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Last Edited: 7/6/2012

Indoor Mold

Spores and microscopic fragments of mold growth are a natural component of both outdoor and indoor air. When a water leak or other source of moisture causes building materials or furnishings such as carpet to remain damp, mold spores that are usually in the air or dust can grow into visible mold colonies.  Scientific study over the last 10 years has found that damp buildings not only allow the growth of mold but also encourage proliferation of dust mites and cockroaches. Long-standing dampness in indoor living or working environments may increase the risk of adverse health effects, particularly respiratory problems. EHIB staff has prepared review documents summarizing available knowledge regarding the occurrence of dampness and molds and possible human health effects. This page allows access to these documents and provides links to other sites with helpful information regarding molds and other indoor air contaminants.



Fact Sheets

  • żMoho en Mi Casa: Que Hago?  --  Un sumario conciso e informativo sobre los problemas relacionados con la exposicion al moho y recomendaciones para como removerlo y prevenir su regreso....

  • Misinterpretation of Stachybotrys Serology  --  This four-page fact sheet is designed for health professionals and describes the current status (December, 2000) of biomonitoring for human exposure to the fungus Stachybotrys chartarum. There is currently no testing method that can accurately determine whether an individual has been exposed to Stachybotrys toxins or spores.

  • Stachybotrys chartarum (atra) ? a mold that may be found in water-damaged homes  --  A fact sheet designed for general audiences describing growth characteristics of the mold, Stachybotrys chartarum. Also describes possible health effects from exposure to this mold, methods to prevent occurrence and recommendations for clean-up methods.



  • Bioaerosols and Green-Waste Composting in California (06/01/1999)  --  Review of medical literature regarding biological agents and their metabolic or degradation products that are produced during the composting of yard waste (grass clippings, shrubbery, leaves, etc.). Common types, sources, exposure levels and potential health effects of biological agents such as Aspergillus fumigatus, bacterial endotoxins and thermophilic actinomycetes are described. The occurrence of these bioaerosols in the natural environment and at large municipal composting facilities is discussed.

  • Fungi and Indoor Air Quality (05/01/1996)  --  Four-page article describes types of molds commonly found indoors in home and office environments and the physical conditions that encourage their growth. Health effects that may be related to a variety of molds are discussed. Health problems including allergic, infectious and inflammatory conditions are included. Methods for preventing and controlling indoor mold contamination are reviewed.

  • Health Effects of Toxin-Producing Molds in California (04/01/1998)  --  Short article designed for health professionals describing what is known about health effects of toxin-producing molds in the indoor environment, especially Stachybotrys chartarum. This article discusses mechanism of action, route of exposure and summarizes cases from the medical literature.

  • Serious mushroom poisonings requiring hospitalization in California, 1990-94 (01/01/1996)


Related Projects

  • Indoor Air Quality in Saugus Schools  -- EHIB and EHLB IAQ staff provided technical asssitance and risk communication consultation to the Saugus Unified School District in Los Angeles County regarding classroom indoor air quality concerns.


Related Links

  • California Indoor Air Quality Program  -- This site contains useful information on a variety of indoor environmental problems including mold, radon, volatile organic compounds, asbestos, ozone, and cleaning products used indoors.

  • Pulmonary Hemorrhage/Hemosiderosis Among Infants  -- Centers for Disease Control and Prevention (CDC) report of its review and reanalysis of the 1993-1996 Cleveleand, Ohio infant lung bleeding cases that brought Stachybotrys chartarum mold to national attention. CDC concludes that exposure to this or other molds was not proven to be associated with lung bleeding in these cases.

  •  -- Homepage for the Centers for Disease Control & Prevention mold site.  Contains information on mold prevention, clean-up recommendations, what to do after a flood, and health issues associated with mold and dampness.

  • Report of the CDC Working Group on Pulmonary Hemorrhage/Hemosiderosis (1999)  (1 MB)
  • California Department of Public Health Statement on Building Dampness, Mold and Health  (682KB) -- Statement from the California Department of Public Health indicating that the presence of water damage, dampness, visible mold or old odor in schools, workplaces, residences and other indoor environments is unhealthy.

  • Fungal Glossary  -- University of Minnesota fungal glossary: short descriptions of molds/fungi commonly found indoors (Aspergillus, Penicillium, Alternaria, etc.).

  • Indoor Air Quality -- EPA  -- Information on a wide variety of indoor air contaminants, including biological (such as molds and dust mites) and chemical (such as environmental tobacco smoke, carbon monoxide, formaldehyde and others).

  • Mold Remediation in Schools and Commercial Buildings  -- April, 2001 guidance from U.S. E.P.A. on preventing, investigating, evaluating and removing or cleaning up moisture and mold problems. This document is specifically directed to schools and commercial buildings, but contains information that is helpful to home owners and renters as well.