Table 1.
Known and predicted physiochemical characteristics of known and emerging replacement perfluoroalkyl substances compared to legacy substances perfluorooctane sulphonic acid (PFOS) and perfluorooctanoic acid (PFOA).
| Compound | HFPO-DA | 6:2 Cl-PFAES | PFECHS | PFOS | PFOA |
|---|---|---|---|---|---|
| Cas # | 13252-13-6 | 756426-58-1 | 646-83-3 | 1763-23-1 | 335-67-1 |
| Structure |  |
 |
 |
 |
 |
| Molecular mass (g/mol) | 330.04 | 300.10 | 461.13 | 500.13 | 414.07 |
| Boiling point (˚C) | 129 | 211 | 221 | 249 | 189 |
| Melting point (˚C) | <40 | N/A | 74.1 | 71 | 55 |
| Partitioning coefficient (Log K) | 2.84 | 1.82a–3.81 | 3.19–5.92a | 4.9 | 4.81a–6.3 |
| Vapor pressure (mmHg) | 2.7 | 0.0268 | 9.38e-5 to 0.0159a | 0.0149 | 0.53 |
| Water solubility (mol/L) | >2.61 | 1.15e-3 | 9.68e-6 to 1.35e-3a | 1.07e-3 | 7.97e-3 |
| References | (PubChem 114481); [33] | (PubChem 22568738) | (PubChem 101650) | (PubChem 74483) | (PubChem 9554) |
a
Predicted.