| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Medicago sativa | Tissue Culture | -- | -- | * | |
| Centaurea cyanus | Flower | -- | -- | Jim Duke's personal files. | |
| Equisetum hyemale | Plant | -- | -- | * | |
| Helichrysum angustifolium | Plant | -- | -- | * | |
| Rhododendron ponticum | Plant | -- | -- | * | |
| Centaurea cyanus | Shoot | -- | -- | Jim Duke's personal files. | |
| Prunus domestica | Plant | -- | -- | * | |
| Zingiber officinale | Rhizome | -- | -- | * | |
| Anethum graveolens | Fruit | -- | -- | * | |
| Eleutherococcus senticosus | Root | -- | -- | * | |
| Cinchona pubescens | Bark | -- | -- | * | |
| Chamaemelum nobile | Plant | -- | -- | * | |
| Morus alba | Plant | -- | -- | * | |
| Cinchona pubescens | Leaf | -- | -- | * | |
| Sorbus aucubaria | Fruit | -- | -- | * | |
| Calendula officinalis | Plant | -- | -- | * | |
| Cola acuminata | Plant | -- | -- | * | |
| Ficus carica | Plant | -- | -- | * | |
| Solanum melongena | Fruit | -- | -- | * | |
| Rubus idaeus | Fruit | -- | -- | Phenolic Compounds in Food and Their Effects on Health. Antioxidants & Cancer Prevention. Huang, M.T., Ho, C.T. and Lee, C.Y. eds. 1992. ACS Symposium Series 507.ACS, Washington 402 pp. |