Over the last few years a new problem has arisen that may have very important consequences for both current and future homeowners, government regulators, and real estate industry professionals. The problem is indoor mold. Although this subject is gaining increasing national media attention and has become the subject of a growing number of lawsuits, little is really known about the extent and significance of the mold problem. How widespread is the incidence of mold? Under what conditions and in what locations is it most likely to occur? What and how serious are the health problems linked to mold exposure? What can be done to combat and prevent mold infiltration into homes, apartments, and the workplace? Should health and building codes be modified to help solve the problem? These and other questions have yet to be satisfactorily addressed. One of the primary goals of this study is to try and provide some definitive answers to the above questions as they relate to the real estate industry. In doing so this research will help industry leaders formulate proactive policy initiatives that will best serve the real estate industry, as well as educate real estate professionals about how to deal with the problem of indoor mold. This, in turn, will allow them to better serve theirs customers and clients, while reducing their exposure to legal liability.
This study is based upon an extensive review of the existing literature and source material on the subject of problems with indoor mold. Our goal was to seek out the most authoritative sources of information. It includes reviews of materials from the EPA, the CDC, state and municipal agencies, major research universities, the home building, insurance, and inspection industries, medical studies, and newspaper articles. The Internet proved an invaluable source of information. Individuals identified in the literature as having expertise in this field were also contacted. One of the problems encountered in this study is that to date, despite considerable scientific and medical evidence, there is still no consensus on just how serious a health threat indoor mold represents. Nor have standards yet been developed for safe exposure levels for the various types and strains of mold encountered in homes, schools, and at the work place.
This research synthesizes the information collected for this study and provides a consensus of opinion on the mold related issues identified in the text. Although this review has been extensive, it is simply not possible to read and assess all the information that is out there on mold, a lot of which proved to be redundant. Consequently, we were forced to exercise editorial judgment as to which sources to include and cite in this study. Studies, articles, and reports that were largely opinions, contained statements or claims that had no supporting documentation, or were not based upon scientific evidence, were excluded from this report. We believe what follows is an objective assessment of the most important and reliable information currently available on the subject of mold.
II. What is Mold?
Mold is but one type of fungi or plant that exists in virtually every location across the globe. The fungi family also includes mildews, yeasts, and mushrooms. While some types of mold can cause serious health problems, other, like those found in some cheese, antibiotics, and those that break down organic material, are beneficial.
Molds reproduce by releasing spores that are commonly spread through the air and find their way into homes via windows, open doorways, and air conditioning, ventilation, and heating systems. Spores also can gain entry into homes by attaching themselves to pets, people, clothing, and shoes. Some can also be ingested.
In the U.S. there are approximately 1,000 types of mold, of which only 24 are considered potentially hazardous to people.1 Unfortunately, identifying harmful mold is made more problematic because individual mold type may have many different strains or species, some of which are more harmful than others, while other strains of the same type of mold are relatively innocuous.
Toxic molds generally refer to molds that release mycotoxins; poisonous substances found on or within mold spores that protect the spore from other types of spores and other forms of vegetation. However, there is no one agreed upon definition of what constitutes toxic mold, and many scientists view the term as alarmist, popularized most commonly by the news media and lawyers. Public health experts also point out that we should be just as concerned with mold species that release allergens. Some molds also release harmful substances known as microbial volatile organic compounds (mVOCs) that are produced by primary or secondary metabolism and become airborne. For the purposes of this study harmful mold is defined to include any mold type or strain that has been linked to health problems in humans and or structural damage to buildings and their contents.