1,3-dichlorobenzene

Endpoint summary

Description of key information

OECD TG 404 (Schreiber G):Skin Irritant Category 2

OECD TG 405 (Bayer AG): Not classified


The in vivo skin irritation/corrosion study conducted was sufficient to classify the test item to be irritating to the skin with a category 2 classification according to CLP Regulation (EC) No 1272/2008.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable well documented report which meets basic scientific principles

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

no

Remarks:

GLP was not mandatory at the time of the study

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: W. Ostrop, Meerbusch, Germany

- Weight at study initiation: 3.1 kg
- Housing: animals were housed in a single cage
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 7-14 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 16-18°C
- Humidity (%): 40%
- Photoperiod (hrs dark / hrs light): 12hrs dark/ 12hrs light

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

other: alcool

Controls:

other: not applicable

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 500µL

Duration of treatment / exposure:

24 hours

Observation period:

8 days

Number of animals:

6

Details on study design:

The skin of the flank of 6 rabbits was depilated with an electric hair cutting machine 24 hours before the start of the test on both sides of the body in an area of approximately 8x8 cm. The skin of the right flank on the treatment area was additionally scarified with a scarificator.
A 2.5 x 2.5 cm Patch made of double layers surgery gauze was filled / soaked with 500µL of the liquid test substance and covered with an indifferent, impermeable PVC-foil.

The PVC-foil together with the underlying Patch was fixed with adhesive strip (Leukoflex®) at two treatment sites. Subsequently, the entire body of the animals was wrapped for the duration of the exposure time of 24 h with elastic with a binder (Eloflex®). The animals were immobilized.



SCORING SYSTEM: Draize score

Irritation parameter:

erythema score

Basis:

mean

Remarks:

of 6 animals

Time point:

24/48/72 h

Score:

0.8

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

edema score

Basis:

mean

Remarks:

of 6 animals

Time point:

24/48/72 h

Score:

2.7

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

other: erythema score abraded skin

Basis:

mean

Remarks:

of 6 animals

Time point:

other: 24, 48, 72 hours

Score:

0.8

Max. score:

4

Reversibility:

not reversible

Irritation parameter:

other: edema score abraded skin

Basis:

mean

Remarks:

of 6 animals

Time point:

other: 24, 48, 72 hours

Score:

3

Max. score:

4

Reversibility:

not reversible

Readingsintactskin  Animal  Erythema  Edema  24 h  1  0  4  24 h  2  0  3  24 h  3  0  3  24 h  4  0  3  24 h  5  0  3  24 h  6  0  3  48 h  1  0  4  48 h  2  0  3  48 h  3  0  3  48 h  4  0  3  48 h  5  0  3  48 h  6  0  3  72 h  1  2  3  72 h  2  2  2  72 h  3  2  1  72 h  4  3  1  72 h  5  3  2  72 h  6  3  1  Mean24 -72h  1 0.7  3.7   Mean 24 -72h  2 0.7 2.7   Mean 24 -72h  3 0.7 2.3  Mean 24 -72h  4 1 2.3  Mean 24 -72h  5 1 2.7  Mean 24 -72h  6 1 2.3 Total mean   0.85  2.7

 

 

Readingsabradedskin	Animal	Erythema	Edema
24 h	1	0	4
24 h	2	0	4
24 h	3	0	3
24 h	4	0	3
24 h	5	2	3
24 h	6	0	3
48 h	1	0	4
48 h	2	0	3
48 h	3	0	3
48 h	4	0	3
48 h	5	2	3
48 h	6	0	3
72 h	1	2	4
72 h	2	2	3
72 h	3	2	3
72 h	4	2	1
72 h	5	3	2
72 h	6	3	1
Mean24 -72h	1	0.7	4
Mean 24 -72h	2	0.7	3.7
Mean 24 -72h	3	0.7	3
Mean 24 -72h	4	0.7	2.3
Mean 24 -72h	5	1	2.7
Mean 24 -72h	6	1	2.3
Total mean		0.8	3

 

Interpretation of results:

Category 2 (irritant) based on GHS criteria

Conclusions:

Under the conditions of this study, the test item is irritating to the skin and a Category 2 skin irritant according to CLP Regulation (EC) No. 1272/2008.

Executive summary:

The primary irritant/corrosive effect of pure 1,3-dichlorobenzene, has been tested on rabbit skin with a Patch Test.

5 New Zealand White rabbits have been tested with 500µL of 1,3-dichlorobenzene for 24 hours followed by expsoure period of 8 days.

The evaluation of the skin demages was performed according to Draize.

Mean scores over 24, 48, and 72 hours for each animal were 2.7 for edema and 0.8 for erythema for intact skin, and 3 for edema and 0.8 for edema for abraded skin.

According to the CLP Regulation (EC) No. 1272/2008 the test substance was classified as a Category 2 skin irritant.  

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

In the key-study for skin irritation/corrosion, 5 New Zealand White rabbits have been tested with 500µl of 1,3-dichlorobenzene for 24 hours followed by exposure period of 8 days. The evaluation of the skin damages was performed according to Draize.

Mean scores over 24, 48, and 72 hours for each animal were 2.7 for edema and 0.8 for erythema for intact skin, and 3 for edema and 0.8 for edema for abraded skin.

In the key-study for eye irritation, 100 µl test compound was instilled into the conjunctival sac of one eye of each of 6 rabbits. The lids were then gently held together for about one second. The other eye remained untreated and served as control. The treated eye was not washed after instillation of the test compound. The irritation scores / mean irritation scores were calculated for cornea, iris, erythema and swelling (chemosis) of the conjunctivae were calculated according to Draize at 24, 48 and 72 hours.

A cornea score = 0.22, an iris score = 0 was determined. The conjunctiva score was = 0.6 and the chemosis was = 0.4. Irritating effects were still observable during the 8-day observation period only in 1/6 animal (redness) and 2/6 animals (chemosis). Therefore 1,3-dichlorobenzene was considered as not eye irritating.

Justification for selection of skin irritation / corrosion endpoint:
The most reliable study was used as key study and for classification.

Justification for selection of eye irritation endpoint:
The most reliable study was used as key study and for classification.

Effects on skin irritation/corrosion: irritating

Justification for classification or non-classification

1,3-dichlorobenzene was irritating to the skin. According to EU-GHS regulations a classification as Skin Irrit.Cat 2, H315 (causes skin irritation) is justified.

The test substance was slightly irritating to the eye, but the measured score values were not sufficient for classification.