Respiratory system has an important role in humans. It major role is to supply the oxygen to the tissue cells and free the body from carbon dioxide that is toxic product of metabolism. Respiratory system is all the time in close contact with the surrounding atmosphere and exposed to various elements from the environment. Combining its crucial role for the normal function of the whole organism, it is designed with multiple systems that should filter inhaled air and control the humidity and temperature of it to prevent the possible damage to the sensitive inner parts of the system. Unfortunately, those mechanisms are designed for standard environmental exposures but nowadays the capacity of those protective systems is overwhelmed by different types of air pollution in modern world. Because of that, there is increase in the number of respiratory diseases worldwide and they are important health problem connected with substantial morbidity and mortality. Great efforts are involved in the prevention and treatment of those diseases.
Upper respiratory system (nose and connected passages) are exposed to the environmental factors and may be the first damaged in the case of pollution. That is called rhinitis and is defined as irritation and inflammation of the mucous membranes of the nose. Rhinitis represents a global health problem affecting 10 to 20% of the population. If the nose function of filtering, humidifying and cooling/heating the inhaled air is disturbed, the lungs are directly exposed to the same noxious factors and evidence clearly supports a link between diseases of the upper and lower airways and 10-40% of the patients with rhinitis will develop the lower respiratory system derangement.
Asthma and chronic obstructive pulmonary disease (COPD) are the main representatives. Both diseases are connected with the exposure to inhaled particles that cause allergic response in asthma or chronic inflammatory response in COPD and cause the chronic airflow limitation.
Asthma is a common, chronic respiratory disease affecting 1–18% of the population in different countries. Asthma is characterized by variable symptoms of wheeze, shortness of breath, chest tightness and/or cough, and by variable expiratory airflow limitation. Both symptoms and airflow limitation characteristically vary over time and in intensity. These variations are often triggered by factors such as allergen or irritant exposure, viral respiratory infections, change in weather or exercise. Data supporting the role of environmental risk factors for the development of asthma include a focus on: nutrition, allergens (both inhaled and ingested), pollutants (particularly environmental tobacco smoke) and microbes. Distribution of microorganisms over airborne particles of different sizes has significant implications on the human health. Exposure to outdoor pollutants, such as living near a main road, is associated with increased risk of asthma.
For sensitized patients it is advisable to avoid the direct contact to the air reach with pollen, mold or other respiratory irritants and dusts and to avoid contact with polluted environments during the seasons of viral infections.
Chronic obstructive lung disease (COPD) is another representative of major respiratory diseases. It is a leading cause of morbidity and mortality worldwide. Chronic cough and sputum production can be a first sign of the disease. The disease is characterized by the destruction of lung parenchyma, airways and pulmonary vasculature. Lungs are damaged by chronic inflammation caused by inhalation of the chronic irritants. Although the major cause of COPD is cigarette smoke, patients can develop COPD without smoking and the disease can be caused by inhalation of other noxious particles that provoke chronic inflammatory process, like outdoor, occupational and indoor air pollution and passive exposure to cigarette smoke. Asthma may also be a risk factor for the development of COPD and bronchial hyper reactivity even without a clinical diagnosis of asthma is a predictor of COPD and indicator of excess decline in lung function. The crucial step in the treatment of COPD is to stop the irritation of the respiratory system with the inhaled noxious factors.
The fact that air pollution can cause serious adverse health effects was observed in the early years of 20-th century when sudden large increase in sickness and death was connected with increase in air pollution. By the 1970s, a link between respiratory diseases and particulate air pollution was well established and there was enough evidence to support that link even at relatively low concentrations common in contemporary urban areas of the developed world. The increase was not noted only in mortality but also in the number of hospital admissions, hospital emergency room visits, and outpatient or doctor’s visits. Subjects with chronic lung diseases such as asthma or chronic bronchitis were mostly affected but increased symptoms, lower lung function, increased medication use, and higher use of hospital services were detected also among members of the general population. Air pollution from fossil fuel combustion, primarily from motor vehicle emissions in cities, is associated with decrements of respiratory function.
Reducing the risk from indoor and outdoor air pollution is feasible and requires a combination of public policy, local and national resources, cultural changes, and protective steps taken by individual patients. For all stated diseases, the essential step in the prevention and treatment is avoidance of the contact with noxious particles, allergens and infective particles in inhaled air.
Vehicle traffic and industry emit a variety of toxicants, including particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide. Urban atmospheres in modern cities carry characteristic mixtures of particulate pollution which are potentially aggravating for patients with chronic cardio-respiratory problems, and the presence of aerosolized bacteria in small size particles may have significant implications to human health. Traffic intensity, local and synoptic meteorological conditions, and degree of respiratory dysfunction correlate with the deposition of anthropogenic particles in the trachea and lungs.
Environmental interventions to reduce pollution would be ideal, but their implementation may be hampered in countries where emissions reductions are trumped by economic growth. Wearing a face masks is a simple and practical intervention for reducing individuals’ exposure to particulate air pollution. Developed as part of the biomedical response to the Spanish flu of 1919, this practice is nowadays accepted in some cultures as a best way of making a barrier against pollution. Face masks are well tolerated, and their use improves several health measures in susceptible people. Studies confirm that the use of face masks in extremely polluted cities can effectively reduce individuals’ air pollutant exposure and lower lower inflammatory and associated cardio-respiratory risks.
“There must be something sacred in salt. It is in our tears and in the ocean.” (Khalil Gibran)
Salt usually refers to sodium chloride, and the adjective for “salt” most often used in medicine is “saline”. Human life is not imaginable without a salt. Basic physiological functions depend on balance between the salts and liquids in the body.
Salt has been an essential, virtually omnipresent, part of medicine for thousands of years. It has been used as a remedy, a support treatment, and a preventive measure. It has been taken internally or applied topically and been administered in an exceedingly wide variety of forms. The ancient Egyptian papyrus recommends salt for the treatment of an infected chest wound. The healing methods of Hippocrates made frequent use of salt. Salt-based remedies were thought to have expectorant powers and Greek medicine had used salt inhalations for respiratory diseases.
In modern medicine, the precise roles of salt in the healthy and diseased human organism were scientifically investigated from the 1950s. Blood, sweat, and tears all contain salt, and both the skin and the eyes are protected from infectious germs by the anti-bacterial effect of salt. According to modern scientific research, salt does indeed have weak disinfectant properties when applied topically. Today, salt is a natural healing principle used in the form of inhalations, salt-water baths and in drinking-therapy.
Inhaling steam from salt water has become an established treatment for acute and chronic respiratory diseases. The antiseptic action of salt on the skin and mucous membranes has been known for a very long time and we know today that the anti-inflammatory effects of inhaled salt provide relief from respiratory symptoms.
Steam from salt water is inhaled in chronic diseases of the upper and lower respiratory track (pharynx, paranasal sinuses, and bronchial tree) or to ease the discomfort of a common cold. For the treatment recommended from Hippocrates now we know that salt can stimulate secretion, loosen and help eliminate viscous secretions, inhibit inflammation, reduce irritation causing cough, clean mucous membrane and clear the respiratory ducts.
Hypertonic saline solution has been shown to increase muco-ciliary clearance in normal subjects, in asthma, bronchiectasis, cystic fibrosis, and sino-nasal diseases Hypertonic saline breaks the ionic bonds within the mucus gel, thereby reducing the degree of cross-linking and entanglements and lowering the viscosity and elasticity of the mucus secretion. It can also induce an osmotic flow of water into the mucus layer, rehydrating secretions, improving mucus rheology and stimulates cilial beat via the release of prostaglandin E2. By absorbing water from the mucosa and submucosa, hypertonic saline solution can reduce edema of the airway wall in infants with acute bronchiolitis and is proven that nebulized 3% saline may significantly reduce the length of hospital stay and improve the clinical severity score in infants with acute viral bronchiolitis. Hypertonic saline inhalation can also cause sputum induction and cough, which can help to clear the sputum outside of the bronchi and thus improve airway obstruction.
Natural salt caves have been used to help relieve symptoms of chest conditions. This therapy is known as speleotherapy, where a natural salt cave climate is used as a therapy for ill health. The basis for the treatment is presence of fine aerosol elements as well as a lack of airborne pollutants and pollens. This treatment has been associated with relief of respiratory conditions such as asthma, cystic fibrosis, and COPD.
Inhalation of the dry salt particles improves many lung function parameters including forced vital capacity, forced expiratory volume in 1 second (FEV1), oxygen saturation, partial pressure of oxygen in arterial blood, and partial pressure of carbon dioxide in arterial blood. The assessment of results achieved in the investigated patients with bronchial asthma and chronic bronchitis indicates the triggering of an anti-inflammatory (including anti-allergic) mechanism. As a consequence the inflammatory process was reduced, particularly during exacerbations. These positive shifts in immunological status resulted in improved clinical symptoms, decreased need for medications, and improved their quality of life by decreasing exacerbations, reducing hospitalization, improving physical tolerance, and reducing fatigue.