Bacteria, molds, and toxins in water-damaged building materials

Appl Environ Microbiol. 1997 Feb;63(2):387-93. doi: 10.1128/aem.63.2.387-393.1997.


Microbial toxins and eukaryotic cell toxicity from indoor building materials heavily colonized by fungi and bacteria were analyzed. The dominant colonizers at water-damaged sites of the building were Stachybotrys chartarum (10(3) to 10(5) visible conidia cm-2), Penicillium and Aspergillus species (10(4) CFU mg-1), gram-negative bacteria (10(4) CFU mg-1), and mycobacteria (10(3) CFU mg-1). The mycobacterial isolates were most similar to M. komossense, with 98% similarity of the complete 16S rDNA sequence. Limulus assay of water extracts prepared from a water-damaged gypsum liner revealed high contents of gram-negative endotoxin (17 ng mg-1 of E. coli lipopolysaccharide equivalents) and beta-D-glucan (210 ng mg-1 of curdlan equivalents). High-performance liquid chromatography analysis of the methanol extracts showed that the water-damaged gypsum liner also contained satratoxin (17 ng mg-1). This methanol-extracted substance was 200 times more toxic to rabbit skin and fetus feline lung cells than extract of gypsum liner sampled from a non-water-damaged site. The same extract contained toxin(s) that paralyzed the motility of boar spermatozoa at extremely low concentrations; the 50% effective concentration was 0.3 microgram of dry solids per ml. This toxicity was not explainable by the amount of bacterial endotoxin, beta-D-glucan, or satratoxin present in the same extract. The novel in vitro toxicity test that utilized boar spermatozoa as described in this article is convenient to perform and reproducible and was a useful tool for detecting toxins of microbial origin toward eukaryotic cells not detectable in building materials by the other methods.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacteria / isolation & purification
  • Bacterial Toxins / isolation & purification*
  • Cats
  • Cell Line
  • Child
  • Child Day Care Centers
  • Construction Materials*
  • Endotoxins / isolation & purification
  • Environmental Pollutants*
  • Eukaryotic Cells / drug effects
  • Fungi / isolation & purification
  • Humans
  • Male
  • Molecular Sequence Data
  • Mycotoxins / isolation & purification*
  • Rabbits
  • Spermatozoa / drug effects
  • Swine
  • Toxicity Tests
  • Water Microbiology*


  • Bacterial Toxins
  • Endotoxins
  • Environmental Pollutants
  • Mycotoxins

Associated data

  • GENBANK/Y08857