STUDY: PREGNANT SMOKERS PASS CARCINOGEN TO BABY

Women who smoke while pregnant appear to pass a potent carcinogen to their
babies, researchers reported today.

The study goes beyond what scientists have known for years: Smoking by
pregnant women causes babies to be born smaller, sicklier and, in some
cases, addicted to nicotine.

"These results demonstrate a significant potential risk to the unborn child
of a woman who smokes," said Stephen Hecht of the University of Minnesota
Cancer Center, who led the new research.

Hecht analyzed the first urine samples collected from 48 babies of smokers
and nonsmokers in Germany. Hecht looked for NNK, a carcinogen found only in
tobacco products, and for byproducts of NNK after it had been processed by
the body - NNAL and NNAL-Gluc.

"We found that the positive samples were only from the newborns of mothers
who smoked," Hecht said. Of the 31 samples from mothers who smoked during
pregnancy, 22 contained NNK, NNAL or NNAL-Gluc. Babies of nonsmokers had
none of those substances in their urine, Hecht said.

The pregnant women in the two-year study smoked between 5 and 25 cigarettes
a day, averaging 12 cigarettes a day. Results showed that NNK crosses the
placental barrier between mother and fetus, where it is then broken down by
the fetus and expelled in its urine, Hecht said.

"Hopefully this will deliver the message one more time about how dangerous
it is for pregnant women to smoke," Hecht said yesterday. Only 39 percent
of smokers quit when they become pregnant, according to a 1990 study in the
American Journal of Public Health.

Hecht was reporting the findings today at the annual meeting of the
American Chemical Society in Boston. The research has not been subjected to
peer review, the usual vetting process for published studies but rarely a
part of presentations at scientific meetings.

Hecht said more research is needed to determine the likelihood of the NNK
leading to cancer in the newborns later in life.

NNK, from the family of cancer-causing substances known as nitrosamines, is
not the only carcinogen in tobacco smoke but it is especially powerful. It
can cause adenocarcinoma, a kind of lung cancer found largely in smokers.
Studies have shown that the toxin can be passed from mother to offspring in
animals.

Previous studies have shown increases in respiratory ailments among the
children of smokers, as well as other health problems. Smoking during
pregnancy also has been linked to low birth weight and other conditions.

The levels of NNK and the related chemicals found in babies in the new
study was about 10 percent of the amount of those substances found in
smokers.

Checked-by: Joel W. Johnson