The ban takes effect January 1.
Violators will face fines of up to $100. But police will only be able to hand out a citation for the offence if they've already pulled someone over for another violation, such as speeding or an illegal turn, the Associated Press reported.
Currently, Arkansas forbids smoking in vehicles when children age six and younger are present, and Louisiana doesn't allow smoking in vehicles carrying children 13 and younger.
Overall, at least 20 states and municipalities have considered limiting smoking in vehicles when children are present, the AP reported.
Second-hand smoke in cars can be up to 10 times more of a health risk than second-hand smoke in a home, according to a Harvard School of Public Health study released last year. - (Healthday)
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