Benzoic acid, 5-amino-2-chloro-, 1,1-dimethyl-2-oxo-2-(2-propen-1-yloxy)ethyl ester

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)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 406 (Skin Sensitisation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of study:

guinea pig maximisation test

Test material

Test material information

Constituent 1

Reference substance name:

prop-2-en-1-yl 2-(5-amino-2-chlorobenzoyloxy)-2-methylpropanoate

EC Number:

696-318-8

Cas Number:

174489-43-1

Molecular formula:

C14H16ClNO4

IUPAC Name:

prop-2-en-1-yl 2-(5-amino-2-chlorobenzoyloxy)-2-methylpropanoate

In vivo test system

Test animals

Species:

guinea pig

Strain:

other: Himalayan Spotted (GOH)

Sex:

male/female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: BRL Biological Research Laboratories, Wölferstrasse 4, 4414 Füllinsdorf / Switzerland
- Age at study initiation: Young adult (approximately 1 - 3 months
- Weight at study initiation: 352 - 441 g
- Housing: Individual
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 3 ° C
- Humidity (%): 50 % ± 20 %
- Air changes (per hr): 13 - 14/hour
- Photoperiod (hrs dark / hrs light): 12/12/hours

The animal were distributed as follows:

Number of animals per group
1 Control Group 10
2 Test Group 20
3 Intradermal Pre-test 2
4 Epidermal Pre-test 2

Study design: in vivo (non-LLNA)

Induction

Induction 1

Route:

intradermal

Vehicle:

other: Refer to concentration section

Induction 2

Concentration / amount:

Intradermal Induction Pre-test: 0.5, 1.0, 3.0 and 5.0 % in peanut oil

Epidermal Induction Pre-test; 30, 50, 80 in vaseline and 100 % (undiluted)

Day 0 – Intradermal Induction Injections: 5.0 % in peanut oil

Day 8 – Epidermal Application Induction: 80 % in Vaseline

Day 21 – Epidermal Challenge: 30 % in Vaseline

Challenge

Challenge 1

Route:

epicutaneous, occlusive

Vehicle:

other: Refer to concentration section

Challenge 2

Concentration / amount:

Intradermal Induction Pre-test: 0.5, 1.0, 3.0 and 5.0 % in peanut oil

Epidermal Induction Pre-test; 30, 50, 80 in vaseline and 100 % (undiluted)

Day 0 – Intradermal Induction Injections: 5.0 % in peanut oil

Day 8 – Epidermal Application Induction: 80 % in Vaseline

Day 21 – Epidermal Challenge: 30 % in Vaseline

No. of animals per dose:

Number of animals per group
1 Control Group 10
2 Test Group 20
3 Intradermal Pre-test 2
4 Epidermal Pre-test 2

Details on study design:

Pre-tests, Intradermal Induction
Injections of 0.5, 1.0, 3.0, and 5.0% CA 2219 A in peanut oil produced irritation at the injection site for all concentrations. The 5.0% concentration was selected for the induction injection for the definitive test, in that it was suitable for injection, systematically well tolerated, and produced mild to moderate skin irritation. Individual irritation scores are presented in Table 1.

Pre-test, Epidermal Application
Epidermal application of 30, 50, 80and 100% (undiluted) concentrations produced skin irritation at 50 % (male animal), 80 % (both sexes) and 100 % (male animal). The 80 % concentration was selected for epidermal induction as the highest concentration to produce mild to moderate irritation in both sexes. The 30 % concentration was the only concentration to produce no irritation (highest non-irritant dose), and was therefore selected for the epidermal challenge application. Individual irritation scores are presented in Table 2.

Maximisation Test Procedure:

The Maximisation test was conducted with 10 animals in the vehicle control group and 20 animals in the test article group.

A set of intradermal induction injections was made on day 0. Vehicle control group injections: (1) adjuvant/physiological saline mixture, 1:1 v/v
(2) peanut oil
(3) peanut oil, 50% v/v with 1:1 adjuvant/
physiological saline mixture
Test article group injections: (1) adjuvant/physiological saline mixture, 1:1 v/v
(2) CA 2219 A in peanut oil
(3) CA 2219 A in 1:1 adjuvant/physiological saline
mixture

An epidermal induction application was made on Day 8.

The challenge epidermal application was made once on Day 21.

Positive control substance(s):

no

Results and discussion

In vivo (non-LLNA)

Results

Results 1

Reading:

other: Sensitization

Hours after challenge:

24

Group:

other: Control

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: other: Sensitization. . Hours after challenge: 24.0. Group: other: Control. No with. + reactions: 0.0. Total no. in groups: 10.0.

Results 2

Reading:

other: Sensitization

Hours after challenge:

24

Group:

test chemical

No. with + reactions:

16

Total no. in group:

20

Remarks on result:

other: Reading: other: Sensitization. . Hours after challenge: 24.0. Group: test group. No with. + reactions: 16.0. Total no. in groups: 20.0.

Results 3

Reading:

other: Sensitisation

Hours after challenge:

48

Group:

other: Control

No. with + reactions:

0

Total no. in group:

10

Remarks on result:

other: Reading: other: Sensitisation. . Hours after challenge: 48.0. Group: other: Control. No with. + reactions: 0.0. Total no. in groups: 10.0.

Results 4

Reading:

other: Sensitization

Hours after challenge:

48

Group:

test chemical

No. with + reactions:

15

Total no. in group:

20

Remarks on result:

other: Reading: other: Sensitization. . Hours after challenge: 48.0. Group: test group. No with. + reactions: 15.0. Total no. in groups: 20.0.

Any other information on results incl. tables

Skin Irritation Check

To document irritation by the test article during epidermal induction, sites were examined 1 hour after removal of the dressing for the epidermal induction. Positive skin irritation reactions were noted for all animals in the CA 2219 A group. There were no positive reactions among the vehicle control group animals. Results are presented in Table 3. 

Table 3: Skin Irritation Check After Epidermal Induction

Day 10, Observations 1 hour after patch removal

VEHICLE CONTROL		TEST ARTICLE
SEX/ANIMAL#	REACTION	SEX/ANIMAL#	REACTION
M/1	-	M/6	+
M/2	-	M/7	+
M/3	-	M/8	+
M/4	-	M/9	+
M/5	-	M/10	+
		M/11	+
		M/12	+
		M/13	+
		M/14	+
		M/15	+
F/16	-	F/21	+
F/17	-	F/22	+
F/18	-	F/23	+
F/19	-	F/24	+
F/20	-	F/25	+
		F/26	+
		F/27	+
		F/28	+
		F/29	+
		F/30	+

-      = negative

+   = positive

Skin Reaction following Challenge Application

Positive reactions on the test flanks were observed in 8 males and 8 females of the test group animals at the 24 hour examination and in 6 males and 9 females at the 48-hour examination; the sensitization rate for CA 2219 A (Intermediate of CGA 276854) was therefore 80%. Scaling was seen in three males and three females at the 48 hour observation. There were no positive skin responses at the vehicle flanks and among the vehicle control group. 

Sensitization reactions are summarized in table 4.

Individual animal Draize scores are present in Tables 5 and 6 for vehicle control and CA 2219 A group animals, respectively. 

 

Table 4: Summary of Positive Skin Reactions after Challenge Application

Number of Animals with Positive Responses/Number of Animals in Group

	VEHICLE FLANK		TEST FANK
	24 HOURS	48 HOURS	24 HOURS	48 HOURS
CONTROL GROUP	0/10	0/10	0/10	0/10
TEST ARTICLE GROUP	0/20	0/20	16/20	15/20

 

Note : Vehicle was vaseline for both control and CA 2219 A (Intermediate of CGA 276854) groups. 

Table 5: Individual Challenge Skin Reactions, Vehicle Control Group

Driaze Scores

SEX/ANIMAL#		VEHICLE FLANK					TEST FLANK
		24 HOURS			48 HOURS		24 HOURS		48 HOURS
		ERYTHEMA		EDEMA	ERYTHEMA	EDEMA	ERYTHEMA	EDEMA	ERYTHEMA	EDEMA
M/1		0		0	0	0	0	0	0	0
M/2		0		0	0	0	0	0	0	0
M/3		0		0	0	0	0	0	0	0
M/4		0		0	0	0	0	0	0	0
M/5		0		0	0	0	0	0	0	0
F/16	0		0		0	0	0	0	0	0
F/17	0		0		0	0	0	0	0	0
F/18	0		0		0	0	0	0	0	0
F/19	0		0		0	0	0	0	0	0
F/20	0		0		0	0	0	0	0	0

Note: vehicle was vaseline

Table 6: Individual Challenge Skin Reactions, Test Article Group

Draize Scores

SEX/ANIMAL#	VEHICLE FLANK				TEST FLANK
	24 HOURS		48 HOURS		24 HOURS		48 HOURS
	ERYTHEMA	EDEMA	ERYTHEMA	EDEMA	ERYTHEMA	EDEMA	ERYTHEMA	EDEMA
M/6	0	0	0	0	3	3	3	3
M/7	0	0	0	0	2	2	2	1
M/8	0	0	0	0	2	2	2	1
M/9	0	0	0	0	2	2	2	1
M/10	0	0	0	0	0	0	0	0
M/11	0	0	0	0	3	3	3	3
M/12	0	0	0	0	2	3	3	2
M/13	0	0	0	0	1	0	0	0
M/14	0	0	0	0	1	0	0	0
M/15	0	0	0	0	0	0	0	0
F/21	0	0	0	0	0	0	01	0
F/22	0	0	0	0	1	1	2	1
F/23	0	0	0	0	2	1	2	1
F/24	0	0	0	0	2	1	2	1
F/25	0	0	0	0	3	2	3	3
F/26	0	0	0	0	2	1	2	1
F/27	0	0	0	0	1	1	1	1
F/28	0	0	0	0	3	2	3	2
F/29	0	0	0	0	0	0	0	0
F/30	0	0	0	0	1	0	1	1

Note: vehicle was Vaseline. Scaling was noted for animals 6, 11, 12, 24, 24 and 28 on the test flank at the 48-hour reading. 

There was no mortality in the test.

There were no remarkable clinical observations.

Body weights were not affected by treatment.

Applicant's summary and conclusion

Interpretation of results:

other: ‘May cause sensitization by skin contact’

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

According to the test results, CA 2219 A (Intermediate of CGA 276854) is required to be classified as ‘May cause sensitization by skin contact’ according to Commission Directive 93/21/EEC, issued May 4, 1993.

Executive summary:

A dermal sensitization test was conducted with CA 2219 A (Intermediate of CGA 276854) batch 249-GE001/SU) using the Maximization procedure. Two groups of guinea pigs (10 vehicle control, 20 test) were included. On day 0, the test group animals were given a set of intradermal injections including (including 5.0% CA 2219 A (Intermediate of CGA 276854) in peanut oil for the test group). The epidermal induction application was made on day 8; the vehicle control animals were treated with the vehicle alone, and the test animals with 80% CA 2219 A (Intermediate of CGA 276854) in vaseline. The epidermal challenge application on day 21 consisted of a paired application of the vehicle alone and 30% CA 2219 A (Intermediate of CGA 276854) in vaseline in both groups. Skin reactions on both the vehicle and test flanks were scored 24 and 48 hours after completion of the challenge application, according to the Draize scale. 

 

Positive reactions on the test flanks were only observed in 8 males and 8 females of the test group animals at the 24 hour examination and in 6 males and 9 females at the 48-hour examination; the sensitization rate for CA 2219 A (Intermediate of CGA 276854) was therefore 80%. Scaling was seen in three males and three females at the 48 hour observation. There were no positive skin responses at the vehicle flanks and among the vehicle control group. 

There was no mortality, there were no remarkable clinical observations in any of the two groups. Body weights were not affected by treatment. 

 

According to the test results, CA 2219 A (Intermediate of CGA 276854) is required to be classified as ‘May cause sensitization by skin contact’ according to Commission Directive 93/21/EEC, issued May 4, 1993.