TABLE 1.
IC20, IC50, and IC80 of arsenical compounds against the acetoclastic methanogenic activity of Eerbeek sludge with acetate as the substrate
| Compound (alternate substrate) | Mol wt | IC20 (μM) | IC50 (μM) | IC80 (μM) |
|---|---|---|---|---|
| Inorganic species | ||||
| As(III) | 122.9 | 9.1 | 15.5 | 23.5 |
| As(III) (H2a) | 122.9 | 10.2 | 27.1 | 79.2 |
| Arsenite (lactatea) | 122.9 | 3.4 | 4.4 | 6.1 |
| As(V) | 138.9 | >500 | >500 | >500 |
| As(V) (H2a) | 138.9 | >500 | >500 | >500 |
| Methylated organoarsenic compounds | ||||
| MMA(V) | 140.0 | >5,000 | >5,000 | >5,000 |
| DMA(V) | 138.0 | >5,000 | >5,000 | >5,000 |
| MMA(III) | 123.9 | 2.2 | 9.1 | 17.9 |
| Phenylarsonic compounds | ||||
| p-Arsanilic acid | 217.1 | >2,300 | >2,300 | >2,300 |
| Roxarsone | 263.0 | 251 | 425 | 780 |
| 4-Hydroxy-3-arsanilic acid | 233.1 | >600 | >600 | >600 |
a
H2 or lactate (as indicated) instead of acetate was the substrate supplied in this assay.