Toxicity of Dietary Exposure to 3-Monochloropropanediol, Glycidol, and Their Fatty Acid Esters

3-Monochloropropane-1,2-diol (3-MCPD), 2,3-epoxy-1-propanol (glycidol), and their fatty acid esters are heat-induced food toxicants that have widely been investigated. This review study presents an overview of current knowledge about the dietary toxicity of 3-MCPD, glycidol, and their fatty acid esters. A literature search in two databases from January 2012 to December 2023 yielded 75 eligible articles for this review. The majority (73%) of the articles focused on 3-MCPD- and 3-MCPD fatty acid ester-induced toxicities. Nephrotoxicity (32%) was the most studied toxicity, whereas the least studied were carcinogenicity (4%) and hematotoxicity (4%). The metabolism of glycidol and its esters to 3-MCPD in the gastrointestinal tract remained a subject of contention as studies reported opposing findings. There was also new evidence of 3-MCPD-induced reproductive toxicity, hematotoxicity, and nephrotoxicity and 3-MCPD- and glycidol-induced neurotoxicity and genotoxicity. Findings suggest animal species-dependency in 3-MCPD’s carcinogenicity expression. Meanwhile, the 3-MCPD toxicity mechanism in obese rats is poorly understood. The review recommends further studies into the 3-MCPD toxicity mechanism in obese rats and the possible conversion of glycidol to 3-MCPD in gastrointestinal tracts.