The toenails, an indicator of lung cancer
March 9, 2011.- Nicotine levels in the nails can fairly accurately predict the risk that has a smoker and a nonsmoker exposed to secondhand smoke, to develop the disease in the future.
The study, conducted at the University of California, San Diego, found that “the toenails, which grow very slowly, provide a barometer of chronic exposure to tobacco snuff.”
The American Journal of Epidemiology published this investigation. Experts found that men with higher levels of nicotine in their toenails showed 3.5 times more likely to develop lung cancer than those with lower levels.
Nicotine levels in the nails are relatively stable, compared with the urine or saliva. This is because the nails grow very slowly, almost an inch a year.
Experts believe that “this finding could lead to new tests to detect lung tumors.”
Lead researcher, Professor Wael Al-Delaimy, said “Whether you are a smoker or a nonsmoker exposed to passive smoke snuff, we can now measure to better exposure to smoke and to predict their risk.”
“The toenails can be stored at room temperature for many years. And it may represent exposure to nicotine during the past year.”
During the study experts analyzed “toenails of 850 men in 1987 when the experiment began. The nails were analyzed to measure the levels of nicotine and scientists followed the participants for 12 years to see who developed lung cancer.”
The conclusion showed that “those who developed the disease had, at baseline, an average nicotine level of about 0.95 nanograms per milligram. But those who did not develop the tumor had only 0.25 ng per mg. In addition, over 10% of men with higher levels of nicotine had never smoked. This analysis reveals that some samples also have hidden risks of passive smoking.”