The findings of three separate studies suggest that side effects of vaping e-cigarettes, which have become an increasingly popular alternative to traditional smoking, may increase the risk of bladder cancer.
More than 90% of inhaled nicotine is excreted in the urine, according to researchers, concentrating the bladder’s exposure to nicotine and other harmful chemicals from vaping and traditional cigarettes.
The studies were presented earlier this week at the 12th Annual Scientific Meeting of the American Urological Association (AUA), identifying links between e-cigarette use and bladder cancer, according to an AUA press release. The findings are considered preliminary until published in a peer-reviewed journal.
In the first report, researchers compared the urine of e-cigarette users to non-users. Non-smokers must have abstained from traditional cigarettes for at least six months. The urine was examined for five known bladder carcinogens, which are present in traditional cigarettes and common solvents known to be used in vaping liquids.
Nearly 92% of e-cigarette users tested positive for two of the five carcinogens, chemicals which increase the patient’s risk of bladder cancer.
A similar study published last year indicated vaping increased a person’s risk of suffering oral cancer and other oral diseases. The chemicals caused about 85% of cells in the mouth to die.
The second study focused on whether e-cigarette vapors induced DNA damage in the bladder cells.
Researchers concluded e-cigarette vapors induced tumorigenic DNA damage to bladder mucosa. It also indicated nicotine, nitrosamine, and formaldehyde induced the same types of DNA damage in human urothelial cells, the tissue that forms the bladder. The chemicals also prevented DNA repair and ramped up mutational susceptibility.
The data indicated the nicotine from vaping can be nitrosatized in urothelial cells and metabolized into carcinogenic nitrosamines and formaldehyde, causing further damage to the bladder tissue.
The third study focused on the survival rates among 14,000 smoking adults with bladder cancer in Florida from 1981 to 2009. Data from patients who smoked less than one pack of cigarettes a day was compared to those who smoked one to two packs per day and to those who smoked more than two packs per day.
Researchers concluded smoking more packs per day was linked to an increased risk of death among patients who already had bladder cancer. Smoking one to two packs per day increased a person’s likelihood of death significantly, compared to patients that smoked less than one pack per day.
The data indicated reducing the number of traditional cigarettes smoked, even by a small amount, would allow a patient to survive longer with bladder cancer.