Overview
ISO/TR 19601:2017 - Nanotechnologies - Aerosol generation for air exposure studies of nano-objects and their aggregates and agglomerates (NOAA) - is a technical report that describes methods for producing aerosols of nano-objects for in vivo and in vitro air exposure studies. The report helps investigators select appropriate aerosol generators to meet toxicology study designs by describing generator types, their advantages and limitations, and requirements for thorough aerosol and particle characterization. Note: ISO/TR 19601:2017 does not provide aerosolization procedures for specific nano-objects.
Key topics and technical requirements
- Scope and purpose: Guidance on producing representative, reproducible NOAA atmospheres for inhalation toxicology and exposure assessment.
- Study design considerations: Aligning generator choice with study goals, workplace exposure scenarios, existing inhalation toxicity guidelines and the Globally Harmonized System (GHS).
- Generator selection criteria: Flow-chart style decision factors including physicochemical properties of nanomaterials, handling/manufacturing exposure information, and desired exposure characteristics (size, concentration, stability).
- Types of aerosol generators covered:
- Dry dissemination (e.g., Wright dust feeder, brush generators, SSPD, fluidized bed, rotating drum, ADAGE, VAG)
- Wet dissemination (atomizers/nebulizers, electrostatic-assisted atomizers)
- Phase change (evaporation/condensation, spark generators, condensation nano-aerosols)
- Chemical-reaction sources (combustion)
- Liquid-phase filtration/dispersion techniques (critical point drying, direct injection)
- Characterization and measurement: Requirements for online and offline particle characterization (size distribution, aggregation/agglomeration state, concentration), exposure characterization, and dosing/dosimetry considerations.
- Experimental integration: Practical guidance on integrating generators with exposure chambers, dilution systems and measurement instrumentation.
- Annexes: Informative annexes on generator outputs (particle size distributions) and aerosol dilution systems.
Practical applications
- Designing and executing occupational or environmental inhalation toxicology studies for nano-objects.
- Selecting, validating and comparing aerosol generation methods for realistic exposure scenarios.
- Supporting dosimetry and risk assessment workflows, including derivation of occupational exposure limits (OEL) and reference concentrations (RfC).
- Informing laboratory procedures for both in vitro air-liquid interface exposure systems and in vivo inhalation studies.
Who should use this standard
- Toxicologists and inhalation study designers
- Nanomaterials researchers and laboratory managers
- Occupational hygienists and exposure scientists
- Regulatory bodies, standards developers and manufacturers of aerosol generation equipment
Related standards and guidance
- ISO/TS 80004 series (vocabulary for nanotechnologies: Parts 1, 2 and 4)
- Complements OECD WPMN guidance and existing inhalation toxicity frameworks
Keywords: ISO/TR 19601:2017, aerosol generation, nanotechnologies, nano-objects, NOAA, inhalation toxicology, aerosol generator, particle characterization, occupational exposure.
