Air pollution is a heterogeneous, complex mixture of gases, liquids and particulate matter (PM) that come from man-made and natural sources. The greenhouse gases — such as carbon dioxide, methane, etc. — produced from burning fossil fuel causes global warming, thus affecting us indirectly. There are, however, several environmental air pollutants that include carbon monoxide, oxides of nitrogen, sulfur dioxide, ozone, lead and PM that affect our health directly. They have a detrimental, short-term and long-term effect on our health.
Prolonged exposure to polluted air not only increases the risk of various cancers, especially lung cancer, but also overall cardiopulmonary mortality (death from heart diseases and lung diseases). Recent data from areas with high levels of industrial pollution also suggest the possibility of increased risk of babies born with heart defect.
Over the past decade, PM, which is measured as Parts Per Million (PPM), has become a major focus of research. There is irrefutable scientific data that fine particles, which often manifest as smog (smoke + fog), in our so called modern cities during winters, may be even more directly harmful. These are very fine particles and so small that they are invisible to the human eye (at less than one ten-thousandth of an inch in diameter, or no more than 2.5 micrometers across). Fine particles can contribute to the development of potentially fatal heart and lung diseases because they slip past the body’s defense shield and can be absorbed deep into the lungs and bloodstream. They are not sneezed or coughed out the way larger natural particles, such as airborne soil and sand, are removed from the body’s airways.
Moreover, these particles are usually made of harmful chemicals and can also transport gaseous pollutants with them into the lungs. They not only make us internally weak by decreasing our ability to fight infections, resulting in more respiratory infections (pneumonia), but also have grave effects on heart.
It is no surprise that hospitals see a surge in admission of patients with heart and lung problem, especially in winters, because of environmental conditions, due to the increased air pollution level. The most vulnerable population is the elderly and patients who are already having lung problems (bronchial asthma, chronic obstructive airway disease, etc) or cardiac problems (previous heart attack or angioplasty or those who have angina, heart failure, some types of heart rhythm problems).
Pollution causes heart disorders
One may also be at a greater risk from air pollution if s/he has risk factors for heart disease such as:
- Diabetes Mellitus
- High Blood Pressure (BP)
- High Blood Cholesterol
- Family history of stroke or early heart disease.
Patients may also experience exacerbation of cardiac and pulmonary symptoms, may encounter heart attack, heart failure, irregular heart beat, very high BP, stroke, etc. All these may result in more chances of a patient to die.
Several plausible mechanistic pathways have been described, including enhanced coagulation/thrombosis (tendency to form clots in blood vessels), a propensity for arrhythmias (irregular heart beat), acute arterial vasoconstriction (narrowing of blood vessels), surge in BP systemic inflammatory responses and the chronic promotion of atherosclerosis (deposition of
fat and fibrous tissue in blood vessels). All these may directly lead to acute cardiac events and the associated lung problem can either exacerbate the cardiac problem or may even precipitate it.
In the light of present evidence, it becomes necessary that steps are undertaken towards correcting this calamity when the level of ambient air pollution becomes dangerously high. Immediate practical solution could be restriction of outdoor activities for elderly persons and individuals suffering with known heart disease, pulmonary disease and diabetes mellitus. Moreover, the Simple surgical masks are not very effective. A concerted effort should be made to educate healthcare providers and at-risk patients about the potential health hazards of elevated air pollution levels.