Given the frequent occurrence of moisture problems in buildings and their links to respiratory problems, excessive indoor dampness should be addressed through a broad range of public health initiatives and changes in how buildings are designed, constructed, and maintained, said the committee that wrote a new report, "Damp Indoor Spaces and Health," from the Institute of Medicine of the National Academies.
"An exhaustive review of the scientific literature made it clear to us that it can be very hard to tease apart the health effects of exposure to mold from all the other factors that may be influencing health in the typical indoor environment," said committee chair Noreen Clark, dean, School of Public Health, University of Michigan, Ann Arbor. "That said, we were able to find sufficient evidence that certain respiratory problems, including symptoms in asthmatics who are sensitive to mold, are associated with exposure to mold and damp conditions. Even though the available evidence does not link mold or other factors associated with building moisture to all the serious health problems that some attribute to them, excessive indoor dampness is a widespread problem that warrants action at the local, state and national levels."
Excessive dampness influences whether mold as well as bacteria, dust mites and other such agents are present and thrive indoors. Moreover, wetness may cause chemicals and particles to be released from building materials. Many studies of health effects possibly related to indoor dampness do not distinguish the specific health effects of different biological or chemical agents.
The committee found very few studies that have examined whether mold or other factors associated with indoor dampness are linked to fatigue, neuropsychiatric disorders or other health problems that some people have attributed to fungal infestations of buildings. The little evidence that is available does not support an association, but because of the dearth of well-conducted studies and reliable data, the committee could not rule out the possibility.
Researchers made several suggestions to reduce or eliminate mold in indoor spaces:
- Training curricula on why dampness problems occur and how to prevent them should be produced and disseminated.
- Guidelines for preventing indoor dampness also should be developed at the national level to promote widespread adoption and to avoid the potential for conflicting advice from different quarters.
- Building codes and regulations should be reviewed and modified as necessary to reduce moisture problems, researchers suggested.
- Research on various means to prevent or eliminate excessive dampness -- including educational initiatives and building renovations or design changes -- should be undertaken to find out which are effective.
While there is universal agreement that promptly fixing leaks and cleaning up spills or standing water substantially reduces the potential for mold growth, there is little evidence that shows which forms of moisture control or prevention work best at reducing health problems associated with dampness, the report notes. In addition, materials designed to educate the public about the actual health risks associated with indoor dampness should be developed and evaluated. The effectiveness of economic and other incentives to spur adherence to moisture prevention practices such as bonuses for facility managers who meet defined goals for preventing or reducing problems, or fines for failure to correct problems by a specified deadline should be evaluated, and successful strategies should be implemented.
Pre-publication copies of "Damp Indoor Spaces and Health" are available from the National Academies Press; telephone: (202) 334-3313 or (800) 624-6242 or on the Internet at www.nap.edu.