Terpenes are widely used in cannabis processing, food production, and fragrance manufacturing to shape aroma and flavor. Although often described as “natural,” commercial terpene blends are rarely chemically simple. In many cases, the exact identity and relative concentration of individual terpenes are unknown or only partially disclosed.
For industrial hygienists and air quality consultants, this creates a recurring problem: how to evaluate exposure when the mixture itself is undefined. Reporting a single “total terpene” or hydrocarbon value may obscure compounds with very different toxicological profiles, odor thresholds, and irritation potential. From an occupational health perspective, defensible exposure assessment requires identification and quantification of individual terpene components present in air.
An Analytical Approach Designed for Unknown Terpene Mixtures
LCS Laboratory developed an air testing method that combines the field practicality of NIOSH Method 1552 with GC–MS detection and identification. Rather than requiring a predefined target list, this approach allows us to detect, separate, and identify individual terpenes present in the sample, even when the composition of the mixture is not fully known in advance.
Terpene identification is based on mass spectral matching against the NIST library integrated into the GC-MS system. This means consultants do not need to specify which terpenes to analyze ahead of time. Detected compounds are identified and reported individually, along with their measured air concentrations.
This approach is particularly useful when:
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Safety Data Sheets are incomplete or vague
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Terpene formulations change between batches
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Odor or irritation complaints do not correlate with “total terpene” results
Air Sampling and Laboratory Analysis
Air samples may be collected using:
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Charcoal sorbent tubes (SKC 226-01) for active sampling, or
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TraceAir® II diffusive samplers for longer-term monitoring
Sampling parameters follow the guidance of NIOSH 1552. Upon receipt, terpenes are extracted using a proprietary solvent system and analyzed by GC-MSD.
The method is suitable for:
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Industrial hygiene exposure assessments
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Indoor air quality investigations
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Cannabis processing and extraction facilities
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Flavor and fragrance manufacturing environments
Method Validation and Sensitivity
The method was validated using a mixture of 13 terpenes commonly encountered in cannabis and formulated terpene products, including α-pinene, β-pinene, limonene, linalool, β-caryophyllene, humulene, and others.
All compounds were reliably detected at 2 µg per sample, representing the method detection limit.
Reporting limits depend on sampling strategy:
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50 L active sample: approximately 40 µg/m³
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One-week diffusive sampling (TraceAir® II): approximately 4 µg/m³, corresponding to sub-ppb terpene concentrations
This flexibility allows consultants to align sensitivity with project objectives and expected concentration ranges.
When This Method Is Most Useful
Industrial hygienists and air quality consultants typically apply this method in situations involving:
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Complex or undocumented terpene mixtures
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Worker exposure assessments in cannabis processing
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Odor, irritation, or comfort complaints
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Situations where compound-specific interpretation is required
Before You Sample
Terpene sampling is sensitive to media selection, air volume, and project goals. In many cases, small adjustments made before sampling can significantly improve data quality and interpretability.
If you would like to discuss sampling strategy, expected detection limits, or whether this method fits your project, feel free to contact us by email. We’re happy to review your approach before samples are collected. ©
