| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Citrus reticulata | Fruit | -- | -- | * | |
| Citrus sinensis | Fruit | -- | -- | Jim Duke's personal files. | |
| Pterocarpus marsupium | Root | -- | -- | Blaschek, W., Hansel, R., Keller, K., Reichling, J., Rimpler, H., and Schneider, G. eds. 1998. Hager's Handbuch der Pharmazeutischen Praxis, Auflage Band 2 (A-K), 909 pp., (L-Z), 858 pp. Springer-Verlag, Berlin. | |
| Acacia melanoxylon | Plant | -- | -- | * |