effects in children. The following is a compilation of the key figures and major findings of the WHO report.
Statistical figures related to air pollution and children:
- In 2016, 91% of the world population was living in places where the WHO air quality guidelines levels were not met.
- Every day around 93% of the world’s children under the age of 15 years (1.8 billion children) breathe air that is polluted.
- Globally, one in every eight deaths, or a total of 7 million deaths, was attributable to the joint effects of ambient air pollution and household air pollution in 2016.
- Of the total deaths attributable to the joint effects of household air pollution and ambient air pollution worldwide in 2016, more than 9% were in children.
- Ambient (outdoor) air pollution in both cities and rural areas was estimated to cause 4.2 million premature deaths worldwide in 2016.
- Some 91% of those premature deaths occurred in low- and middle-income countries, and the greatest number in South-East Asia and Western Pacific regions.
- Globally, 93% of all children under 5 years (about 630 million in total) in the world exposed to levels of fine particulate matter (PM2.5) higher than the WHO air quality guideline levels;
- In low- and middle-income countries, 98% of all children under 5 years exposed to levels of fine particulate matter (PM2.5) higher than the WHO air quality guideline levels;
- In African and Eastern Mediterranean regions, 100% of all children under 5 years exposed to levels of PM2.5 higher than the WHO air quality guideline levels;
- Some 543 000 deaths in children under 5 years and 52 000 deaths in children aged 5–15 years were attributed to the joint effects of ambient and household air pollution in 2016.
Effects of air pollution on child health
According to the WHO’s report, a growing body of evidence has shown significant associations between exposure to air pollution and adverse outcomes in children, as listed in the following:
- Exposure to air pollution, particularly PM2.5, is associated with low birth weight, preterm birth, and high risk of infant mortality.
- Both prenatal and postnatal exposure to air pollutants can negatively affect neurodevelopment, resulting in lower cognitive test outcomes and the development of behavioural disorders such as autism spectrum and attention deficit hyperactivity disorders.
- Both prenatal and postnatal exposure to air pollutants is associated with impairment of lung development and lung function in childhood.
- Exposure to air pollutants increase the risk of pneumonia and other respiratory infections in young children.
- Household air pollution is the leading cause of acute lower respiratory infection in children under 5 years.
- Exposure to air pollutants is associated with the development and exacerbation of childhood asthma.
- Exposure to air pollutants may increase the risk of otitis media in children.
- Both prenatal and postnatal exposure to air pollution is associated with higher risks of retinoblastoma and leukaemia in children.
- Exposure to air pollution early in life can impair lung development, reduce lung function and raise the risk of chronic lung disease in adulthood.
- Exposure to air pollution during pregnancy can predispose the offspring to cardiovascular disease later in life.