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Abstract The word "mold" is a non-scientific term that in popular parlance generally refers to members of a few dozen fila- mentous fungi. Mold growth on building surfaces not only damages these surfaces, but also affects air quality as intact spores, as well as spore and mycelial fragments, are dis- persed in the air. These can be inhaled depending on their size and concentration. Exposure to mold is associated with increased rates of respiratory disease. This document is a revision of an earlier version published by Health Canada and the Federal-Provincial Advisory Committee on Environmental and Occupational Health (CEOH) in 1995. The intent is to update the information and to reconcile certain practical aspects of the document with newer publications from the American Conference of Governmental Industrial Hygienists (ACGIH), the American Industrial Hygiene Association (AIHA) and other cognizant authorities. The purpose of this document is to assist front-line public health workers in the manage- ment of potential health risks associated with fungal con- tamination in public buildings. The report consists of two parts: 1. A review on health effects of indoor molds 2. A guide for the investigation of mold contamination in non-industrial workplaces 1. Health Effects of Indoor Molds The 1995 review concluded that ". . . epidemiological studies have consistently detected an association with res- piratory symptoms and home dampness and mold growth, but causality in these studies has not been established." The purpose of this section is to update the CEOH docu- ment by reviewing the research published from 1995 to 2001 on health effects of exposure to molds in residences and non-industrial workplaces (mostly office buildings and schools), and to determine whether the current evidence warrants more definitive conclusions. Major findings from this review are: Eight cross-sectional studies investigated the relation- ship between indoor mold and respiratory, allergic or irritation symptoms, four of which found significant association between mold exposure and either physician-diagnosed asthma or asthma-related symptoms (cough, wheezing or breathlessness). Seven case-control studies investigated the relation- ship between mold and asthma, most relying only on self-reports to assess both mold exposure and health outcomes. One of these studies found a significant association between "mold or dampness" and asthma; another found a significant association between mold and asthma but did not assess dampness; three found significant associations between mold and asthma (one of them after controlling for dampness) but not between dampness and asthma; and two found signifi- cant associations between dampness and asthma, but not between mold and asthma. To date, no cohort studies have been published on the association between residential mold exposure and asthma, although a published study has found an asso- ciation between mold exposure at school and child- hood asthma. There is presently an ongoing cohort study in Prince Edward Island, Canada. Several experimental studies with animal models exposed to fungal cells, antigens or constituents have found effects similar to those observed in humans in epidemiological studies, such as eosinophilia and increased serum IgE. Several of the studies reviewed were limited by the meth- ods used: exposure and outcome assessment based on self- reporting; no quantitative exposure assessment (and there- fore no determination of a dose–response relationship); possible confounding by other biological agents; and potential response bias. Only in a few studies reported to date has an independent effect of mold on asthma and upper respiratory health been demonstrated. Therefore, from epidemiologic data alone, it is difficult to assess the population health conse- quences of the material growth of indoor molds. It is known, however, that exposure to fungi in occupational environments causes allergic and toxic diseases. Adverse effects of fungi have also been seen in inhalation studies using animal models. Therefore, further investigation of health effects of indoor fungi using improved exposure and health outcome assessment methods is needed to resolve uncertainties. As established by the CEOH in 1995, current knowledge indicates the need to prevent damp conditions and mold growth and to remediate any fungal contamination in buildings. 2. Investigation of Fungal Contamination in the Non-Industrial Workplace It cannot be emphasized enough that the best way to man- age mold growth is to prevent it before it occurs. The essential elements of a prevention strategy are control of moisture, timely remediation of any water leakage, and adequate maintenance of heating, ventilation and air con- ditioning (HVAC) systems. Fungal Contamination in Public Buildings: Health Effects and Investigation Methods 4

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