Terpenes are widely used by cannabis, food, and fragrance manufacturers to adjust aroma and flavor characteristics. While these compounds are often perceived as “natural,” the exact chemical composition of terpene blends placed on the market is frequently unknown or poorly documented. This lack of transparency presents a growing challenge for industrial hygienists and safety professionals tasked with evaluating worker exposure to airborne terpenes and complex terpene mixtures.
From an occupational health perspective, estimating exposure limits becomes difficult when the identity and relative concentration of individual terpenes are not fully defined. Many terpenes have different toxicological profiles, odor thresholds, and irritation potential. When present as mixed vapors, they require analytical methods capable of identifying individual compounds rather than reporting a single total hydrocarbon value.
Analytical Method for Identification of Terpenes in Air
LCS Laboratory has developed an air testing method that combines the practical sampling approach of NIOSH Method 1552 with the analytical power of Gas Chromatography–Mass Spectrometry (GC-MSD). This approach allows for separation, detection, and identification of individual terpenes in air samples. Terpenes are identified by comparing their mass spectra against the NIST spectral library integrated into the GC-MS system. The advantage of such approach that you don’t need need to tell us what terpenes we should look for. We will detect them, identify, and report their concentrations in the air.
Air Sampling and Sample Preparation
Air samples may be collected using standard charcoal sorbent tubes (SKC 226-01) or TraceAir® II diffusive samplers, following the sampling parameters outlined in NIOSH 1552. After receipt at the laboratory, terpenes are extracted from the sampling media using a proprietary solvent mixture and analyzed by GC-MSD.
This method is suitable for industrial hygiene air sampling, indoor air quality investigations, and occupational exposure assessments involving terpene emissions.
Method Validation and Detection Limits
The method was validated using a mixture of 13 terpenes commonly associated with cannabis plants and terpene formulations, including: α-pinene, β-pinene, δ-carene, α-terpinene, limonene, γ-terpinene, linalool, geraniol, α-terpineol, β-caryophyllene, humulene, valencene, and nerolidol. All compounds were successfully detected at a mass of 2 µg per sample, which represents the method detection limit.
Analytical sensitivity depends on the volume of air collected. A 50-liter active air sample collected on a charcoal tube allows terpene concentrations to be reported at approximately 40 µg/m³. Long-term sampling using a TraceAir® II diffusive sampler over a one-week period improves sensitivity to approximately 4 µg/m³, corresponding to sub-ppb terpene concentrations in air.
Applications for Industrial Hygienists and Safety Consultants
This terpene air testing method is designed for professionals involved in:
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Occupational exposure assessments
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Indoor air quality studies
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Cannabis processing facility evaluations
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Flavor and fragrance manufacturing environments
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Odor and irritation complaints related to terpene emissions
If you would like to discuss terpene air testing, sampling strategies, or method applicability to your project, please contact us by email. Our team can assist with method selection, detection limits, and interpretation of results for complex terpene mixtures.
