Question: The crawlspace in our condo has the following readings for spores/m3 : Aspergillus/Penicillium type-16000; Chaetomium- 67; Cladosporium- 227. Are these levels spores considered hazardous? It is going to cost a very high amount to have vents, sensors and spores removed to correct the situation and there is no guarantee. Please give me your comments on this.
Answer: There are no published standards for acceptable exposures to indoor mold spores. And there is no agreement among the scientific community on the exact levels of airborne indoor mold spores which are responsible for the onset of disease, nor is there adequate information on dose-effect relationship.
This is what Health Canada advises:
Health Canada considers that mould growth in residential buildings may pose a health hazard. Health risks depend on exposure and, for asthma symptoms, on allergic sensitization. However, the large number of mould species and strains growing in buildings and the large inter-individual variability in human response to mould exposure preclude the derivation of exposure limits. Therefore, Health Canada recommends:
- to control humidity and diligently repair any water damage in residences to prevent mould growth; and
- to clean thoroughly any visible or concealed mould growing in residential buildings.
These recommendations apply regardless of the mould species found to be growing in the building.
Further, in the absence of exposure limits, results from tests for the presence of fungi in air cannot be used to assess risks to the health of building occupants.”
For more information regarding mold spores please call us at 905-290-9101 in Ontario or 604-435-6555 in British Columbia.