Tackling the ‘unknowns’ of air pollution

The recently updated Global Air Quality Guidelines (AQGs) issued by the World Health Organisation (WHO) means that air pollution is again at the forefront of our conversations. These new AQGs provide clear evidence of the damage that air pollution has on human health and in lower concentrations than previously understood.

They also emphasise that any decrease in exposure in areas with both high and low concentration levels will lead to better health of the population. This means that governments around the world must revise their clean air policies and strategies if they are to implement the lower levels of key air pollutants recommended by WHO. Collectively adhering to the new guidelines could save millions of lives as well as mitigating climate change. National and local policymakers are now faced with the unenviable yet critical challenge of responding.



Improving our understanding of air pollution

While we understand a lot about how air pollution affects our health, there are still many unknowns.  In the LongITools project, we are trying to answer some of the unknowns by studying the effect of air pollution, mainly from traffic, and its interaction with other exposures, on cardiometabolic and cardiovascular health. Importantly, we know that people or populations exposed to air pollution are often living in complex environments, with social and psychosocial disparities, that also include periods of susceptibility during the life-course.

For example, our researchers  are studying the effect of exposure to air pollutants such as PM and nitrogen dioxide (NO2) on the risk of developing and living with obesity. Our studies will answer whether the effect of exposure on obesity is independent from other risk factors or is modified through interaction with other related environmental factors, such as noise pollution, food borne and built environment exposures. Critically we must also analyse when and where the risk develops to identify the most vulnerable populations and the opportunity for prevention.

Our project is part of the European Human Exposome Network (EHEN), the world’s largest network of projects studying the impact of environmental exposures across a lifetime – the exposome – on human health. It is vital we understand how numerous environmental exposures, including air pollution, interact with one another to impact our health and wellbeing. LongITools and EHEN aim to do just that.

Acting on the findings

It is important that the LongITools research findings can be turned into action. This is why we are already talking to policymakers about our research – to raise awareness of the unknowns our research questions hope to address. One of the ways we are doing this is by holding regular policy forums on different topics relating to our research.

During our recent LongITools policy forum on air pollution, Dr Kevin Cromar, program director at the Marron Institute of Urban Management, New York University, shared his experience of working at the interface of scientific research and public policy. He explained the importance of considering the health risks that occur due to both long- and short-term exposures when designing solutions to reduce harmful emissions. Although air pollution affects all of us, ambient concentrations can vary dramatically within the same airshed, with hot-spot locations of elevated pollutant concentrations. It is therefore crucial to consider potential environmental justice issues in designing specific remediation policies to address areas with elevated exposure levels.  In the short-term educating people to take protective measures to reduce their own exposure can also be an effective approach to reducing health risks, but risk communication should be secondary to efforts to decrease emissions.

One of the key issues to consider in designing policies to improve air quality is to identify the largest modifiable sources of air pollution, taking into account jurisdictional, technological, and economic considerations. This may or may not include the largest emissions sources overall but will be the sources in which the largest reductions can be realised.  This way of thinking can be greatly enhanced using economic analysis that considers both the costs and the benefits the of proposed policy actions.  They should therefore not only take into account any direct economic benefits, but also consider the health benefits arising from improved air quality, and in some cases can even also include climate related benefits.


More information

WHO Air Quality Guidelines

EHEN (EXPANSE and LongITools) researcher Gerard Hoek was involved in the study leading to the new WHO Air Quality Guidelines

Have your say: Air Quality Revision of EU Rules – Public Consultation