Long-term exposure to air pollution (PM2.5) raises risk of developing cancer by 11 % and of dying from cancer by 12 %

The Union for International Cancer Control (UICC), with support from the Clean Air Fund, has released a global report, Clean air in cancer control: An overview of the evidence, presenting data on the scale of cancer risk and mortality from polluted air. The findings confirm that air pollution is not only a driver of lung cancer but also significantly increases the risk of developing multiple other cancers and of premature death.

Air pollution has long been known as a major health hazard and a major cancer risk factor, but until now the full picture of its impact on cancer incidence and survival beyond lung cancer had not been fully studied. This report helps close that gap.

“We have made huge strides in reducing deaths from cancer, but polluted air is silently undermining that progress. It is a risk people cannot opt out of, and one that disproportionately affects women, children and people living in poverty.” – Cary Adams, CEO of UICC

Key findings: What the report reveals

• Air pollution is a multi-cancer risk factor:
  • Comparing people living with higher long-term PM2.5 levels to those in less polluted environments, the papers synthesized in the report suggest an 11 % higher overall risk of developing cancer.
  • Higher PM2.5 levels are associated with a 32 % higher incidence of liver cancer and with a 18 % increase in the odds of developing colorectal cancer.
• As long-term PM2.5 pollution levels rise, cancer mortality rises too. The report links higher PM2.5 levels to a 12 % higher risk of death from all cancers. There is specifically a higher mortality for breast cancer (20 %), liver cancer (14 %), and lung cancer (13 %).
• The report also summarizes emerging evidence linking higher PM2.5 exposure to other cancer types, including kidney, bladder and brain cancer. Note that the strength of the evidence varies by cancer type, so results are less certain for cancers with fewer studies.
• Long-term exposure to larger air pollutants (PM10) is also associated with a 10 % higher overall risk of an individual developing cancer, and a 13 % increased risk of dying from lung cancer and 11 % increased risk of dying from breast cancer.
• Emerging evidence also shows a 63 % higher risk of brain cancer for people with higher long‑term absorption of fine particulate air pollution (PM2.5). Absorption refers to how much pollution is taken up by the body over time: Because PM2.5 particles are small enough to pass from the lungs into the bloodstream and reach the brain, greater long‑term uptake, not just higher levels in the air, is linked to increased cancer risk.
• Preventable deaths: Ambient air pollution is estimated to contribute to around 434,000 lung-cancer related deaths each year.

The report also highlights that these risks are not shared equally. Women and children exposed to smoke from solid fuels for cooking and heating, with women exposed to household air pollution face a 69 % higher risk of lung cancer, alongside increased risks of cervical cancer. In addition, outdoor workers, and communities near industrial facilities – often economically deprived communities – face the highest levels of exposure.

Low- and middle-income countries overall bear the greatest burden, with limited resources to reduce pollution or access to timely cancer care, compounding health and economic inequities. These are also the countries whose health systems are least equipped to deal with the projected rise in cancer cases over the next decades, from 20 million in 2022 to 35 million in 2050.

The report notes that, while research gaps remain, the evidence is already strong enough to justify decisive action. Because people can’t realistically ‘opt out’ of the air they breathe, reducing air pollution at source depends on government action through energy, transport, and industrial policy.

Effective policies to reduce air pollution exist, including stronger emissions standards, cleaner energy, improved urban design, and expanded air quality monitoring. Despite more than 140 countries having air quality standards, only around one third enforce them, leaving populations exposed to avoidable cancer risks.

Proven interventions can deliver rapid health gains. From high-income cities such as Barcelona with its ‘Superblocks’ program, to middle-income cities such as Bogotá, with its ‘Open Streets’ program, measures that cut traffic and prioritize walking, cycling, and clean public transport have been linked to quantified health benefits including fewer preventable deaths.”

Key measures include:

• Develop and legally enforce air-quality standards aligned with WHO guidelines and the target adopted unanimously at the World Health Assembly in May 2025 to halve mortality from air pollution by 2040 compared with 2015, backed by robust monitoring systems.
• Expand air quality monitoring particularly in low‑ and middle‑income countries and highly exposed communities, to inform action and accountability.
• Transition away from fossil fuel and biomass burning to clean energy and clean cooking, particularly in regions where household air pollution remains high.
• Reform transport and urban policies to reduce emissions and protect public health, such as enforcing vehicle emissions standards, supporting use of public transport and active mobility and investing in expanding green spaces.
• Integrate air-quality targets into national cancer control plans, ensuring cancer prevention strategies address environmental risks.

Cleaner air is urgently needed to head off the expected rise in cancer in the coming decades, especially in low- and middle-income countries. Clean air is essential to both cancer prevention and improving survival. Without it, decades of investment in cancer research and treatments will be needlessly undermined. The benefits of action will be counted in lives saved, successful treatments, and cost savings for health systems. Governments must act decisively, to enforce emissions standards, shift to clean energy, and embed air-quality goals into health strategies and national cancer control plans.”

Nina Renshaw, Head of Health, Clean Air Fund

This report was commissioned by UICC, research was conducted by The George Institute for Global Health, with support from the Clean Air Fund. It synthesizes findings from 42 meta-analyzes and systematic reviews, published between 2019 and 2024.