| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Agrimonia eupatoria | Shoot | -- | -- | Bisset, N.G., ed. 1994. Herbal Drugs and Phytopharmaceuticals. CRC Press. Boca Raton, FL. 566 pp. | |
| Juglans regia | Leaf | -- | -- | Bisset, N.G., ed. 1994. Herbal Drugs and Phytopharmaceuticals. CRC Press. Boca Raton, FL. 566 pp. | |
| Sanguisorba officinalis | Plant | -- | -- | * | |
| Erythroxylum coca | Leaf | -- | -- | * | |
| Eucalyptus globulus | Leaf | -- | -- | Bisset, N.G., ed. 1994. Herbal Drugs and Phytopharmaceuticals. CRC Press. Boca Raton, FL. 566 pp. | |
| Spondias pinnata | Leaf | -- | -- | * |