Something in the air – Respiratory Disorders
When a film director tries to simulate a lack of oxygen in an aircraft cabin or a mining shaft, he asks the actors to desperately gulp for air and die very dramatically. The reality is different, however: you can breathe air without oxygen and not even realize that you will slowly fall asleep and die. A person only panics when the airflow is blocked or not enough air is available.
It is the oxygen that our lungs are after. About 300 million tiny air sacs in the lung, the alveoli, help the blood absorb the oxygen and dispose of the waste, carbon dioxide. An adult recycles about 10 litres of air per minute. A small child, relative to its body weight, breathes approximately three times as much. An exercising adult can exchange up to 50 litres per minute. Without a self-cleansing process, the sacs would fill very quickly with air impurities. The hair and the mucus lining in your nose should catch bacteria, dust and other intruders. But if the invader manages to sneak past, the cilia, small hair-like organs in the airways, move in a wave-like motion to convey it back to the outside. If this is not enough, you can also cough or sneeze to dislodge the foreign objects.
Heavily polluted air, however, can overwhelm the self-cleansing process, irritate the mucous membranes, or inhibit the movement of the cilia. Gases, such as ozone, bypass the self-defence mechanisms and reach the alveoli unhindered. Ozone is known to irritate and inflame the airways and possibly damages cells. Recent studies even implicate ozone with damage to the DNA.
Medical scientists are also concerned about the impact that fine airborne particles (particulate matter) has on human health. Only recently they discovered that microscopic aerosols, solid and liquid, penetrate deep into lung tissue where they can become permanently lodged. Studies of children, living in areas with air pollution, clearly associate fine particles with coughing, wheezing and bronchitis.
This shouldn’t be a surprise. City air contains up to 100 billion particles per cubic metre. But even low concentrations can trigger significant symptoms of respiratory problems. As a result, health authorities of many countries revised their national standards for particulate matter concentrations.
Bronchitis is an inflammation or irritation of the linings of the airways (bronchial tubes). The inflamed tubes swell and produce a thick layer of mucus. This restricts the airflow, makes breathing difficult and is often accompanied by a whistling sound, or wheezing. Sometimes breathing is painful and the afflicted feel tightness in their chest. The body reacts by forcing the sufferer to cough out some of the mucus.
There are two types of bronchitis: acute and chronic. Acute bronchitis is a short-term disorder. In most cases a viral infection is the cause, similar to that of the common cold and also contagious. Environmental factors are more often to blame for the longer-lasting chronic bronchitis. The ailment may plague a person for several months and even years. Smoking cigarettes is the main cause of chronic bronchitis, but long-term exposure to pollutants is also becoming a common cause. The airways have to produce additional mucus to combat the foreign substances. Coughing dislodges some of the mucus and propels it into the outside world – not a pretty sight. Coughing continues as long as the irritant is present, and the lungs are more susceptible to infection.
Because chronic bronchitis is the result of long-term exposure to irritants, it affects more people over 45. Of course, people at very high risk of developing bronchitis are smokers and those exposed to high concentrations of dust and fumes in their work environment.
The removal of the cause is the common treatment. As long as the irritant is present in the air the disease will continue. The patient must avoid polluted air and give up smoking. Medication can make some symptoms more bearable. Antibiotics reduce the impact of infections and bronchodilators open the airways.
For many people, the advent of the warm season is nothing to cheer about. Clouds of tree and grass pollen make their eyes water as if they were dicing onions and their wastepaper baskets overflow with tissues. An estimated 10-20% of population do indeed find that spring can really hang you up the most, as they suffer from seasonal rhinitis or allergic rhinitis, better known as hay fever.
Hay fever is a form of allergic rhinitis. But, while allergic rhinitis is an almost constant reaction to a particular substance (allergen), hay fever comes and goes with the seasons: the flowering seasons of trees and grasses, and the sporing seasons of fungi.
Hay fever has become epidemic with modern times. Every year, medical practitioners of many countries report an increase in consultation numbers. A better awareness amongst the population and/or an increased willingness to consult a professional explains the rising numbers.
The symptoms of hay fever are similar to those of the common cold. The intensity, however, varies greatly between individuals. For some it is just a minor nuisance, while others find their daily activities disrupted. In severe cases, the patient develops asthma.
The main symptoms are:
- Congested or runny nose
- Frequent sneezing
- Watery or red itchy eyes
- Itchy sore throat, nose or ear
- Wheezing and coughing
- Headache caused by blocked sinuses.
Because pollen and spores float easily in the air, updrafts and wind play a vital role in distributing the particles. The first warm days in spring produce vertical air currents, called thermals that carry the allergens high into the atmosphere. There they catch a ride in the prevailing winds and travel several hundred kilometers before they settle down. Therefore, you can’t necessarily blame your neighbor’s flowering ragweed for your stuffy nose.
Asthma is another burden for people in the so-called developed nations. The ‘western’ lifestyle is one of the possible causes that researchers presently investigate. Between 5% and 10% of US, Canadian, German, British and Australian citizens suffer from this debilitating and sometimes deadly disease – about half of them are children. The dramatic increase in numbers of asthma sufferers in recent years is of great concern. Throughout the world, the cases have doubled in the last 15 years, although a proportion of this increase is due to a growing awareness of the disease amongst patients and health professionals.
Weather plays an important part in the life of an asthmatic. Winds collect and spread many types of allergens over large areas. The seasons determine the type of pollens and spores in the air. Cold weather keeps you inside where you are subjected to household and pet allergens. Inversions trap pollutants that cause asthma attacks. Low humidity makes the airways wheeze even more.
A morning with blue sky and fresh, crisp air heralds the beginning of a perfect autumn day – and is another example of a ‘fine’ day that is not fine for everybody. Hospital administrators can tell you that admissions of asthma patients may double during those days. Cold air causes the bronchial tubes to constrict, making breathing more difficult.
When a cold air mass comes from the inland, it is also very likely dry. The airways of children playing outside, or of people working and exercising outdoors, also dry out very quickly and become irritated. The combination of cooling and drying of the bronchial tubes is a major trigger of severe asthma attacks.
Pollution is a factor during spring and summer. Stagnant warm air contains a variety of chemical and organic pollutants. Sulphur dioxide, nitrogen dioxide, diesel fumes, particulate matter and ozone are all associated with asthma outbreaks. Ozone, in particular, adversely affects asthmatics, sometimes at levels below a nominated ‘safe’ standard.
Asthma sufferers have two basic steps to treating their condition: remove the trigger and treat the symptoms. A multitude of medicines, mainly airways relaxants, is available to bring relief to patients. But finding the trigger is not always easy and removing it can be even more difficult, if not impossible. In addition, researchers found recently that certain circumstances, e.g. stress and obesity, aggravate asthma conditions. On the other hand, fitness and a healthy diet should help to ease the symptoms.