| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Zingiber officinale | Rhizome | -- | -- | * | |
| Mentha pulegium | Essential Oil | -- | -- | Duke, J. A. Writeups or information summaries on approximately 2,000 economic plants, USDA, ARS, Beltsville, MD 20705. | |
| Ocimum basilicum | Shoot Essent. Oil | -- | 1700.0 | * | |
| Boswellia sacra | Resin Essent. Oil | -- | 600000.0 | Abdel Wahab, S. M., Aboutabl, E. A., El-Zalabani, S. M., Fouad, H. A., De Pooter, H. L., El-Fallaha, B. 1987. The Essential Oil of Olibanum. Plant Med. 53 (4): 382-384. |