The most common type of bladder cancer is urothelial carcinoma, and is strongly associated with cigarette smoking. About 50% of all bladder cancers in men and 30% in women may be caused by cigarette smoking. A new small study suggests that children, ages 4 to 10,  who are exposed to secondhand smoke are at a greater risk for bladder irritation.

While bladder irritation isn’t cancer, it involves the urge to urinate, urinating more frequently, incontinence and burning pain. The study revealed that exposure to secondhand smoke is linked to more severe symptoms of bladder irritation: The more exposure the children had, the worse their symptoms became.

Led by Dr. Kelly Johnson, researchers from Robert Wood Johnson University Hospital and Rutgers University analyzed survey information on 45 children ranging in age from 4 to 17. All had symptoms of bladder irritation. The researchers divided the children into four groups based on the severity of their symptoms: very mild, mild, moderate or severe.

Twenty-four of the children studied had moderate to severe symptoms of bladder irritation, while 21 had mild or very mild symptoms.

The children with moderate or severe symptoms were more likely to have consistent exposure to secondhand smoke, the researchers noted. Of these kids, 23 percent had a mother who smoked and 50 percent of them were regularly exposed to secondhand smoke while riding in a car.

On the other hand, the children whose mother didn't smoke and were not exposed to secondhand smoke in the car had only very mild or mild symptoms of bladder irritation.

"Secondhand smoke is a leading cause of preventable death in the United States," Dr. Anthony Atala, a pediatric urologist at Wake Forest Baptist Medical Center and a spokesman for the AUA, said in an association news release. "Beyond conditions such as lung cancer, heart disease and asthma, we now know that smoking has a negative impact on urinary symptoms, particularly in young children. Data presented today should be added to the indisputable evidence that parents shouldn't smoke around their children."

The study did uncover a link between secondhand smoke and bladder problems in children, but it did not prove a defined cause and effect.

While there may not be a direct cause and effect at this stage of the research, it is wise for parents and caregivers to keep children away from people who are smoking. Continuous bladder irritation is not only painful but can lead to infections and bladder damage.