Tobacco smoke exposure in public places and workplaces after smoke-free policy implementation: a longitudinal analysis of smoker cohorts in Mexico and Uruguay.

Objective: To determine the prevalence, correlates and changes in secondhand smoke (SHS) exposure over the period after comprehensive smoke-free policy implementation in two Latin American countries.

Methods: Data were analysed from population-based representative samples of adult smokers and recent quitters from the 2008 and 2010 waves of the International Tobacco Control Policy Evaluation Survey in Mexico (n = 1766 and 1840, respectively) and Uruguay (n = 1379 and 1411, respectively). Prevalence of SHS exposure was estimated for regulated venues, and generalized estimating equations were used to determine correlates of SHS exposure.

Results: Workplace SHS exposure in the last month was similar within and across countries (range: Mexico 20-25%; Uruguay 14-29%). At the most recent restaurant visit, SHS exposure was lower where comprehensive smoke-free policies were implemented (range: Uruguay 6-9%; Mexico City 5-7%) compared with Mexican cities with weaker policies, where exposure remained higher but decreased over time (32-17%). At the most recent bar visit, SHS exposure was common (range: Uruguay 8-36%; Mexico City 23-31%), although highest in jurisdictions with weaker policies (range in other Mexican cities: 74-86%). In Uruguay, males were more likely than females to be exposed to SHS across venues, as were younger compared with older smokers in Mexico.

Conclusions: Comprehensive smoke-free policies are more effective than weaker policies, although compliance in Mexico and Uruguay is not as high as desired.