Indoor Environmental Quality: Health Problems, Mold
Health problems associated with excessive damp conditions and mold include:
- Allergies: Allergic responses like those to pollen or animal dander are the most common types of health problems related to mold. Typical symptoms include sneezing; irritation of the nose, mouth, or throat; nasal stuffiness and runny nose; and red, itchy or watery eyes. Inhaling or touching mold or mold spores can cause a person who was not previously allergic to mold to become allergic to mold. For people with known allergies, molds can trigger asthma symptoms such as shortness of breath, wheezing, or cough. Irritation can also occur in non-allergenic (non-sensitized) people. Additionally, scientific studies indicate that exposure to molds in the workplace can make pre-existing asthma worse. Recent NIOSH investigations document that some damp buildings are associated with developing new asthma.
- Hypersensitivity pneumonitis (HP) is a kind of lung inflammation that occurs in persons who develop immune system sensitization (similar to an allergy) to inhaled organic dust. It can be mistaken for pneumonia, but it does not get better with antibiotics for infection.Symptoms of HP can vary. Some persons have shortness of breath, cough, muscle aches, chills, fever, night sweats, and profound fatigue. These symptoms usually first appear 2 to 9 hours after exposure and last for 1 to 3 days. Other affected persons have progressive shortness of breath and cough, as well as weight loss. Work-relatedness may only become apparent over long holidays if symptoms resolve and then recur on return to work. With continued exposure, the persistent lung inflammation of both kinds of symptoms can lead to scarring and permanent damage. The slow progression of symptoms and the persistence of symptoms away from work may result in delayed recognition of work-related lung disease by both workers and physicians. HP has been referred to as Bird breeder’s lung and Mushroom picker’s disease in specific occupations with a risk of HP from biological dusts. HP has been documented in workers in buildings with mold and bacteria contaminated air-conditioners (including spray-water cooling systems), and contaminated ductwork and filters. This lung disease has also occurred in workers who worked in water-damaged buildings with roof leaks, plumbing leaks, poorly draining condensation pans, and high indoor relative humidity. HP is not contagious and is due to a person’s immune system reaction to inhaled microorganisms, whether dead or alive. It is possible for workers to have both dampness-related HP and asthma at the same time. Additionally, workplaces that have workers with HP may also have workers with building-related asthma.
- Asthma is a form of lung disease in which the airways develop inflammation and bronchospasm (reversible narrowing) in response to sensitizing or irritating exposure. Affected individuals can experience episodes of shortness of breath, cough, chest tightness, and wheezing. These symptoms occur after exposure to nonspecific irritating substances in the air or after exposure to substances to which an individual is allergic. Medical testing typically reveals evidence of bronchial hyperresponsiveness such as an abnormal methacholine challenge test or reversible airways obstruction on spirometry (a test of lung function). It is important for affected individuals to have a comprehensive asthma treatment plan and regular follow-up with their physician. Early diagnosis and removal from the impacted damp office environment can cure asthma caused by workplace exposures. In approximately 15% of asthmatics, the illness may have been caused, or made worse, by workplace exposures. Some occupational exposures are well known risks for asthma development (e.g., western red cedar; isocyanates). Indoor environment research has identified evidence of an association between damp buildings and asthma symptoms in individuals with pre-existing asthma. There is also new evidence of an association between damp buildings and new-onset asthma. In an individual with new-onset asthma or worsening of stable pre-existing asthma, measurements of lung function made several times a day at work and at home over several weeks may reveal a pattern of changing lung function that suggests a workplace cause.For individuals with new-onset asthma or worsening of stable pre-existing asthma that is suspected to be related to the indoor environment, controlling or eliminating the sources of indoor contaminants, along with optimal medical treatment, may lead to symptoms of improvement or resolution.
Page last reviewed: September 1, 2015
Content source: National Institute for Occupational Safety and Health