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Link to relevant study record(s)

Reference
Endpoint:
basic toxicokinetics in vivo
Type of information:
(Q)SAR
Adequacy of study:
key study
Study period:
2001
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: publication, read-across
Justification for type of information:
On the basis of all evaluated data, the similarity of all category members of the ISOCARB is justified on basis of the physico-chemical properties, toxicological and ecotoxicological profiles. There is convincing evidence that these chemicals possess an overall common category profile. ISOCARB are aliphatic branched carboxylic acids and include substances with carbon chain lengths of C11 to C24. Their only functional group is the carboxyl group, which they share in common. All ISOCARB have a single branching at the C2 position, where the branches differ in chain length from methyl to decyl.
Objective of study:
toxicokinetics
Qualifier:
no guideline available
GLP compliance:
not specified
Species:
human
Route of administration:
oral: feed
Vehicle:
other: low-fat, natural foods
Details on exposure:
In a randomised, crossover, metabolic-ward study, 7 mildly hypercholesterolemic men were fed 3 natural food diets supplemented with behenate oil, palm oil, or high oleic acid sunflower oil. Mean serum lipid and lipoprotein concentrations and plasma triacylglycerol fatty acid comosition were determined druing final 4 d of each 3 week diet period.
Duration and frequency of treatment / exposure:
3 weeks
Remarks:
Doses / Concentrations:
39.5 % (by weight)
No. of animals per sex per dose:
7 men
Control animals:
no
Statistics:
The mean values obtained for the 3 dietary periods were compared by performing a repeated-measures analysis of variance (ANOVA). When the ANOVA showed the results of diets to be different, paired t tests wtih Bonferroni correction for multiple comparisons were peformed. After Bonferroni correction, statistical significance was set at a P value of 0.0167 (<0.05/3).
Details on absorption:
Only approximately 30% of the dietary behenic acid was absorbed.
Details on distribution in tissues:
The appearance of behenic acid in plasma triacylglycerol fatty acids as a rough measure of absorption suggests that little if any behenic acid was absorbed and distributed intact to the fatty acid pool.
Details on excretion:
Behenic acid was recovered in the feaces

Metabolites identified:
yes
Details on metabolites:
Behenic acid may be hydrolyzed shortly after absorption into shorter-chain saturated fatty acids.
Conclusions:
Interpretation of results (migrated information): low bioaccumulation potential based on study results
Executive summary:

Absorption: Only approximately 30% of the dietary behenic acid was absorbed.

Distribution: The appearance of behenic acid in plasma triacylglycerol fatty acids as a rough measure of absorption suggests that little if any behenic acid was absorbed and distributed intact to the fatty acid pool.

Metabolism: Behenic acid may be hydrolyzed shortly after absorption into shorter-chain saturated fatty acids.

Excretion: Behenic acid was recovered in the faeces.

Description of key information

Only approximately 30 % of the dietary Source substance 2  was absorbed. 

Key value for chemical safety assessment

Bioaccumulation potential:
no bioaccumulation potential
Absorption rate - oral (%):
30

Additional information

No data on the test substance are available. The results from a study of the appearance of behenic acid in lymph samples from rats suggest that only 11 -24 % of dietary behenic acid is absorbed. The results from a study of the fecal content of behenic acid in hamsters suggests that only 19 -29 % of behenic acid is absorbed. In humans, who are known to have a greater capacity for absorbing stearic aicd than do animals, fecal recovery of behenic acid suggests that the mean absorption of behenic aicd is about 30 %. The finding that behenate oil feeding resulted in high concentrations of plasma triacylglycerol myristic, palmitic, and stearic acids suggests that behenic acid may be hydrolysed shortly after absorption into shorter-chain saturated fatty acids. These findings suggest that dietary behenic acid is extensively degraded to cholesterol-raising saturated fatty acids (Cater, N. B., Denke, M. A., Behenic acid is a cholesterol-raising saturated fatty acid in humans, Am J. Clin. Nutr., 2001; 73, p41 -44).