Fungal Exposures Within the Indoor Environment

Details

• Personal Author:
  Croston T
• Description:
  Fungal contamination found within damp indoor environments negatively affects indoor air quality, and exposure to fungal bioaerosols and secondary metabolites has become an area of great public health concern. No exposure limits exist to protect occupants and workers exposed to these contaminated environments. Assessments of these environments have identified prominent fungal species proposed to contribute to health ailments, such as "Sick Building Syndrome". Associations between adverse respiratory health effects and exposure to indoor fungal contamination have been identified; however, the physiological and toxicological effects following repeated fungal inhalation exposure have not been fully characterized. An acoustical generator system delivered dry, unmodified aerosolized fungal spores to mice housed in nose-only chambers to mimic the natural route of human inhalation exposure. We used occupationally relevant doses of NTP-nominated fungal species, Aspergillus fumigatus, Stachybotrys chartarum, and Aspergillus versicolor, inhaled by the mice in order to investigate the mechanisms influencing the pulmonary immune responses following exposure. These subchronic exposure studies demonstrated that the pulmonary immune responses are characterized by differing T-cell phenotypes, as well as variable RNA expression and proteomic profiles. While A. fumigatus exposure elicited a mixed T-cell response, S. chartarum and A. versicolor elicited more of a Th2-dominate response following 13 twice-weekly exposures. Histological assessment identified pulmonary inflammation, collagen deposition and tissue remodeling following exposure to all three fungal species independently. Results suggest that the fungal component inducing immune and physiological responses vary between fungal species, such as viability or fragmentation of the fungal test article or the influence of secondary metabolites. Additional studies are warranted, including mixed fungal exposures and utilization of in vitro systems, to advance the understanding of the mechanisms that contribute to the physiological and toxicological responses that follow fungal exposure. Such studies may lead to improvements in biomarker identification, as well as the contribute to establishment of recommended exposure limits. [Description provided by NIOSH]
• Subjects:
  Air Pollution, Indoor Fungi Immune System Lung Occupational Health Respiratory System Safety Toxicology
• Keywords:
  Bioaerosols IAQ Immune Reaction Indoor Air Quality Indoor Environments Physiological Response Pulmonary System Sick Building Syndrome
• ISSN:
  1096-6080
• Document Type:
  Text
• Genre:
  Abstract or Summary
• Place as Subject:
  OSHA Region 3 ; West Virginia
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Division:
  HELD - Health Effects Laboratory Division
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  30-31
• Volume:
  180
• NIOSHTIC Number:
  nn:20062261
• Citation:
  Toxicologist 2021 Mar; 180(S1):30-31
• Federal Fiscal Year:
  2021
• Peer Reviewed:
  False
• Source Full Name:
  The Toxicologist. Society of Toxicology 60th Annual Meeting and ToxExpo, March 12-26, 2021, Virtual Event
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:8c1082e4694a2c5894d7c1aac9c1862d6c6b15fa90f4bc1f4cfe65591d0aadfa4c60ac5dc9b920cda7a66c35aaf02ab708eb331818314ae7276989dfd977ef9e
• Download URL:
  https://stacks.cdc.gov/view/cdc/225543/cdc_225543_DS1.pdf
• File Type:
  [PDF - 155.00 KB ]