2-tetradecyloxirane, reaction products with boric acid

Endpoint summary

Description of key information

Following challenge with 25 % test material in mineral oil, dermal scores of 1 were noted in 5/20 test animals at the 24-hour scoring interval and dermal scores of 1 or 2 were noted in 16/20 test animals at the 48 -hour scoring interval. The test item is classified as sensitising to the skin (OECD 406 and EPA OPPTS 870.2600).

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Remarks:

The test substance is surface active and with long alkyl chain, limitations for surfactant hat have been identified for the LLNA, thus the modified Buehler assay was adopted for the evaluation of sensitizing potential of the test substance.

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-07-02 to 2012-08-31

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

This study was conducted prior to the adoption of the in vitro/in chemico methods.

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2600 (Skin Sensitisation)

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes

Type of study:

Buehler test

Justification for non-LLNA method:

Conducted for other purposes outside of REACH.
The test substance is surface active and with long alkyl chain, limitations for surfactant hat have been identified for the LLNA, thus the modified Buehler assay was adopted for the evaluation of sensitizing potential of the test substance.

Species:

guinea pig

Strain:

Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Saint Constant, Quebec.
- Age at study initiation: First range-finding study (male: ca 5 weeks; female: ca 6 weeks); Second range-finding study (male: ca 9 weeks; female: ca 10 weeks); Main test (male: ca 6 weeks; female: ca 7 weeks)- Weight at study initiation: First range-finding study (male: 348 to 364 g; female: 329 to 356 g); Second range-finding study (male: 453 to 500 g; female: 476 to 545 g); Main test (male: 363 to 433 g; female: 340 to 437 g)
- Housing: Animals were paired housed throughout the study in solid bottom cages containing direct bedding material. As an alternative, guinea pigs were individually housed in solid bottom cages containing direct bedding material.
- Diet: PMI Nutrition International Certified Guinea Pig Chow® No. 5026, ad libitum
- Water: Municipal tap water following treatment by reverse osmosis and ultraviolet irradiation was available ad libitum
- Acclimation period: 7 days

ENVIRONMENTAL CONDITIONS
- Temperature: 20-22 °C
- Humidity: 53-65 %
- Air changes: 10 or more air changes per hour with 100 % fresh air
- Photoperiod: 12 h light / 12 h dark

IN-LIFE DATES: From: 2012-07-02 To: 2012-08-31

Route:

epicutaneous, occlusive

Vehicle:

unchanged (no vehicle)

Concentration / amount:

0.3 mL placed on a 25 mm Hilltop Chamber

Day(s)/duration:

1, 7 and 14

Adequacy of induction:

highest concentration used causing mild-to-moderate skin irritation and well-tolerated systemically

No.:

#1

Route:

epicutaneous, occlusive

Vehicle:

other: mineral oil

Concentration / amount:

25 %

Day(s)/duration:

28

Adequacy of challenge:

highest non-irritant concentration

No. of animals per dose:

- Range-finding test: 2 males and 2 females

Main test: 10 males and 10 females for test group; 5 males and 5 females for challenge control

Details on study design:

RANGE FINDING TESTS:- On Day 0, up to 4 closed chambers at 4 different concentrations of the test substance were prepared and a 0.33 g (100% concentration only) and 0.3 mL dose of each concentration was applied to the clipped area of each topical range-finding animal. The chambers were applied to the clipped surface as quickly as possible. The trunk of the animal was wrapped with elastic wrap which was secured with adhesive tape to prevent removal of the chambers and the animal was returned to its cage.- Approximately 6 hours after chamber application, the binding materials were removed. The test sites were then wiped 2 times with gauze moistened in mineral oil, followed by dry gauze and then wiped with gauze moistened in deionized water, followed by dry gauze, to remove test substance residue, and the animals were returned to their cages.MAIN STUDYA.

INDUCTION EXPOSURE:- No. of exposures: Three (Day 1, 7 and 14)- Exposure period: 6 hours- Test groups: 0.33 g (100 % concentration only) of the test substance was placed on a 25 mm Hilltop chamber backed by adhesive tape (occlusive patch). - Control group: None- Site: Left side of test animals- Frequency of applications: Once- Duration: Days 1-27- Concentrations: 100 %- Evaluation (hr after induction): 24 and 48 hoursB.

CHALLENGE EXPOSURE:- No. of exposures: One- Day(s) of challenge: Day 28- Exposure period: 6 hours- Test groups: 0.3 mL dose of the appropriate test substance was placed on a 25 mm Hilltop chamber backed by adhesive tape (occlusive patch). - Control group: 0.3 mL dose of the appropriate test substance was placed on a 25 mm Hilltop chamber backed by adhesive tape (occlusive patch). - Site: Right side of test animals- Concentrations: 25 %- Evaluation (hr after challenge): 24 and 48 hoursOTHER: - Mortality/moribundity checks: Animals were observed for general health/mortality and moribundity twice daily, once in the morning and afternoon, throughout the study.

- Dermal Observations: Test sites were graded for irritation at approximately 24 and 48 hours after chamber application (induction) or chamber removal (challenge) using the Macroscopic Dermal Grading System.
- Body Weights: Each topical range-finding animal was weighed on the day prior to dosing (Day -1). Each main study animal was weighed on the day prior to the first induction (Day -1), and on the day prior to challenge dosing for the appropriate test and challenge control animals.
- Scheduled Euthanasia: Following the 48-hour scoring interval, all surviving range-finding/main study animals were euthanized by carbon dioxide inhalation and discarded.

Challenge controls:

10 previously untreated (naive) challenge control guinea pigs were topically treated with 25 % test material (w/w) in mineral oil.

Positive control substance(s):

yes

Remarks:

HCA (Study no. 20029555)

Positive control results:

Study No. 20029555, an HCA positive control study, demonstrated that a valid test was performed and indicated that the test design would detect potential contact sensitizers.

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

100 % w/w induction and 25 % w/w challenge application

No. with + reactions:

5

Total no. in group:

20

Clinical observations:

dermal scores of 1 were noted

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 100 % w/w induction and 25 % w/w challenge application . No with. + reactions: 5.0. Total no. in groups: 20.0. Clinical observations: dermal scores of 1 were noted .

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

100 % w/w induction and 25 % w/w challenge application

No. with + reactions:

16

Total no. in group:

20

Clinical observations:

dermal scores of 1 or 2 were noted

Remarks on result:

other: see Remark

Remarks:

Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 100 % w/w induction and 25 % w/w challenge application . No with. + reactions: 16.0. Total no. in groups: 20.0. Clinical observations: dermal scores of 1 or 2 were noted .

Key result

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

25 % in mineral oil

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

2 males and 1 female with dermal irritation outside of the test site (likely due to binding tape).

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

25 % in mineral oil

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

1 male and 1 female with dermal irritation outside of the test site (likely due to binding tape). 1 male and 1 female with slight patchy erythema.

Remarks on result:

no indication of skin sensitisation

Key result

Reading:

other: Positive control study

Group:

positive control

Remarks on result:

positive indication of skin sensitisation

Remarks:

The positive control study demonstrated a valid test was performed.

Table 1: Individual challenge data

Group	Animal no./sex	Dermal scores
Test		25%^a
		24 hours	48 hours
	G5857/M	±^IT	1
	G5858/M	±	1
	G5859/M	±	1
	G5860/M	0	1
	G5861/M	1	2^ED-1
	G5862/M	1	1
	G5865/M	±	1
	G5866/M	0	±
	G5867/M	±	1
	G5868/M	1	1
	G5883/F	±	±
	G5884/F	0	0
	G5885/F	±	1
	G5886/F	±	1
	G5887/F	1	1
	G5888/F	±	1
	G5889/F	±	1
	G5890/F	±	±
	G5891/F	±	1
	G5892/F	1	1
	Mean	0.6	0.9
Challenge control	G5869/M	0	0
	G5870/M	0^IT	±
	G5871/M	0	0
	G5872/M	0	0
	G5875/M	0^IT	0^IT
	G5893/F	0	0
	G5894/F	0	0
	G5895/F	0	±
	G5896/F	0^IT	0^IT
	G5897/F	0	0
	Mean	0.0	0.0

 

^athe vehicle used was mineral oil; for purposes of calculation, ± = 0.5; ED-1: Edema - Grade 1 (Very slight edema (barely perceptible); IT: Dermal Irritation - Outside of the Test Site

Table 2: 1st Range Finding Test (topical irritation)

Animal	Concentration
	100%		75%		50%		25%
	24 hours	48 hours	24 hours	48 hours	24 hours	48 hours	24 hours	48 hours
Male G5855	0	±	0	±	0	0	0	0
Male G5856	0	0	0	0	0	0	0	0
Female G5881	0	±	0	0	0	0	0	0
Female GF882	±	1	0	±	0	±	0	±
Vehicle: Mineral oil

 

Table 3: 2nd Range Finding Test (topical irritation)

Animal	Concentration
	50%		30%		20%		10%
	24 hours	48 hours	24 hours	48 hours	24 hours	48 hours	24 hours	48 hours
Male G5873	±	±	0	±	±	±	0(IT)	±(IT)
Male G5874	0	±	0	0	0(IT)	0(IT)	0(IT)	0(IT)
Female G5905	0	0	0	0	0	0	0	0
Female GF5906	0	0	0	0	0(IT)	0(IT)	0(IT)	0(IT)
Vehicle: Mineral oil

Interpretation of results:

sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Under these test conditions is classified as sensitizing to the skin according to the CLP Regulation (EC) No. 1272/2008.

Executive summary:

Test Guidance

In a Guinea Pigs-Modified Buehler test performed according to OECD Guideline 406 and in compliance with GLP.

Method and materials

10 male and 10 female Hartley derived albino guinea pigs were topically treated with 100% (as received) once per week, for 3 consecutive weeks. Following a 2-week rest period, a challenge was performed whereby the 20 test and 10 previously untreated (naive) challenge control guinea pigs were topically treated with 25 % (w/w) in mineral oil. Challenge responses in the test animals were compared to those of the challenge control animals. Exposure to test material at concentrations of 25, 50, 75 and 100 % resulted in dermal scores of 0, ±, or 1. Therefore, induction was determined to be acceptable at 100 % (as received). A second range-finding study conducted at concentrations of 10, 20, 30 and 50 % to determine an appropriate challenge level resulted in dermal scores of 0 or ±. Therefore, challenge was determined to be acceptable at 25 % (w/w) in mineral oil, based on the results of the 2 range-finding studies.

Results

No mortality was observed during the study. Following challenge with 25 % test material in mineral oil, dermal scores of 1 were noted in 5/20 test animals at the 24 -hour scoring interval and dermal scores of 1 or 2 were noted in 16/20 test animals at the 48 -hour scoring interval. Group mean dermal scores were higher in the test animals compared to the challenge control animals. Historical data on positive control (HCA) demonstrated a validity of the test.

Conclusions

Under these test conditions, test item is classified as sensitizing to the skin according to the CLP Regulation (EC) No.1272/2008.

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

In a key modified Buehler test performed on guinea pigs according to OECD Guideline 406, 10 male and 10 female Hartley derived albino guinea pigs were topically treated with 100% (as received) test material once per week, for 3 consecutive weeks. Following a 2-week rest period, a challenge was performed whereby the 20 test and 10 previously untreated (naive) challenge control guinea pigs were topically treated with 25 % (w/w) in mineral oil. Challenge responses in the test animals were compared to those of the challenge control animals. Exposure to the test material at concentrations of 25, 50, 75 and 100 % resulted in dermal scores of 0, ±, or 1. Therefore, induction was determined to be acceptable at 100 % (as received). A second range-finding study conducted at concentrations of 10, 20, 30 and 50 % to determine an appropriate challenge level resulted in dermal scores of 0 or ±. Therefore, challenge was determined to be acceptable at 25 % (w/w) in mineral oil, based on the results of the 2 range-finding studies.

No mortality was observed during the study. Following challenge with 25 % test material in mineral oil, dermal scores of 1 were noted in 5/20 test animals at the 24 -hour scoring interval and dermal scores of 1 or 2 were noted in 16/20 test animals at the 48 -hour scoring interval. Group mean dermal scores were higher in the test animals compared to the challenge control animals. Historical data on positive control (HCA) demonstrated a validity of the test. Under these test conditions, test item is classified as sensitizing to the skin according to the CLP Regulation (EC) No.1272/2008.

Justification for classification or non-classification

Following challenge with 25% test material in mineral oil, dermal scores of 1 were noted in 5/20 test animals at the 24 -hour scoring interval and dermal scores of 1 or 2 were noted in 16/20 test animals at the 48 -hour scoring interval. Group mean dermal scores were higher in the test animals compared to the challenge control animals. Under these test conditions, the test item is classified as sensitizing to the skin according to the CLP Regulation (EC) No.1272/2008.