Q. Can mold and dampness in my home cause congestion, fatigue, headaches, or other problems?

A. There are more than 10,000 pending lawsuits on this issue in the United States. There's little doubt about outdoor molds causing asthma. However, connecting indoor mold exposure to disease is complicated. Skin tests for mold allergies are largely unreliable. Dampness also increases the growth of bacteria and dust mites. Moisture can damage building materials to release noxious chemicals into the air. With concentrations of airborne compounds produced by molds already relatively low, how can we tell whether mold or dust mites or chemicals from building materials are causing symptoms? Finally, if both home dampness and symptoms are determined by the patient (or his or her parent), this may bias the study to showing a relationship where none exists, reducing the validity of observational studies based solely on questionnaires.

In an effort to sort this out, the Centers for Disease Control and Prevention asked the authoritative Institute of Medicine to do a comprehensive review of this issue. Looking at all studies done to date, they found that mold and other agents in damp indoor environments were associated with a 30 percent to 50 percent increase in coughing, wheezing (in previous asthmatics), and upper respiratory tract (nasal and throat) symptoms, though there was not enough data to say that mold and other agents caused these symptoms. There wasn't enough evidence to show that mold in damp indoor places caused any of the following: fatigue, shortness of breath, mucous membrane irritation syndrome, emphysema, chronic bronchitis, inhalation fevers (nonoccupational exposures), rheumatologic and other immune diseases, skin problems, the development of asthma, stomach or intestinal problems, neuropsychiatric symptoms, cancer, or reproductive problems.

So, if there's nasal congestion, then headaches could be due to sinus problems from molds, but could also be tension headaches or migraines unrelated to molds. Regardless, we should prevent dampness and mold in homes and buildings. Vent appliances that produce moisture (clothes dryers and stoves) to the outside. Open windows when bathing. Avoid carpets in bathrooms and basement, and remove indoor organic sources like plants, wood and paper. Filters on central air systems should be changed periodically, and perhaps upgraded to a medium-efficiency filter (rated at 20 percent to 50 percent). HEPA (High Efficiency Particulate Air) filters may help, but only work in a single room. Ozone generators are touted to cleanse the air of microbes but don't really work and may reduce lung function. The effectiveness of air-filtration units and electrostatic precipitators are unknown. Mold on surfaces can be removed with dishwashing soap and water. Diluted chlorine bleach kills mold but can be hazardous to use. Call the CDC at 800-438-4318 for additional information about cleaning up mold.

Dr. Landis Lum is a family- practice physician for Kaiser Permanente. Send your questions to: Prescriptions, Island Life, The Advertiser, P.O. Box 3110, Honolulu, HI 96802; islandlife@honoluluadvertiser.com; or fax 535-8170. This column is not intended to provide medical advice.