Air pollution can effect our health in many ways with both long and short term effects. Urban outdoor air pollution increases the risk of acute (e.g. pneumonia) and chronic (e.g. lung cancer) respiratory disease as well as cardiovascular disease. Different groups of individuals are affected by air pollution in different ways. More severe health impacts are seen among those people who are already ill. In addition, more vulnerable populations like children, the elderly and those households with lower incomes and limited access to health care are more susceptible to the adverse effects from exposure to air pollution.
Worldwide it is estimated that 1.3 million people — more than half of them in developing countries — die every year from urban outdoor air pollution. Urban outdoor air pollution is a major environmental health problem affecting people in both developed and developing countries. Populations living in cities with high levels of outdoor air pollution will have more heart disease, respiratory problems and lung cancers than those populations living in urban areas with cleaner air.
Health effects are seen from both short and long term exposure to urban outdoor air pollution. For example, asthmatics are at an increased risk of an asthma attack on a single day with higher ground-level ozone concentrations. Whereas for example, individuals exposed chronically (e.g. years) to high levels of particulate matter are at increased risk for cardiovascular disease.
A cities health burden form urban outdoor air pollution depends on levels of pollutants in that city as well as on the number of people who breathe the pollution. A disproportionate health burden from urban outdoor air pollution is observed in middle-income countries. The large and rapid increase in the number of motor vehicles, especially those with older engines and using poorer quality fuels, as well as the increase in power generation from coal and other dirty fuels, has put the populations of these emerging economies at some of the greatest health risks from polluted air. In many of these rapidly growing economies, regulations and policies have yet to be put in place or be implemented more rigorously to help curb emissions and maintain a healthy and clean air.
As these regions continue to grow and expand, so does the need for action to clean the air and protect population health. Health concerns are not limited to the most polluted cities: substantial health effects are seen even in the relative cleaner cities of Australia, Europe, New Zealand or North America, where PM levels are typically 3-10 times lower than in the most polluted cities. The lower the level of air pollution in a city, the more protected is the health of its population.
Cities can identify their main sources of outdoor air pollution, and implement policies known to improve air quality, such as: promotion of public transport, walking, and cycling (rather than transport relying on private motor vehicles); promotion of power plants that use clean and renewable fuels (e.g. not coal), and improvements in the energy efficiency of buildings and manufacturing. Essential accompanying steps include increasing awareness about the high disease burden from urban outdoor air pollution and its main sources, as well as highlighting the importance of taking action now to implement country-specific interventions.
In addition, the use of effective monitoring to evaluate and communicate the impact of interventions is also an important tool in raising awareness. It can help drive policy action that brings benefits for health, climate and the environment.