Effects of Air Pollution

Air pollution affects virtually all organisms because every organism depends on the atmosphere for respiration. In humans it causes irritation of the throat, nose, lungs, and eyes, produces breathing difficulty, and aggravates existing conditions such as asthma and emphysema. Contaminated air also weakens the body's general defence mechanisms, reducing its capacity to fight off other respiratory infections. Frequent exposure to polluted air raises the risk of cardiovascular disease: fine particulate matter can harden the arteries and trigger cardiac arrhythmia or even a heart attack. People who exercise outdoors are particularly vulnerable, since exercise involves deeper and faster breathing that draws in more pollutants -- which is why it is advisable to walk or jog in the morning in areas with good tree cover, when pollutant levels and temperatures are typically lower. Accidental gas leaks can be acutely lethal or sharply degrade air quality in the affected area. A particularly important mechanism is carbon monoxide's interference with oxygen transport: because haemoglobin binds carbon monoxide far more readily than oxygen, elevated CO levels starve the body's tissues of oxygen, producing headache and blurred vision at low concentrations and coma or death at high concentrati …