According to a new study by Centre for Addiction and Mental Health (CAMH) in Canada, large cities such as Montreal and Toronto have a smaller rate of drug and alcohol abuse than mid-size cities. In addition, cities on the Eastern and Western regions of Canada have a higher rate of drug and alcohol addiction than the central and rural areas.

The CAMH researchers list some of the possible explanations for this disparity as being the positive influence of immigrants, migration patterns within the state, availability of drugs and alcohol throughout the regions, the accessibility of treatment and local policies and culture.