According to a study of discarded tobacco packs, duty-free cigarettes are making up an increasing proportion of those smoked in New Zealand.
Otago University professor of public health Richard Edwards says about about 6% of the packs collected in the latest study were from foreign tobacco brands.
He says that is nearly double the proportion counted four years ago, and is costing the Government about $90 million a year in lost excise duty.
Professor Edwards says duty free sales should be reduced or abolished because they undermine the effect of tobacco taxes.
The anti-tobacco lobby group Action on Smoking and Health (ASH) agrees and is calling for a cold-turkey approach to duty-free cigarettes.
Health officials are looking into reducing or removing duty-free sales, at the instigation of Associate Health Minister Tariana Turia.
But ASH director Stephanie Erick says there's no research to show whether a sinking lid would be effective.
She says the Government should take the same approach as it did for smokefree prisons: just do it and then address any problems later.
Ms Erick says duty-free sales are just doing a favour for the tobacco industry, with nothing in return except poor health statistics.
Smoking rates among Pasifika remain high
A Pasifika health researcher says cheap, duty-free tobacco and cultural pressures to give gifts of cigarettes are undermining attempts to cut high smoking rates in Pasifika communities.
One in four Pasifika adults smoke, compared with the national figure of one in six.
Dr El-Shadan Tautolo of AUT University says his study into cigarette purchases by Pasifika travellers reinforces the need for duty-free sales to be abolished.
"A lot of Pasifika people, smokers and non-smokers, are purchasing tobacco when they travel. People like to take a gift for their family or friends and tobacco unfortunately seems to be the perfect gift. It's easy to transport, readily available and cheap."
Mr Tautolo says duty free tobacco allows Pasifika communities to circumvent the tobacco tax increases, and is undermining the national goal of being smokefree by 2025.