Isostearic acid, esters with methyl α-D-glucoside

Endpoint summary

Description of key information

Oral
female rat LD50 > 2000 mg/kg bw (no mortalities)
Acute Toxic Class Method; OECD TG 423
male/female rats LD50 > 2000 mg/kg bw 
Acute Oral Toxicity, OECD TG 401
Read Across: Stearic acid, esters with methyl α-D-glucoside
Dermal
male/female rats LD50 > 2000 mg/kg bw
Acute Dermal Toxicity, OECD TG 402 
(one mortality, 10 animals tested), occlusive dressing, 24 hrs exposure
Inhalation
Waiving: no tests performed due to low  volatility of test substance and improbability of the generation of fine dusts or aerosols at the working place.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

2 000 mg/kg bw

Additional information

Oral

In an acute oral toxicity study according to OECD TG 423, groups of fasted, young adult female Wistar rats were given a single oral dose of test substance Isostearic acid, esters with methyl α-D-glucoside (100% UVCB substance, typically consisting of 80% Methyl Glucoside Isostearate Esters (mainly Di-), 16% Isostearic Acid, 4% Methyl Glucoside) in 1% aq. carboxymethyl cellulose and water. Isostearic acid, esters with methyl α-D-glucoside was administered by oral gavage at 300 mg/kg bw. In a stepwise procedure additional groups of females were dosed at 300 and 2000 mg/kg body weight. All animals were subjected to daily observations and weekly determination of body weight. Macroscopic examination was performed after terminal sacrifice on day 15.

Oral LD₅₀Females > 2000 mg/kg bw

No mortality occurred. Hunched posture and/or piloerection were noted in all animals on day 1 and in the first set of animals at 300 mg/kg bw on day 2. The body weight gain of the animals over the study period was considered to be normal. No abnormalities were found at macroscopic post mortem examination of the animals.

In this study test substance Isostearic acid, esters with methyl α-D-glucoside is practically non-toxic based on LD₅₀in female rats.

In an acute oral toxicity study (limit test, according to OECD 401,1987), 5 male and 5 female Wistar rats were given a single oral dose of Stearic acid, esters with methyl α-D-glucoside (100 % a.i.) at a concentration of 2000 mg/kg bw and observed for 14 days. The test substance was administered as a 20 % dispersion in water.

Oral LD₅₀Males and Females > 2000 mg/kg bw.

No animal died. No clinical signs or effects on body weight were observed. Gross pathological examinations at 14 days p.a. (terminal necropsy) revealed a marbled lung of one male rat. The kidney of one male was deformed with a red spot on the surface; two males had a marbled kidney. A hydrometra was found in the uterus of two females. The findings were not test item dependent.

Stearic acid, esters with methyl α-D-glucoside (100 % a.i.) is practically non toxic at an oral dose of 2000 mg/kg bw.

 

Rationale for Read-Across:

Based on the structural analogue approach to Isostearic acid, esters with methyl α-D-glucoside read across from Stearic acid, esters with methyl α-D-glucoside is considered acceptable.

The structural analogue approach is scientifically justified by close similarities with regard to physico-chemical properties and structural aspects.

Stearic acid, esters with methyl α-D-glucoside is a reaction product of methyl glucoside with stearic acid, a linear saturated C18 fatty acid.

Isostearic acid, esters with methyl α-D-glucoside is a reaction product of methyl glucoside with the branched isostearic acid (100% UVCB substance).

Due to its esterification with the branched isostearic acid, isostearate is more hydrophobic than the sesquistearate.

For Isostearic acid, esters with methyl α-D-glucoside and for Stearic acid, esters with methyl α-D-glucoside the reaction leads to a fatty acid ester in which the four OH-groups of glucose are partially esterfied.

In the case of isostearic acid, esters with methyl α-D-glucoside the product is composed of methylglucoside (4 %), methyl glucoside ester (approx. 83 % mono-, di-, and triester (mainly diester)) and of approx. 13 % free fatty acids. More than 90% of the fatty acids have a carbon number of 18, with some chain length distribution between C16 and C20. The main components are mono- and poly branched C18 fatty acids, in which the branching occurs mainly medium-chained, mostly methylenic, which accounts for its good biodegradability. However, a precise structure of isostearic acid does not exist.

 Dermal

In an acute dermal toxicity study according OECD guideline 402, 5 male and 5 female young adult Wistar rats were dermally exposed to isostearic acid, esters with methyl α-D-glucoside (100% UVCB substance, test substance was dosed undiluted) for 24 hours to 10% of body surface area at doses of 2000 mg/kg bw. Animals were observed for 15 days.

Dermal LD₅₀Males and Females > 2000 mg/kg bw (limit test)

There were no treatment related clinical signs, necropsy findings or changes in body weight. The death of one male on day 2 at 2000 mg/kg bw was considered related to treatment rather than related to the test substance.

The test substance isostearic acid, esters with methyl α-D-glucoside is practically non-toxic.

Inhalation

Testing by the inhalation route is not appropriate because exposure of humans via inhalation is unlikely due to the very low vapour pressure of the test substance, its high boiling point and the low likelihood of the generation of aerosols or fine dusts at the working place.

Justification for classification or non-classification

Based on the results for the test substance and read-across from two studies with chemically closely related substance there is no need for classification of Isostearic acid, esters with methyl α-D-glucoside according to Directive 67/548/EEC as well as GHS Regulation EC No 1272/2008 with respect to oral toxicity. No labelling is required.

Further, the test substance Isostearic acid, esters with methyl α-D-glucoside has not to be classified and labelled according to Directive 67/548/EEC as well as GHS Regulation EC No 1272/2008 with respect to dermal toxicity.