| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Carya illinoensis | Seed | -- | 200.0 | -0.8 | * |
| Carya ovata | Shoot | 172.0 | 2250.0 | -1.0 | * |
| Carya glabra | Shoot | 100.0 | 4180.0 | 1.0 | * |
| Carya ovata | Seed | -- | 1180.0 | 0.7 | * |
| Caulophyllum thalictroides | Root | 0.7 | 6.3 | -0.3 | * |
| Centella asiatica | Leaf | 1.5 | 14.0 | -0.4 | * |
| Chamaemelum nobile | Flower | -- | 31.0 | 0.0 | * |
| Chondrus crispus | Plant | -- | 67.0 | -0.1 | Pedersen, M. 1987. Nutritional Herbology. Pederson Publishing. Bountiful, Utah. 377 pp. |
| Chrysanthemum parthenium | Plant | -- | 46.0 | -0.3 | * |
| Chrysanthemum parthenium | Leaf | 0.8 | 4.6 | -0.4 | * |
| Cichorium intybus | Root | -- | -- | * | |
| Cimicifuga racemosa | Root | 0.6 | 2.7 | -0.3 | * |
| Citrus reticulata | Fruit | 3.0 | 23.0 | -0.5 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Citrus paradisi | Fruit | -- | 2.0 | -0.6 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Citrus sinensis | Fruit | -- | 2.0 | -0.6 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Cnicus benedictus | Plant | -- | -- | * | |
| Cocos nucifera | Seed | -- | 370.0 | -0.6 | Furr, A.K., et al. 1979 |
| Corylus avellana | Seed | 100.0 | 900.0 | 0.3 | * |
| Crataegus laevigata | Fruit | -- | -- | * | |
| Crataegus rhipidophylla | Fruit | -- | -- | Pedersen, M. 1987. Nutritional Herbology. Pederson Publishing. Bountiful, Utah. 377 pp. |