Executive Summary and Key Messages
Around 300 million children currently live in areas where the air is toxic – exceeding international limits by at least six times. Using satellite imagery of outdoor air pollution, this study found that around 300 million children currently live in areas where outdoor air pollution exceeds international guidelines by at least six times. In total, around 2 billion children live in areas that exceed the World Health Organization annual limit of 10 μg/m3 (the amount of micrograms of ultra-fine particulate matter per cubic metre of air that constitutes a long term hazard).
Air pollution is linked directly with diseases that kill. In 2012, air pollution was linked with 1 out of every 8 deaths, globally – or around 7 million people. Around 600,000 of those were children under 5 years old, globally. Almost one million children die from pneumonia each year, more than half of which are directly related to air pollution.
Air pollution can considerably affect children’s health. Studies have shown that air pollution is strongly associated with respiratory conditions such as pneumonia, bronchitis and asthma, among others. It can also exacerbate underlying health issues and prevent children from going to school, and there is emerging evidence that it can disrupt physical and cognitive development.
Left untreated, some health complications related to air pollution can last a lifetime. Air pollution is worsening in many parts of the world. As countries continue to industrialize and urbanize, energy, coal and fuel use tends to increase. A recent publication from the World Health Organization (WHO) indicates that urban outdoor air pollution has increased by about 8 per cent between 2008 and 2013.
Projections are unfavourable. According to the Organisation for Economic Co-operation and Development (OECD), under-five mortality could be 50 per cent higher than current estimates by 2050 as a result of outdoor air pollution. Another study published in Nature found it could be even worse – doubling by 2050.
Children are uniquely vulnerable to air pollution – due both to their physiology as well as to the type and degree of their exposure.
Air pollution can seriously affect the health of the foetus. Pregnant mothers are advised to avoid air pollution – just as they should avoid smoking or breathing secondhand cigarette smoke. Studies have shown that chronic exposure to high levels of particulate matter (PM2.5 – which consists of particulate matter with a median diameter of less than 2.5 microns, approximately one thirtieth the width of average human hair) is associated with higher rates of early foetal loss, preterm delivery – and lower birthweight.
Children’s lungs are in the process of growing and developing, making them especially vulnerable to polluted air. The cell layer on the inside of the respiratory tract is more permeable among young children. Children’s respiratory airways are also smaller than adult airways, so infections are more likely to cause blockages than in adults. Children breathe twice as fast, taking in more air per unit of body weight, compared to adults.