Terephthalic acid

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

29 March to 29 June 1990

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Proprietary non-GLP study, conducted according to OECD guidelines

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1990

Report date:

1990

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

no

Remarks:

no certificate or statement of compliance included in report

Test material

Test material information

Constituent 1

Reference substance name:

Terephthalic acid

EC Number:

202-830-0

EC Name:

Terephthalic acid

Cas Number:

100-21-0

Molecular formula:

C8H6O4

IUPAC Name:

benzene-1,4-dicarboxylic acid

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

Terephthalic acid, identification no. 10820-97, described as a white powder and stored at room temperature (approximately 22°C).Purity not stated. However, terephthalic acid is a monomer used in the production of saturated polyesters, and a purified (> 99.9% w/w) feedstock (free of production-process impurities) is essential for this purpose. The batch of terephthalic acid used in this study is considered to have been representative of commercial production and to have been at least 99% pure.

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

The animals were New Zealand White rabbits of either sex, weighing approximately 2.0-3.5 kg on arrival. Rabbits were supplied by Johnson Rabbit Ranch, IN. The rabbits were acclimatised for at least 1 week prior to study initiation, during which time they were examined to ensure their health and suitability as test subjects,Each rabbit was housed individually in a suspended stainless steel cage. Poly pads were placed in the pans below the mesh.Approximately 150 g of Purina Lab Rabbit Chow HF #5326 (Ralston Purina Co., St. Louis, MO) was provided daily for each rabbit. Reverse osmosis purified water was available ad libitum.Individuals were identified by metal ear tags and corresponding cage cards. Fluorescent lighting was provided on a 12 hour light/dark cycle.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.5 g undiluted test material was applied (doses were weighed onto aluminium foil).

Duration of treatment / exposure:

4 hours

Observation period:

72 hours after dressing removal

Number of animals:

Three

Details on study design:

Prior to study initiation, the backs of all candidate test animals were shaved and checked for abnormalities. Animals found at this stage to have significant skin abnormalities encompassing the entire shaved back were not included in the study.Approximately 24 hours prior to testing, fur from the trunk of the animals was clipped so that no less than 10% (~240 cm²) of the dorsal body surface was available for application.The treated site was covered by a 2.5x2.5 cm adhesive dressing (Coverlet, Beiersdorf). The entire midsection of each rabbit was then wrapped in a lint free cloth towel secured by Elastoplast. Each rabbit had a treated and an untreated test site, to provide a control for comparison.All wrapping materials were removed 4 hours after application. Following unwrapping, the test sites were rinsed with approximately 2 ml of 0.9% saline and towel dried. All rabbits were weighed immediately prior to application of the test material. All animals were observed for morbidity and mortality at least once daily following treatment. All test sites were examined for signs of dermal irritation (oedema, erythema and/or eschar formation) and corrosivity (ulceration and/or necrosis) 30-60 minutes, 24, 48 and 72 hours after removal of the wrappings. The skin reactions were graded according to the Draize method (Draize, 1959).

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Remarks on result:

other: No data reported on individual animals

Results 2

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Remarks on result:

other: No data reported on individual animals

Results 3

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Remarks on result:

other: No data reported on individual animals

Results 4

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Remarks on result:

other: No data reported on individual animals

Results 5

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Remarks on result:

other: No data reported on individual animals

Results 6

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Remarks on result:

other: No data reported on individual animals

Results 7

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24, 48 and 72 hours

Score:

0.2

Reversibility:

fully reversible within: 72 hours

Irritant / corrosive response data:

No signs of dermal corrosivity were seen in any rabbit during the study. The irritation score ranged from 0.7/8.0 at 30-60 minutes, to 0.0/8.0 at 72 hours following unwrapping.

Other effects:

No other effects reported.

Any other information on results incl. tables

The irritation score ranged from 0.7/8.0 at 30-60 minutes, to 0.0/8.0 at 72 hours following unwrapping.

The Primary Dermal Irritation Score for terephthalic acid was 0.2.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated informationCriteria used for interpretation of results: EU

Conclusions:

The Primary Dermal Irritation Score for Terephthalic Acid was 0.2. No signs of dermal corrosivity were seen in any rabbit during the study.

Executive summary:

Terephthalic acid was applied for 4 hours to the shaved backs of three rabbits at a dose of 0.5 g. Following unwrapping, the test sites were rinsed with saline. All test sites were examined for signs of irritation and corrosivity according to the Draize method at 30 -60 minutes, 24, 48 and 72 hours following removal of the wrappings. No signs of dermal corrosivity were seen in any rabbit during the study. The irritation score ranged from 0.7/8.0 at 30-60 minutes, to 0.0/8.0 at 72 hours following unwrapping. The Primary Dermal Irritation Score for Terephthalic Acid was 0.2. It can be concluded that terephthalic acid is not irritating to rabbit skin.