On January 26, 2026, two major studies brought renewed attention to the invisible threats lurking in everyday life—alcohol and radon gas—by revealing their significant links to cancer risk. While both substances have long been known to pose health hazards, new research is shedding light on just how deeply they may impact cancer rates and what can be done to mitigate their dangers.
In the United States, a groundbreaking study published in Cancer reported that higher lifetime alcohol consumption is linked to a notably increased risk of colorectal cancer, especially rectal cancer. The research, conducted by investigators at the National Cancer Institute (NCI), part of the National Institutes of Health, analyzed data from 88,092 adults enrolled in the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Over a span of 20 years, 1,679 participants developed colorectal cancer, providing a rich dataset for the study’s conclusions.
According to the findings, current drinkers who averaged 14 or more alcoholic drinks per week—classified as heavy drinkers—faced a 25% higher risk of developing colorectal cancer compared to those who drank less than one drink per week. The risk for rectal cancer specifically was even more alarming, with heavy drinkers facing a 95% higher risk than their light-drinking counterparts. The study further revealed that consistent heavy drinking throughout adulthood resulted in a staggering 91% higher risk of colorectal cancer compared to those who maintained light drinking habits.
Yet, there was a silver lining. Former drinkers, those who had quit alcohol, did not show an increased risk of colorectal cancer. In fact, they had lower odds of developing noncancerous colorectal tumors (adenomas) than current light drinkers. This suggests that quitting alcohol may indeed lower an individual’s risk of future colorectal cancer. However, the study’s authors cautioned that data on former drinkers was limited, and more research would be needed to confirm these findings.
As for why alcohol increases cancer risk, the researchers pointed to possible mechanisms such as carcinogens produced during alcohol metabolism and the impact of alcohol on gut microbes. “Our study is one of the first to explore how drinking alcohol over the life course relates to both colorectal adenoma and colorectal cancer risk. While the data on former drinkers were sparse, we were encouraged to see that their risk may return to that of the light drinkers,” said co–senior author Erikka Loftfield, Ph.D., MPH, of the NCI, as reported by Cancer.
Meanwhile, in Canada, another silent threat is being scrutinized: radon gas. CBC News reported on a national study investigating radon exposure as a cause of lung cancer, focusing on the story of Steve Blake, a Calgary resident who developed inoperable Stage 4 lung cancer in 2023 at age 55. Blake had never smoked nor been exposed to secondhand smoke, yet after more than 25 years working in his basement—about six hours a day, five days a week—he was blindsided by the diagnosis. The culprit, he and his wife Kelly discovered, was likely radon gas, detected at high levels in their home.
Radon is a naturally occurring radioactive gas released from the ground as uranium in soil and rock breaks down. It poses little threat when dispersed outdoors, but can become a serious health risk when it accumulates indoors. When inhaled over long periods, radon exposes lung tissue to radiation, damaging cells and increasing the risk of lung cancer. According to CBC News, radon-induced lung cancer kills an estimated 3,200 Canadians annually, making it a significant public health concern.
Despite its dangers, radon remains largely unrecognized among the public. A recent Cross-Canada Radon Survey, released by the Evict Radon team in 2024, found that 18% of Canadian homes now have radon levels at or above the national guideline of 200 becquerels per cubic meter (Bq/m3)—a sharp increase from just 7% in the late 2000s. Scientists attribute this rise to modern building techniques that make homes more airtight, inadvertently trapping radon inside.
To better understand and combat this risk, the Evict Radon study, led by University of Calgary biochemist Aaron Goodarzi, is collecting 10,000 toenail samples from Canadians nationwide by 2028. The science behind this unusual approach is surprisingly straightforward: when people inhale radon, it turns into radioactive lead, which accumulates in slow-growing tissues like toenails. By analyzing these clippings, researchers hope to create a noninvasive test for measuring an individual’s lifetime radon exposure—a tool that could one day influence lung cancer screening criteria.
"We’re looking for a radon signature in that tissue so we could develop a noninvasive or minimally invasive test to determine people’s lifetime exposure to radon, to include them in screening criteria," explained Dr. Alison Wallace, a thoracic surgeon and researcher based in Halifax, to CBC News. The timing, she said, is crucial, as medical teams are now seeing more never-smokers developing lung cancer.
However, current screening programs in Canada remain limited. Only British Columbia and Ontario have permanent lung cancer screening initiatives, and B.C. is the only province running a pilot project that screens non-smokers living in homes with extremely high radon levels (800 Bq/m3 or more). Health Canada is urging other provinces to adopt similar criteria, hoping to catch more cases early and save lives.
For individuals like Steve Blake, awareness came too late. As he and his wife prepared to install a $2,600 radon mitigation system in their Calgary home, they questioned why more isn’t being done to protect Canadians from this invisible hazard. "If we get more information on radon gas and the potential risks, you’re going to get more data and eventually that could be a criteria — a risk factor — so that a non-smoker can go get early screening," Kelly Blake told CBC News.
The combined findings from these studies highlight a broader truth: cancer risks often come from sources that are easily overlooked or underestimated. Whether it’s the glass of wine with dinner or the air inside one’s home, the dangers may be subtle but significant. As scientists race to refine screening tools and public health campaigns, these new insights offer hope that, with vigilance and innovation, the tide of cancer diagnoses can be turned.
For now, the message is clear—awareness and prevention are key. Testing homes for radon, moderating alcohol consumption, and supporting ongoing research could make all the difference in catching cancer early or avoiding it altogether. And while the science continues to evolve, the stories of those affected serve as a powerful reminder: sometimes, the greatest risks are the ones we can’t see.