Benzene, C20-24 (even numbered) sec-alkyl derivs.

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

October 5, 1992-December 18, 1992

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Benzene, mono-C10-13-alkyl derivs., distn. residues

EC Number:

284-660-7

EC Name:

Benzene, mono-C10-13-alkyl derivs., distn. residues

Cas Number:

84961-70-6

IUPAC Name:

84961-70-6

Constituent 2

Reference substance name:

Benzene, mono-C10-13-alkyl derivs., distillation residues

IUPAC Name:

Benzene, mono-C10-13-alkyl derivs., distillation residues

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Fa. Dr. Karl Thomae GmbH, Biberach
- Age at study initiation: adult
- Weight at study initiation: 2-3 kg
- Housing: singly in stainless steel cages, identified by ear tags
- Diet (e.g. ad libitum): Ssniff K4, ad libitum
- Water (e.g. ad libitum): tap water, ad libitum
- Acclimation period: 14 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 +/- 3 degree C
- Humidity (%): 30-70%
- Air changes (per hr): 15 changes/hr
- Photoperiod (hrs dark / hrs light): 12 hrs light/12 hrs dark


IN-LIFE DATES: From: December 12, 1992 To: December 18, 1992

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Amount / concentration applied:

There was one intact skin test site per animal. Each test site was treated with 0.5 mL of undiluted test material.

Duration of treatment / exposure:

4 hrs

Observation period:

Observations for dermal irritation and defects occurred at 3/4, 24, 48, and 72 hours, and 6, 8, and 10 days after the occlusion period.

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: dorsal
- Type of wrap if used: Aesculap Favorita II


REMOVAL OF TEST SUBSTANCE
- Washing (if done): washed with warm water
- Time after start of exposure: 4 hrs


SCORING SYSTEM: Draize

Results and discussion

In vivo

Results

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24, 48, and 72 hrs

Score:

1.25

Irritant / corrosive response data:

All animals showed signs of erythema (maximum score of 2) by the 3/4 hr observation. Five of the six animals also showed edema (maximum score of 2) at that reading as well. Erythema and edema persisted through the 72 hr reading, though by the 6 day reading only 2 animals showed signs of erythema, and one animal still showed signs of edema. By the day 8 reading, all signs of erythema and edema had resolved. At the 72 hr observation, one animal display yellowish, and drying and cracking skin. At the 6 day observation, this animal, along with 3 others showed shedding skin. By the 8 day observation, most of these animals still showed shedding skin, though it was healing. By the 10 day observation, all symptoms had resolved.

Any other information on results incl. tables

Results of Skin Irritation Study

Animal	1	2	3	4	5	6
Erythema
¾ hr	2	1	2	1	2	2
24 hrs	2	2	1	2	2	1
48 hrs	2	2	1	1	2	1
72 hrs	3	2	1	2	3	1
6 days	2	0	0	0	1	0
8 days	0	0	0	0	0	0
10 days	0	0	0	0	0	0
Edema
¾ hr	1	1	2	1	1	0
24 hrs	1	1	1	1	1	0
48 hrs	1	1	0	1	1	0
72 hrs	2	1	0	1	1	0
6 days	1	0	0	0	0	0
8 days	0	0	0	0	0	0
10 days	0	0	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The primary irritation index was 1.25 and all symptoms were fully reversible within 14 days. The test substance is not classified as a skin irritant according to EU GHS guidelines.

Executive summary:

This study examined the potential of the test substance to cause irritation to skin. The test substance was placed on the skin of 6 male rabbits for 4 hrs, and covered with a semi-occlusive patch. After 4 hrs, the test substance was removed with warm water. The animals were scored for signs of edema and erythema according to the Draize scale at 3/4, 24, 48, and 72 hrs. Because symptoms were not fully resolved at the end of 72 hrs, the study was extended through 10 days after exposure. Signs of erythema (maximum score of 2) and edema (maximum score of 2) were seen at the 3/4 hr observation. These symptoms were fully resolved by the day 8 observation. Signs of discoloration, drying and cracking were seen starting at the 72 hr observation. By the day 10 observation, all of these symptoms were resolved as well. The primary irritation index was 1.25, and all symptoms were fully reversible. The test substance is therefore not classified as a skin irritant according to EU GHS guidelines.