Staff in bars and restaurants where the policy permits or limits smoking to certain areas absorb damagingly high amounts of nicotine, finds a study in New Zealand, the first of its kind there to determine objectively whether exposure to environmental tobacco smoke (ETS) varies with smoking policy.

A significantly greater proportion of staff had a higher cotinine concentration in their saliva after a work shift when customer smoking was unrestricted (83%) or limited (40%) than staff in non-smoking establishments (13%).

Cotinine concentration increased according to the policy of the workplace (median concentration for government staff 0.15 ng/g; for staff in workplaces with a policy of no smoking 0.1 ng/g, restricted smoking 1.6 ng/g, or unrestricted smoking 1.7 ng/g). When staff in each workplace were grouped by whether their cotinine rose or not the resulting trend was significant, showing a link between fewer restrictions and increased salivary cotinine.

The study recruited staff in 29 different bars and restaurants. All were non-smokers for six months or more and were not using nicotine replacement therapy. Their workplace permitted unrestricted customer smoking (12 subjects), restricted smoking (20), or no smoking (10). To compensate for the size of the non-smoking group 50 non-smoking government workers were included as a separate category. Saliva was collected from each worker immediately before and after a work shift.

In New Zealand smoking is restricted by law in the workplace but is permitted in enclosed areas where alcohol is served. Here workers inhale high levels of ETS over long periods.