Lung Cancer: Cigarette Smoke vs Auto Exhaust

This article claims that auto emissions account for 6-11% of lung cancers:

http://www.commondreams.org/headlines04/0603-08.htm

The report says six to 11 percent of all lung cancer cases identified in
people above 30 years of age in France are caused by automobile emissions.
"This represents 1,713 deaths a year", it says.

And this article claims the smoking accounts for and estimated 160K deaths
in 2004:

http://www.lungusa.org/site/pp.asp?c=dvLUK9O0E&b=35427

"Lung cancer is the leading cancer killer in both men and women. An
estimated 173,700 new cases of lung cancer and an estimated 160,440 deaths
from lung cancer will occur in the United States during 2004."

MY QUESTION: How can smoking account for more lung cancer deaths, when
EVERYBODY (including smokers) is exposed to auto emissions, but only smokers
are DIRECTLY exposed to cigarette smoke?

Don't you think somebody is fudging the numbers a little but? Or maybe they
really don't understand, or can't actually calculate (creatively estimate)
the supposed death toll based on the data?