2,2'-butyliminodiethanol

Endpoint summary

Description of key information

- Buehler Test (OECD 406, GLP): guinea pigs (Hartley, m/f), undiluted (induction), 50 % w/v in distilled water (challenge), 50 % and 1 % w/v in distilled water (re-challenge). 1 positive responder at challenge (50 %) and another one positive responder at re-challenge (50 %); No positive responders at 1 %. The overall result: BDEA does not trigger C&L as skin sensitizer.

Key value for chemical safety assessment

Skin sensitisation

Link to relevant study records

Reference

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

August 14, 1995 to December 22, 1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study.

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EEC Council directive 67/548/EEC, September 19, 1984

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OTS 798.4100 (Skin Sensitisation)

Deviations:

no

Principles of method if other than guideline:

no deviations which would compromise the validity of the study.

GLP compliance:

yes

Remarks:

EPA TSCA GLP guidelines (40 CFR Part 792) and OECD GLP's "OECD Principles of Good Laboratory Practice, C(81)30(Final)Annex 2. May 12, 1981.

Type of study:

Buehler test

Justification for non-LLNA method:

The Buehler test (in vivo) was performed before the LLNA was set as preferred test method.

Species:

guinea pig

Strain:

Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: from a U.S.D.A. licensed supplier (Animal Supplier: Harlan Sprague Dawley, Inc. P.O. Box 29176 Indianapolis, Indiana 46229)
- Age at study initiation: young adult
- Weight at study initiation: 342 to 467 grams
- Housing: individually in wire mesh suspension cages
- Diet (e.g. ad libitum): ad libitum (Teklad Guinea Pig Diet)
- Water (e.g. ad libitum): ad libitum (tap water)
- Acclimation period: at least 4 days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: August 29, 1995 To: October 16, 1995

Route:

epicutaneous, occlusive

Vehicle:

water

Remarks:

Undiluted distilled

Concentration / amount:

- Pilot test: undiluted, 50 %, 25 %, 10 %, 5 %, 2.5 %, 1.0 %, and 0.5 %;
- Main test: 50 % (challenge);
- Main test: 50 % and 1 % (re-challenge).

Route:

epicutaneous, occlusive

Vehicle:

water

Remarks:

Undiluted distilled

Concentration / amount:

- Pilot test: undiluted, 50 %, 25 %, 10 %, 5 %, 2.5 %, 1.0 %, and 0.5 %;
- Main test: 50 % (challenge);
- Main test: 50 % and 1 % (re-challenge).

No. of animals per dose:

- Pilot test: 8 animals (two groups of four animals each);
- Main test: 20 (test animals); 10 (vehicle control animals)

Details on study design:

RANGE FINDING TESTS:
Irritation Screening (Pilots):
The irritation phase had the purpose of determining the proper level of test material to be used in the induction and challenge phase. The irritation potential of Butyldiethanolamine 1029 at levels of undiluted, 50 %, 25 %, 10 %, 5 %, 2.5 %, 1.0 %, and 0.5 % was evaluated in two groups of four animals each. Four levels of test material were evaluated per animal, such that each animal in a given pilot group was exposed to the same levels. Dilutions of the test material were prepared w/v in distilled water. The position of the different concentrations of the test material on the animals was varied to adjust for possible site-to-site variation in response (See diagram below for available skin sites, attached to this file).
The day prior to test material exposure, the hair was removed from each of the animal's backs using a small animal clipper. Closed patches were applied to the animals in the following manner: A 0.3 mL amount of each test preparation was applied into a 25 mm Hill Top Chamber® (This 0.3 mL volume is reduced from the 0.5 mL volume referenced in the EEC Guidelines due to the volume limit of the 25 mm Hill Top Chamber®). The animal was placed into the restrainer and the chamber(s) were applied to the clipped surface as quickly as possible. The chamber(s) were occluded with rubber dental dam pulled taut and fastened to the bottom of the restrainer with clips. The restrainer was adjusted to minimize movement of the animal during exposure. Approximately six hours later (± 15 minutes), the dental dam and chamber(s) were removed, the animal was taken from the restrainer, and placed in its cage. The day following the irritation exposure all animals were depilated and scored.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: 3
- Exposure period: 6 hours
- Test and control groups:
The left shoulder (Site 1) of each animal was clipped with a small animal clipper the day before exposure (See diagram below for skin site, attached to this file). The clipped areas were exposed to the respective test or vehicle material and the animals were restrained as previously described under "Irritation Screening". The procedure was repeated at the same site once every seven days for the next fourteen days for a total of three approximate six-hour exposures (± 15 minutes). (See Protocol Deviations section Page 20 of report). Induction sites were graded approximately 24 hours (± 15 minutes) after completion of each induction exposure using the grading scale described under "Observations". After the last induction exposure, the animals were left untreated for fourteen days before primary challenge.
- Site: 1(left shoulder)
- Frequency of applications: once every seven days
- Duration: 14 days
- Concentrations: undiluted

B. CHALLENGE EXPOSURE
- No. of exposures: 1
- Day(s) of challenge: fourteen days after the last induction exposure.
- Exposure period: 6 hours
- Test and control groups: The same exposure procedure was used as for the "Induction Phase", but the chambers were applied to the test animals and vehicle animals at the lower left flank (Site 2).The patch sites were varied to adjust for possible site-to-site variation in response. (See diagram below for available skin sites, attached to this file).
- Site: 2 (lower left flank)
- Concentrations: 50 % (w/v in distilled water)
- Evaluation (hr after challenge): 24 and 48

OTHER: RE-CHALLENGE (see in "Any other information on materials and methods").

Challenge controls:

The vehicle control animals were common to this study and studies 95-8736-21 and 95-8737-21; at the challenge, they received one patch of each test material using Sites 2, 4, and 5, respectively.

Positive control substance(s):

yes

Remarks:

routinely analysed at the test facility

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

50 %

No. with + reactions:

1

Total no. in group:

20

Clinical observations:

slight but confluent, or moderate patchy erythema (score of 1).

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 50 %. No with. + reactions: 1.0. Total no. in groups: 20.0. Clinical observations: slight but confluent, or moderate patchy erythema (score of 1).

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

50 %

No. with + reactions:

1

Total no. in group:

20

Clinical observations:

slight but confluent, or moderate patchy erythema (score of 1)

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 50 %. No with. + reactions: 1.0. Total no. in groups: 20.0. Clinical observations: slight but confluent, or moderate patchy erythema (score of 1).

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

50 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no positive responders with score of 1

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 50 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no positive responders with score of 1.

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

50 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no positive responders with score of 1

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 50 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no positive responders with score of 1.

Reading:

rechallenge

Hours after challenge:

24

Group:

test chemical

Dose level:

50 %

No. with + reactions:

1

Total no. in group:

20

Clinical observations:

slight but confluent, or moderate patchy erythema (score of 1)

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 24.0. Group: test group. Dose level: 50 %. No with. + reactions: 1.0. Total no. in groups: 20.0. Clinical observations: slight but confluent, or moderate patchy erythema (score of 1).

Reading:

rechallenge

Hours after challenge:

48

Group:

test chemical

Dose level:

50 %

No. with + reactions:

1

Total no. in group:

20

Clinical observations:

slight but confluent, or moderate patchy erythema (score of 1)

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 48.0. Group: test group. Dose level: 50 %. No with. + reactions: 1.0. Total no. in groups: 20.0. Clinical observations: slight but confluent, or moderate patchy erythema (score of 1).

Reading:

rechallenge

Hours after challenge:

24

Group:

test chemical

Dose level:

1 %

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

no positive responders with score of 1.

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 24.0. Group: test group. Dose level: 1 %. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: no positive responders with score of 1..

Reading:

rechallenge

Hours after challenge:

48

Group:

test chemical

Dose level:

1 %

No. with + reactions:

0

Total no. in group:

20

Clinical observations:

no positive responders with score of 1

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 48.0. Group: test group. Dose level: 1 %. No with. + reactions: 0.0. Total no. in groups: 20.0. Clinical observations: no positive responders with score of 1.

Reading:

rechallenge

Hours after challenge:

24

Group:

negative control

Dose level:

50 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no positive responders with score of 1

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 24.0. Group: negative control. Dose level: 50 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no positive responders with score of 1.

Reading:

rechallenge

Hours after challenge:

48

Group:

negative control

Dose level:

50 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no positive responders with score of 1

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 48.0. Group: negative control. Dose level: 50 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no positive responders with score of 1.

Reading:

rechallenge

Hours after challenge:

24

Group:

negative control

Dose level:

1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no positive responders with score of 1

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 24.0. Group: negative control. Dose level: 1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no positive responders with score of 1.

Reading:

rechallenge

Hours after challenge:

48

Group:

negative control

Dose level:

1 %

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

no positive responders with score of 1

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 48.0. Group: negative control. Dose level: 1 %. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: no positive responders with score of 1.

Group:

positive control

Remarks on result:

other: routinely analysed at the test facility

Results of the primary irritation, induction, primary challenge, and rechallenge applications are presented in Tables 1 through 7, respectively (please see attached to this file).

Individual body weight data are presented in Table 8.

Interpretation of results:

not sensitising

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

According to the criteria of significant skin sensitizing effects outlined in the Guidance on the Application of Regulation (EC) No. 1272/2008 (2013), a substance should be considered as sensitizing in the Buehler occluded patch test if redness is observed in >= 15 % of the test animals. Butyldiethanolamine as 50 % dilution induced a positive response (score of 1 = slight but confluent, or moderate patchy erythema) at both reading time points in one animal at challenge and in another one animal at re-challenge. However, 1 out of 20 animals amounts to 5 %. Moreover, no positive responders were observed at rechallenge with 1 % of butyldiethanolamine.
Therefore, Butyldiethanolamine did not induce a significant skin sensitisation effect and does not need to be classified and labelled as skin sensitiser in accordance with Regulation (EC) No. 1272/2008.

Executive summary:

The test material, Butyldiethanolamine 1029, was evaluated for primary irritation at levels of undiluted, 50 %, 25 %, 10 %, 5 %, 2.5 %, 1 %, and 0.5 %. All formulations were prepared w/v in distilled jwater. The 50 % formulation formed a clear solution with a yellow tint which decreased in color to clear colorless solutions as the concentrations decreased. Undiluted Butyldiethanolamine 1029 produced grades of 1, 50 %, 25 %, and 5 % produced grades of ±, while 10 %, 2.5 %, 1 %, and 0.5 % produced grades of ± and 0. An undiluted concentration of Butyldiethanolamine 1029 was chosen for use at induction for the test group. This level was chosen as the highest concentration causing no greater than mild to moderate primary irritation. Undiluted distilled water was utilized at induction for the vehicle control group. A 50 % w/v concentration of Butyldiethanolamine 1029 in distilled water was chosen for use at primary challenge for the test group and the vehicle control group. This level was chosen as the highest concentration causing no more than slight primary irritation. The incidence and severity of responses were calculated as follows:

Group	Material^a	CONC^bc	Incidence of Responses										Mean Severity Scores
			24-Hours					48-Hours
			0	±	1	2	3	0	±	1	2	3	24-hr	48-hr
Primary Challenge
Test	TMID	50 %	2	17	1	0	0	8	11	1	0	0	0.5	0.3
Vehicle Control	TMID	50 %	2	7	0	0	0	7	2	0	0	0	0.4	0.1
Re-challenge
Test	TMID	50 %	7	12	1	0	0	6	13	1	0	0	0.4	0.4
	TMID	1 %	12	8	0	0	0	15	5	0	0	0	0.2	0.1
Vehicle Control	TMID	50 %	3	6	0	0	0	7	2	0	0	0	0.3	0.1
	TMID	1 %	6	3	0	0	0	7	2	0	0	0	0.2	0.1

^aTMID - BUTYLDIETHANOLAMINE 1029.

^bCONC = Concentration.

^cTest material formulated w/v in distilled water.

A single test animal (T-13) had a grade 1 response at challenge and another test animal (T-20) responded at rechallenge to the 50 % dilution of test material but not to 1 %. Both responses are suggestive of sensitization. No control animal responded with a grade 1, suggesting that sensitization had occurred.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not sensitising)

Additional information:

Butyldiethanolamine was evaluated for its skin sensitisation potential in a Buehler Test (OECD 406; Elf Atochem North America Inc., 1995, Report No.95-8735-21). In a pilot test, primary irritation of BDEA was tested at levels of undiluted, 50 %, 25 %, 10 %, 5 %, 2.5 %, 1 %, and 0.5 %. All formulations were prepared w/v in distilled water. The 50% formulation formed a clear solution with a yellow tint which decreased in colour to clear colourless solutions as the concentrations decreased. Undiluted BDEA produced grades of 1 (slight but confluent, or moderate patchy erythema), 50 %, 25 %, and 5 % produced grades of ± (slight, patchy erythema), while 10 %, 2.5 %, 1 %, and 0.5 % produced grades of ± and 0 (no reaction). An undiluted concentration of BDEA was chosen for use at induction for the test group. This level was chosen as the highest concentration causing no greater than mild to moderate primary irritation. Undiluted distilled water was utilized at induction for the vehicle control group. A 50 % w/v concentration of BDEA in distilled water was chosen for use at primary challenge for the test group and the vehicle control group. This level was chosen as the highest concentration causing no more than slight primary irritation. A 50 % and 1% w/v concentration of BDEA in distilled water were chosen for use at re-challenge for the test group and the vehicle control group.

A single test animal (T-13) had a grade 1 response at challenge and another test animal (T-20) responded at re-challenge to the 50% dilution of test material, but no positive responders were observed to the 1 % dilution. According to the interpretation criteria presented in the study report, both responses are suggestive of sensitization. No control animal responded with a grade 1, suggesting that sensitization had occurred.

Justification for selection of skin sensitisation endpoint:
Best study available

Justification for classification or non-classification

According to the criteria of significant skin sensitizing effects outlined in the Guidance on the Application of Regulation (EC) No. 1272/2008 (2013), a substance should be considered as sensitizing in the Buehler occluded patch test if redness is observed in >= 15 % of the test animals. Butyldiethanolamine as 50 % dilution induced a positive response (score of 1 = slight but confluent, or moderate patchy erythema) at both reading time points in one animal at challenge and in another one animal at re-challenge. However, 1 out of 20 animals amounts to 5 %. Moreover, no positive responders were observed at rechallenge with 1 % of Butyldiethanolamine. Thus, Butyldiethanolamine is considered as not sensitizer because it did not induce a significant skin sensitisation effect in treated animals (positive response in < 15% of the test animals) and therefore does not need to be classified and labelled as skin sensitiser in accordance with Regulation (EC) No. 1272/2008.