Constituent · Monoterpene hydrocarbon
α-terpinene
α-terpinene is a light, volatile monoterpene hydrocarbon — the kind of fresh, often citrusy or piney top-note compound that evaporates fastest from an oil. Across our dataset it was measured in 52 oils (580 samples), concentrating most in Patchouli, Tea tree, Marjoram.
Essential oils richest in α-terpinene
Measured relative composition (GC peak-area %) pooled across published GC-MS samples — median, typical range (middle 50%) and the maximum seen.
| Oil | Median | Typical range | Max | Samples |
|---|---|---|---|---|
| Patchouli | 11.83% | 11.83%–11.83% | 11.83% | 1 |
| Tea tree | 7.73% | 2.75%–10.75% | 10.92% | 6 |
| Marjoram | 3% | 0.56%–6.97% | 11.7% | 35 |
| Rose | 2.9% | 2.7%–4% | 4% | 5 |
| Lemon eucalyptus | 2.73% | 2.6%–2.87% | 3% | 2 |
| Grapefruit | 1.93% | 1.67%–2.14% | 2.48% | 6 |
| Nutmeg | 1.77% | 1.23%–2.59% | 6.68% | 30 |
| Juniper | 1.6% | 0.78%–4.5% | 6% | 9 |
| Thyme | 1.28% | 0.86%–2.4% | 5.01% | 78 |
| Oregano | 1.1% | 0.7%–2.2% | 20.6% | 20 |
| Eucalyptus globulus | 1.01% | 0.77%–1.13% | 1.48% | 4 |
| Melissa | 0.82% | 0.52%–1.07% | 1.36% | 4 |
| Blue tansy | 0.79% | 0.79%–0.79% | 0.79% | 1 |
| Wormwood | 0.7% | 0.6%–0.75% | 0.8% | 3 |
| Rosemary | 0.66% | 0.5%–1.11% | 5.77% | 47 |
| Cajeput | 0.51% | 0.51%–0.51% | 0.51% | 1 |
| Black pepper | 0.5% | 0.2%–0.61% | 7.72% | 5 |
| Spearmint | 0.5% | 0.1%–0.93% | 1.02% | 4 |
| Yarrow | 0.49% | 0.27%–2.35% | 2.43% | 8 |
| Laurel | 0.41% | 0.3%–0.47% | 1% | 17 |
Oils in our library are linked above — open any profile for its full composition, safety panel and the research behind it.
Related constituents
Other monoterpene hydrocarbon compounds across the oils.
Figures are GC peak-area percentages pooled across published GC-MS samples, not concentrations, and describe chemistry — not health effects. How this is built →