Microbial Volatile Organic Compounds

Abstract

Microbial volatile organic compounds (MVOCs) are a variety of compounds formed in the metabolism of fungi and bacteria. Of more than 200 compounds identified as MVOCs in laboratory experiments, none can be regarded as exclusively of microbial origin or as specific for certain microbial species. Thus, the recognition of microbially contaminated areas by MVOC measurements is not successful with current methods. In this review, the basic physical and chemical properties of 96 typical MVOCs have been summarised. Of these, toxicological and exposure data were gathered for the 15 MVOCs most often analysed and reported in buildings with moisture and microbial damage. The most obvious health effect of MVOC exposure is eye and upper-airway irritation. However, in human experimental exposure studies, symptoms of irritation have appeared at MVOC concentrations several orders of magnitude higher than those measured indoors (single MVOC levels in indoor environments have ranged from a few ng/m³ up to 1 mg/m³). This is also supported by dose-dependent sensory-irritation response, as determined by the American Society for Testing and Materials mouse bioassay. On the other hand, the toxicological database is poor even for the 15 examined MVOCs. There may be more potent compounds and other endpoints not yet evaluated

Keywords:

• Health effect
• occupational exposure limit
• risk assessment
• sensory irritation
• toxicity

Acknowledgements

The authors thank the Swedish National Institute for Working Life, the Norwegian Ministry of Labour and Social Inclusion, and the Nordic Council of Ministers for financial support during the preparation of a criteria document of the Nordic Expert Group for Criteria Documentation of Health Risks from Chemicals that was originally published in the scientific serial Arbete och Hälsa 2006:13 (Korpi et al., 2006). Gunnar Johanson, Maria Albin, Karin Sørig Hougaard, Kristina Kjærheim, Vidir Kristjansson, Kai Savolainen and Vidar Skaug are acknowledged for reviewing the Nordic Expert Group criteria document, Yves Alarie for commenting on the sensory-irritation mechanism, and Inga Jakobson for literature search on physical and chemical parameters.