| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Hibiscus sabdariffa | Flower | 44.0 | 400.0 | -1.7 | * |
| Hordeum vulgare | Sprout Seedling | -- | 1670.0 | -0.6 | Chen, H.C. and Lin, S.M. 1988. Determination of Mineral Elements in Certain Crude Drugs (Part 1), Kaohsiung J. Med. Sci., 4: 259-272. |
| Hordeum vulgare | Seed | 100.0 | 2300.0 | -0.3 | Jim Duke's personal files.* |
| Hordeum vulgare | Stem | -- | 2250.0 | -1.1 | * |
| Houttuynia cordata | Plant | -- | 3430.0 | -0.2 | Suziki, A., Morimoto, I., and Okitzu, T., Elution of Metals from Crude Drugs, Shoykugaku Zasshi 36(3):190-195. |
| Humulus lupulus | Flower | 443.0 | 2380.0 | -0.3 | * |
| Humulus lupulus | Fruit | -- | 2380.0 | 0.1 | Pedersen, M. 1987. Nutritional Herbology. Pederson Publishing. Bountiful, Utah. 377 pp. |
| Hydrangea arborescens | Root | 567.0 | 1620.0 | -0.5 | * |
| Hydrastis canadensis | Root | 814.0 | 2940.0 | 0.2 | * |
| Hyoscyamus niger | Seed | -- | 5250.0 | 0.9 | * |
| Inula helenium | Root | 1650.0 | 7500.0 | 2.6 | * |
| Ipomoea batatas | Root | 95.0 | 710.0 | -1.0 | * |
| Ipomoea batatas | Leaf | -- | 620.0 | -1.4 | * |
| Ipomoea aquatica | Leaf | 510.0 | 3810.0 | -0.1 | * |
| Isatis tinctoria | Root | -- | 4410.0 | 1.0 | * |
| Juglans nigra | Fruit | -- | 440.0 | -0.8 | * |
| Juglans regia | Seed | 1310.0 | 1945.0 | -0.4 | * |
| Juglans cinerea | Seed | 2212.0 | 2676.0 | -0.1 | * |
| Juglans nigra | Pericarp | 53.0 | 440.0 | * | |
| Juglans nigra | Seed | 1795.0 | 2155.0 | -0.3 | * |