Effects of Tobacco Smoke on Human Health

• Chemicals in Tobacco Smoke - Nicotine


  • increases heart rate and blood pressure
  • increases risk of blood cloys in the arteries, which leads to increased risk of coronary heart disease
  • increases the risk of arteries to narrow - in a pregnant mother, narrow arteries decrease the amount of food substances reaching the fetus, affecting development and may cause miscarriage
• Chemicals in Tobacco Smoke - Carbon monoxide


  • reduces the ability of blood to transport oxygen as carbon monoxide binds permanently with haemoglobin. Thus less haemoglobin is available to transport oxygen - in a pregnant mother, less oxygen reaches the fetus through the placenta which may affect fetal development
  • increases risk of coronary heart disease
• Chemicals in Tobacco Smoke - Tar


  • increases risk of cancer in the lungs as tar can cause uncontrolled cell division
  • increases risk of chronic bronchitis and emphysema as tar paralyses the cilia lining in the air passages. Dust particles become trapped in the mucus lining and cannot be removed
• Chronic Bronchitis


  • prolonged exposure to irritant particles that are found in tobacco smoke may cause chronic bronchitis
  • the epithelium lining of the air passages become inflamed
  • excessive mucus is secreted by the epithelium
  • the cilia on the epithelium become paralysed, mucus and dust particles cannot be removed
  • air passages become blocked, making breathing difficult
  • in order to breathe, persistent coughing occurs to clear the air passages, increasing the risk of lung infections
• Emphysema


  • persistant and violent coughing due to bronchitis may lead to emphysema
  • the partition walls between the alveoli break down due to persistent and violent coughing
  • decreased surface area for gaseous exchange
  • lungs lose their elasticity and become inflated with air
  • breathing becomes difficult, causing wheezing and severe breathlessness
  • when a person has chronic bronchitis and emphysema, they are said to suffer from chronic obstructive lung disease

  
• Lung Cancer


  • risk of lung cancer increases when a person smokes tobacco
  • cancer is the uncontrollable division of cells producing outgrowths or lumps of tissues
  • tobacco also increases the risk of cancers of the mouth, throat, pancreas, kidney and urinary bladder