Chromium, 3-hydroxy-4-[(2-hydroxy-1-naphthalenyl)azo]-7-nitro-1-naphthalenesulfonic acid complex

Endpoint summary

Description of key information

skin irritation, OECD 404, intact and scarified skin of rabbits, not irritating

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:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: Study following official guideline non GLP compliant. The value at 48h is missing. For the calculation of edema mean score the worse value recorded between 24 and 72h is considered.

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Source: Breeding Farm VELAZ
Acclimatisation: minimum 5 days
Total number: 3 healthy adult animals
Housing: individually caged withotu bedding in conventional animal room
Diet: pelleted standard diet (Velaz)
Water: dringking tap water ad libitum
Microclimatic conditions: room temperature 17-23°C permanently monitored
Relative humidity: 30-70% permanently monitored
light: 12 hours light/dark cycle
Identification of animals: code number on inner side of ear of animal, number of study on each cage
Health condition: certificate of good heltah condition-from breeding farm; no sogns of diseases were observed at clinical check-in, in acclimatisation period and before the start of experiment

Type of coverage:

semiocclusive

Preparation of test site:

other: intact and scarified

Vehicle:

other: moistened with water

Amount / concentration applied:

0.5g

Duration of treatment / exposure:

4 hours

Observation period:

1,24,48 and 72h

Number of animals:

3

Details on study design:

Approximately 24 hours before application the fur on the dorsal area of the trunk was removed by close-clipping (area- 6 x 6). Only animals with healthy intact skin were used. The same area was prepared for test with scarification-the skin lesions were prepared by incisions in stratum corneum.
The test item was used in delivered form. The test item was applied on intact skin (and on scarified skin) and then it was covered by gauze patch, foil and cellulose cotton and held in place with non-irritating tape - Spofaplast (semi-occlusive dressing). At the end of each exposure period the patch was removed and remaining sample was washed with water.

Clinical observation of the animals was carried out before application and daily during the study.

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #1

Time point:

24 h

Score:

ca. 3

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #1

Time point:

48 h

Score:

ca. 3

Reversibility:

no data

Remarks on result:

other: the value at 48h is missing in the original report. Worst result between 24 and 72h is supposed and used in the mean score value

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #1

Time point:

72 h

Score:

ca. 0

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #2

Time point:

24 h

Score:

ca. 4

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #2

Time point:

48 h

Score:

ca. 4

Reversibility:

no data

Remarks on result:

other: the value at 48h is missing in the original report. Worst result between 24 and 72h is supposed and used in the mean score value

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #2

Time point:

72 h

Score:

ca. 0

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #3

Time point:

24 h

Score:

ca. 2

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #3

Time point:

48 h

Score:

ca. 2

Reversibility:

no data

Remarks on result:

other: the value at 48h is missing in the original report. Worst result between 24 and 72h is supposed and used in the mean score value

Irritation parameter:

edema score

Remarks:

intact skin

Basis:

animal #3

Time point:

72 h

Score:

ca. 0

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #4

Time point:

24 h

Score:

ca. 3

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #4

Time point:

48 h

Score:

ca. 3

Reversibility:

no data

Remarks on result:

other: the value at 48h is missing in the original report. Worst result between 24 and 72h is supposed and used in the mean score value

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #4

Time point:

72 h

Score:

ca. 2

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #5

Time point:

24 h

Score:

ca. 4

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #5

Time point:

48 h

Score:

ca. 4

Reversibility:

no data

Remarks on result:

other: the value at 48h is missing in the original report. Worst result between 24 and 72h is supposed and used in the mean score value

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #5

Time point:

72 h

Score:

ca. 3

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #6

Time point:

24 h

Score:

ca. 2

Reversibility:

no data

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #6

Time point:

48 h

Score:

ca. 2

Reversibility:

no data

Remarks on result:

other: the value at 48h is missing in the original report. Worst result between 24 and 72h is supposed and used in the mean score value

Irritation parameter:

edema score

Remarks:

scarified skin

Basis:

animal #6

Time point:

72 h

Score:

ca. 0

Reversibility:

no data

Irritant / corrosive response data:

intact skin edema mean score animal # 1= 2
intact skin edema mean score animal # 2 = 2.6
intact skin edema mean score animal # 3 = 1.3
scarified skin edema mean score animal # 4 = 2.6
scarified skin edema mean score animal # 5 = 3.6
scarified skin edema mean score animal # 6 = 1.3

Erythema scores were recorded only at 72h due to skin discolouration, and therefore are not used in the irritative response assessment.

Other effects:

There was no evidence of a corrosive effect on the skin. No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occured

Interpretation of results:

other: not classified under Regulation 1272/2008

Conclusions:

The substance was tested for skin irritation following OECD 404. Under the experimental conditions did not show any skin irritation properties.

Executive summary:

The test substance was tested in the study for acute dermal irritation/corrosion. Rabbits (New Zealand Albino breed) were used for the test.

 Test was performed according to method OECD Guideline for Testing of Chemicals No. 404 - Acute Dermal Irritation/Corrosion, Adopted 12 May 1981, with internal procedure modification. Three rabbits were exposed to 0.5 g of the test sample, applied onto clipped skin for 4 hours using a semi-occlusive dressing. Skin reactions were evaluated after patch removal and observations were made 1, 24, and 72 hours after exposure.            

The evaluation of erythema was not possible, because the test substance caused coloration of skin. Moderate or severe oedema was observed in animals after 24 hours. 72 hours after patch removal only very slight erythema in two animals was observed. Moderate, slight or very slight oedema on scarified skin was observed in animals.

 

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

A study on skin irritation (Synthesia, 1988) on abraded and intact skin of albino rabbits is available where only oedema effect was recoreded (erythema was not possible due to discolouration of the skin). The value at 48h is missing and the worst grade between 24 and 72h was used instead. 2 out of 3 animals showed edema irritation parameter < 2.3 adn therefore the substance is not considered a skin irritant.

Justification for classification or non-classification

According to the CLP Regulation (EC n. 1272/2008) the following classifications apply:

 

Skin irritant cat2:

1) Mean value of ≥ 2,3 - ≤ 4,0 for erythema/ eschar or for oedema in at least 2 of 3 tested animals from gradings at 24, 48 and 72 hours after patch removal or, if reactions are delayed, from grades on 3 consecutive days after the onset of skin reactions; or

2)Inflammation that persists to the end of the observation period normally 14 days in at least 2 animals, particularly taking into account alopecia (limited area), hyperkeratosis, hyperplasia, and scaling; o

3) In some cases where there is pronounced variability of response among animals, with very definite positive effects related to chemical exposure in a single animal but less than the criteria above.

Based on the results of the skin irritation test, the substance is not classified for skin irritation properties