Car smoking ban 'linked to reduction in teenagers' exposure to smoke' - UK study
By Jemma Crew, PA Health and Science Correspondent
The ban on smoking in cars with child passengers has been linked to a reduction of almost three-quarters in the proportion of teenagers exposed to tobacco smoke during journeys.
Researchers from London, Liverpool and Bristol analysed how often young teenagers reported travelling in a car with an adult who smoked during the journey.
The law banning smoking in cars carrying children came into force in England in October 2015 and Scotland in December the following year.
The study looked at 15,318 responses from the smoking, drinking and drug use (SDDU) surveys for 2012, 2014 and 2016 in England.
The proportion of 13 to 15-year-olds exposed to second-hand tobacco smoke fell from 6.3% in 2012 to 5.9% in 2014, and 1.6% in 2016 after the ban came into force.
After adjusting for potentially influential factors, this is an absolute reduction of 4.1 percentage points - the equivalent of a fall of almost three-quarters compared with 2014.
While the ban in Scotland did not come into force until December 2016, over the time period exposure fell from 3.4% in 2012 to 2.2% in 2014, to 1.3% in 2016.
The Scotland data was based on 822 responses to the Scottish Health Survey.
The researchers, from Imperial College London and the universities of Bristol and Liverpool, targeted 13 to 15-year-olds to avoid issues with parents reporting answers for younger children.
While an observational study, the authors say its design "permits observed changes to be plausibly ascribed to the policy intervention".
In England, they conclude: "Our results suggest that banning smoking in private vehicles carrying children has been successful in its main aim of reducing their exposure to tobacco smoke.
"Given children's known vulnerability to second-hand smoke, reductions in exposure will probably result in improved health."
The analysis is published in the journal Thorax.