Reaction products of 1-naphtylamino-5-sulfonic acid, 1,3-diaminobenzene and 4,4'-dinitrostilbene-2,2'-disulfonic acid, sodium salts

Endpoint summary

Description of key information

Skin irritation/corrosion: non irritant, non corrosive

Eye irritation/corrosion: non irritant, non corrosive

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:

key study

Study period:

September 1975

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study was performed not in GLP, according to the U.S federal guideline.

Qualifier:

according to guideline

Guideline:

other: "Hazardous Substances Regulations" under the U.S. Federal Hazardous Substances Labelling Act Sect. 191.11 (February 1965)

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
Strain: Porton
Age at study initiation: 9-13 weeks
Weight at study initiation: 2.36 Kgs. (males) and 2.55 Kgs (female)
Housing: maintained under a semi-barrier system. Caged singly in an experimental room
Diet: bred on the premises and maintained under a semi-barrier system. Commercial irradiated diet (Styles-Oxoid) was fed ad lib
Water: ad libitum, Sterile filtered
Acclimation period: acclimatized in the test area for one week prior to the start of the trial

ENVIRONMENTAL CONDITIONS
Temperature: 20 °C +/- 1°C
Humidity: 50-70 %
Photoperiod (hrs dark / hrs light): from 08.00 - 18.00 hours artificial light

Type of coverage:

occlusive

Preparation of test site:

abraded

Vehicle:

water

Controls:

yes, concurrent no treatment

Amount / concentration applied:

10 g of the test compound was mixed with 10 ml of water to make a solution of 15 ml 0.75 ml of which was applied to each test site on a 2.5 cm square gauze pad.

Duration of treatment / exposure:

72 hours

Observation period:

24,72 hours

Number of animals:

6 rabbits (3 males) (3 female)

Details on study design:

PREPARATION OF THE SKIN
Twenty-four hours prior to the dermal application, the backs of the rabbits were shaved over an area consisting of at least 10% of the total body surface. Two test sites lateral to the mid line of the back were used on each rabbit. Immediately before the application of the test compound, the right hand site was abraded with the point of a sterile hypodermic needle. The abrasions were sufficiently deep to penetrate the stratum corneum but not to damage the dermis. The left hand site remained intact.
COVER
After the application covered with aluminium foil secured with "Sleek"* adhesive tape. The test sites were then enclosed by a 6" wide "Coban" self
adhesive bandage the edges of which were fixed to the skin by strips of "Sleek" in order to retain the test substance in close contact with the skin.

Irritation parameter:

erythema score

Basis:

mean

Remarks:

all six animals

Time point:

72 h

Score:

0

Reversibility:

fully reversible within: 7 days

Remarks on result:

no indication of irritation

Remarks:

intact skin

Irritation parameter:

erythema score

Basis:

animal: two animals/6

Time point:

72 h

Score:

0.5

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: abraded skin

Irritation parameter:

erythema score

Basis:

animal: three animals/6

Time point:

72 h

Score:

1

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: abraded skin

Irritation parameter:

edema score

Basis:

animal #1

Time point:

72 h

Score:

0.5

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: intact skin

Irritation parameter:

edema score

Basis:

animal: tree animals/6

Time point:

72 h

Score:

1

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: intact skin

Irritation parameter:

edema score

Basis:

animal: two animals/6

Time point:

72 h

Score:

1.5

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: abraded skin

Irritation parameter:

edema score

Basis:

animal: four animals/6

Time point:

72 h

Score:

1

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: abraded skin

Irritant / corrosive response data:

A slight to well defined erythema was seen on 5/6 abraded sites and a very slight to moderate oedema on 4/6 intact and 6/6 abraded sites, 24 hours after application of the compound. At 72 hours very slight oedema was still present on one abraded site. The primary irritation score was 1.2.

Interpretation of results:

slightly irritating

Remarks:

Criteria used for interpretation of results: other: "Hazardous Substances Regulations" under the U.S. Federal Hazardous Substances Labelling Act Sect. 191.11 (February 1965)

Conclusions:

Slight primary skin irritant

Executive summary:

The test was carried out according to the method given in the "Hazardous Substances Regulations" under the U.S. Federal Hazardous

Substances Labelling Act Sect. 191.11 (February 1965).

To a prepared skin (intacted and abraded) of six rabbits (3 male, 3 female) 10 g of the test compound was mixed with 10 ml of water (to make a solution of 15 ml) 0.75 ml of which was applied to each test site on a 2.5 cm,, square gauze pad and covered.

Observation was done at 24 and 72 hours.

A slight to well defined erythema was seen on 5/6 abraded sites and a very slight to moderate oedema on 4/6 intact and 6/6 abraded sites, 24 hours after application of the compound. At 72 hours very slight oedema was still present on one abraded site. The primary irritation score was 1.2.

According to the method used the substance is a slight primary skin irritant in the albino rabbit.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Qualifier:

according to guideline

Guideline:

other: "Hazardous Substances Regulations" under the U.S. Federal Hazardous Substances Labelling Act Sect. 191.11 (February 1965

GLP compliance:

no

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
Strain: Porton
Age at study initiation: 9-13 weeks
Weight at study initiation: 2.36 Kgs. (males) and 2.55 Kgs (female)
Housing: maintained under a semi-barrier system. Caged singly in an experimental room
Diet: bred on the premises and maintained under a semi-barrier system. Commercial irradiated diet (Styles-Oxoid) was fed ad lib
Water: ad libitum, Sterile filtered
Acclimation period: acclimatized in the test area for one week prior to the start of the trial

ENVIRONMENTAL CONDITIONS
Temperature: 20 °C +/- 1°C
Humidity: 50-70 %
Photoperiod (hrs dark / hrs light): from 08.00 - 18.00 hours artificial light

Vehicle:

water

Controls:

yes, concurrent no treatment

Amount / concentration applied:

100 mg

Duration of treatment / exposure:

The rabbits were examined 1, 24, 48 and 72 hours after application of the test compound and for any further period that was considered necessary.

Observation period (in vivo):

The eyes of the experimental animals were examined and found normal prior to the test.
14 days

Number of animals or in vitro replicates:

6 rabbits (3 male, 3 female)

Details on study design:

The test compound were instilled into the conjunctival sac of the left eye. The eyelids were then held closed for 1 second. After 30 seconds the compound was, as far as possible, flushed out of the eyes- of three of the rabbits with warm water for 1 minute.

Irritation parameter:

cornea opacity score

Basis:

animal:

Remarks:

all of six animals

Time point:

24/48/72 h

Score:

0

Reversibility:

fully reversible within: 14 days

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal: all of the six animals

Time point:

24/48/72 h

Score:

0

Reversibility:

fully reversible within: 14 days

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal: six animals/6

Time point:

24 h

Score:

1

Reversibility:

fully reversible within: 14 days

Irritation parameter:

conjunctivae score

Basis:

animal: one animal/6

Time point:

48 h

Score:

0.17

Reversibility:

fully reversible within: 14 days

Irritation parameter:

conjunctivae score

Basis:

animal: all otf the six animals

Time point:

72 h

Score:

0

Irritation parameter:

chemosis score

Basis:

animal: two anilmals/6

Time point:

24 h

Score:

0.83

Reversibility:

fully reversible within: 14 days

Irritation parameter:

chemosis score

Basis:

animal: one animals/6

Time point:

48 h

Score:

0

Irritation parameter:

chemosis score

Basis:

animal: six animals

Time point:

72 h

Score:

0

Irritant / corrosive response data:

A very slight to mild conjunctival reaction was seen in all treated eyes one hour after application of the compound. These reactions subsided slowly over the subsequent days until all had returned to normal by 48 hours (1/3 washed eyes), 6 days (2/3 washed eyes), 10 days (2/3 unwashed eyes) and 14 days (l/3 unwashed eyes). Staining of the conjunctivae by the compound was seen in all three unwashed eyes for up to 72 hours. Transient damage to the surface epithelium of the cornea was seen at one hour only in one rabbit (No.12).

Interpretation of results:

other: minimal eye irritant

Remarks:

Criteria: Drugs and Cosmetics" page 51, published by the Association of Food and Drug Officials of the U.S.A.

Conclusions:

minimal eye irritant in the albino rabbit

Executive summary:

The test was carried out according to the method given in the "Hazardous Substances Regulations" under the U.S. Federal Hazardous

Substances Labelling Act Sect. 191.11 (February 1965).

In to the left eye of six rabbits (3 male, 3 female) 100 g of the test compound was instilled into the conjunctival sac. The eyelids were then held closed for 1 second. After 30 seconds the compound was, as far as possible, flushed out of the eyes of three of the rabbits with warm water for 1 minute.

Observation was done at 24 and 72 hours and 14 days.

A very slight to mild conjunctival reaction was seen in all treated eyes one hour after application of the compound. These reactions subsided slowly over the subsequent days until all had returned to normal by 48 hours (1/3 washed eyes), 6 days (2/3 washed eyes), 10 days (2/3 unwashed eyes) and 14 days (1/3 unwashed eyes). Staining of the conjunctivae by the compound was seen in all three unwashed eyes for up to 72 hours. Transient damage to the surface epithelium of the cornea was seen at one hour only in one rabbit (No.12).

The substance is considere minimal eye irritant in the albino rabbit.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation/corrosion

The test was carried out on the registered substance according to the method given in the “Hazardous Substances Regulations” under the U.S. Federal Hazardous Substances Labelling Act Sect. 191.11 (February 1965).

A slight to well defined erythema was seen on 5/6 abraded sites and a very slight to moderate oedema on 4/6 intact and 6/6 abraded sites, 24 hours after application of the compound. At 72 hours very slight oedema was still present on one abraded site. The primary irritation score was 1.2. According to the method used and the FDA classification criteria the substance is a slight primary skin irritant in the albino rabbit. However, the substance is considered not irritant for the skin according to theCLP Regulation 1272/2008/EC based on the evaluation of the detailed scores.

For skin irritation/corrosion there are studies available on similar substances. The Similar substance 01 was applied to intact and abraded skin of 6 rabbits. In the intact skin the mean reaction score was 0.7 (24h) and in the abraded skin the value was 2.7 (24h). The effects are reversible and after 8 days there were reduced to mean reaction score 0 (intact skin) and to 0.6 (abraded skin). The substance was classified as moderately irritant according to the USA/FDA criteria.

The similar substance 02 didn’t show irritating properties when applied to skin of rabbits. This result of this study supports the classification as non-irritant.

Eye irritation/corrosion

The test was carried out on the registered substance according to the method given in the “Hazardous Substances Regulations” under the U.S. Federal Hazardous Substances Labelling Act Sect. 191.11 (February 1965).

A very slight to mild conjunctival reaction was seen in all treated eyes one hour after application of the compound. These reactions subsided slowly over the subsequent days until all had returned to normal by 48 hours (1/3 washed eyes), 6 days (2/3 washed eyes), 10 days (2/3 unwashed eyes) and 14 days (1/3 unwashed eyes). Staining of the conjunctivae by the compound was seen in all three unwashed eyes for up to 72 hours. Transient damage to the surface epithelium of the cornea was seen at one hour only in one rabbit (No.12).

The substance is considered minimal eye irritant in the albino rabbit.

For eye irritation determination there are two studies available on similar substances. The study on Similar substance 01 was done according to OECD405 and is GLP compliant and no irritation effects were noted. The study on Similar substance 02 showed that the substance gave a certain effect irritation after application of the substance to eyes of rabbits, but the effects are fully reversible after 14 days. In addition, QSAR prediction was done on the registered substance (as constituent 1) and the outcome of QSAR dyes R&C version 5.2, EYE IRRITATION MODEL (2018) is that there is no potential for eye damage and eye irritation.

Based on the results the conclusion is that the substance is considered as non-irritant to eyes.

Justification for classification or non-classification

Skin irritation

Substances that have the potential to induce reversible skin irritation are classified in Category 2 (irritating to skin).

According to the CLP Regulation 1272/2008/EC, the substance can be classify as a single irritant category (Category 2) according to the criteria, section 3.2, table 3.2.2.

If, when applied to the skin of an animal, the substance produces:

(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; or

(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.

Reversibility of skin lesions is the other decisive factor in evaluating responses in the animal test.

During the test a slight to well defined erythema was seen on 5/6 abraded sites and a very slight to moderate oedema on 4/6 intact and 6/6 abraded sites, 24 hours after application of the compound. At 72 hours very slight oedema was still present on one abraded site.

According to the USA Federal Hazardous Substances Act (US-FHSA) the substance is considered slight irritant to the skin.

Studies performed according to the USA Federal Hazardous Substances Act (US-FHSA) may be used for classification purposes although they deviate in their study protocol from the OECD TG 404. They do not include a 48-hour observation time and involve a 24-hour test material exposure followed by observations at 24 hour and 72 hours. Moreover, the test material is patched both on abraded and on intact skin of six rabbits. Studies usually are terminated after 72 hours. In case of no or minimal responses persisting until the 72 hours time points it is feasible to use such data for classification by calculating the mean values for erythema and oedema on the basis of only the 24 and 72 hours time points. Calculation of mean scores should normally be restricted to the results obtained from intact skin. In case of pronounced responses at the 72 hours time point an expert judgement is needed as to whether the data is appropriate for classification. In addition, the test that has been conducted with more than three animals. In this case, the Category 2 is assigned if 4 of 6 rabbits show a mean score of 2.3 or above. Taking in consideration those information, evaluation has been made based on the average score per animal using the results of the original studies.

Any of the animals has reached the cut-off value of 2.3 and the calculation of the scores based on the CLP Regulation criteria.

In addition, Similar substance 01 test confirm this non classification.

Therefore, according to the paragraph 3.2. of the CLP Regulation n. 1272/2008, the substance is not classified as a skin irritant/skin corrosive.

As conclusion, no classification is warranted with regard to skin irritation according to CLP Regulation.

Eye irritation

Substances that have the potential to induce reversible eye irritation are classified in Category 2 (irritating to eyes).

According to the CLP Regulation 1272/2008/EC, using the results of animal testing the substance can be classify as a single irritant category (Category 2) according to the criteria, section 3.3, table3.3.2.

If, when applied to the eye of an animal, the substance produces:

– at least in 2 of 3 tested animals, a positive response of:

– corneal opacity ≥ 1 and/or

– iritis ≥ 1, and/or

– conjunctival redness ≥ 2 and/or

– conjunctival oedema (chemosis) ≥ 2

calculated as the mean scores following grading at 24, 48 and 72 hours after installation of the test material, and which fully reverses within an observation period of 21 days.

A very slight to mild conjunctival reaction was seen in all treated eyes one hour after application of the compound. These reactions subsided slowly over the subsequent days until all had returned to normal by 48 hours (1/3 washed eyes), 6 days (2/3 washed eyes), 10 days (2/3 unwashed eyes) and 14 days (1/3 unwashed eyes). Staining of the conjunctivae by the compound was seen in all three unwashed eyes for up to 72 hours. Transient damage to the surface epithelium of the cornea was seen at one hour only in one rabbit.

According to the USA Federal Hazardous Substances Act (US-FHSA) the substance is considered minimal irritant to the eye.

The test that has been conducted with more than three animals.

Classification as eye irritation – Category 2 if at least 4 out of 6 rabbits show a mean score (24, 48 and 72 hours):

1 for the cornea and/or

1 for the iris and/or

2 conjunctival erythema and/or

2 conjunctival swelling

Observation at 24, 48 and 72 hours are recored on Conjuntivae redness and chemosis, where the calculated means are less than 2.

Test on similar substances revealed effects on eyes but out of the CLP criteria.

As conclusion, according to the paragraph 3.3. of the CLP Regulation n. 1272/2008, no classification is warranted with regard to the eye irritation.