Table 5.
Levels of Metals in Kratom Products.
| Product # | Metal Concentration (μg/g Raw Kratom Product) | ||||||
|---|---|---|---|---|---|---|---|
| As | Cd | Cr | Fe | Hg | Ni | Pb | |
| 1 | 0.24 | 0.029 | 3.9 | 348 | 0.018 | 2.4 | 0.32 |
| 1A | 0.24 | 0.043 | 2.6 | 420 | 0.012 | 2.8 | 0.40 |
| 2 | 0.09 | 0.028 | 1.6 | 187 | 0.009 | 1.0 | 0.16 |
| 2A | 0.22 | 0.024 | 2.2 | 460 | 0.013 | 3.0 | 0.53 |
| 3 | 0.20 | 0.028 | 3.5 | 371 | 0.013 | 2.6 | 0.34 |
| 3A | 0.36 | 0.025 | 5.7 | 710 | 0.014 | 4.3 | 0.45 |
| 4 | 0.12 | 0.028 | 0.21 | 259 | 0.017 | 1.4 | 1.6 |
| 4A | 0.18 | 0.063 | 4.3 | 430 | 0.012 | 7.4 | 0.34 |
| 5 | 0.27 | 0.032 | 2.6 | 850 | 0.010 | 2.6 | 0.41 |
| 5A | 0.29 | 0.050 | 4.8 | 640 | 0.025 | 3.8 | 0.025 |
| 6 | 0.25 | 0.040 | 1.5 | 542 | 0.016 | 3.4 | 0.25 |
| 6A | 0.19 | 0.027 | 2.5 | 510 | 0.017 | 3.4 | 0.39 |
| 7 | ND | ND | ND | ND | ND | ND | ND |
| 7A | ND | ND | ND | 1.6 | ND | ND | ND |
| 8 | 0.11 | 0.028 | 0.39 | 270 | 0.014 | 0.73 | 0.45 |
| 8A | 0.12 | 0.020 | 0.86 | 350 | 0.012 | 1.6 | 0.58 |
Two separate samples of each product were analyzed for levels of the metals as described in the Methods section. Numerical values indicate µg of metal per g of raw product. ND indicates that the level of metal in the sample was below the level of detection. Note that the values for the replicate samples are generally in excellent agreement with each other. All of the samples except #7 which was a concentrated kratom extract contained measurable levels of metals. As would be expected for leaf-based products, levels of iron were consistently high. Of the toxic metals that were evaluated, the highest levels were for Pb, Ni and Cr.