| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Zingiber officinale | Root | -- | 2.0 | 1.3 | ANON. 1948-1976. The Wealth of India raw materials. Publications and Information Directorate, CSIR, New Delhi. 11 volumes. |
| Zingiber officinale | Rhizome | -- | 2.0 | * | |
| Vitis vinifera | Fruit | 0.1 | 0.6 | -0.7 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Vaccinium vitis-idaea | Fruit | 0.1 | 0.7 | -0.6 | * |
| Vaccinium myrtillus | Fruit | -- | 0.1 | -1.2 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Urtica dioica | Leaf | 1.4 | 7.8 | 1.3 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Symphoricarpos orbiculatus | Stem | -- | 0.264 | 2.0 | * |
| Spinacia oleracea | Leaf | 0.3 | 5.7 | 0.5 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Sorbus aucubaria | Fruit | 0.2 | 1.5 | 0.1 | * |
| Rubus chamaemorus | Fruit | 0.3 | 1.9 | 0.5 | * |
| Rosa canina | Fruit | 0.6 | 1.5 | 0.1 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Ribes rubrum | Fruit | 0.05 | 1.8 | 0.4 | * |
| Ribes nigrum | Fruit | 0.1 | 2.8 | 1.4 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Ribes uva-crispa | Fruit | 0.04 | 0.8 | -0.5 | * |
| Rhus glabra | Stem | -- | 0.134 | -0.1 | * |
| Rheum rhabarbarum | Pt | 0.1 | 4.0 | * | |
| Raphanus sativus | Root | -- | -- | * | |
| Quercus rubra | Seed | -- | 1.3 | -0.3 | * |
| Quercus phellos | Stem | -- | 0.084 | -0.9 | * |
| Quercus stellata | Stem | -- | 0.168 | 0.4 | * |