| Plant | Low PPM | High PPM | StdDev | *Reference | |
|---|---|---|---|---|---|
| Syzygium aromaticum | Flower | 3.0 | 9.0 | -0.8 | * |
| Syzygium cumini | Fruit | 2.3 | 14.0 | 0.1 | Morton, J.F., Major Medicinal Plants. 1977. Atlas of Medicinal Plants of Middle America. Bahamas to Yucatan. 1981. |
| Symphoricarpos orbiculatus | Stem | 3.8 | 132.0 | 0.4 | * |
| Spondias tuberosa | Fruit | -- | 0.63 | -0.9 | * |
| Spondias dulcis | Fruit | -- | 0.9 | -0.9 | * |
| Spinacia oleracea | Plant | 0.1 | 24.0 | 1.1 | * |
| Sorbus aucubaria | Fruit | 0.8 | 4.0 | -0.7 | * |
| Sophora angustifolia | Root | 5.0 | 10.0 | -0.2 | * |
| Sophora subprostrata | Root | -- | 5.0 | -0.7 | * |
| Solanum tuberosum | Tuber | 0.48 | 14.0 | 0.3 | * |
| Solanum melongena | Fruit | 0.6 | 20.0 | 0.6 | * |
| Sinomenium acutum | Rhizome | -- | 16.0 | 1.2 | * |
| Sinapis alba | Seed | 6.0 | 8.0 | -0.6 | * |
| Simmondsia chinensis | Seed | -- | 10.0 | -0.4 | * |
| Siegesbeckia orientalis | Plant | 9.0 | 10.0 | -0.4 | * |
| Sesamum indicum | Plant | 14.0 | 56.0 | 4.6 | * |
| Senna obtusifolia | Seed | 9.0 | 32.0 | 1.6 | * |
| Senna occidentalis | Seed | -- | 15.0 | 0.0 | * |
| Sechium edule | Leaf | 1.8 | 10.0 | -0.5 | * |
| Secale cereale | Seed | 4.0 | 5.0 | -0.9 | USDA's Ag Handbook 8 and sequelae) |