A Taranaki health promotion organisation is urging people to stop smoking in cars.
Tui Ora is holding a public event in Waitara today, Children's Day, encouraging people against the practice, especially around children and even with the windows down.
A health promoter, Carla Adlam, said 100,000 children were exposed to second-hand smoke in cars each week.
"You're still getting the side effects like you are a smoker, like chest infections, glue ear that sort of thing."
Ms Adlam said even when they were not in the car, they could still be affected later from toxins absorbed by the linings and upholstery.
She said some Australian states had already banned smoking in cars and New Zealand should follow suit.
Associate Health Minister Peseta Sam Lotu-Iiga said he had asked officials for advice on the issue.