Climate change will bring an acute toll worldwide, with rising temperatures, wildfires and poor air quality, accompanied by higher rates of cancer, especially lung, skin and gastrointestinal cancers, according to a new report from UC San Francisco.  

Female Doctor Examining Pigmented Skin On Man’s Back With Dermatoscope

The review published in The Lancet Oncology outlines the future effects of global warming on major cancers by examining nearly five dozen published scientific papers. It detailed the impact of environmental toxins such as ultraviolet radiation, air pollution, infectious agents and disruptions in the food and water supply.  

The most profound challenge to the global cancer picture could come from the disruption of the complex health care systems required for cancer diagnosis, treatment, and care, the authors wrote. This ultimately has the potential to regress or stagnate developments that have helped reduce morbidity and mortality rates. 

Lead author Robert A. Hiatt, MD, PhD, UCSF professor of Epidemiology and Biostatistics, and associate director for population science at the UCSF Helen Diller Family Comprehensive Cancer Center, said: 

“What I have observed is progress. Things have got better in places like Australia, the UK, and North America in terms of cancer mortality, going downward since the mid-90s. As time goes on more and more is learned about how to prevent and care for cancer and so if there weren’t this ominous specter of climate change infront of us, we could expect to have continued improvement in cancer control.”

In the global challenge to mitigate climate, the international community is not acting at a fast enough rate to slow emissions of greenhouse gases and prevent the subsequent fallout. According to Hiatt, the resulting impact on cancer treatment could see healthcare trends change. He said: 

“Cancer treatment progress could be reversed. That is a concern. Right now if climate change wasn’t there you could expect a continued improvement, especially in high-income countries. One of the threats that climate change presents is that it will slow or reverse this improvement.” 

The disruptions that could lead to these potential halts in progress and challenges to infrastructure are raised by the threat of extreme weather events such as storms and flooding which are made more common by climate change. Such events cause power shortages in a system reliant on data, and where several specialised oncologists will require access to patient information. 

With the impact of climate change the biggest cancer threats are likely to be from air pollution, exposure to ultraviolet radiation and industrial toxins, and disruptions in food and water supply. Whilst lung cancer –  already the primary cause of cancer deaths worldwide – will escalate due to greater exposure to particulate matter in air pollution, the indirect impact of climate change has the potential to raise issues surrounding melanoma. Hiatt said: 

“With melanoma, it takes people going out into the sun unprotected to expose themselves to UV radiation. There has been an ozone layer which has been reduced so the only thing that is going to make it worse is if temperatures rise and people would be comfortable with exposing themselves. That is an indirect effect of climate change, but still quite likely.”

To ensure medical progress isn’t abbreviated and the disruption to healthcare systems is reduced, the research advocated for both mitigation and adaptation to the impact of climate change which will affect low-and-middle-income disproportionately. This comes with collective mitigation where fossil fuel reliance decreases alongside adaptation methods of adaptation to limit the effects of sea-level rise and wildfires.