For its 2004  report requested by the CDC, Damp Indoor Spaces and Health, another  Institute of Medicine committee reviewed the scientific literature to  determine the connections among damp indoor spaces, microorganisms  such as mold, and a variety of human health effects. Many Studies Associate Indoor Mold with Adverse Health Effects but Cite the Need for Additional Research

While the 2004 Institute of Medicine report, and reviews of the scientific  literature published subsequently, have found evidence associating indoor  mold with certain adverse health effects, the evidence supporting an  association between mold and other health effects remains less certain. Most of the 20 reviews of the scientific literature published from 2005 to  2007 that we examined generally agreed with the conclusions of the 2004  Institute of Medicine report. Five of the reviews we examined  contained conclusions about acute idiopathic pulmonary hemorrhage in  infants and children. However, a third review—the American Academy of  Pediatrics 2006 report—said that although a causal relationship has not  been firmly established, a variety of studies have provided some evidence  that such a relationship is plausible. Dust mites, for example, are known to cause  the development of asthma. While most of the 65 ongoing research activities involving indoor mold are  addressing asthma and critical data gaps in sampling and measurement  methods identified in the 2000 and 2004 Institute of Medicine reports,  some other important data gaps identified in the 2004 report are being  studied to a lesser degree than the gaps identified in the 2000 report. Sponsored by HHS’s  National Institute of Environmental Health Sciences, this research will  support but does not directly address the 2004 Institute of Medicine’s  recommendation for research on the relationship between mold and  dampness and acute pulmonary hemorrhage in infants. Limited Planning and Coordination of Research Activities May Affect Their Ability to Close Data Gaps on the Health Effects of Exposure to Indoor Mold

While the information on research activities relating to the health effects  of exposure to indoor mold provides some insight into the extent to which  federal agencies are addressing scientific data gaps identified by the  Institute of Medicine in 2000 and 2004, the extent to which these ongoing  research activities will effectively advance scientific knowledge in these  areas is not clear. Less than half of the agencies’ 65 ongoing research activities are  being coordinated, either within or outside their agencies. Federal agencies are not using the existing Federal Interagency  Committee on Indoor Air Quality as a forum to coordinate their  research activities on indoor mold. Federal Guidance Cites Various Adverse Health Effects of Exposure to Indoor Mold but in Some Cases Omits Less Common but Serious Effects

A majority of the 32 documents we reviewed that provide guidance to the  general public on the health effects of indoor mold in their homes—issued  by the Consumer Product Safety Commission, EPA, FEMA, HHS, and  HUD—identify asthma and upper respiratory tract symptoms as potential  health effects. Guidance on Mitigating Exposure to Indoor Mold Is Sometimes Inconsistent about Cleanup Agents and Protective Clothing and Equipment

A majority of the guidance documents we reviewed provide information to  the public about mitigating exposure to indoor mold. In its response,  EPA generally agreed with our recommendations that it use the Federal  Interagency Committee on Indoor Air Quality to, among other things, help  articulate and guide research priorities on indoor mold across relevant  federal agencies and help relevant agencies review their existing guidance  to the public on indoor mold to better ensure that it sufficiently alerts the  public about the potential adverse health effects of exposure to indoor  mold and educates the public on how to minimize exposure in homes. Specifically, we examined (1) what recent reviews of the scientific  literature have concluded about the health effects of exposure to indoor  mold; (2) the extent to which federal research addresses data gaps related  to the health effects of exposure to indoor mold; and (3) what guidance  key federal agencies are providing to the public on the health risks of  exposure to mold, and on minimizing and mitigating that exposure, and  the extent to which the guidance is consistent. To obtain information on federal research related to the health effects of  exposure to indoor mold, we conducted two surveys of officials at the  Environmental Protection Agency (EPA), the Department of Health and  Human Services (HHS), and the Department of Housing and Urban  Development (HUD) from November 2007 to May 2008. Department of Homeland Security, Federal Emergency Management  Agency, Got Mold?
Why GAO Did This Study

Recent research suggests that indoor mold poses a widespread and, for some people, serious health threat. Federal agencies engage in a number of activities to address this issue, including conducting or sponsoring research. For example, in 2004 the National Academies' Institute of Medicine issued a report requested by the Department of Health and Human Services (HHS) summarizing the scientific literature on mold, dampness, and human health. In addition, the Federal Interagency Committee on Indoor Air Quality supports the Environmental Protection Agency's (EPA) indoor air research program. With respect to the health effects of exposure to indoor mold, GAO was asked to report on (1) the conclusions of recent reviews of the scientific literature, (2) the extent to which federal research addresses data gaps, and (3) the guidance agencies are providing to the general public. GAO reviewed scientific literature on indoor mold's health effects, surveyed three agencies that conduct or sponsor indoor mold research, and analyzed guidance issued by five agencies.

What GAO Found

In general, the Institute of Medicine's 2004 report, and reviews of the scientific literature published from 2005 to 2007 that GAO examined, concluded that certain adverse health effects are more clearly associated with exposure to indoor mold than others. For example, the Institute of Medicine concluded that some respiratory effects, such as exacerbation of pre-existing asthma, are associated with exposure to indoor mold but that the available evidence was not sufficient to determine whether mold and a variety of other health effects, such as the development of asthma, cancer, and acute pulmonary hemorrhage in infants, are associated. While the reviews GAO examined generally agreed with these conclusions, a few judged the evidence for some health effects as somewhat stronger. For example, the American Academy of Pediatrics concluded in 2006 that a plausible link exists between acute pulmonary hemorrhage in infants and exposure to toxins that some molds produce. In addition, the 2004 Institute of Medicine report identified the need for additional research to address a number of data gaps related to the health effects of indoor mold. The 65 ongoing federal research activities on the health effects of exposure to indoor mold conducted or sponsored by EPA, HHS, and the Department of Housing and Urban Development (HUD) address to varying extents 15 gaps in scientific data reported by the Institute of Medicine. For example, many of the research activities address data gaps related to asthma and measurement methods, while other data gaps, such as those related to toxins produced by some molds, are being minimally addressed. Further, less than half of the ongoing mold-related research activities are coordinated either within or across agencies. This limited coordination is important in light of, among other things, the wide range of data gaps identified by the Institute of Medicine and limited federal resources. The Federal Interagency Committee on Indoor Air Quality could provide a structured mechanism for coordinating research activities on mold and other indoor air issues by, for example, serving as a forum for reviewing and prioritizing agencies' ongoing and planned research. However, it currently does not do so. Despite limitations of scientific evidence regarding a number of potential health effects of exposure to indoor mold, enough is known that federal agencies have issued guidance to the general public about health risks associated with exposure to indoor mold and how to minimize mold growth and mitigate exposure. For example, guidance issued by the Consumer Product Safety Commission, EPA, the Federal Emergency Management Agency, HHS, and HUD cites a variety of health effects of exposure to indoor mold but in some cases omits less common but serious effects. Moreover, while guidance on minimizing indoor mold growth is generally consistent, guidance on mitigating exposure to indoor mold is sometimes inconsistent about cleanup agents, protective clothing and equipment, and sensitive populations. As a result, the public may not be sufficiently advised of indoor mold's potential health risks.