Studies Find Second-hand Smoke Risks

As health advocates go before the Augusta Commission today to ask for a tougher smoking cigarettes ordinance, studies are emerging on the potential dangers of secondhand smoke. In two unrelated studies in separate medical journals, researchers found that male mice exposed to secondhand smoke cigarettes had a higher level of mutations in their sperm, while others studying adolescents exposed to secondhand smoke cigarettes found they had a higher level of hearing loss.

In the first study, published Tuesday in the Proceedings of the National Academy of Sciences , researchers at Lawrence Berkeley National Laboratory and Health Canada exposed male mice to passive cigarette smoke. In levels as low as 20 minutes a day for two weeks, they later found more than twice as many mutations in their sperm as unexposed mice and similar to mice exposed to more direct cigarette smoke. The authors note that previous studies found male smokers at high risk for sperm mutations and other reproductive-related problems.

Smoking's impact on fertility is one reason the in vitro fertilization program at Medical College of Georgia Hospital and Clinics tells people to quit first, said Dr. Lawrence C. Layman, the chief of the section of reproductive endocrinology, infertility and genetics in the Department of Obstetrics and Gynecology. "We don't do in vitro fertilization on people unless they stop," he said.

In the second study, published in Archives of Otolaryngology-Head & Neck Surgery , researchers at NYU School of Medicine, studied 1,533 adolescents, more than half of whom were exposed to secondhand smoke. Those exposed had nearly twice the rate of hearing loss as others and 82 percent were unaware they had any hearing loss.

The authors noted that smoking cigarettes is associated with accelerated hearing loss in adults due to injury to the inner ear and their findings suggest it "may begin at a very early age and may also include those who do not actively smoke cigarettes but who are passively exposed."

More than half of adolescents in the U.S. are exposed to secondhand smoke, similar to the study group, so the finding of hearing loss in that population " has significant implications for public health in the United States," the study concludes.

The hearing loss study was a surprise to Lora Scarlet Hawk, Breathe Easy Coalition Manager for the American Cancer Society, who is helping local groups push for the Augusta ordinance. But advocates already had ample evidence that secondhand smoke cigarettes is dangerous, she said.

"The aspects that we're presenting to the commissioners and we presented to the public is what is already widely known for years, that the Surgeon General has said there is no safe exposure to secondhand smoke," she said.