Partitioning, Aqueous Solubility, and Dipole Moment Data for cis - and trans -(4-Methylcyclohexyl)methanol, Principal Contaminants of the West Virginia Chemical Spill

In 2014, the U.S. National Response Center recorded more than 30000 incidents of oil spills, chemical releases, or maritime security issues, including crude (4-methylcyclohexyl)methanol (MCHM) that contaminated river and drinking water in West Virginia. This research yielded physicochemical partitioning data for the two major compounds released in West Virginia, cis- and trans-(4-methylcyclohexyl)methanol. Octanol?water partition coefficients (KOW) were 225 for cis-4-MCHM and 291 for trans-4-MCHM. The aqueous solubility for total 4-MCHM was 2250 mg/L at 23 ?C; solubilities of individual isomers were dependent on their mole fractions. The cis isomer was more soluble and less well sorbed to activated carbon than the transisomer, consistent with its lower KOW. The partition behavior is supported by a larger computed solvated dipole moment for the cis form than for the trans form at the MP2 aug-cc-pwCVDZ SMD level of theory. Different partition properties would result in the differential fate and transport of cis- and trans-4-MCHM in aqueous environments.