Registration Dossier

Administrative data

Endpoint:
skin irritation / corrosion, other
Remarks:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1978
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: This study was performed pre-GLP. Alike OECD 404, but with some deviations.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1978
Report Date:
1978

Materials and methods

Test guidelineopen allclose all
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Qualifier:
according to
Guideline:
other: U.S. FDA (Fed. Reg. 28 (119), 5582, 1963)
Principles of method if other than guideline:
- exposure period 24 hours
- rabbit skin is exposed under occlusion
- the test substance is not moistened to ensure optimal skin contact
- the animal skin is exposed intact (6 animals) and abraded (6 animals)
- it cannot be assessed if/when effects are reversible. Observation were made up to 72 hour after exposure.
- no details on test animals and their accomodation
GLP compliance:
no
Remarks:
pre-GLP

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Test material form:
solid: crystalline
Details on test material:
Name: para toluenesulfonamide
Appearance: a white solid
Date received: 15 March 1978

No further data

Test animals

Species:
rabbit
Strain:
New Zealand White
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: no data
- Age at study initiation: no data
- Weight at study initiation: no data
- Housing: no data
- Diet (e.g. ad libitum): no data
- Water (e.g. ad libitum): no data
- Acclimation period: no data

ENVIRONMENTAL CONDITIONS
- Temperature (°C): no data
- Humidity (%): no data
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): no data

IN-LIFE DATES: no data

Test system

Type of coverage:
occlusive
Preparation of test site:
other: clipped
Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5g
Duration of treatment / exposure:
24 hours
Observation period:
The skin is evaluated 24 and 72 hours after the start of exposure.
Number of animals:
6 with intact and 6 with abraded skin
Details on study design:
TEST SITE
- Area of exposure: back of the animal
- % coverage: 2.5x2.5 cm
- Type of wrap if used: Surgical patch measuring 1 inch x 1 inch (2.5 x2.5 cm). The patches are fixed to the application site by means of adhesive tape and the entire trunk of the rabbits is wrapped with an impervious material.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): none
- Time after start of exposure: not applicable


SCORING SYSTEM: Draize
Erythema and eschar formation
0 No erythema
1 Very slight erythema (barely perceptible)
2 Well defined erythema
3 Moderate to severe erythema
4 Severe erythema (beet redness) to slight eschar formation (injuries in depth)

Oedema formation
0 No oedema
1 Very slight edema(barely perceptible)
2 Slight edema(edges of the area well defined by definite raising)
3 Moderate edema(raised approximately 1mm)
4 Severe edema( raised more than 1 mm and extending beyond the area of exposure)

Results and discussion

In vivo

Resultsopen allclose all
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 24-72 hours
Score:
0.3
Max. score:
4
Reversibility:
not fully reversible within: 72 hours
Remarks on result:
other: intact + abraded skin
Irritation parameter:
edema score
Basis:
mean
Time point:
other: 24-72 hours
Score:
0
Max. score:
4
Remarks on result:
other: intact + abraded skin
Irritant / corrosive response data:
after 24 hours: Highest score: very slight erythema, no oedema
after 72 hours: Highest score: very slight erythema, no oedema

No difference was observed between intact and abraded skin

Any other information on results incl. tables

Results

Rabbit No and sex

Hours after instillation

Average 24-72 hours:

Intact

Rabbit No and sex

Hours after instillation

Average 24-72 hours:

Abraded

Site

24

72

24

72

7247

erythema

1

0

0.5

7241

0

0

0

oedema

0

0

0

0

0

0

7248

erythema

D

D

D

7242

1

0

0.5

oedema

D

D

D

0

0

0

7249

erythema

0

0

0

7243

1

0

0.5

oedema

0

0

0

0

0

0

7250

erythema

0

0

0

7244

1

0

0.5

oedema

0

0

0

0

0

0

7251

erythema

1

0

0.5

7245

1

0

0.5

oedema

0

0

0

0

0

0

7252

erythema

0

1

0.5

7246

1

1

1

oedema

0

0

0

0

0

0

D = dead

Highest grade observed: very slight erythema, no oedema

Applicant's summary and conclusion

Interpretation of results:
not irritating
Remarks:
Migrated information Criteria used for interpretation of results: OECD GHS
Conclusions:
The results show that the test substance is very slightly irritating to skin. It causes minimal erythema and no oedema. The contact time is too long but the test substance was not moistened so contact with the skin may not have been optimal. Reversibility cannot be assessed but the effects are of such minimal nature that full reversibility is expected well within 14 days. Although this study has deviations performing a new study is not warranted because it will not provide any new information. With this study it has been shown that the substance is not a skin irritant according to GHS.
Executive summary:

The primary irritation of p-TSA to the skin is measured by a occlusive patch-test technique on the abraded and intact skin of albino rabbits. The study was performed according to methods similar to OECD404. but with the following deviations:

- exposure period 24 hours

- rabbit skin is exposed under occlusion

- the test substance is not moistened to ensure optimal skin contact

- the animal skin is exposed intact and abraded

- it cannot be assessed if/when effects are reversible. Observations were made up to 72 hour after exposure.

- no details on test substance identity or composition

- no details on test animals and their accommodation

Twelve healthy adult New Zealand White albino rabbits are used. Twenty four hours prior to applying the materials, the hair is removed from the backs of the animals with an electric clipper in such a way as to avoid abrasions. An amount of 0.5 g is placed on the skin under occlusion for 24 hours. The skin is evaluated 24 and 72 hours after the start of exposure. After 24 hours: very slight erythema after 72 hours: very slight erythema. No difference was observed between intact and abraded skin.

The results show that the test substance is very slightly irritating to skin. It causes minimal erythema (Very slight erythema - barely perceptible)

and no oedema. The contact time is too long but the test substance was not moistened so contact with the skin may not have been optimal. Reversibility cannot be assessed but the effects are of such minimal nature that full reversibility is expected well within 14 days. Although this study has many deviations performing a new study is not warranted because it is not expected to provide any new information. With this study it has been shown that the substance is not a skin irritant according to GHS.