The dangers of secondhand smoke is probably the most underestimated reality among the general population, even in developed countries. Its facts and figures need to be publicized worldwide.

Secondhand smoke (SHS) is the smoke that is exhaled by the smoker and the smoke that emanates from burning tobacco such as a burning cigarette, a burning cigar, or a burning pipe. It is also referred to as environmental tobacco smoke (ETS).

The effects of secondhand smoking (SHS) or passive smoking on our body’s health are not yet fully realized by the general population and are grossly underrated.

Passive smoking causes ill effects across most body systems and organs. It increases the risk of heart attack, stroke, middle ear infections, lung diseases, and cancer of the lungs and other organs.

During pregnancy, it harms the mother’s pregnancy and can cause premature delivery, babies with congenital defects, and even infantile death.

According to The Centers for Disease and Prevention,

There is no safe level of exposure to secondhand smoke (SHS); even brief exposure can cause immediate harm. 

Again, according to the Centers for Disease Control and Prevention (CDC), one in four nonsmokers (about 58 million people) in the United States is still exposed to secondhand smoke. This is in spite of the government’s effort of imposing restrictions on smoking in public places.

Studies indicate that secondhand smokers are more sensitive to secondhand smoke probably because of undeveloped tolerance to tobacco smoke.

Such passive smokers may be adults, men and women, children, infants, and even the fetus developing in the mother’s womb.

Though difficult to imagine, it is a fact that the effects of secondhand smoke or passive smoking are as dangerous as the effects of smoking itself.

The secondhand smoker faces the same dangers as the smoker does, meaning that inhaling secondhand smoke is equally dangerous as smoking itself.

The active smoker may have his reasons to smoke but there is no reason why you should expose your dangers to his secondhand smoke. Keep a safe distance from cigarette or cigar smoker.

According to National Institutes of Health (NIH), the minimum distance from a smoking source to prevent outdoor tobacco smoke exposure should be at least 9 meters

Effects of secondhand smoke on the health of the passive smoker

Secondhand smoke affects everybody who is exposed to it. That includes the fetus (unborn baby) in the pregnant mother’s womb, the family members in the house, coworkers in your workplace, the people in public places where smoking is permitted, and unknown bystanders near the smoker.

The dangers of secondhand smoke affect all these people who get exposed to it. Check them out below:

Risk of cancer from secondhand smoke

Secondhand smoke and the tobacco smoke inhaled by the smoker from a lit cigarette or cigar contain the same harmful chemicals and toxins. There are about 7000 chemicals in SH smoke, out of which 70 are carcinogenic.

Secondhand smoke is a known human carcinogen (cancer-forming agent) classified thus by the U.S. Environmental Protection Agency, the U.S. National Toxicology Program, the U.S. Surgeon General, and the International Agency for Research on Cancer.

It is a proven fact that smoking causes cancer and passive smoking also increases the risk when regularly exposed.

Cancer is the most publicized danger of secondhand smoking. Lung cancer is the most common with breast cancer and cervical cancer following closely behind.

A nonsmoking woman staying with a smoking man is at an additional 30 percent risk of developing lung cancer due to secondhand smoke.

The risk of developing other types of cancers is also very strong. Adults may increase the risk of breast cancer, nasal sinus cavity cancer, and nasopharyngeal cancer while in children the risk of leukemia, lymphoma, and brain tumors becomes high.

Secondhand smoke and cardiovascular disease

The risk of heart problems comes even with brief exposure to secondhand smoke. Passive smoking causes hardening and loss of flexibility in the arterial wall.

Furthermore, there is clumping together of the platelets and an increase in LDL, the bad cholesterol. Narrowing of the lumen of the arteries due to vasoconstriction and atherosclerosis greatly increases the risk of ischemic heart disease such as a heart attack. Loss of arterial flexibility and increased clotting tendency creates a double whammy that can trigger a heart attack.

This is especially true in secondhand smokers who have risk factors such s a familial history of heart disease. A nonsmoking woman staying with a smoking man has a 90% higher risk of developing heart disease.

Effects on the brain

According to the National Institute of Health, secondhand smoke has a considerable impact on the brain of the nonsmoker that is similar to that of the smoker.

Research has found that on exposure to secondhand smoke, nicotine is taken up by the nicotinic acetylcholine receptors (nAChRs) in the brain within one hour of exposure.

This explains why chronic and high secondhand smoke exposure can increase the craving for nicotine in smokers and even in nonsmokers.

According to, there is evidence that long-term exposure to SHS is linked to brain cancer in adults and children.

Effects of secondhand smoking on lungs

Secondhand smoking causes mucus to form in the airways and can cause a cough, bronchitis, bronchial asthma, pneumonia, and reduced lung function.

According to the U.S. Surgeon General, the nonsmoking individual who lives with a smoker is at a 20 to 30 percent increased risk of developing lung cancer. Tobacco smoke is responsible for about 90% of deaths due to lung cancer.

Secondhand smoking and hearing loss

Secondhand smoking has resulted in the loss of hearing due to a middle ear infection (otitis media).

SHS frequently causes ear infections in children. Smoke exposure also makes the cure of the infection more prolonged.

The back of the nose is connected to the middle ear by the Eustachian tube. Tobacco smoke, when inhaled can enter the Eustachian tube. It irritates the lining of the Eustachian tube and can lead to inflammation and swelling of the tube’s lining. This can block the tube.

Swelling and obstruction of the Eustachian tube lead to pressure imbalance in the middle ear, pain, fluid formation, and infection.

Frequent ear infections and accumulation of fluid in the middle ear are the most common causes of hearing loss in children.


Regular exposure to secondhand smoke increases the risk of senile dementia in later years after the age of 50.

Another effect on the brain that is not proven, but shows hard evidence from studies is that habitual exposure to secondhand smoke can cause cognitive impairment.

Secondhand smoke and allergy attacks

There is an increased frequency of allergic reactions among secondhand smokers. According to a study published online on October 16 in Allergy, exposure to secondhand tobacco smoke during the infancy years is linked to an increased risk of sensitivity to food allergens till the age of 6 years.

The residual secondhand smoke makes the allergy symptoms worse. If you have an existing allergy problem, SHS can make it worse and difficult to treat.

Interleukin-10 is an anti-inflammation protein, which helps to protect infants against asthma and allergy attacks. Research has shown that SH smoke is associated with low levels of interleukin-10. This increases the chances of developing an allergy.

Other studies have found that four-year-olds who were exposed to secondhand smoke during infancy were at a higher risk of developing skin and food allergy to allergens such as dust mites and animal dander.

Again, SHS inflames the lining of the airways in the lungs of the children. This makes them very prone to develop allergic bronchial asthma.

Dangers of secondhand smoke during pregnancy

Secondhand smoke affects the mother and fetus. Reading effects of smoking when pregnant will give you an insight into this problem.

If your partner is a smoker, you should not be around him and inhale his tobacco smoke during pregnancy and even otherwise.

You should ask him not to smoke in the house and when you are with him. Ideally, he should quit smoking.

How does secondhand smoke affect newborns and infants?

Secondhand smoking during pregnancy can cause premature delivery or newborns of smaller size and weight. Such babies also develop congenital abnormalities.

The smoke weakens the baby’s lungs and makes them more susceptible to infections of the ear. Such babies are at double the risk of dying of SIDS (Sudden Infant Death Syndrome).

You should make sure nobody smokes anywhere in your house without exceptions.

Secondhand smoking causes hair loss

Due to the adverse effects of passive smoking on circulation, there is improper circulation of blood and oxygen to the various parts of the body including the scalp.

An improperly nourished scalp loses its health and the hair follicles do not get the required nourishment. This leads to hair loss.

Dangers to the family

About 40% of children in the United States are regularly exposed to secondhand smoke in their own homes. This has profound short-term and long-term effects on them.

The exhaled tobacco smoke contains harmful chemicals, which include nicotine, carbon monoxide, and a range of strong human carcinogens that spread throughout your house. This exposes you, your children, and even an unborn baby in your womb to health risks.

It is not just during smoking that nonsmokers stand exposed in the house, but even over the long term.

Most of the chemicals and fine particles in secondhand smoke stick to almost all articles in the house, including your and the children’s clothes, toys, bottles, carpets, walls, furniture, and even stainless steel cooking vessels.

Over the following weeks, these pollutants are slowly released back into the air, which you and the children will breathe. This is referred to as third-hand smoke.

Children thus habitually exposed to SHS become smokers in early life. And, it is an established fact that people who start smoking early in life find it very difficult to quit smoking. These are the people who potentially exposed others to the dangers of secondhand smoke.