Coconut oil, reaction products with polyethylene glycol and trimethylolpropane

Endpoint summary

Additional information

Experimental data are not available for the assessment of the toxicokinetic properties of theCoconut oil, reaction products with polyethylene glycol and trimethylolpropane.

The substance is a derivative of a vegetable oil and clearly identified as UVCB substance. It is not practical to characterise many components a result of their complex structure and low concentration in the product. Coconut oil, reaction products with polyethylene glycol and trimethylolpropane contains > 50 substances at very low concentrations in the product. Therefore it would not be possible to perform toxikokinetic studies and to determine metabolites.

Read-across for toxicokinetic property assessment for some of the substances in the UVCB is a possible approach to characterise some apects of the toxicokinetic for the substance. Based on structurally similarity to mono-, di, and triglycerides a similar toxicokinetic behaviour can be expected. Triglycerides in general are important constituents of the daily food and substantially contribute to the energy supply of the organism. The mean daily dietary intake of triglycerides is 100 g. The major fatty acids part of these triglycerides exhibit chain lenghts of C8 to C18 (like in coconut oil). Triglyceride digestion begins in the intestinal tract. Initially, the triglyceride is hydrolyzed to alpha, ß- diglyceride, which is then hydrolyzed to ß-monoglyceride. These hydrolytic reactions occur at an oil-water interface. Approximately 28 % of the ß-monoglyceride is isomerized to alpha-monoglyceride, and approximately 75 % of the alpha-monoglyceride is further hydrolyzed to free glycerol. Free glycerol enters the intestinal wall independent of the lipids, and it has no further use in terms of lipid absorption. The free fatty acids and glycerol are available for the resynthesis of triglycerides. ß-Monoglycerides are not hydrolyzed because of their transfer to a water-soluble phase and, also, because of enzyme specificity.However, they can be acylated directly to triglyceride (International Journal of Toxicology (2004), 23 (Suppl. 2) 55 -94). The fatty acids serve as direct energy source in extrahepatic tissue (e. g. muscles). Glycerol is transported to the liver and subjected to hepatic metabolism (Forth, W., Henschler, D. und Rummel, W. (Ed.) (1987) Allgemeine und spezielle Pharmakologie und Toxikologie, 5. Auflage, BI-Wissenschaftsverlag; Karlson, P. (Ed.) (1984) Kurzes Lehrbuch der Biochemie, 12. Auflage, Georg Thieme Verlag, Stuttgart). PEGs were readily absorbed through damaged skin. Oral and intravenous studies on the PEGs indicated that these substances were excreted, unchanged, in the urine and feces. Ingested Coconut Oil was almost entirely absorbed with no mortality (Int J Toxicol Vol:18, Suppl 1 (1999) pp 43 -50). No data for the toxicokinetic of trimethylolpropane were found. Justification for read-across: In the dossier results of the structural similar substance coconut oil, reaction products of coconut fatty acid mono- or diglyceride with trimethylolpropaneethoxylate are used, however, mostly supportive. The substance is very similar to the test substance, the difference is mainly that in the test substance also the triglyceride is present.