Hepatic fatty acid conjugation of 2‐chloroethanol and 2‐bromoethanol in rats

To study the formation of fatty acid conjugates of 2‐chloroethanol (2‐CE) and 2‐bromoethanol (2‐BE), rats were administered (by gavage) 50 mg/kg of 2‐CE and 2‐BE in mineral oil and sacrificed on fifth day of the treatment. Hepatic microsomal lipids were extracted, and the fatty acid esters were separated by preparative thin‐layer chromotography. The ester fraction was further purified by reverse‐phase, high‐performance liquid chromatography and analyzed by ammonia chemical ionization mass spectrometry. Pseudomolecular ions (M + N⁺H₄, base peak) at m/z 336/338, 362/364, and 364/366 in a ratio of 3:1 and 380/382 and 408/410 in a ratio of 1:1 confirmed the in vivo formation of 2‐chloroethyl palmitate, 2‐chloroethyl oleate, 2‐chloroethyl stearate, 2‐bromoethyl palmitate, and 2‐bromoethyl stearate, respectively. These results demonstrate the formation of fatty acid conjugates of 2‐CE and 2‐BE in vivo. These fatty acid conjugates may be retained in the body for a longer time and cause toxic manifestations.