| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Camellia sinensis | Seed Oil | -- | -- | * | |
| Camellia sinensis | Seed | -- | -- | * | |
| Capparis spinosa | Plant | -- | -- | * | |
| Capsicum frutescens | Seed | -- | -- | * | |
| Capsicum frutescens | Fruit | 10.0 | 82.0 | -0.3 | USDA's Ag Handbook 8 and sequelae) |
| Capsicum annuum | Fruit | 10.0 | 136.0 | -0.3 | * |
| Carica papaya | Leaf | -- | -- | Jim Duke's personal files. | |
| Carica papaya | Seed | -- | -- | * | |
| Carica papaya | Seed Oil | -- | 4000.0 | -0.6 | Jim Duke's personal files. |
| Carica papaya | Flower | -- | -- | Jim Duke's personal files. | |
| Carica papaya | Fruit | 70.0 | 627.0 | -0.2 | * |
| Carthamus tinctorius | Seed | 3000.0 | 9390.0 | -0.2 | * |
| Carum carvi | Seed | 400.0 | 444.0 | -0.3 | USDA's Ag Handbook 8 and sequelae) |
| Carum carvi | Fruit | 400.0 | 444.0 | -0.2 | * |
| Carya illinoensis | Leaf | -- | -- | * | |
| Ceiba pentandra | Seed | -- | -- | Abstract (See species file) | |
| Centaurea calcitrapa | Plant | -- | -- | * | |
| Cicer arietinum | Seed | 90.0 | 100.0 | -0.3 | USDA's Ag Handbook 8 and sequelae) |
| Cichorium intybus | Leaf | 10.0 | 204.0 | -0.6 | USDA's Ag Handbook 8 and sequelae) |
| Cichorium endivia | Leaf | 30.0 | 483.0 | -0.4 | * |