Passive smoking, also known as secondhand smoke, is double harmful than active smoking for many reasons. First things first, the smoke inhaled by non-smokers contains toxic chemicals, including tar, nicotine, and carbon monoxide, which are harmful to the body. While active smokers may have some control over the amount of smoke they inhale, non-smokers are more exposed to the complete range of harmful substances that is without their consent or protection.
Second-hand smoke is made up of both the smoke exhaled by the smoker and the smoke emitted from the hot tip of the cigarette. The latter, called sidestream smoke, contains higher concentrations of dangerous chemicals than mainstream smoke. Non-smokers, including children and pregnant women, are often exposed to this more dangerous form of smoke for prolonged periods in shared spaces, which leads to greater health risks.
Moreover, passive smokers typically don't build a tolerance to smoke as active smokers might. This means that their bodies are more exposed to the harmful effects, which can include respiratory issues, cardiovascular diseases, and cancer too. In fact, studies have shown that exposure to secondhand smoke can lead to many of the same diseases as active smoking, but non-smokers often don’t have the same level of common sense or prevention measures in place, making passive smoking particularly harmful and dangerous.