1.   Carbon monoxide is present in all cigarette smoke and is also the poisonous gas in car exhausts.

2.   Puffs of hardened car exhaust linger in the air on busy streets.

3.   Her husband ran a pipe from her car exhaust to the bedroom in an attempt to gas her.

4.   ...car exhaust fumes.

5.   Car exhaust pollutes the air.

6.   Car exhaust has a negative effect on the environment.

7.   A US study has concluded that tiny airborne particles from car exhausts may cause disease and death even at levels that meet air pollution standards.

8.   Besides overseeing restorations, it looks for alternative preservation means, such as rerouting traffic to protect landmarks from car exhaust.

9.   But my favorite spot in the Olympics is not Hurricane Ridge, with its car exhaust and souvenirs, but the trail to Lake Angeles.

10.   Car exhaust sets off wracking coughing fits.