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

Abstract

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 (K OW) 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 trans isomer, consistent with its lower K OW. 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.

Evaluation of 4-methylcyclohexanemethanol (MCHM) in a combined irritancy and Local Lymph Node Assay (LLNA) in mice

“…However, the abundances of the cis and trans isomers were approximately 33% and 57%, respectively, which are opposite to the relative abundances observed in MCHM. Similar differences in isomer ratios for MCHM and crude MCHM have been reported previously (Foreman et al, 2015; Dietrich et al, 2015). Thus, it is possible that the MCHM trans isomer drives the sensitization potential of crude MCHM.…”

Case study: the crude MCHM chemical spill investigation and recovery in West Virginia USA

“…28,30 Follow-up work by others weeks after the spill revealed that publicly accessible EPA databases such as SPARC and EPIWEB either contained or could be used to estimate these properties. 19,42 Based on these databases many of the tank liquid ingredients were moderately to highly soluble in water (up to 28 000 ppm for some ingredients at 21°C), volatile (up to 118 mmHg at 21°C), and their fate was temperature dependent. Others confirmed through experiments months after the spill that 4-MCHM volatilized from wa-ter, 14,15 and the water solubility and log K ow for each 4-MCHM isomer was found to be similar (1010 ppm and 2.46 and 1300 ppm and 2.35 at 21°C for transand cis-isomers, respectively).…”

“…The trans-isomer however was three times more volatile than the cis-isomer. 42,43 EPA databases could only estimate the properties of total 4-MCHM, not properties for each isomer.…”

Recent Development on the Electrochemical Detection of Selected Pesticides: A Focused Review

“…Applied fertilizers and pesticides can reach water sources either by surface run off or to groundwater by leaching through the soil. Heavy rain or extensive irrigation processes can further aggravate the leaching of contaminants to the groundwater [5]. Fertilizers and pesticides can cause serious health problems when constantly consumed by humans.…”