D-Glucopyranose, oligomers, branched and linear C9-11-alkyl glycosides

Endpoint summary

Description of key information

Skin irritation (OECD 404): not irritating (≤ 50% AS), irritating (> 50% AS)
Eye irritation (OECD 405): not irritating (1%), irritating (1% < c ≤ 10% AS), corrosive (> 10% AS)
Existing data indicate that the skin irritation potential increases with increasing chain length, whereas for eye irritation the whole category has to be classified with R41.

Key value for chemical safety assessment

Skin irritation / corrosion

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation

Two non-GLP studies investigating the skin irritating potential of D-Glucopyranose, oligomers, branched and linear C9-11-alkyl glycosides (CAS 157707-87-4) are available, which were performed equivalent or similar to OECD guideline 404. In the key study, six animals per dose were exposed to the test substance undiluted (50% AS) or at concentrations of 30% (w/v) (15% AS) and 3% (w/v) (1.5% AS) in phosphate buffered saline (1/15 M pH 7.2), respectively. The mean erythema score over 24, 48 and 72 h and all animals was 0.7 for the undiluted test substance, and effects were not fully reversible within 48 h. However, this observation period was insufficient to assess the full reversibility of skin irritation. No erythema was noted after exposure to the test substance at 3 and 30% and no edema was seen at any concentration tested (Drug Safety Testing Center, 1988). In a further study in rabbits, the test substance at 48-52% AS induced erythema in all three animals with a mean erythema score of 1 of all animals over 24, 48 and 72 h. In 2 of 3 tested animals, an edema score of 2 was determined (Zeneca, 1993). However, this study was performed under occlusive conditions and the observation period was insufficient to assess the reversibility of effects on the skin.

There are also studies available from structurally related substances, which are member of the category. Undiluted Decyl glucoside, an alkyl polyglycoside with a main chain length of C10, did not reveal any effects on the rabbit skin after an observation period up to 8 days (BASF, 1982), thus supporting the non-irritating potential of D-Glucopyranose, oligomers, branched and linear C9-11-alkyl glycosides.

Based on these results, the test substance may be classified as not irritating, if the active substance content does not exceed 50% AS. Since no information is available for the neat substance, the test substance at > 50% has to be classified as skin irritating.

Eye irritation

Several studies on the eye irritation potential of D-Glucopyranose, oligomers, branched and linear C9-11-alkyl glycosides are available. These studies were performed equivalent or similar to OECD guideline 405 with active substance contents ranging from 1 to 50%.

In a key study, the undiluted test substance (50% AS) was placed into one of the respective eyes of 6 rabbits (Drug Safety Testing Center, 1988). The eyes were examined and scored 1, 3, 6, 24, 48, 72 h and 4, 7, 14 and 21 d after treatment. Instillation of the undiluted test substance induced corneal and conjunctival, but no iridial effects on the rabbit eye. The mean cornea, iris, conjunctivae and chemosis scores over 24, 48, and 72 h were 1.2/0/1.2/1.2 for all 6 animals. The effects on conjunctivae were fully reversible within 14 days. In contrast, effects on cornea were not reversible within the 21-day observation period. Eye irritation was also observed in a study with a single animal receiving the test substance at 48-52% AS. The mean cornea, iris, conjunctivae and chemosis scores over 24, 48, and 72 h were 1.7/0.7/1.2/1.2 for this animal. Reversibility of the effects was not stated (Zeneca, 1993). Based on these results,the test substance causes severe damage to the eye at active substance contents ≥ 50%.

Another eye irritation study was conducted with 20, 10 and 2% AS, corresponding to test material concentrations of 49.75, 24.88 and 4.98% in distilled water, respectively (Drug Safety Testing Center, 1993). At 20% AS, the test substance induced irreversible effects on cornea in 2 of 3 rabbits up to the end of the 21-day observation period, which is consistent with the persistent effects observed at 50% AS in the study mentioned above. In contrast, the test substance at 10% AS induced mean conjunctivae scores of 2 over 24, 48, and 72 h in all 3 animals and effects on conjunctivae were fully reversible within 14 days. Based on these results, the test substance at 20% AS causes severe damage to the eyes, whereas the test substance at 10% AS is irritating to the eye.

The eye irritating potential of the test substance at 10% AS was further confirmed in a study showing a mean conjunctivae score of 2.45 over 24, 48, and 72 h in 6 rabbits. Effects on the conjunctivae were fully reversible after a period of 14 days. In contrast, the test substance at 1% AS only induced mild conjunctival effects, which were fully reversible within 7 days after exposure, and thus does not require a classification (Drug Safety Testing Center, 1990).

Respiratory tract

This information is not available and not mandatory according to Regulation (EC) No 1907/2006.

Justification for selection of skin irritation / corrosion endpoint:
The selected study is the most adequate and reliable study based on overall quality assessment (refer to the endpoint discussion for further details).

Justification for selection of eye irritation endpoint:
No study was selected, since all available studies showed positive results for eye irritation, and thus contribute to classification based on specific concentration limits.

Effects on eye irritation: corrosive

Justification for classification or non-classification

According to the criteria of Regulation (EC) No 1272/2008, the substance has to be classified as Eye Irrit. 2 (H319) at concentrations > 1% and ≤ 10% a.i.. At concentrations > 10% a.i., the substance meets the criteria for classification as Eye Dam. 1 (H318) according to Regulation (EC) No 1272/2008 and as Xi (R41) according to Directive 67/548/EEC. Furthermore, the test substance at concentrations > 50% has to be classified as Skin Irrit. 2 (H315) according to Regulation (EC) No 1272/2008 and as Xi (R38) according to Directive 67/548/EEC.