Mercaptoacetic acid, monoester with propane-1,2,3-triol

Skin sensitisation

Administrative data

Endpoint:

skin sensitisation: in vivo (non-LLNA)

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1998

Report date:

1998

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Department of health of the government of the United Kingdom

Type of study:

guinea pig maximisation test

Justification for non-LLNA method:

At that time, no OECD guideline on LLNA method had been published.

Test material

Test material information

Constituent 1

Reference substance name:

Mercaptoacetic acid, monoester with propane-1,2,3-triol

EC Number:

250-264-8

EC Name:

Mercaptoacetic acid, monoester with propane-1,2,3-triol

Cas Number:

30618-84-9

Molecular formula:

C5H10O4S

IUPAC Name:

2,3-dihydroxypropyl 2-sulfanylacetate

Test material form:

solid - liquid: suspension

Details on test material:

- Name of test material (as cited in study report): Glyceryl Thioglycolate 80 %
- Analytical purity: 80.2 %

In vivo test system

Test animals

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: David Hall Limited, Burton-on-Trent, Staffordshire, UK
- Age at study initiation: 8 - 12 weeks
- Weight at study initiation: 316 - 390 g
- Housing: Single or in pairs in solid-floor polypropylene cages furnished with woodflakes
- Diet: Ad libitum
- Water: Ad libitum
- Acclimation period: 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18 - 22
- Humidity (%): 37 - 58
- Air changes (per hr): 15
- Photoperiod (hrs dark / hrs light): 12 / 12

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal and epicutaneous

Vehicle:

water

Induction 2

Concentration / amount:

- Intradermal induction : 1% w/v of the supplied test material in distilled water
- Topical lnduction : 10% v/v of the supplied test material in distilled water
- Topical Challenge : 10% and 5% v/v of the supplied test material in distilled water

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

water

Challenge 2

Concentration / amount:

- Intradermal induction : 1% w/v of the supplied test material in distilled water
- Topical lnduction : 10% v/v of the supplied test material in distilled water
- Topical Challenge : 10% and 5% v/v of the supplied test material in distilled water

No. of animals per dose:

Twenty test (10 male, 10 female) and ten control animals (5 male, 5 female)

Details on study design:

RANGE FINDING TESTS:
- The highest concentration that caused only mild to moderate skin irritation, and which was well tolerated systemically, was selected for the intradermal induction stage of the main study.
- The highest concentration producing only mild to moderate dermal irritation was selected for the TOPICAL induction stage of the main study.
- The highest non-irritant concentration of the test material and one lower concentration were selected for the topical challenge stage of the main study.

MAIN STUDY
A. INDUCTION EXPOSURE
- No. of exposures: Intradermal and topical induction
- Intradermal: 3 single Injections: a) Freund’s Complete Adjuvant plus distilled water in the ratio 1:1
b) a 1% w/v formulation of the supplied test material in distilled water
c) a 1% w/v formulation of the supplied test material in a 1:1 preparation of Freund’s Complete Adjuvant in distilled water
- Topical induction: 7 days after intradermal induction: Occlusive dressing with 10% v/v in distilled water for 48 h
- Control animals where treated in the same manner with vehicle instead of test material
- As the test material showed evidence for skin irritation, no local irritation by sodium lauryl sulphate was created.
B. CHALLENGE EXPOSURE
- Exposure period: 24 h
- Test groups: 5 and 10% v/v of the supplied test material in distilled water
- Control group: Vehicle
- Evaluation (hr after challenge): Approximately 24, 48 and 72 hours after challenge dressing removal, the degree of erythema and oedema was quantified.

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

1st reading

Hours after challenge:

24

Group:

test chemical

Dose level:

10 % v/v

No. with + reactions:

9

Total no. in group:

20

Clinical observations:

erythema and oedema formation up to score of 2

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: test group. Dose level: 10 % v/v. No with. + reactions: 9.0. Total no. in groups: 20.0. Clinical observations: erythema and oedema formation up to score of 2.

Results 2

Reading:

1st reading

Hours after challenge:

24

Group:

negative control

Dose level:

10% v/v

No. with + reactions:

0

Total no. in group:

10

Clinical observations:

none

Remarks on result:

other: Reading: 1st reading. . Hours after challenge: 24.0. Group: negative control. Dose level: 10% v/v. No with. + reactions: 0.0. Total no. in groups: 10.0. Clinical observations: none.

Results 3

Reading:

2nd reading

Hours after challenge:

48

Group:

test chemical

Dose level:

10 % v/v

No. with + reactions:

10

Total no. in group:

20

Clinical observations:

erythema and oedema formation up to score of 2, desquamation

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: test group. Dose level: 10 % v/v. No with. + reactions: 10.0. Total no. in groups: 20.0. Clinical observations: erythema and oedema formation up to score of 2, desquamation.

Results 4

Reading:

2nd reading

Hours after challenge:

48

Group:

negative control

Dose level:

10% v/v

No. with + reactions:

5

Total no. in group:

10

Clinical observations:

no erythema or edema, only slight desquamation

Remarks on result:

other: Reading: 2nd reading. . Hours after challenge: 48.0. Group: negative control. Dose level: 10% v/v. No with. + reactions: 5.0. Total no. in groups: 10.0. Clinical observations: no erythema or edema, only slight desquamation.

Any other information on results incl. tables

INDIVIDUAL SKIN REACTIONS AT TEST ANIMALS AT CHALLENGE

	24 h first reading						48 h second reading						72 h third reading
	5 %			10%			5 %			10%			5 %			10%
Animal	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other
1	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*	*
2	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
3	1	0	-	1	0	-	0	0	-	0	0	D	0	0	-	0	0	D
4	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
5	1	1	-	2	1	-	1	0	-	0	1	-	0	0	-	1	0	D
6	1	1	-	2	1	-	1	1	-	2	1	D	0	0	D	0	0	D
7	0	0	-	0	0	-	0	0	D	0	0	D	0	0	D	0	0	D
8	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
9	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
10	1	0	-	2	1	-	0	0	-	1	1	D	0	0	D	0	0	D
11	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	1	1	-
12	1	1	-	1	1	-	1	0	-	1	1	D	0	0	D	0	0	D
13	1	1	-	1	1	-	1	0	-	1	1	-	0	0	D	0	0	D
14	0	0	-	1	1	-	0	0	-	2	1	-	0	0	-	0	0	D
15	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
16	0	0	-	0	0	-	#	#	#	#	#	#	#	#	#	#	#	#
17	1	1	-	2	2	-	1	1	D	2	2	D	0	0	D	0	0	D
18	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
19	0	0	-	0	0	-	0	0	-	1	0	-	0	0	-	0	0	-
20	1	1	-	1	1	-	1	1	D	1	0	-	0	0	D	0	0	D

Er = Erythema, Oe = Oedema, - = no other reactions noted, D = desquamation, * = no data; animal killed for humane reasons on Day 20, # = no data; animal found dead on Day 24

INDIVIDUAL SKIN REACTIONS AT CONTROL ANIMALS AT CHALLENGE

	24 h first reading						48 h second reading						72 h third reading
	5 %			10%			5 %			10%			5 %			10%
Animal	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other	Er	Oe	Other
21	0	0	-	0	0	-	0	0	-	0	0	-	0	0	D	0	0	-
22	0	0	-	0	0	-	0	0	-	0	0	D	0	0	D	0	0	D
23	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
24	0	0	-	0	0	-	0	0	-	0	0	D	0	0	-	0	0	D
25	0	0	-	0	0	-	0	0	-	0	0	D	0	0	D	0	0	D
26	0	0	-	0	0	-	0	0	-	0	0	D	0	0	-	0	0	D
27	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-
28	0	0	-	0	0	-	0	0	-	0	0	D	0	0	-	0	0	D
29	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	D
30	0	0	-	0	0	-	0	0	-	0	0	-	0	0	-	0	0	D

Er = Erythema, Oe = Oedema, - = no other reactions noted, D = desquamation,

Applicant's summary and conclusion

Interpretation of results:

Category 1 (skin sensitising) based on GHS criteria

Remarks:

Migrated information

Conclusions:

GMT is a moderate sensitizer to guinea pig skin.