Background: Fatty acid ethyl esters (FAEEs) are nonoxidative metabolites of ethanol. FAEEs are found in liver, pancreas, and adipose tissues up to 24 h after consumption of ethanol, and on that basis, they are potentially useful markers for ethanol intake. In this study with rats, we investigated the efficacy of using FAEEs in liver and in adipose tissue as postmortem markers for premortem ethanol ingestion.
Methods: An animal study was conducted in which test rats received injections of ethanol and control rats received injections of normal saline. The rats were killed 2 h after the injections. The bodies of the animals were stored at 4 degrees C up to 12 h, and samples of liver and adipose tissues were collected at different time intervals and processed for FAEE quantification. In another set of experiments, the rats received injections and were killed as described above, but bodies of animals from both groups were stored at 4, 25, or 37 degrees C for up to 72 h, and liver samples were collected and processed for FAEE quantification.
Results: FAEEs were detected up to 12 h after death in liver and adipose tissue samples from the bodies of ethanol-treated animals stored at 4 degrees C; negligible amounts were detected in the bodies of animals that received normal saline. Adipose tissues contained higher amounts of FAEEs than liver, as well as more species: eight FAEE species in adipose tissue and five in liver tissue. Higher concentrations of FAEEs were detected in livers of treated animals stored at 25 degrees C for up to 48 h than in livers of controls stored under the same conditions.
Conclusions: For at least 12 h after death, FAEEs in liver and adipose tissues are useful postmortem markers of premortem ethanol ingestion.