ERMI & HERTSMI-2 Mold Testing: Research
57 papers · Curated by Lauren Lowenstein, The Biotoxin Lady
"Is my house safe?" is probably the question I get asked most. ERMI and HERTSMI-2 are how the CIRS world answers it with data instead of guesswork.
ERMI (Environmental Relative Moldiness Index) is a DNA-based dust test developed at the U.S. EPA. It uses MSQPCR to measure 36 mold species and compares your home to a national reference. HERTSMI-2 uses the same DNA data but scores just five mold species most associated with illness in CIRS patients: Aspergillus penicillioides, Aspergillus versicolor, Chaetomium globosum, Stachybotrys chartarum and Wallemia sebi.
Here's how I explain it: ERMI is like a detailed weather report, broad and comprehensive. HERTSMI-2 is like a severe weather alert, focused only on the most dangerous threats. In the Shoemaker framework, a HERTSMI-2 score under 10 generally suggests a space is low risk for someone with CIRS, while scores above 15 are considered too risky.
This hub holds about 57 research papers on ERMI, HERTSMI-2 and DNA-based mold testing: how the index was built, how it relates to asthma and health outcomes, and how it compares to air sampling and visual inspection.
One important note: these tests measure mold. They don't measure actinobacteria or endotoxins, which need their own testing.
Learn more in my ERMI & HERTSMI-2 guide, or score your own results with the free HERTSMI-2 calculator.
Educational only, not medical advice.
— Lauren Lowenstein, The Biotoxin Lady · Last reviewed October 19, 2026
Key facts
- ERMI measures 36 mold species in settled dust by MSQPCR and was developed at the U.S. EPA.
- HERTSMI-2 scores five species: A. penicillioides, A. versicolor, Chaetomium globosum, Stachybotrys chartarum and Wallemia sebi.
- HERTSMI-2 under 10 is generally considered low risk for CIRS patients, and over 15 is high risk.
- Neither test detects actinobacteria or endotoxins.
Key research papers
- Dustborne and airborne Gram-positive and Gram-negative bacteria in high versus low ERMI homes
Atin Adhikari et al. · The Science of The Total Environment · 2014
- High environmental relative moldiness index during infancy as a predictor of asthma at 7 years of age
Reponen T et al. · Annals of Allergy Asthma & Immunology · 2011
- Infant origins of childhood asthma associated with specific molds
Reponen T et al. · Journal of Allergy and Clinical Immunology · 2012
- Inside Indoor Air Quality: Environmental Relative Moldiness Index (ERMI)
Shoemaker R et al. · Filtration News · 2007
- HERTSMI-2 and ERMI: Correlating human health risk with mold specific qPCR in water-damaged buildings
David Lark et al. · Proceedings of the 14th International Conference on Indoor Air Quality and Climate · 2016
- Mycotoxin identification in moldy dwellings
Charpin-Kadouch C et al. · Journal of Applied Toxicology · 2006
- Indoor Moldy Odor Exposure and Cognitive Function in Older Adults: A Longitudinal Analysis Based on CLHLS Dataset in China
Ye Zhang et al. · Indoor Air · 2026
- Induced Production of Nitric Oxide, Tumor Necrosis Factor, and Interleukin-6 in RAW 264.7 Macrophages by Streptomycetes from Indoor Air of Moldy Houses
Hirvonen MR et al. · Archives of Environmental Health An International Journal · 1997
- Relative moldiness index as predictor of childhood respiratory illness
Vesper SJ et al. · Journal of Exposure Science & Environmental Epidemiology · 2007
- Indoor Bacterial and Fungal Burden in “Moldy” versus “Non-Moldy” Homes: A Case Study Employing Advanced Sequencing Techniques in a US Metropolitan Area
Bhavin V. Chauhan et al. · Pathogens · 2023
- Exposure to airborne microbes during the repair of moldy buildings
Rautiala S et al. · American Industrial Hygiene Association Journal · 1996
- Inflammatory responses in Raw264.7 macrophages caused by mycobacteria isolated from moldy houses
Huttunen K et al. · Environmental Toxicology and Pharmacology · 2000
- Household mold as a predictor of asthma risk: Recent progress, limitations, and future directions
Rabinovitch N · Journal of Allergy and Clinical Immunology · 2012
- Bacterial strains from moldy buildings are highly potent inducers of inflammatory and cytotoxic effects
Hirvonen MR et al. · Indoor Air · 2005
- Indoor Mold, Toxigenic Fungi, andStachybotrys chartarum: Infectious Disease Perspective
Kuhn DM et al. · Clinical Microbiology Reviews · 2003
- Role of microbial volatile compounds (mVOCs) in toxicity from molds-infested buildings: a case report
Shakil A. Saghir et al. · Archives of Clinical Toxicology · 2026
- Toxicity Screening of Fungal Extracts and Metabolites, Xenobiotic Chemicals, and Indoor Dusts with In Vitro and Ex Vivo Bioassay Methods
Tuomas Hintikka et al. · Pathogens · 2024
- Mycotoxins in crude building materials from water-damaged buildings
Tuomi T et al. · Applied and Environmental Microbiology · 2000
- Potentially pathogenic, slow-growing mycobacteria released into workplace air during the remediation of buildings
Rautiala S et al. · Journal of Occupational and Environmental Hygiene · 2004
- Efficiency of the Coriolis µ Air Sampling Device for Fungal Contamination Analysis of Indoor Air: A Case Study
Mohamad Al Hallak et al. · Pathogens · 2025
- Comparison of mycobacteria-induced cytotoxicity and inflammatory responses in human and mouse cell lines
Kati Huttunen · Inhalation Toxicology · 2001
- Protein profiles of nasal lavage fluid from individuals with work‐related upper airway symptoms associated with moldy and damp buildings
Karin Wåhlén et al. · Indoor Air · 2016
- Co-occurrence of toxic bacterial and fungal secondary metabolites in moisture-damaged indoor environments
Taubel M et al. · Indoor Air · 2011
- Interactions between and can induce apoptosis and cell cycle arrest in mouse RAW264.7 macrophages
Penttinen P et al. · Toxicology and Applied Pharmacology · 2005
- NIOSH Dampness and Mold Assessment Tool (DMAT): Documentation and Data Analysis of Dampness and Mold-Related Damage in Buildings and Its Application
Ju‐Hyeong Park et al. · Buildings · 2022
- 30+ years of knowledge creation: Indoor Air 1991–2021
William W. Nazaroff · Indoor Air · 2022
- Fungal fragments in moldy houses: a field study in homes in New Orleans and southern Ohio
Reponen T et al. · Atmospheric Environment · 2007
- Moldy environments and toxic pneumonitis
Rylander R et al. · Toxicology and Industrial Health · 2009
- Specific molds associated with asthma in water-damaged homes
Vesper SJ et al. · Journal of Occupational and Environmental Medicine · 2006
- Synergistic interaction in simultaneous exposure to Streptomyces californicus and Stachybotrys chartarum
Kati Huttunen et al. · Environmental Health Perspectives · 2004
- Toxicant-induced loss of tolerance for chemicals, foods, and drugs: assessing patterns of exposure behind a global phenomenon
Shahir Masri et al. · Environmental Sciences Europe · 2021
- Assessment of the aerosolization potential for fungal spores in moldy homes
Sivasubramani SK et al. · Indoor Air · 2004
- THIRTY YEARS OF PUBLISHED RESEARCH ON HUMAN HEALTH EFFECTS OF EXPOSURE TO THE INTERIOR ENVIRONMENT OF WATER-DAMAGED BUILT ENVIRONMENTS
Ritchie C. Shoemaker et al. · Medical Research Archives · 2025
- Environmental Sampling and Cultures
Sue M. Mietzner et al. · ClinMicroNow · 2023
- Differential effects of exposure to toxic or nontoxic mold spores on brain inflammation and Morris water maze performance
Cheryl F. Harding et al. · Behavioural Brain Research · 2023
- Tremorgenic encephalopathy: a role of mycotoxins in the production of CNS disease in humans
Garden KE et al. · Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques · 1993
- Residential indoor air quality guideline for moulds. 2007-03- 31 Canada Gazette Part I, 141(13). ERMI
Minister of Health · 2007
- A Study on Sensitivity of Soil-Based Building Mixtures to Biodeterioration by Fungi: Towards Sustainable Earth Structures
Amer Al-Jokhadar et al. · Sustainability · 2024
- Integrating Field, Laboratory and Clinical data for the IAQ investigation. Comparison of indices of human health and building healthy: SAIIE meets ERMI. Round Table, Minneapolis. R Shoemaker, S Vesper, G Boothe, G Cormier, K Lin
- Distribution of Airborne Fungi in Vehicles and Its Association with Usage Patterns
Raúl Asael Rodríguez-Villarreal et al. · Journal of Fungi · 2025
- Hypersensitivity pneumonitis from ordinary residential exposures
Apostolakos MJ et al. · Environmental Health Perspectives · 2001
- Inflammatory responses in mice after intratracheal instillation of microbes isolated from moldy buildings
Jussila JJ · STM:n Hallinnonalan avoin julkaisuarkisto (Julkari) · 2003
- Inflammatory Responses in Mice after Intratracheal Instillation of Spores of Streptomyces californicus Isolated from Indoor Air of a Moldy Building
Juha Jussila et al. · Toxicology and Applied Pharmacology · 2001
- Intranasal instillation of aflatoxin B(1) in rats: bioactivation in the nasal mucosa and neuronal transport to the olfactory bulb
Peter Larsson · Toxicological Sciences · 2000
- Developing the EPA relative moldiness index based on mold-specific quantitative PCR
Vesper S · The Synergist · 2006
- EFFECT OF GROWTH MEDIUM ON POTENTIAL OFStreptomyces AnulatusSPORES TO INDUCE INFLAMMATORY RESPONSES AND CYTOTOXICITY IN RAW264.7 MACROPHAGES
Hirvonen MR et al. · Inhalation Toxicology · 2001
- Guidelines for Public Policy Considerations in Building Standards
Ritchie Shoemaker et al. · Nutrition and Integrative Medicine for Clinicians · 2023
- Mold inhalation causes innate immune activation, neural, cognitive and emotional dysfunction
Cheryl F. Harding et al. · Brain Behavior and Immunity · 2020
- Fungal Volatile Organic Compounds: More Than Just a Funky Smell?
Arati A Inamdar et al. · Annual review of microbiology · 2020
- Chloroanisoles and Chlorophenols Explain Mold Odor but Their Impact on the Swedish Population Is Attributed to Dampness and Mold.
Johnny C Lorentzen et al. · International journal of environmental research and public health · 2020
- Fungal Signature of Moisture Damage in Buildings: Identification by Targeted and Untargeted Approaches with Mycobiome Data
Rachel I. Adams et al. · Applied and Environmental Microbiology · 2020
- Outdoor air pollution, meteorological conditions and indoor factors in dwellings in relation to sick building syndrome (SBS) among adults in China.
Chan Lu et al. · The Science of the total environment · 2016
- Observational scores of dampness and mold associated with measurements of microbial agents and moisture in three public schools.
S J Cho et al. · Indoor air · 2016
- Detection of Mycotoxins in Patients with Chronic Fatigue Syndrome
Joseph Brewer et al. · Toxins · 2013
- Dampness and moulds in workplace buildings: Associations with incidence and remission of sick building syndrome (SBS) and biomarkers of inflammation in a 10 year follow-up study
Xin Zhang et al. · The Science of The Total Environment · 2012
- Can we trust cross-sectional studies when studying the risk of moisture-related problems indoor for asthma in children?
Malin Larsson et al. · International Journal of Environmental Health Research · 2011
- Associations between Fungal Species and Water-Damaged Building Materials
Birgitte Andersen et al. · Applied and Environmental Microbiology · 2011