Improving the worst environments in the US could prevent 39 in every 100,000 cancer deaths.
That’s according to the first study to address the impact of cumulative exposure to environmental hazards on cancer incidence in the US, which found strong links between poor environmental quality and increased rates of cancer.
The environment we live in can influence biological processes such as hormone function and gene expression, or cause DNA damage – all of which can alter the risk of developing certain cancers. For instance, lung cancer incidence can increase due to chronic exposure to certain pesticides, diesel exhaust and the radioactive gas radon. Social factors also take their toll – poverty is linked to liver cancer, for example, due to increased alcohol consumption.
Jyotsna Jagai at the University of Illinois and her colleagues investigated these links by comparing data from the Environmental Quality Index – a measure of cumulative environmental exposures between the years of 2000 and 2005 – with cancer incidence across the US from 2006 to 2010.
The results showed increases in cancer incidence with decreasing environmental quality. The link was clearest with prostate and breast cancer.
Data under threat
“There is a tension in the field as to whether to focus on individual or cumulative environmental exposures,” says Scarlett Gomez of the Cancer Prevention Institute of California in an accompanying editorial. She says that although identifying individual exposures can allow them to be addressed in a targeted way, pinpointing them can be difficult because many potential cancer factors are linked together. For example, people of low socioeconomic status tend to live in areas that score poorly for multiple environmental factors.
Even so, the data compiled by Jagai’s team can at least help identify which communities are most vulnerable to high cancer rates. However, this may be hampered by new legislative proposals, introduced in January, that seek to rein in federal collection of local area data.
Jagai and her team also warn that a bill introduced in February to terminate the Environmental Protection Agency, which provided the environmental data used in the study, will severely harm researchers’ abilities to further investigate the factors that contribute to disease.
Journal reference: Cancer, DOI: 10.1002/cncr.30709
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