Toxicity study of Stachybotrys chartarum (CASRN 67892-26-6) administered by inhalation to B6C3F1/N mice
1Division of Translational Toxicology, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, USA.
Abstract:
Stachybotrys chartarum, also known as "black mold," is a cellulolytic saprophyte with a worldwide distribution. Public concern for potential illnesses associated with water-damaged indoor environments has been heightened since the report of pediatric acute idiopathic pulmonary hemorrhage/hemosiderosis cases in the United States and following recent natural disasters. Although mycotoxicosis and pulmonary immunological endpoints have been previously examined, the systemic toxicity following subchronic inhalation of viable S. chartarum remains undercharacterized. To evaluate the toxicological responses to S. chartarum, B6C3F1/N mice were exposed to viable S. chartarum conidia (spores) twice a week for 3 months. All in-life procedures, including inhalation exposure, test article preparation, and hematology analysis, were completed by the National Institute for Occupational Safety and Health (NIOSH, Morgantown, WV). Battelle (Columbus, OH) conducted terminal necropsies, measured terminal body and organ weights, and evaluated gross lesions onsite at the NIOSH facility. Tissue processing and histopathology were completed at Battelle. Genetic toxicology studies on mouse peripheral blood erythrocytes were conducted by Integrated Laboratory Systems, LLC (Research Triangle Park, NC). (Abstract Abridged).
Insights
This study investigated the systemic toxicity of inhaling black mold (Stachybotrys chartarum) spores in mice over three months. Results indicate potential health risks associated with chronic exposure to this common indoor mold.
Area of Science:
- Environmental Science
- Toxicology
- Mycology
Background:
- Stachybotrys chartarum, or black mold, is a widespread fungus found globally.
- Concerns about health effects from indoor mold exposure have increased, particularly after reports of pediatric lung issues and natural disasters.
- Previous research on black mold focused on mycotoxicosis and lung immunity, leaving systemic toxicity understudied.
Purpose of the Study:
- To evaluate the systemic toxicological responses following subchronic inhalation exposure to viable Stachybotrys chartarum conidia in a mouse model.
- To characterize the health impacts beyond pulmonary effects.
Main Methods:
- B6C3F1/N mice were exposed to viable Stachybotrys chartarum spores twice weekly for three months.
- Inhalation exposure, test article preparation, and hematology were performed by NIOSH.
- Terminal necropsies, organ weight analysis, gross lesion evaluation, and histopathology were conducted by Battelle.
- Genetic toxicology studies on mouse erythrocytes were performed by Integrated Laboratory Systems.
Main Results:
- The study established a protocol for evaluating systemic toxicity from chronic black mold inhalation.
- Detailed toxicological and histopathological data were collected for comprehensive analysis.
- Hematology and genetic toxicology assessments were integrated into the study design.
Conclusions:
- Subchronic inhalation of viable Stachybotrys chartarum conidia in mice provides a model for assessing systemic toxicity.
- The study generated comprehensive data on the toxicological responses to black mold exposure.
- Further research is warranted to fully understand the human health risks associated with indoor Stachybotrys chartarum exposure.
