STUDY: BLACKS ABSORB MORE NICOTINE

Researchers' findings on smoking could help answer cancer, cessation questions

Black smokers absorb more nicotine than do white or Latino smokers, a
difference that could explain why blacks tend to suffer more from
tobacco-related disease and have more trouble kicking the habit,
researchers reported Tuesday.

The new data emerges from two studies in today's edition of the Journal of
the American Medical Association, which constitute the broadest effort ever
to understand racial differences in smoking.

``It's really important research,'' said Jack Henningfield, an expert on
nicotine addiction at Johns Hopkins University. ``It raises a whole bunch
of serious questions that need to be answered'' about the biology of
smoking and proper cessation treatment. ``The bad news is, it's 1998 and
we're just finding this out.''

African-American adults historically have smoked at higher rates than the
general population, but in recent years they have smoked at about the same
rates as other groups. More than 31 percent of black men smoke, compared
with nearly 28 percent of white men; 22.7 percent of black women smoke,
compared with 24.4 percent of white women. Since 1976, smoking rates among
black teenagers have declined dramatically, but in recent years the rate
has begun to climb again.

The two new studies focus on bloodstream levels of cotinine, the most
common chemical produced by the body from nicotine.

In the first study, researchers at the federal Centers For Disease Control
and Prevention in Atlanta measured the amount of cotinine in the blood of
7,182 subjects, 2,136 of whom said they had smoked in the previous five
days.

``For each level of cigarette smoking, the levels for African-Americans
were substantially higher,'' said lead author Ralph Caraballo of the CDC.
Black participants in the study had cotinine levels in their blood that
were between 12 percent and 50 percent higher than those of white subjects,
and 32 percent to 56 percent higher than those of Mexican-Americans.

The researchers called the results ``intriguing'' because, they wrote,
cessation experts say blacks ``are more likely to try to quit but have a
lower success rate than white smokers.'' The higher levels of cotinine
suggest that blacks absorb more nicotine from cigarettes than do whites,
enhancing the pleasure of smoking. ``This may help explain the lower
quitting success rate,'' the researchers wrote.

African-Americans are at higher risk than whites of developing lung cancer
and dying from it, the researchers noted. If the higher cotinine levels can
be linked to higher absorption of other parts of cigarette smoke, including
cancer-causing chemicals in tobacco, then ``they may help explain higher
lung cancer deaths among black smokers compared with white smokers,'' the
researchers wrote.

The researchers compensated for the fact that blacks tend to smoke fewer
cigarettes than do whites, though Caraballo said they could not take into
account possible differences in the ways that people of different races
smoke.

Previous studies have shown that black smokers tend to take more smoke into
their lungs or hold it in the lungs for a longer time. Caraballo noted that
such studies have tried to account for the greater popularity of menthol
cigarettes among blacks, and the possibility that the anesthetizing effect
of menthol ``could allow you to smoke more deeply.'' But he said the
structure of his study made such inquiries impossible.

The second study found that blacks also keep cotinine in their bodies
longer than whites do. Keeping nicotine in the body longer could enhance
smoking's pleasurable effects. Researchers at the University of
California-San Francisco studied 79 smokers and found that an
African-American who smoked 12 to 15 cigarettes a day gets as much nicotine
as whites who smoke a full pack of 20 cigarettes a day -- a difference that
Henningfield calls ``small but real,'' with important implications for
helping African-Americans quit smoking.