Secondhand smoke

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Children exposed to secondhand smoke at home or in the car face much greater odds of being readmitted to the hospital for asthma.  In fact, it's a two-fold increase according to a study by Cincinnati Children's Hospital Medical Center and Penn State Milton S. Hershey Children's Hospital.  Researcher's measured the blood and saliva of more than 600 children, looking for cotinine, a substance produced when the body breaks down nicotine.