Research Institute
Home | Directions | Contact Us
Biogenics Research Institute
Other Respiratory Tract Disorders
Hypersensitivity Pneumonitis
Idiopathic Intersitial Lung Disease

Indoor Contamination

Contamination within inside environments (home and workplace) at levels to potentially affect the health of occupants has been recognized to be a manifestation of personal lifestyles, climate conditions, home or building maintenance, and building materials and techniques. It is estimated that the average person in the USA spends 90% of their time indoors, mostly in the home. In some surveys 30 to 50% of homes exhibit the potential for a biological contamination. Recognized contaminants within a home include microbes (mold, bacteria, and others), animals (dogs, cats, birds, others), housedust mites, cockroaches, smoke, and chemicals.


Clinical presentations resulting from a home contamination include nuisance symptoms manifested by nasal congestion, blowing of mucous, sinus pressure aches, throat clearing and voice huskiness, hacky coughs, tiredness and fatigue, and decrease in ability to concentrate and focus. A few patients may suffer from life-altering symptoms and signs including severe, labored coughs and difficult to control asthma. Persons with fibrosis or interstitial lung diseases are experiencing life-threatening disorders.


We will discuss recognized contaminants, clinical presentations, environmental challenges, remediation of the contaminants, and long term environmental management.


Circumstances leading to a microbial contamination


Excessive moisture from any source within the home environment may lead to growth of mold and bacteria on almost any surface. Data utilized from reports of patients with hypersensitivity pneumonia help best understand factors or circumstances that may lead to dampness and a microbial contamination of sufficient severity to cause respiratory tract symptoms in humans. Cases of HP have many objective markers and methods to prove cause and effect and to demonstrate reversibility, or non-progression, of the disease with appropriate remediation.(2) Catastrophic ground water floods and major roof and plumbing leaks are clear causes of excessive moisture that may lead to mold contamination. These problems, however, are of a magnitude that they demand immediate attention before one can live within the home. Circumstances that are less obvious present more danger including minor roof leaks, "musty" basements, plumbing problems, and air conditioning condensate blockages which may be ignored by the home occupant until the contamination becomes extensive. (2, 29-31) Circumstances which are more difficult to detect depend upon the use of the home by the occupant. Excessive humidity due to lifestyles may occur without any structural problem. (32-34) Routine activity within the home including cooking, bathing, and breathing contribute to moisture levels. Standard appliances including dish washers, garbage disposals, clothes washers and dryers, and refrigerators and freezers all produce moisture. Inside animals, inside plants, aquariums, fountains, hot tubs, vaporizers, and humidifiers are often additional factors that may increase relative humidity. These moisture sources may be compounded with the improper operation of forced air heating and cooling systems that do not adequately de-humidify creating micro-environments within the home that may grow mold, eg. un-vented closets, bathrooms, and behind furniture close to walls. Recognition of these dynamics in individual homes becomes key to understanding how contaminations occur.