D-Glucopyranose, oligomeric, butyl glycoside

Endpoint summary

Description of key information

Skin irritation (OECD 404): not irritating
Eye irritation (OECD 405): not irritating

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation / corrosion

Remarks:

other: in-vitro

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - Guideline study

Qualifier:

according to guideline

Guideline:

other: OECD Guidelines for Testing of Chemicals, Guideline No. 439: In Vitro Skin Irritation: Reconstructed Human Epidermis Test Method (adopted 22 July 2010)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: European Community (EC). Commission regulation (EC) No. 440/2008, Part B: Methods for the Determination of Toxicity and other health effects, Guideline B.46 “In Vitro Skin Irritation: Reconstructed Human Epidermis Model Test "

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EpiSkin™ SOP, Version 1.8 (February 2009), ECVAM Skin Irritation Validation Study: Validation of the EpiSkin™ test method 15 min - 42 hours for the prediction of acute skin irritation of chemicals

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Food and Consumer Product Safety Authority (VWA), GG Utrecht, The Netherlands

Species:

human

Strain:

other: EPISKIN Small ModelTM (EPISKIN-SMTM), reconstructed three-dimensional human epidermis model

Details on test animals or test system and environmental conditions:

TEST SKIN MODEL
- Source: SkinEthic Laboratories, Lyon, France

TEST METHOD
This model is a three-dimensional human epidermis model, which consists of adult human-derived epidermal keratinocytes which have been seeded on a dermal substitute consisting of a collagen type I matrix coated with type IV collagen. The keratinocytes were cultured for 13 days, which results in a highly differentiated and stratified epidermis model comprising the main basal, supra basal, spinous and granular layers and a functional stratum corneum. Irritant materials are identified by their ability to penetrate the stratum corneum and to damage the underlaying cell layers which is determined through a decrease in cell viability as determined by MTT reduction assay.

ADAPTATION TO CELL CULTURE CONDITIONS
On the day of receipt, the tissues were transferred to 12-well plates and preincubated with prewarmed Maintenance Medium (SkinEthic Laboratories, Lyon, France) for 24 h at 37 °C.

INCUBATION CONDITIONS (INCUBATOR)
- Temperature (°C): 36.2-37.6
- CO2 gas concentration (%): 5.0 ± 0.5
- Humidity (%): 80-97

Type of coverage:

other: open (in vitro system)

Preparation of test site:

other: intact reconstructed human epidermis

Vehicle:

unchanged (no vehicle)

Controls:

other: concurrent control tissues treated with PBS served as negative controls, positive controls were exposed to 5% SDS

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 11.9-13.6 mg on the skin tissue moistened with 5 μL of Milli-Q water (Millipore Corp., Bedford, Mass., USA)

POSITIVE CONTROL SUBSTANCE:
- Positive control substance: SDS (Sigma Aldrich, Zwijndrecht, The Netherlands), 5% (v/v) in PBS

Duration of treatment / exposure:

15 min

Observation period:

Not applicable. Post-treatment incubation period: 44 h

Number of animals:

Not applicable. The test was performed in triplicates for each treatment and control group.

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: the tissues were washed with PBS to remove residual test substance.
- Time after start of exposure: 15 min
- Post-treatment incubation period: 44 h

CELL VIABILITY MEASUREMENTS
For determining alterations in cell viability, MTT reduction assays were performed 44 h after the incubation period. Therefore, tissues were incubated in 2 mL prewarmed MTT solution (0.3 mg/mL) for approximately 3 h at 37 °C and 5% CO2. After aspiration of the MTT solution, tissues were placed on blotting paper for drying. Extraction of the formazan product was carried out in 0.5 mL isopropanol (Merck, Darmstadt, Germany). The optical density was measured at 570 nm wave length in a 96 wells plate using a plate spectrophotometer (TECAN Infinite® M200 Pro Plate Reader).

Irritation parameter:

other: cell viability (% of negative control)

Basis:

other: mean value of negative controls (sterile Milli-Q water)

Time point:

other: 15 min

Score:

100

Reversibility:

other: reversibility: not applicable

Irritation parameter:

other: cell viability (% of negative control)

Basis:

other: mean value of positive controls (5% SDS)

Time point:

other: 15 min

Score:

5

Reversibility:

other: reversibility: not applicable

Irritation parameter:

other: cell viability (% of negative control)

Basis:

other: mean value of the test item (100%)

Time point:

other: 15 min

Score:

99

Reversibility:

other: reversibility: not applicable

Other effects:

No further effects were observed.

Table 3. Results of MTT assay after 15 min exposure

	Negative control			Positive control			Test item
Tissue sample	1	2	3	1	2	3	1	2	3
OD570	0.908 0.947	0.941 0.968	0.970 1.001	0.045 0.051	0.039 0.065	0.042 0.057	0.957 0.982	0.951 0.845	0.988 0.979
OD570 (mean)	0.928	0.955	0.986	0.048	0.052	0.050	0.970	0.898	0.984
SD	0.028	0.019	0.022	0.004	0.018	0.011	0.018	0.075	0.006
OD550 (mean values of replicates ± SD)	0.956 ± 0.029			0.050 ± 0.002			0.950 ± 0.046
Viability (%)	100			5			99

OD = optical density; SD = standard deviation

In this table, the values are corrected for background absorption (0.042). Isopropanol was used to measure the background absorption.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: JMAFF guidelines (2000)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Food and Consumer Product Safety Authority (VWA), GG Utrecht, The Netherlands

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Charles River France, L’Arbresle Cedex, France
- Age at study initiation: at least 6 weeks
- Weight at study initiation: at least 1.0 kg
- Housing: animals were individually housed in labelled cages with perforated floors (Ebeco, Germany, dimensions 67 x 62 x 55 cm) and shelters (Ebeco, Germany, dimensions 40 x 32 x 23 cm).
- Diet: pelleted diet for rabbits (Global Diet 2030 from Harlan Teklad®, Mucedola, Milanese, Italy) approximately 100 g per day. Hay (TecniLab-BMI BV, Someren, The Netherlands) and wooden sticks (Swedish aspen wood, Bioservices, Uden, The Netherlands) were available during the study period.
- Water: tap water, ad libitum
- Acclimation period: at least 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-24
- Humidity (%): 40-70%
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12/12

Vehicle:

unchanged (no vehicle)

Controls:

other: the untreated eye served as control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 100 mg (99.6-100.5 mg), moistened with 0.1 mL Elix water

Duration of treatment / exposure:

single application without washing

Observation period (in vivo):

72 h
reading time points: 1, 24, 48 and 72 h

Number of animals or in vitro replicates:

3 males

Details on study design:

SCORING SYSTEM: Draize scoring system

TOOL USED TO ASSESS SCORE: 2% fluorescein

Irritation parameter:

cornea opacity score

Basis:

animal #1

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #2

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #3

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #1

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #2

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #3

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #1

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #2

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #3

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #1

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0

Max. score:

0

Reversibility:

other: reversibility: not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #2

Remarks:

Mean value eye irritation scores

Time point:

24/48/72 h

Score:

ca. 0.3

Max. score:

1

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

ca. 0.3

Max. score:

1

Reversibility:

fully reversible

Irritant / corrosive response data:

Instillation of the test substance into one eye of each of three rabbits resulted in irritation of the conjunctivae, which consisted of redness, chemosis and/or discharge. Conjunctival irritation had completely resolved within 24 h in one animal and within 48 h in the other two animals. No iridial irritation and corneal opacity were observed. Treatment of the eyes with 2% fluorescein 24 h after test substance instillation revealed no corneal epithelial damage.

Other effects:

No further local or systemic effects were observed.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

CLP: not classified
DSD: not classified

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation

An in vitro skin irritation study according to OECD guideline 439 is available for D-Glucopyranose, oligomeric, butyl glycoside. In this study, a reconstructed three-dimensional human epidermis model was used to investigate the effects of the undiluted test substance on the viability of epidermal keratinocytes (NOTOX B.V., 2012). After 15-min exposure the test substance, the viability of human keratinocytes was 99% compared to the negative control (100%). Since the mean relative tissue viability was ≥ 50% after 15 minutes treatment, the test substance was considered to be non-irritant to human skin according to the criteria laid down in OECD guideline 439.

Eye irritation

One study investigating the eye irritation of D-Glucopyranose, oligomeric, butyl glycoside is available (NOTOX B.V., 2012). In this study, the unchanged test material was placed into one respective eye of 3 male rabbits. The other eye remained untreated and served as control. The eyes were examined and scored 1, 24, 48 and 72 h after application. Instillation of the test substance into the eyes of the animals resulted in irritation of the conjunctivae, which consisted of redness, chemosis and/or discharge. However, these effects were fully reversible within 24 h in one animal and within 48 h in the other two animals, respectively. No iridial irritation and corneal opacity were observed and treatment of the eyes with 2% fluorescein 24 h after test substance instillation revealed no corneal epithelial damage. The mean cornea, iris and chemosis scores after 24, 48, and 72 h were 0 for all 3 animals. For conjunctivae, mean scores after 24, 48, and 72 h were 0/0.3/0.3 for the 3 animals. Based on these results, the test substance is not considered to be an eye irritant.

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:
There is only one study available.

Justification for selection of eye irritation endpoint:
There is only one study available.

Justification for classification or non-classification

The available data on skin and eye irritation of D-Glucopyranose, oligomeric, butyl glycoside do not meet the criteria for classification according to Regulation (EC) No 1272/2008 or Directive 67/548/EEC, and are therefore conclusive but not sufficient for classification.