Smoking is injurious to health — there is no secret. But the fact that smoking not only affects the smokers but also non-smokers is not widely known. Secondhand smoke, also known as passive smoking, is often overlooked but it is potentially lethal to non-smokers. According to the World Health Organization (WHO), more than six lakh people die every year from secondhand smoke. A particularly upsetting fact is that a quarter of these deaths are among children. Moreover, a large percentage of the population continues to live in countries that are not covered by total smoke-free health regulations. Here are more harmful effects of secondhand smoke on everyone right from kids to women.
How does Secondhand Smoking Affect Non-Smokers
Secondhand smoke is also known as ‘environmental tobacco smoke’ or involuntary smoking. The burning of cigarettes and other tobacco products and the smoke exhaled by a smoker contributes to secondhand smoke. Exposure to secondhand smoke can occur in the workplace, home or other places such as restaurants, and parks. Passive smoking affects people of all age groups including unborn children, children, and adults.
Passive Smoking and Fetus/Pregnancy
Low Birth Weight: It is generally defined as a birth weight less than 2500g. It can result from intrauterine growth retardation (slower growth rate inside the womb) or preterm delivery. For decades it has been a known fact that decreased fetal growth has a direct link to the mother’s active smoking. The kids of active smoking mothers are 150-200g lighter in weight than those of non-smoking mothers. Majority of the studies suggest that there is a link between maternal exposure to secondhand smoke during pregnancy and reduction in birth weight.
Preterm Delivery: Pregnancy complications such as abruptio placenta (placenta detaches prematurely from the uterus), placenta previa (placenta is near the cervical opening), and premature membrane rupture may lead to preterm delivery. Pregnant women exposed to secondhand smoke are more prone to these conditions.
Other Developmental Problems: Other developmental problems that can be seen include spontaneous abortion and perinatal death. Congenital malformations and neuropsychological and physical development can also be caused by secondhand smoke.
Passive Smoking And Children
Sudden Infant Death Syndrome (SIDS): Sudden Infant Death Syndrome is characterized as a sudden and unexpected death within the first year of birth without any pre-existing health problems and without any explanations in autopsy. It has been shown that it affects boys more than girls. Research evidence suggests a causal relationship between SIDS and postnatal exposure to tobacco smoke. Chemicals in secondhand smoke affect the brain to interfere with the regulation of infants’ breathing. Infants who die from SIDS have a higher concentration of nicotine in their lungs and cotinine in their systems than those who die from other causes. There is sufficient evidence to conclude that secondhand smoke is an independent risk factor of SIDS.
Lower Respiratory Tract Infections: According to a study, lower respiratory tract infections caused around 2.74 million deaths in 2015. Most of these deaths were in children from developing nations. Lower respiratory tract infections are one of the major complications resulting from inhalation of secondhand smoke. Children below the age of two are more prone to lower respiratory tract infections. Studies show that children of parents who smoke get sick more often. Their lungs grow slower and are at risk of bronchitis and pneumonia as compared to children who are not exposed to secondhand smoke. Also, children who breathe in secondhand smoke are more prone to wheezing and coughing.
Pulmonary Problems: Studies have shown that childhood exposure to secondhand smoke reduces lung capacity in adolescents and pre-adolescents.
Chronic Respiratory Symptoms: Chronic respiratory symptoms consist of dyspnoea, wheeze, phlegm, and cough which are related to several respiratory diseases. The children of parents who smoke show an increased prevalence of respiratory symptoms, usually wheezing and cough.
Otitis Media: Otitis media or middle ear infection is another effect of secondhand smoke on children. A study suggests a causal relationship between secondhand smoke and the bacteria that causes otitis media in children.
Passive Smoking And Adults
Chronic Obstructive Pulmonary Disease: COPD is a chronic disease characterized by a chronic cough and phlegm. It also causes irreversible airflow obstruction. A 2009 study states that the impact of secondhand smoke on COPD is limited but increases steadily.
Chronic Respiratory Symptoms: Many studies have been conducted on the relationship between passive smoking and chronic respiratory symptoms in adults. The recent ones have shown that there is an increased risk of chronic respiratory symptoms due to secondhand smoke exposure at home and work.
Cancer: Smoking has been linked to cancer of the lung, oral cavity, pharynx, larynx, esophagus, pancreas, urinary bladder, nasal cavities, stomach, liver, and kidney. Secondhand smoke contains carcinogens similar to that inhaled by a smoker. Passive smoking increases the risk of developing cancer by 20-30 percent for passive smokers.
Heart Attack: Inhaling secondhand smoke disrupts the normal functioning of the vascular system and the heart, which increases the risk of a heart attack. Furthermore, breathing even a small amount of this smoke can cause the lining of the blood vessels to become thinner and also promotes stickiness of blood platelets. Noteworthily, people who already have heart disease can potentially face fatal consequences if they inhale even a small amount of secondhand smoke.
Smoking is a dangerous habit, and those who smoke are aware of the harm it may cause them. However, they need to realize the impact that passive smoking can have on their kids, friends, and family. It is imperative that passive smoking is controlled and people who smoke understand the fatal outcome for their closed ones and society at large.
(The article is reviewed by Dr. Lalit Kanodia, General Physician)
1. WHO | Worldwide burden of disease from exposure to second-hand smoke [Internet]. Who.int. 2018 [cited 27 August 2018].
2. WHO | Second-hand smoke [Internet]. Who.int. 2018 [cited 27 August 2018].
3. About secondhand smoke. Tobacco Free Initiative (TFI). The World Health Organization.
4. CDC – Fact Sheet – Health Effects of Secondhand Smoke – Smoking & Tobacco Use [Internet]. Smoking and Tobacco Use. 2018 [cited 27 August 2018].
5. Wang H, Naghavi M, Allen C, Barber R, Bhutta Z, Carter A et al. Global, regional, and national life expectancy, all-cause mortality, and cause-specific mortality for 249 causes of death, 1980–2015: a systematic analysis for the Global Burden of Disease Study 2015. The Lancet. 2016;388(10053).
6. Murphy T. Otitis Media, Bacterial Colonization, and the Smoking Parent. Clinical Infectious Diseases. 2006;42(7).
7. Eisner M. Secondhand Smoke and Obstructive Lung Disease. American Journal of Respiratory and Critical Care Medicine. 2009;179(11):973-974.