Endotoxins & Bacterial Biotoxins
Understanding gram-negative bacterial contamination and how it affects indoor air quality.
What are endotoxins?
Endotoxins are toxic substances found in the cell walls of gram-negative bacteria. Unlike mold, which produces visible growth, endotoxins are invisible contaminants that can persist in dust, insulation, and HVAC systems.
Where endotoxins are found
Water-damaged buildings
Water intrusion promotes bacterial growth
HVAC systems
Contaminated ductwork and filters distribute endotoxins
Basement & crawlspace areas
High humidity creates ideal bacterial environments
Insulation & fiberglass
Dust and debris harbor bacterial colonies
Health impacts
Endotoxin exposure triggers strong inflammatory responses. Even in small quantities, endotoxins can activate immune cells and increase systemic inflammation — particularly in sensitive individuals.
Testing for endotoxins
Specialized testing like ERMI and qPCR can identify bacterial contamination. MedViro works with diagnostic professionals trained in endotoxin assessment.
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