Benzenebutanoic acid, 4-chloro-.beta.-methyl-3-nitro-.gamma.-oxo-

Endpoint summary

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

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

EU Method B.6 (Skin Sensitisation)

GLP compliance:

yes

Type of study:

guinea pig maximisation test

Species:

guinea pig

Strain:

Dunkin-Hartley

Sex:

female

Details on test animals and environmental conditions:

TEST ANIMALS
- Source: charles River Deutschland, Kissleg, Germany
- Age at study initiation: Young adult animals (approx 4 weeks old)
A controlled environment was mantained in the room with optimal conditions considered as being approximately 15 air changes per hour, a temperature of 21 ± 3 º C, a relative humidity of 30-70 % and 12 hours artificial fluoerescent light and 12 hours dark per day
Temporary deviations of a maximum of 205 on relativie humidity occur and might have been caused by cleaning procedures, based on historical data these deviations were considered not to affect the tudy integrity.

Group housing of 5 animals per labelled metal cage with wire-mesh floors. The acclimatisatiobn period was at least 5 days before the start of treatment under laboratory conditions.

Free acces to standard guinea pig diet, including ascorbic acid (1000mg/Kg). Free acces to tap water .

Route:

intradermal and epicutaneous

Vehicle:

propylene glycol

Concentration / amount:

20 % for intradermal induction and 50 % for epidermal induction and a 10 % test substance concentration for challenge phase

Route:

intradermal and epicutaneous

Vehicle:

propylene glycol

Concentration / amount:

20 % for intradermal induction and 50 % for epidermal induction and a 10 % test substance concentration for challenge phase

No. of animals per dose:

10 animals and 5 animals for control

Details on study design:

Preliminary irritation study performed . Based on the results the test substance concentrations were 20 % for intradermal induction and 50 % for epidermal induction and a 10 % test substance concentration for challenge phase
INDUCTION on experimental and control animals was exactly the same except that vehicle alone was administered for control
Challenge is performed on all animals
INDuction description:
day 1 intradermal injections
day 3 asessment of irritation
day 8 patch application

Challenge controls:

CHALLENGE
day 22 epidermal application
dressing removed at 24 h and assesment for challenge reactions 24 h and 48 h after dressing removal.

Positive control substance(s):

yes

Remarks:

alfa hexylcinnamicaldehyde

Reading:

rechallenge

Hours after challenge:

24

Group:

test chemical

Dose level:

10%

No. with + reactions:

10

Total no. in group:

10

Remarks on result:

other: Reading: rechallenge. . Hours after challenge: 24.0. Group: test group. Dose level: 10%. No with. + reactions: 10.0. Total no. in groups: 10.0.

TABLE 1 INDUCTION READINGS

Animal number	intradermal injection (observation day 3)						epidermal exposure (day 10)
	A		B		C		D
Control	E	N	E	N	E	N	Erythema(grade)	Oedema (mm diameter)
546	3			4		4	0	0
547	4			4		4	0	0
548	3			5		5	2	0
549	3			4		3	0	0
550	3			4		3	0	0
Experimental	E	N	E	N	E	N
551	4			4		3	2t	0
552	3			7		3	2t	0
553	3			5		2	2t	0
554	4			5		4	2t	0
555	4			4		2	2t	0
556	4			6		4	2t	0
557	4			7		5	2t	0
558	3			5		3	2t	0
559	3			5		2	2t	0
560	3			5		2	3t	0

A: 1:1 Mixture of FCA (Freunds adjuvamt)and water fro injection

B. 20% test substanceconcentratuion (Experimental); vehicle (control)

C: 1:1 Mixture of FCA and a 20% conentration (experimental) or vehicle (Control)

D: A 50 % test substance concentration (experimental) , vehicle (contyrol)

t : yellow staining of the skin by the test substance

TABLE 2 CHALLENGE READINGS

Animal number	Day 24 / Day 25
	10 % (mg/L)	Vehicle	10 % (mg/L)	Vehicle	comments
546	0	0	0	0
547	0	0	0	0
548	0	0	0	0
549	0	0	0	0
550	0	0	0	0
experimental
551	2	0	1	0	sensitised
552	2	0	2	0	sensitised
553	3	0	2k	0	sensitised
554	2	0	2k	0	sensitised
555	2	0	2	0	sensitised
556	2	0	1	0	sensitised
557	2	0	2p	0	sensitised
558	2	0	2k	0	sensitised
559	3k	0	3k	0	sensitised
560	3	0	2	0	sensitised

k.Scabs, p. Scaliness

Interpretation of results:

sensitising

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The skin reactions observed in response to a 10 % test substance concentration in ten (of the ten) experimental animals in the challenge phase were considered indicative of sensitisation, based on the absence of any response in the control animals. This results indicate a sensitisation of 100 %

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (sensitising)

Additional information:

Migrated from Short description of key information:
Based on the results and according EC criteria GAMMANAP STEP 5 should be labelled as causant of sensitisation (R43/H317)

Justification for selection of skin sensitisation endpoint:
Only available study

Justification for classification or non-classification

The skin reactions observed in response to a 10 % test substance concentration in ten (of ten) experimental animals in the challenge phase were considered indicative of sensitisation, based on the absence of any response in the control animals. These results indicated a sensitisation rate of 100 %

Based on the results and according EC criteria GAMMANAP STEP 5 should be calssified as causant of sensitisation (R43/H317)