Protecting the public from exposure to secondhand cannabis smoke and vapour following legalization.

The adverse effects of direct cannabis use are well described in the literature; however, researchers are now beginning to expose the health consequences of secondhand exposure. Given the commitment by the federal government to legalize cannabis in Canada by summer 2018, public health officials must build on the successes of existing smoke-free programs and work with provinces and municipalities to develop policies that protect the public from secondhand exposure to cannabis smoke and vapour. While harmonization with existing tobacco laws may offer the simplest approach, other alternatives may allow stricter control of public consumption by different levels of government. Further research will be needed to assess the health implications of secondhand cannabis exposure, as well as the population impacts of legalization.