Beat air pollution to protect health: World Environment Day 2019

Beat air pollution – that is the theme for World Environment Day on 5 June. The air that we breathe is fundamental to our existence; yet, we sometimes forget the impact that the quality of the air has on our health and well-being.

Although there are many reasons why the global community should be stepping up action to combat air pollution, perhaps the most compelling is the direct positive impact that such action will have on our health and the health of our children. To mark World Environment Day, Dr Dorota Jarosińska, Programme Manager responsible for air quality at the WHO European Centre for Environment and Health (ECEH) in Bonn, Germany, answered some of the most pressing questions about air pollution, its impacts on health and what we are doing about it.

First of all, what is air pollution?

Dr Dorota Jarosińska: Air pollution is the contamination of the air we breathe, indoors or outdoors, by any chemical, physical or biological agent that modifies its natural characteristics. The pollutants with the strongest evidence for public health concern include particulate matter (PM), ozone (O3), nitrogen dioxide (NO2) and sulphur dioxide (SO2). The health risks associated with particulate matter smaller than 10 and 2.5 microns in diameter (PM10 and PM2.5) are of particular public health relevance. Particulate matter is capable of penetrating deep into lung passageways and entering the bloodstream, primarily resulting in cardiovascular and respiratory impacts. In 2013, outdoor air pollution and particulate matter were classified as carcinogenic by WHO’s International Agency for Research on Cancer (IARC).

How does air pollution actually impact health?

Air pollution affects everyone. It is the second leading cause of death from noncommunicable diseases (NCDs) after tobacco smoking. In 2016 in the WHO European Region, more than 550 000 deaths were attributable to the joint effects of household and ambient (or outdoor) air pollution. In children and adults, both short- and long-term exposure to ambient air pollution can affect their health. In children, this could include reduced lung growth and function, respiratory infections and aggravated asthma. In adults, ischaemic heart disease and stroke are the most common causes of premature death attributable to outdoor air pollution. Evidence is also emerging of other effects of air pollution, such as diabetes, neurodevelopment issues in children and neurodegenerative conditions in adults.

WHO has established guidelines for air quality to protect health – can you tell us a little bit more about them?

Since the mid-1980s, WHO through the Regional Office for Europe has coordinated the development of a series of air quality guidelines. They provide guideline values for several air pollutants, which if achieved, would result in a significant reduction in risk for health effects. Although the guidelines are not legally binding, they have been widely used as a reference to help policy-makers across the world in setting standards and goals for air quality management. They also provide recommendations on developing public health policy and tools.

The last edition of the guidelines is from 2005, are they still valid and will they be updated?

The WHO Air Quality Guidelines (AQG) were updated in 2005 and include recommendations for the four most common air pollutants: particulate matter, ozone, nitrogen dioxide and sulphur dioxide. They were based on a review of the accumulated scientific evidence at the time, and as such, they still offer solid health arguments for improving air quality. Since then, the evidence base for adverse health effects related to short- and long-term exposure to these pollutants has become much larger and broader. As a result, in 2016 WHO started work towards producing an update of the AQG, and this project is ongoing.

Who is exposed to air pollution?

Almost everybody is exposed to air pollution. Although a lot is being done to improve air quality, evidence of adverse health effects from air pollution persists in many parts of the world including in the European Region. For example, despite reductions in emissions of PM10, the majority of the urban population in monitored European countries between 2000 and 2015 was exposed to concentrations above the WHO AQG annual guideline value, as reported to the European Environment Agency.

What can be done to improve air quality?

To improve air quality, we need to tackle the many sources of air pollution. The most common sectors contributing to air pollution are agriculture, energy, transport, industry, commerce and waste, plus household solid fuel combustion; another important source of indoor air pollution is tobacco smoke. Therefore, we need a very broad approach to addressing air pollution. A lot of changes are happening in our Member States to contribute to improvements in air quality, but we need to be doing much more.

Some good examples of steps that many countries and municipalities have already taken are:

  • introducing clean technologies in industry to reduce smokestack emissions, and improving waste management;
  • ensuring access to affordable clean energy for cooking, heating and lighting in households;
  • prioritizing public transport in urban areas, walking and cycling networks and interurban rail travel;
  • improving the energy efficiency of buildings; making cities greener, more compact and thus more energy efficient;
  • increasing the use of renewable power sources, such as solar, wind and hydropower;
  • introducing strategies for waste reduction, separation, recycling and reuse or reprocessing.

In 2018, the third United Nations High-level Meeting on NCDs recognized household and outdoor air pollution as a risk factor for NCDs, alongside unhealthy diets, tobacco smoking, harmful use of alcohol and physical inactivity.

What is WHO doing to support its Member States?

WHO/Europe supports Member States within the European Environment and Health Process through technical support, capacity-building and advocacy. As already mentioned, WHO is currently working on updating the global AQG to provide revised values for several air pollutants. We have also developed tools, such as AirQ+ to quantify the health effects of exposure to air pollution, as well as tools that support health arguments for urban and climate change mitigation policies.

WHO ECEH also chairs the Joint Task Force on the Health Aspects of Air Pollution of the United Nations Economic Commission for Europe (UNECE) Convention on Long-range Transboundary Air Pollution (LRTAP). Within the Task Force, environmental and public health experts work to monitor and address human health effects of air pollution and help to define future priorities.