Purpose: The authors conducted a literature review, which focused on the major classes of fungi that grow indoors and the risks of inhalation of mycotoxins from these fungi. The article addressed whether or not there is sufficient toxicologic evidence to establish a connection between indoor bioaerosol exposure and health effects.

Design: Review.

Outcome: The authors disputed the evidence supporting a relationship between inhalation exposure to mycotoxin and alleged health effects. The authors emphasized that a large number of the anecdotal reports suggesting a relationship between mycotoxins or fungi and health problems were based on ingestion rather than inhalation exposure routes. Robbins and colleagues identified numerous problems with existing animal inhalation studies, including: the small number of animals used; the subjective grading of histologic responses; the lack of controlled variables such as dosage and duration of exposure; and the non-physiologic exposure technique (e.g., injection, forced inhalation). The authors identified aflatoxins as mycotoxins produced by some, but not all species of Aspergillus. Aflatoxins have received the most attention in the scientific literature because studies have shown that they induce liver toxicity and carcinogenicity when ingested in sufficient quantities. The authors noted that inhalation of purified aflatoxin has resulted in an increased incidence of some immunologic and oncologic reactions in mice, but that there is insufficient evidence to suggest that aflatoxin is produced indoors at sufficient levels to produce any health effects in humans. The authors also reviewed several case reports suggesting a relationship between inhalation exposure to molds or mycotoxins and illness in humans. The authors stated that it is likely that mycotoxins played a part in the association between exposures to high levels of airborne molds and acute clinical illness, but there is no single mold genus that is consistently implicated in these cases. The authors also opined that the existing epidemiologic studies do not offer compelling evidence to show that mold-contaminated indoor environments result in measurable health effects. The authors suggested that it is important to identify the point at which mold contamination becomes a threat to health, since it is currently not known.

Significant Quotes: "Although evidence was found of a relationship between high levels of inhalation exposure or direct contact to mycotoxin-containing molds or mycotoxins and demonstrable… health effects in humans, the current literature does not provide compelling evidence that exposure at levels expected in most mold-contaminated indoor environments is likely to result in measurable health effects."(p. 773).

Defendants' Perspective: The review provides a compelling argument that no direct connection has been established between mycotoxin inhalation exposure and health effects. The article provides views that would be helpful for Daubert or Frye challenges.

Plaintiffs' Perspective: The authors acknowledged that inhalation exposure to mycotoxins may lead to health problems.

Peer Review: Yes.

Relevance to Ongoing Cases: The defense may use this article to challenge plaintiffs' experts claiming that mycotoxin inhalation caused illness.

How to Obtain the Article: http://www.tandf.co.uk/journals/titles/1047322x.html