| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Agrimonia eupatoria | Plant | -- | -- | Williamson, E. M. and Evans, F. J., Potter's New Cyclopaedia of Botanical Drugs and Preparations, Revised Ed., Saffron Walden, the C. W. Daniel Co., Ltd., Essex UK, 362 pp, 1988, reprint 1989. | |
| Melissa officinalis | Shoot | -- | -- | * | |
| Daucus carota | Seed | -- | -- | * | |
| Origanum vulgare | Plant | -- | -- | Abstract (See species file) | |
| Petroselinum crispum | Plant | -- | -- | List, P.H. and Horhammer, L., Hager's Handbuch der Pharmazeutischen Praxis, Vols. 2-6, Springer-Verlag, Berlin, 1969-1979. | |
| Hordeum vulgare | Leaf | -- | -- | * | |
| Schizonepeta tenuifolia | Plant | -- | -- | * |