FEARS FOR JAILBOUND LINDSAY LOHAN'S CIGARETTE HABIT

Friends are urging Lindsay Lohan to stamp out her tobacco habit before she heads behind bars - because smoking is banned in the prison where she'll serve time, according to reports.

The actress is due to surrender to authorities on 20 July (10) to begin her 90-day sentence at the Century Regional Detention Facility in Lynwood, California.

The all-female prison, where Paris Hilton was locked up in 2007, has a zero tolerance no-smoking policy - a rule Lohan is expected to struggle with.

An unnamed pal of the star tells TMZ.com, "(Lohan is) a serious chain-smoker. The first thing she does when she wakes up is light a cigarette.

"I'm honestly scared for (Lohan)... I don't think she's gone a day without smoking in years. This isn't something she can stop overnight. It's a serious condition."

Lohan was sentenced to serve 90 days behind bars for violating the terms of her probation on a 2007 DUI arrest.