| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Cucumis melo | Petiole | -- | -- | * | |
| Cnicus benedictus | Shoot | -- | -- | Jim Duke's personal files. | |
| Citrullus lanatus | Fruit Juice | -- | -- | * | |
| Cistus ladaniferus | Leaf | 28.0 | 1960.0 | 2.6 | * |
| Cinnamomum verum | Leaf | -- | -- | Lawrence, B.M., Essential Oils 1976-1977, Essential Oils 1978, Essential Oils 1979-1980. | |
| Cinnamomum verum | Essential Oil | -- | -- | * | |
| Cinnamomum verum | Bark Essent. Oil | -- | -- | * | |
| Cinnamomum aromaticum | Bark | -- | -- | * | |
| Cinnamomum verum | Stem Bark | -- | -- | * | |
| Cinnamomum verum | Bark | 26.0 | 104.0 | Lawrence, B.M., Essential Oils 1976-1977, Essential Oils 1978, Essential Oils 1979-1980. | |
| Cinnamomum verum | Leaf Essent. Oil | -- | 7000.0 | -1.4 | * |
| Cinnamomum verum | Plant | 26.0 | 104.0 | -0.3 | * |
| Chrysanthemum parthenium | Shoot | -- | -- | Hendriks, H., Bos, R., and Woerdenbag, H. J. 1996. The Essential Oil of Tanacetum parthenium (L.) Schultz-Bip. Flavor and Fragrance Journal 11(6): 367-71. | |
| Chrysanthemum x morifolium | Flower | -- | -- | Wealth of India. | |
| Carthamus tinctorius | Leaf | -- | 0.04 | -0.5 | * |
| Carthamus tinctorius | Bud | -- | 0.1 | * | |
| Carica papaya | Fruit | -- | 300.0 | -0.1 | * |
| Capsicum annuum | Fruit | -- | -- | * | |
| Capsicum frutescens | Fruit | -- | -- | * | |
| Cananga odorata | Flower | -- | -- | * |