Toenails: A New Window into Radon Exposure and Lung Cancer risk
Radon, a naturally occurring radioactive gas, is the second leading cause of lung cancer, notably impacting non-smokers. This invisible and odorless gas originates in soil and rocks – especially those containing uranium – and can seep into buildings through foundations and groundwater. It can also be released from building materials and tends to concentrate in poorly ventilated spaces like basements and cellars, posing a risk in mines, tunnels, factories, and some offices.
While radon itself decays into a chain of radioactive elements, ultimately stabilizing as lead, a recent study suggests a surprising place this lead accumulates within the human body: toenails. Researchers have found that slowly eliminated tissues like skin, hair, and especially nails, store this lead, effectively acting as a “biological archive” of past radon exposure.
Canadian researchers are pioneering a new method to assess individual radon exposure by combining conventional radon dosimeter measurements of a home with analysis of toenail samples from its occupants. This approach promises to effectively and individually quantify long-term radon exposure,offering a significant advancement in preventative healthcare.
“We combined the measurement of radioactivity with precision biological analysis. Toenails turn out to be an excellent marker of our cumulative exposure,” explains Aaron Goodarzi, the study’s lead author.
If validated on a larger scale, this method could revolutionize lung cancer prevention, particularly for those who don’t smoke and are therefore excluded from current screening programs. It offers a simple, minimally invasive, and accessible way to detect perhaps dangerous exposures before symptoms appear.
Currently, protecting yourself from radon exposure involves simple steps like daily ventilation – opening windows for at least ten minutes – to prevent gas buildup. Certain regions of France are particularly susceptible due to thier geological composition, including the Alps, Brittany, Corsica, the Massif Central, and the Vosges. The Nuclear Safety and Radiation Protection Authority (ASNR) provides an interactive map to identify at-risk municipalities.
Individuals concerned about radon levels can also install a dosimeter in their home for a few weeks to measure indoor air concentration. Levels exceeding 300 Bq/m³ may warrant renovations to improve sealing between walls and floors or upgrade ventilation systems. Concentrations above 1,000 Bq/m³ require professional assessment and remediation.
