06/16/2015 (3) - Laserfiche WebLink

Home Browse Search

Page 110 exposure to occur, there must be a pathway from the source of the agent to the individual and the substance must also be present in a form that can gain entry to the body.28 The spore concentrations measured in the Indian River County Fire Stations are below the airborne chemical intake level (this level is known as the concentration of no toxicological concern [CoNTC], calculated with a wide margin of safety) that is predicted to be without adverse human health effects assuming a person inhales chemicals at or below this concentration over the course of their 70-year life span. The CoNTC for human exposure has been calculated to be 30 ng/m3. In the case of mold with the highest measured mycotoxin concentration per spore(and shown to grow on building materials), this CoNTC corresponds to an airborne concentration of 30,000 spores/m3, regardless of the method used to measure the mycotoxin concentration. At this concentration, no adverse effect is expected from exposure regardless of what mycotoxin any of the spores in the air might contain.29 Since the airborne spore concentrations measured at the Fire Stations are far less than 30,000 spores/m3, no adverse effect or potential hazard is expected from mycotoxin exposure at the Fire Stations. E. The term "toxic mold" is without scientific meaning because mold is not inherently toxic. "Toxic mold"is an inherently meaningless term since all substances are harmful at sufficiently large doses and all substances are harmless at sufficiently small doses. Molds such as Aspergillus sp.,Penicillium sp.,Alternaria sp., and Stachybotrys sp. are not"toxic molds"since mycotoxins are not always present in these organisms. A review of the scientific literature indicates there is agreement that mycotoxins are only sometimes produced by molds 30 and the production of toxins by many mold species is dependent on environmental growth conditions.31 The isolation of a toxigenic species does not substantiate the presence of mycotoxins.32 Mycotoxins are not volatile and do not evaporate from the mold spore or substrate particics.33 Also, recent reviews of the literature find insufficient scientific evidence to support the claim that inhalation of mycotoxins causes human disease in indoor environments. Thus, there is no basis in the scientific literature to support the use of the term "toxic mold." 2'Klaassen,C.D.(2013). loc. cit.,p.10-12. "Hardin, B.D. et al. (2009).The Concentration of No Toxicologic Concern(CoNTC)and airborne mycotoxins. J Toxicol Environ Health A.72(9): 585-598. 70 Burge,H.A. (2001).loc. cit.; Rao,C.Y.(2001).loc. cit.;Tuomi,T. et al. (2000). loc. cit. " Korpinen,E.L.and Uoti,J. (1974).Studies on Stachybotrys alternans. II.Occurrence,Morphology and Toxigenicity. Acta Pathologica,Microbiologica et Immunologica Scandinavica B.Microbiology and Immunology. 82B: 1-6.;Ren, P.et al. (1999).loc. cit.;Wyllie,T.and Morehouse,L.(1977). Wyllie,T.D.and Morehouse,L.G. Mycotoxic fungi, mycotoxins,mycotoxicoses--An encyclopedic handbook.Marcel Dekker, New York. 72 Tuomi,T.et al. (2000).loc. cit. "Schiefer, H.B.(1990).Mycotoxins in indoor air: A critical toxicological viewpoint. Proceedings of the Fifth International Conference on Indoor Air and Climate,Toronto,Canada. Indoor Air'90. 167-172.;World Health Organization. (1990). Selected Mycotoxins: Ochratoxins, Trichothecenes,Ergot,Environmental Health Criteria 105.WHO,Geneva, Switzerland. 62