Air pollution: an existential crisis reversing the progress made in cancer control

The figures are staggering. Only 1% or the world’s population – about 80 million people out of 8 billion – breathe air that does not threaten their health.

Air pollution is now known to cause 6.7 million deaths per year, nearly the same toll exacted by COVID-19 in terms of excess mortality in 2020 and 2021. Low- and middle-income countries pay a much heavier toll, accounting for 91% of premature deaths related to air pollution.

The global cost of health damages associated with exposure to air pollution is estimated at USD 8.1 trillion, equivalent to 6.1 percent of global GDP.

Air pollution, or fine particulate matter present in the air, is a mix of solid particles and liquid droplets. Some of the most common forms are soil, dust, soot or smoke, and they come from coal- and natural gas-fired plants, cars, agriculture, wildfires, wood-burning stoves, unpaved roads and construction sites, amongst others.

Breathing this in poses significant health harms, including increased risks of cancer and stroke as well as respiratory and cardiovascular diseases. In fact, the risks are very similar to those associated with smoking tobacco. Exposure to particle pollution can drive rapid changes in airway cells that can trigger lung cancer – changes that are seen in about half of people with lung cancer who have never smoked.

“The same particles in the air that derive from the combustion of fossil fuels, exacerbating climate change, are directly impacting human health via an important and previously overlooked cancer-causing mechanism in lung cells,” said Prof. Charles Swanton of the Francis Crick Institute last year when presenting research at the ESMO 2022 Presidential Symposium.

The Lancet Commission on pollution and health established in 2015 that air pollution causes as many as 15% of all lung cancer deaths, with all forms of pollution causing 43% of lung cancer deaths. 

A 2022 update confirmed these figures, also marking that there was a decline in deaths from indoor pollution, notably in Africa, due to improved sanitation and cleaner fuels. This decline, however, has been outpaced by the significant global increase over the past 20 years in “deaths from the modern forms of pollution (ie, ambient particulate matter air pollution, ambient ozone pollution, lead exposure, occupational carcinogens, occupational particulate matter, gases, fumes, and environmental chemical pollution)”. 

Implementing measures such as fostering the transition to renewable energy, promoting public transportation, bicycling and walking, increasing green spaces, and strengthening pollution control policies can significantly reduce air pollution. Not only do these actions directly lower cancer and disease risk by reducing exposure to harmful pollutants, but they also indirectly promote better health by creating environments conducive to physical activity.

“So much progress has been achieved in preventing and treating cancer and in the quality of life of people living with cancer. Air pollution is threatening this progress by contributing to the rise of the number of cancer diagnoses each year – cancers that are preventable. Together with the global health community, we must take concrete action to transition to cleaner energy sources, safeguard human and planetary health, prevent cancer diagnoses, and ensure a sustainable future for generations to come.”
– Dr Sonali Johnson, Head of Knowledge and Advocacy, UICC

Awareness about the dangers of air pollution is growing. 6,000 cities in 117 countries now measure air quality but there is no evidence that this monitoring has yet led to an improvement in air quality. In fact, not a single one of the world’s 100 biggest cities has managed to meet WHO air pollution guidelines.

In 2015, governments adopted a resolution at the World Health Assembly, which recognises that air pollution causes global health inequities, disproportionately affecting children, women and older adults, as well as low-income populations.

WHO developed an action plan to respond to the impacts of air pollution on different populations. It is developing a series of cost-effective measures to accompany the NCD ‘Best Buys’ and has issued global Air Quality Guidelines.

Aligned with the UN’s call to end the financing of fossil fuels, UICC is urging governments to enact effective regulation to curb emissions and drastically reduce the use of fossil fuels and other air pollutants. It supports global development initiatives to assist lower-income countries in transitioning to cleaner household heating and cooking materials, and cleaner energy sources in general.  

Commenting on a Lancet Planetary Health study that he co-authored, Professor Philip Landrigan said: “Pollution is still the largest existential threat to human and planetary health and jeopardizes the sustainability of modern societies.”

UICC is making air pollution and cancer a key focus of its work, working with the Clean Air Fund, establishing an expert group to synthesise the latest global evidence, spotlighting best practices and identifying research gaps on the impact of air pollution on cancer. UICC also supports a World Health Assembly resolution on climate change and health.

In the coming months, UICC will be making resources available for its members to advocate nationally and locally for cleaner air.

Visit UICC’s dedicated page on air pollution and cancer