Second-hand smoke is a mixture of particles and gases released from burning cigarettes or other tobacco products and exhaled smoke. It contains many known carcinogens, including benzene, formaldehyde, arsenic, cadmium and chromium.
Second-hand smoke causes lung cancer and heart disease, and worsens allergic reactions and asthma. There is some evidence it may cause laryngeal and pharyngeal cancers .
CAREX Canada estimates that approximately 418,000 Canadians are exposed to second-hand smoke at work .
Approximately 130 lung cancers, and possibly 20 suspected laryngeal cancers and 35 suspected pharyngeal cancers among non-smokers are attributed to occupational second-hand smoke exposure each year, based on 2011 cancer statistics. This amounts to 0.6% of all lung cancers, 1.6% of all laryngeal cancers, and 2.4% of all pharyngeal cancers diagnosed annually in Canada. The cost of the newly diagnosed lung cancers alone is approximately $129 million.
Most second-hand smoke-related cancers occur among workers in the manufacturing and trade sector (see pie chart).
Smoking bans are the most effective way of reducing second-hand smoke exposure . Significant progress has been made to reduce exposure to second-hand smoke in workplaces through legislation, as well as increased awareness of health effects and population-wide changes in smoking behaviour .
Despite this progress, exposure to second-hand smoke still occurs in some workplaces, such as sales and services, trades, and transportation . Further efforts are needed to strengthen and enforce smoke-free workplace legislation, especially in outdoor workplaces, and to promote smoking cessation programs to workers in all sectors.