90-day dietary toxicity study with esterified propoxylated glycerol (EPG) in micropigs.

The subchronic (90-day) toxicity of esterified propoxylated glycerol (EPG) was assessed in micropigs. Animals (5/sex/group) received feed containing 5%, 10%, and 17% EPG, mixed accordingly throughout the study to deliver 1.5, 3, and 5 g/kg bw/day of EPG, respectively. Corn oil served as the vehicle control (0 g/kg bw/day). Subsets of animals were evaluated at Week 6; the remainder between Weeks 12 and 14. With the exception of liver and serum vitamin levels, statistically significant difference between control and EPG groups were seen sporadically, and with no apparent connection to treatment and/or no consistency across time intervals. EPG intakes of 3 and 5 g/kg bw/day, but not at 1.5 g/kg bw/day were associated with significantly lower serum 25-OH vitamin D levels. Serum total vitamin D levels were significantly lower across all EPG groups. There were also trends toward lower levels of liver vitamins A and E among EPG-treated animals, but the effects were less consistent. The effects on vitamin levels observed in EPG-treated animals were not accompanied by any signs of vitamin deficiency (e.g., effects on growth, clinical signs, or clinical pathology), and might have been related to the larger mass of EPG acting as a lipid "sink" during transit in the gastrointestinal tract.