Climate change will give rise to more cancers

November 04, 2020

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.

In an analysis of nearly five dozen published scientific papers, the researchers provided a synopsis of future effects from global warming on major cancers, from environmental toxins to ultraviolet radiation, air pollution, infectious agents and disruptions in the food and water supply.

Ultimately, 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. The review appears in The Lancet Oncology.

"In the worldwide battle to mitigate climate change, the international community is not on track to slow emissions of greenhouses gases," said 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. "2015-2019 were the five warmest years on record, and 2020 has seen tremendous climate impacts, from wildfires to hurricanes."

The impacts of climate change on health are large and are expected to continue growing without rapid action. High temperatures, poor air quality and wildfires cause higher rates of respiratory and cardiovascular diseases. Warmer temperatures and changing rainfall patterns raise the risk and spread of vector-borne disease, such as malaria and dengue. "Extreme weather events cause death, injury, displacement, and disrupt health-care delivery," the authors wrote.

Cancer is widely predicted to be the leading cause of death in the 21st century. Worldwide, there were 24.5 million new cases of cancer and 9.6 million deaths in 2017, a striking increase from 2008 with 12.7 million cases and 7.6 million deaths.

The authors said the biggest cancer threats are likely to be from air pollution, exposure to ultraviolent radiation and industrial toxins, and disruptions in food and water supply. Lung cancer, already the primary cause of cancer deaths worldwide, is expected to increase as a result of escalating exposure to particulate matter in air pollution, estimated to be responsible for as much as 15 percent of new cases.

While the overall effects of climate change on nutrition-related cancers are difficult to determine, the authors said, one comprehensive modeling study predicted more than half a million climate-related deaths worldwide, including cancer deaths, as a result of changes in food supply by 2050, such as reduced consumption of fruits and vegetables.

Climate change is already exacerbating social and economic inequities, leading to higher rates of migration and poverty. The authors note that poor people and communities of color are disproportionately affected by cancer and have a higher cancer mortality. World Bank estimates that climate change will push 100 million people globally back into poverty by 2030.

Major disruptions are also expected to take place in the infrastructure of health care systems for cancer control, which could affect all cancers. The COVID-19 pandemic has provided a clear example of this disruption, shifting medical resources away from cancer and causing thousands of patients to delay cancer screenings out of fear of contracting the virus.

"Extreme weather events such as storms and flooding can destroy or damage health-care infrastructure, reducing health care quality and availability," said the authors. These events also interrupt service delivery by causing power shortages, disrupting supply chains, transportation, and communication, and resulting in staff shortages. Ironically, COVID-19 also revealed a ray of hope in reversing the damage.

"The early pandemic response resulted in a striking reduction in air pollution," Hiatt said, "showing the potential of extreme measures to result in rapid environmental change."

It could take decades to fully understand the impact of climate change on cancer, given a sometimes lengthy delay from exposure to clinical diagnosis. But the authors said that shouldn't prevent acting now, as the harmful impacts from air pollution and other climate risks will continue to grow during that time.

"There is a lot we can be doing to mitigate climate change and to mitigate the impact on cancer," said co-author Naomi Beyeler, MPH, co-director of the Evidence to Policy Initiative and Lead for Climate and Health at the UCSF Institute for Global Health Sciences. "We should be doing both, and we should be doing both with urgency."

By reducing pollution, deaths from lung cancer could decline, the authors said, and there are numerous clinical, behavioral, and policy solutions to slow climate change, and prevent cancer cases and deaths.

"The COVID-19 pandemic has shown us the importance of science and public health," said Beyeler, "and we have seen over the past months that as a global health community, we are able to mobilize the investments, research, and collective action needed to solve health problems on a global scale. Now is the time to apply this ambition to tackling the climate crisis."
-end-
About UCSF:

The University of California, San Francisco (UCSF) is exclusively focused on the health sciences and is dedicated to promoting health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care. UCSF Health, which serves as UCSF's primary academic medical center, includes top-ranked specialty hospitals and other clinical programs, and has affiliations throughout the Bay Area. Learn more at ucsf.edu, or see our Fact Sheet.

Follow UCSF
ucsf.edu | Facebook.com/ucsf | YouTube.com/ucsf

University of California - San Francisco

Related Climate Change Articles from Brightsurf:

Are climate scientists being too cautious when linking extreme weather to climate change?
Climate science has focused on avoiding false alarms when linking extreme events to climate change.

Mysterious climate change
New research findings underline the crucial role that sea ice throughout the Southern Ocean played for atmospheric CO2 in times of rapid climate change in the past.

Mapping the path of climate change
Predicting a major transition, such as climate change, is extremely difficult, but the probabilistic framework developed by the authors is the first step in identifying the path between a shift in two environmental states.

Small change for climate change: Time to increase research funding to save the world
A new study shows that there is a huge disproportion in the level of funding for social science research into the greatest challenge in combating global warming -- how to get individuals and societies to overcome ingrained human habits to make the changes necessary to mitigate climate change.

Sub-national 'climate clubs' could offer key to combating climate change
'Climate clubs' offering membership for sub-national states, in addition to just countries, could speed up progress towards a globally harmonized climate change policy, which in turn offers a way to achieve stronger climate policies in all countries.

Review of Chinese atmospheric science research over the past 70 years: Climate and climate change
Over the past 70 years since the foundation of the People's Republic of China, Chinese scientists have made great contributions to various fields in the research of atmospheric sciences, which attracted worldwide attention.

A CERN for climate change
In a Perspective article appearing in this week's Proceedings of the National Academy of Sciences, Tim Palmer (Oxford University), and Bjorn Stevens (Max Planck Society), critically reflect on the present state of Earth system modelling.

Fairy-wrens change breeding habits to cope with climate change
Warmer temperatures linked to climate change are having a big impact on the breeding habits of one of Australia's most recognisable bird species, according to researchers at The Australian National University (ANU).

Believing in climate change doesn't mean you are preparing for climate change, study finds
Notre Dame researchers found that although coastal homeowners may perceive a worsening of climate change-related hazards, these attitudes are largely unrelated to a homeowner's expectations of actual home damage.

Older forests resist change -- climate change, that is
Older forests in eastern North America are less vulnerable to climate change than younger forests, particularly for carbon storage, timber production, and biodiversity, new research finds.

Read More: Climate Change News and Climate Change Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.