| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Cichorium intybus | Flower | 1000.0 | 2000.0 | * | |
| Centaurea calcitrapa | Flower | -- | -- | * | |
| Cichorium intybus | Plant | -- | -- | * | |
| Cichorium intybus | Root | -- | -- | * | |
| Cichorium intybus | Leaf | -- | -- | * | |
| Centaurea cyanus | Flower | -- | -- | * | |
| Nicotiana tabacum | Leaf | -- | -- | ANON. 1948-1976. The Wealth of India raw materials. Publications and Information Directorate, CSIR, New Delhi. 11 volumes. |