On 29 March 2004, the Republic of Ireland introduced a comprehensive smoke-free law, covering all indoor workplaces, including bars and restaurants. The law was not introduced in neighbouring Northern Ireland, creating a natural experiment for identifying effects of the new law.
In the BMJ study, researchers surveyed 329 staff working in rural and urban pubs in the Republic of Ireland and Northern Ireland in the six months leading up to the ban in the Republic. One year later, 249 were followed up to assess changes in exposure to secondhand smoke and respiratory symptoms.
Hours of exposure to secondhand smoke (including work, home, and other regular activities) were recorded. Details about respiratory and sensory symptoms, such as coughing, red eyes and sore throat, were taken and levels of cotinine (a by-product of nicotine) were measured.
In non-smokers, cotinine concentrations in the saliva declined significantly in both regions, but with a much greater decline in the Republic (80%) than in Northern Ireland (20%).
Work-related exposure to secondhand smoke dropped significantly in the Republic but dropped only slightly in Northern Ireland. Exposures outside work also dropped significantly in the Republic but increased in Northern Ireland, challenging the view that banning smoking in pubs and restaurants would lead to increased smoking in the home.
Furthermore, in the Republic, after the ban there was a significant drop in the proportion of bar staff experiencing respiratory symptoms.
The smoke-free workplace law in the Republic of Ireland has provided protection for one of the most heavily exposed occupational groups by reducing their exposure to secondhand smoke both in and out of the workplace, say the au
Contact: Emma Dickinson
BMJ-British Medical Journal