About Scopulariopsis chartarum
Scopulariopsis chartarum is a dark-pigmented member of the Scopulariopsis genus found in moist indoor environments. Like S. brevicaulis, it generally needs high moisture levels to grow and is a tertiary colonizer. Elevated levels are generally associated with materials that have stayed wet, such as after a leak or a flood. A dust result cannot show whether that moisture is still present. The Scopulariopsis genus is known to be resistant to many antifungal treatments.
Ecology and water requirements
Scopulariopsis chartarum is classified as a tertiary colonizer in the ecological succession that follows water damage in indoor environments. Primary colonizers (xerophilic Penicillium and Aspergillus species) establish first on damp materials at relatively low water activity; secondary colonizers (Cladosporium) follow as moisture stabilizes; tertiary species like Scopulariopsis chartarum require sustained, high water activity (Aw 0.90 or above)[2] and typically appear after weeks to months of continuous wetness. Because of this requirement, its detection in indoor dust samples is one of the more diagnostic available signals of significant, sustained water intrusion[4], distinct from elevated humidity alone. The species cannot establish on materials that dry between wetting events; persistent water contact with cellulose-containing or other organic substrates is required.
Mycotoxin biology
Scopulariopsis chartarum produces a range of secondary metabolites with biological activity. The compounds documented in the literature for this species are listed in the chips below. Mycotoxin production is not uniform across all strains and is influenced by substrate, temperature, and water activity[3]. The same isolate may produce substantially different metabolite profiles on drywall paper versus wood versus settled dust[5]. DNA-based detection via the ERMI panel identifies species presence but does not directly measure mycotoxin presence; detection of a mycotoxin-producing species in household dust does not establish exposure to that mycotoxin at any specific concentration.
Detection in dust versus visual inspection
DNA-based detection of Scopulariopsis chartarum in settled household dust (the basis of the ERMI panel[1]) integrates spore material from current and recent growth in the home, capturing exposure history over weeks to months. A positive detection in dust does not necessarily indicate currently-active growth at the time of sampling; conversely, an active growth site can produce relatively low dust spore counts if the spores are not being aerosolized (sealed wall cavities, behind vapor barriers, or under flooring). Interpretation requires considering the dust signal alongside building inspection, occupant symptom history, and the broader pattern of species detected on the panel.
Where it’s typically found
Scopulariopsis chartarum is documented on the following substrates and locations:
- Damp building materials
- cellulose products
- damp wood and paper
- moist indoor surfaces
Mycotoxins
Compounds documented as produced by Scopulariopsis chartarum (presence and quantity vary by chemotype, strain, and substrate):
Mycotoxin production is not uniform across all strains and is influenced by substrate, temperature, and water activity. Detection of a mycotoxin-producing species in household dust does not directly establish exposure to that mycotoxin at any specific concentration.
On your ERMI report
Scopulariopsis chartarum is one of the 26 EPA water-damage indicator species used to compute the SLG1 component of the ERMI score (sometimes labeled "Group 1" in EPA documentation). Whether the level detected in any specific home is concerning depends on the broader pattern: which other species are elevated, the water-activity profile of the elevated species, the home's climate context, and (where relevant) the occupant's sensitivity history. Our interpretation report puts Scopulariopsis chartarum in that broader pattern.
Related species
References
- Vesper SJ, McKinstry C, Haugland RA, et al. Development of an Environmental Relative Moldiness Index for U.S. homes. J Occup Environ Med. 2007;49(8):829–833.
- Pitt JI, Hocking AD. Fungi and Food Spoilage. 3rd ed. New York: Springer; 2009.
- Nielsen KF. Mycotoxin production by indoor molds. Fungal Genet Biol. 2003;39(2):103–117.
- Institute of Medicine. Damp Indoor Spaces and Health. Washington, DC: National Academies Press; 2004.
- Miller JD, McMullin DR. Fungal secondary metabolites as harmful indoor air contaminants: 10 years on. Appl Microbiol Biotechnol. 2014;98(24):9953–9966.