| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Chamaemelum nobile | Plant | -- | -- | * | |
| Chenopodium ambrosioides | Plant | 440.0 | 4800.0 | 2.9 | * |
| Chrysanthemum balsamita | Plant | -- | -- | * | |
| Chrysanthemum parthenium | Shoot | -- | 15.0 | -0.1 | 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 | Plant | 3.0 | 14.0 | -0.5 | Wealth of India. |
| Cinnamomum verum | Stem Bark | -- | -- | * | |
| Cinnamomum verum | Leaf | -- | -- | Lawrence, B.M., Essential Oils 1976-1977, Essential Oils 1978, Essential Oils 1979-1980. | |
| Cinnamomum verum | Leaf Essent. Oil | -- | 2000.0 | -0.7 | * |
| Cinnamomum verum | Bark | 20.0 | 236.0 | 1.0 | * |
| Cinnamomum verum | Bark Essent. Oil | -- | 2000.0 | * | |
| Cinnamomum camphora | Plant | -- | -- | * | |
| Cinnamomum verum | Root Bark | -- | -- | * | |
| Cinnamomum aromaticum | Plant | -- | -- | * | |
| Cinnamomum aromaticum | Bark | -- | -- | Wealth of India. | |
| Cinnamomum camphora | Leaf | 140.0 | 280.0 | -0.2 | * |
| Cistus ladaniferus | Leaf | 40.0 | 31500.0 | 1.8 | * |
| Citrus paradisi | Leaf | -- | 55.0 | -0.2 | * |
| Citrus sinensis | Plant | -- | -- | * | |
| Citrus limon | Essential Oil | 40.0 | 500.0 | -0.6 | Lawrence, B.M., Essential Oils 1976-1977, Essential Oils 1978, Essential Oils 1979-1980. |
| Citrus aurantium | Leaf | -- | 1.0 | -0.2 | * |