| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Capsicum frutescens | Fruit | 1.0 | 1.5 | -0.3 | * |
| Capsicum annuum | Fruit | 0.05 | 5.5 | 0.9 | * |
| Carum carvi | Seed | 7.0 | 10.0 | 1.0 | * |
| Carum carvi | Fruit | -- | 7.0 | 1.3 | * |
| Carya ovata | Seed | -- | 9.8 | 1.0 | * |
| Carya illinoensis | Seed | -- | 1.6 | -0.6 | * |
| Carya ovata | Shoot | 0.25 | 23.0 | 0.1 | * |
| Carya glabra | Shoot | 0.4 | 55.0 | 1.8 | * |
| Cichorium endivia | Leaf | 2.0 | 2.4 | -0.4 | * |
| Cinnamomum burmannii | Bark | -- | -- | * | |
| Cinnamomum verum | Leaf | -- | 4.2 | -0.3 | * |
| Cinnamomum verum | Bark | -- | 1.1 | * | |
| Citrus reticulata | Fruit | 0.01 | 0.3 | -0.7 | ACTA AGRIC SCAND SUPPL 22: 1980 |
| Citrus paradisi | Fruit | 0.04 | 7.7 | 1.6 | * |
| Citrus sinensis | Fruit | 0.01 | 0.55 | -0.6 | * |
| Cocos nucifera | Seed | -- | 2.1 | -0.5 | Furr, A.K., et al. 1979 |
| Coriandrum sativum | Fruit | -- | 2.4 | -0.0 | * |
| Corylus avellana | Seed | 1.6 | 2.0 | -0.5 | * |
| Cucumis melo | Fruit | 0.87 | 1.1 | -0.4 | * |
| Cucumis sativus | Fruit | 0.01 | 1.25 | -0.4 | * |