α,α,α',α'-tetramethylxylene-α,α-diol

Endpoint summary

Description of key information

For this endpoint, there is no data on the isomer mixture.

Skin irritation

The acute dermal irritation of the meta isomer was evaluated in rabbits according to OECD 404 guideline (Wang, 2012b). Four healthy Japanese white rabbits were taken for the test. 0.5 g test substance was applied to an area of shaved skin on left of back of four healthy rabbits and the application site was covered with a semi-occlusive dressing for four hours. Following exposure, dermal irritation was evaluated by at 24, 48 and 72h after removal of the dressing. No erythema was observed on the treated skin area of any rabbit. There was no erythema on the control area of the rabbits. The average score of skin responses was 0. In conclusion, under the experimental conditions of the test, a,a,a’,a’-tetramethyl-m-xylene-a,a’-diol is considered as non-irritant when applied topically to rabbit skin.

The skin irritation potential of the meta and para isomers was evaluated in chemico using Toxtree. Both isomers were considered to be not Irritating or Corrosive to skin.

In conclusion, m/p-DIOLS can be considered as not skin irritant.

Eye irritation

The potential of meta isomer to induce ocular irritation was evaluated in rabbits according to OECD 405 guideline (Wang, 2012c). Four healthy Japanese white rabbits were taken for the test. 0.1 g of the test substance was put into the left eye of four healthy rabbits. The right eye was treated with 0.1 ml normal saline and served as control. The left eye was not treated and served as control. The eyes were not rinsed after administration of the test item. Ocular reactions were observed approximately 1 hour, 24, 48 and 72 hours after the administration. No eye reactions occurred after exposure until the 72 h. Therefore the rabbits were not observed anymore. In conclusion, under these experimental conditions, a,a,a’,a’-tetramethyl-m-xylene-a,a’-diol was not irritant when administered by ocular route to rabbits.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

21 June 2011 - 24 June 2011

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study has some deviations and some information in the report is incomplete. However the study was conducted in accordance with current guidelines and the report includes a QA certification statement.

Qualifier:

according to guideline

Guideline:

other: The Guidelines for the Testing of Chemicals (State Environmental Protection Administration of China, 2004.5, 404, Acute Dermal Irritation Test)

Deviations:

no

GLP compliance:

no

Remarks:

The laboratory has no GLP accreditation (nevertheless the project plan and the report were audited by the Quality Assurance Unit)

Species:

rabbit

Strain:

other: Japanese white

Details on test animals or test system and environmental conditions:

Four healthy male albino rabbits, 2.1-2.2kg, were supplied by Beijing KeYu Expenerimental Animals Products Center (Certificate No:
SCXK(Jing)2007 -0003).

Animals were kept in animal room in Institute of Laboratory Animal Sciences, CAMS (normal environment, Certificate No.: SYXK(Jing)
2010-0030). Environmental conditions for animal husbandry are maintained with the 12-h light/dark cycle, the temperature of 20-23°C,
and the relative humidity of 40-70%. All animals had free access to sterilized drinking water and irradiation sterilized commercial pellet diets
except during exposure (Beijing HFK Bio-technology Co., Ltd. Certificate No.: SCXK(Jing) 2009- 0008). The tap water was of drinking
water quality (Sterile water for reverse osmosis).Animals were acclimatized to the laboratory conditions for at least 5d prior to the test.

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

water

Controls:

other: The right flank was treated with 0.5 ml distilled water as control

Amount / concentration applied:

0.5 grams

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

4

Details on study design:

24 hours before the test, the fur on the bilateral dorsal sides (3 X 3 cm2) of rabbits was removed by clipping, respectively.
It was treated with 0.5 g substance (moistened with distilled water) on the left skin area evenly at the second day, and covered with one layer of sulfate paper and two layers of surgical bandages, and fixed with non-irritation tapes, The right free fur area was treated with 0.5 ml distilled water as control, the covering was same as the left, The exposure duration was 4 hours.
Afterwards, the dressing was removed and the residual test substance was cleaned with detergent and warm water.
The test areas were evaluated for both erythema and edema, and compared with the control areas, Scores were given at 24, 48 and 72h
following removal of the dressing. The irritation intensity of the test substance was recorded according to the criteria in "The Guidelines for the Testing of Chemicals".

Irritation parameter:

erythema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

edema score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

No erythema was observed on the treated skin area of any rabbit. There was no erythema on the control area of the rabbits. The average score of skin responses was zero.

Interpretation of results:

GHS criteria not met

Conclusions:

Under the experimental conditions of the test, a,a,a',a'-tetramethyl-m-xylene-a,a'-diol is considered as non-irritant when applied topically to rabbit skin.

Executive summary:

The acute dermal irritation of the meta-diols isomer was evaluated in rabbits according to OECD 404 guideline.

Four healthy Japanese white rabbits were taken for the test. 0.5g test substance was applied to an area of shaved skin on left of back of four healthy rabbits and the application site was covered with a semi-occlusive dressing for four hours. Following exposure, dermal irritation was evaluated by at 24, 48 and 72h after removal of the dressing. No erythema was observed on the treated skin area of any rabbit. There was no erythema on the control area of the rabbits. The average score of skin responses was 0. In conclusion, under the experimental conditions of the test, a,a,a',a'-tetramethyl-m-xylene-a,a'-diol is considered as non-irritant when applied topically to rabbit skin.

Reference 2

Endpoint:

skin irritation / corrosion, other

Remarks:

in chemico

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
Toxtree (Estimation of Toxic Hazard - A Decision Tree Approach)

2. MODEL (incl. version number)
Version 2.6.13

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
1999-85-5: OC(c1cccc(C(O)(C)C)c1)(C)C
2948-46-1: C(C)(C)(O)c1ccc(C(C)(C)O)cc1

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
- Defined endpoint: Skin irritation
- Unambiguous algorithm: see attached rules
- Defined domain of applicability: rules were developed for Identifying Chemical Substances with no Skin Irritation or Corrosion Potential whatever the chemical structure
- Appropriate measures of goodness-of-fit and robustness and predictivity: not relevant
- Mechanistic interpretation: according to the rules and decision tree of the specific end-point

5. APPLICABILITY DOMAIN
- Descriptor domain: Defined by the rules
- Structural and mechanistic domains: Defined by the rules
- Similarity with analogues in the training set: not relevant

6. ADEQUACY OF THE RESULT
The estimation is coherent with the available in vivo data

Qualifier:

according to guideline

Guideline:

other: REACH guidance. Chapter R.6: QSARs and grouping of chemicals

Version / remarks:

May 2008

Principles of method if other than guideline:

Toxtree (Estimation of Toxic Hazard - A Decision Tree Approach) (Version 2.6.13)

Specific details on test material used for the study:

SMILES:
1999-85-5: OC(c1cccc(C(O)(C)C)c1)(C)C
2948-46-1: C(C)(C)(O)c1ccc(C(C)(C)O)cc1

Remarks on result:

other: Not Irritating or Corrosive to skin

Interpretation of results:

GHS criteria not met

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

Study period:

21 June 2011 - 24 June 2011

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study has some deviations and the information in the report is limited. However the study was conducted in accordance with current guidelines and the report includes a QA certification statement.

Qualifier:

according to guideline

Guideline:

other: “The Guidelines for the Testing of Chemicals (State Environmental Protection Administration of China, 2004.5, 405, Acute Eye Irritation Test)

Deviations:

no

GLP compliance:

no

Remarks:

The laboratory has no GLP accreditation (nevertheless the project plan and the report were audited by the Quality Assurance Unit)

Species:

rabbit

Strain:

other: Japanese white

Details on test animals or tissues and environmental conditions:

Four healthy male albino rabbits, 2.1-2.3kg, were supplied by Beijing KeYu Expenerimental Animals Products Center (Certificate No:
SCXK(Jing)2007 -0003).

Animals were kept in animal room in Institute of Laboratory Animal Sciences, CAMS (normal environment, Certificate No.: SYXK(Jing)
2010-0030), Environmental conditions for animal husbandry are maintained with the 12-h light/dark cycle, the temperature of 20-23 'C ,
and the relative humidity of 40-70%. All animals had free access to sterilized drinking water and irradiation sterilized commercial pellet diets
except during exposure (Beijing HFK Bio-technology Co., Ltd. Certificate No,: SCXK(Jing) 2009- 0008). The tap water was of drinking
water quality (Sterile water for reverse osmosis). Animals were acclimatized to the laboratory conditions for at least 5d prior to the test.

Vehicle:

unchanged (no vehicle)

Controls:

other: the right eye was used as the control and treated with 0.1 ml saline

Amount / concentration applied:

0.1 gram

Duration of treatment / exposure:

0.1 g was put in the left eye of the rabbits at the start of the study

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

4

Details on study design:

Animals were examined ophthalmoscopically and evaluated with sodium fluorescein prior to the exposure to assure that they were free of
ocular defects, lesions, or irritation that may have interfered with the goals ofthe test.
0.lg test substance was put into the conjunctival sac of the left eye of each test rabbit (4 rabbits). The eye-lids were then gently keep closed.
The eyes were not washed within 24 hours after exposure. The right eye treated with 0.1 ml normal saline and served as control.
The eye reactions, including those of cornea, iris, and conjunctiva, were evaluated at 1, 24, 48 and 72h after exposure, respectively. One drop
of 5% sodium fluorescein solution was instilled into both eyes of each rabbit for evaluation areas of the cornea opacity. At the same time, all
scorings were taken. The irritation intensity of test substance was recorded according to the criteria in "The Guidelines for the Testing of
Chemicals" .

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

3

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

0

Max. score:

4

Irritant / corrosive response data:

No eye reactions occurred after exposure until 72h. The Index of Acute Ocular Irritation (I.A.O.I.) was "0", which was classified to non-irritation.

Other effects:

At necropsy, no effects were observed.

Interpretation of results:

GHS criteria not met

Conclusions:

Not irritating to the eye

Executive summary:

The potential of a,a,a',a'-tetramethyl-m-xylene-a,a'-diol to induce ocular irritation was evaluated in rabbits according to OECD guideline.

Four healthy Japanese white rabbits were taken for the test. 0.1 g of the test substance was put into the left eye of four healthy rabbits. The right eye was treated with 0.1 ml normal saline and served as control.  The right/left eye was not treated and served as control. The eyes were not rinsed after administration of the test item. Ocular reactions were observed approximately 1 hour, 24, 48 and 72 hours after the administration.

No eye reactions occurred after exposure until the 72 h. Therefore the rabbits were not observed anymore.

In conclusion, under these experimental conditions, the test item is not irritant when administered by ocular route to rabbits.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

According to EU Regulation (EC) N0. 1272/2008 (CLP), the test item is not classified for skin or eye irritation.