The terms secondhand or passive smoking apply to somebody who is taking in cigarette, pipe or cigar smoke without smoking themselves. If you are regularly exposed to second hand smoke, you'll face many of the same risks as smokers themselves, including cancer and dementia. Anybody may suffer if they are exposed to passive smoking, but children in particular are especially vulnerable.
The smoke that is breathed out by smokers is known as mainstream smoke, and the smoke from the cigarette's tip which is the side stream. Both are included in passive smoking, and the side stream is more harmful as it is unfiltered, and it can release 4,000 chemicals into the air1. Over fifty of these chemicals are known to cause cancer.
Secondhand smoke can linger for an hour or more even with an open window. Exposure to it is worsened in small, enclosed spaces, or if travelling in a car with somebody who smokes.
Exposure to secondhand smoke has both long- and short-term effects. In the shorter term, effects include an irritation of the throat, eyes, lungs and nose. This is caused by lingering compounds which include sulphur, ammonia and formaldehyde. Breathing conditions such as asthma and bronchitis can be triggered by passive smoking, and indeed it can also worsen their symptoms
Over a longer period of time, exposure to passive smoking can increase the risk of developing a number of conditions, including:
- Heart disease
- Cancers of the lung, breast and throat
- Chronic obstructive pulmonary disease.
Pregnant women and their unborn babies are particularly vulnerable, as are children. Exposure to secondhand smoke during pregnancy is associated with lower birth weights and an increased risk of complications during childbirth.
Living with a smoker for the first 18 months of a child's life makes them more likely to develop asthma and bronchitis and may mean they'll develop more coughs, colds and ear infections than a child from a non-smoking household.
School-age children can also suffer, and may show symptoms such as breathlessness, wheezing and phlegm.