Air and Breathing
Airborne Allergy and Air Quality
Airborne allergens and chemicals cause respiratory disease - inflammation in the nose and in the lung. Lung inflammation is often expressed as asthma. Air pollution, both indoor and outdoor, plays a significant role in the exacerbation of airway disease in asthmatics and may contribute to the overall increase in asthma morbidity.
Hospitalization for asthma has increased by 50% over the past 20 years, and deaths from asthma in the United States have increased to more than 5,000 per year. It is suggested that mortality is particularly high in lower socioeconomic groups who are exposed to higher levels of air pollution and have poorer access to early and effective medical care. Air-borne particulates may be major factor in the increasing morbidity from asthma.
In the past, medical textbooks divided asthma into inside and outside forms.
Here are the three most basic ideas about asthma causes and treatment:
Many species of molds that develop on organic materials such as fruits, grain, compost and wood can produce allergens and/or toxins that can produce respiratory disease. The main route of entry is through respiration of dust particles contaminated with the fungi or its spores. The main hazardous species belong to the families: Aspergillus, Penicillum, Cladosporium, Mucor, Stachybotrys, Absidia, Alternaria, Fusarium and Cryptostroma. The greatest risks are caused by the Aspergillus and Penicillum strains. Various strains of these families of molds have been implicated in being causative agents in asthma, hypersensitivity pneumonitis and pulmonary mycosis. See Fungi and Disease
The droppings of dust mites are important allergens which can cause asthma in sensitized people. Dust mites live in bedding, carpets, stuffed furniture, old clothing and stuffed toys. They feed on human skin shedding. Dust mites are most common in humid climates and don't survive when the humidity is below 50%. If droppings of dust mites are inhaled or come in contact with the skin, they may cause asthma and/or eczema symptoms.
Air pollution has been shown to induce attacks of asthma in exposure studies of human volunteers. Ozone is an atmospheric pollutant that enhances the effect of inhaled allergens in asthmatics, suggesting that pollutants influence lung function by increasing airway inflammation. Over 50% of the United States population lives in areas which exceed air quality standards for ozone, nitrogen dioxide, sulphur dioxide, and particulates (as monitored by the U.S. Environmental Protection Agency - EPA). Steroid bronchodilator inhalers are used to reduce chronic asthma attacks but do not protect against air pollution triggers. Avoiding inhaling polluted air remains the only effective protection. For industrial exposures special chemical filtering respirators can be worn.