Disodium phthalate

Skin irritation / corrosion

Administrative data

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 23 October 2012 to 02 November 2012.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline and EU method. GLP study.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2013

Report date:

2013

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Disodium phthalate

EC Number:

240-106-6

EC Name:

Disodium phthalate

Cas Number:

15968-01-1

Molecular formula:

C8H6O4.2Na

IUPAC Name:

disodium phthalate

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): Phthalic acid sodium salt (disodium phthalate)
- Physical state: white powder
- Analytical purity: > 95%
- Storage condition of test material: room temperature in the dark

Test animals

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Harlan Laboratories UK Ltd., Leicestershire, UK.
- Age at study initiation: twelve to twenty weeks old.
- Weight at study initiation: 2.27 or 2.51 kg.
- Housing: The animals were individually housed in suspended cages.
- Diet (e.g. ad libitum): 2930C Teklad Global Rabbit diet, ad libitum.
- Water (e.g. ad libitum): drinking water, ad libitum.
- Acclimation period: At least five days.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17 to 23°C
- Humidity (%): 30-70%
- Air changes (per hr): at least fifteen changes per hour.
- Photoperiod (hrs dark / hrs light): twelve hours continuous light (06:00 to 18:00) and twelve hours darkness.

Test system

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

other: moistened sufficiently with 0.5 ml of distilled water to achieve a paste

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): At each test site a quantity of 0.5 g of the test item.

Duration of treatment / exposure:

4 hours

Observation period:

1, 24, 48 and 72 hours

Number of animals:

Two males.

Details on study design:

TEST SITE
- Area of exposure: 2.5 x 2.5 cm
- Type of wrap if used: Each cotton gauze patch was secured in position with a strip of surgical adhesive tape. To prevent the animal interfering with the patches, the trunk of the rabbit was wrapped in an elasticated corset for the duration of the exposure period.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Any residual test item was removed by gentle swabbing with cotton wool soaked in distilled water.
- Time after start of exposure: 4 hours

SCORING SYSTEM:
Erythema and Eschar Formation Value
No erythema .............................................................................................................. ............... 0
Very slight erythema (barely perceptible) ..............................................................................1
Well-defined erythema ............................................................................................................. 2
Moderate to severe erythema ................................................................................................. 3
Severe erythema (beef redness) to eschar formation preventing grading of erythema 4

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

Any other skin reactions and clinical signs of toxicity, if present, were also recorded.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: 24-72 h

Score:

0

Results 2

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: 24-72 h

Score:

0

Results 3

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: 24-72 h

Score:

0

Results 4

Irritation parameter:

edema score

Basis:

animal #2

Time point:

other: 24-72 h

Score:

0

Irritant / corrosive response data:

No evidence of skin irritation was noted during the study.

Other effects:

Both animals showed expected gain in bodyweight during the study.

Any other information on results incl. tables

Table 2 Individual Skin Reactions Following 4-Hour Exposure

Skin Reaction	Observation Time (following patch removal)	Individual Scores – Rabbit Number and Sex		Total
		72599 Male	72631 Male
Erythema/Eschar Formation	Immediately	0	0	( 0 )
	1 Hour	0	0	( 0 )
	24 Hours	0	0	0
	48 Hours	0	0	( 0 )
	72 Hours	0	0	0
Oedema Formation	Immediately	0	0	( 0 )
	1 Hour	0	0	( 0 )
	24 Hours	0	0	0
	48 Hours	0	0	( 0 )
	72 Hours	0	0	0

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test item produced a primary irritation index of 0.0 and was classified as non-irritant to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.

Executive summary:

The study was performed to assess the irritancy potential of the test item to the skin of the New Zealand White rabbit. The method was designed to be compatible with OECD Guideline No. 404 “Acute Dermal Irritation/Corrosion” and Method B4 Acute Toxicity (Skin Irritation) of Commission Regulation (EC) No. 440/2008. 3-minute and 1-hour semi-occluded applications of the test item to the intact

skin of one rabbit produced no evidence of skin irritation. A single 4-hour, semi-occluded application of the test item to the intact skin of two rabbits produced no evidence of skin irritation. The test item produced a primary irritation index of 0.0 and was classified

as non-irritant to rabbit skin according to the Draize classification scheme. No corrosive effects were noted.