Benzenesulfonic acid, 2-[(2Z)-2-(2,6-diamino-4-oxo-5(4H)-pyrimidinylidene)hydrazinyl]-3-methyl-

Endpoint summary

Description of key information

The substance  was found to be non irritating in the in-vivo study for skin and eye irritation (OECD 404 and 405) and in the in-vitro EPISKIN test for skin irritation (EU B.46) (BSL 2009b and c, Bioassay 2013).

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:

2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

Version of April 24, 2002

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

0.5g

Duration of treatment / exposure:

single treatment

Observation period:

14 days

Number of animals:

3

Details on study design:

The cutaneous reactions were assessed immediately after removal of the patch, approximately 1, 24, 48 and 72 hours after removal of the patch and in weekly intervals until day 14.

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Reversibility:

not fully reversible within: 14 days

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Reversibility:

fully reversible within: 7 days

Irritation parameter:

edema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Irritation parameter:

edema score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Irritation parameter:

edema score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

The following test item-related clinical observations were recorded during the course of

the study:

· Very slight to well-defined erythema (grade 1-2)

The cutaneous reactions were reversible in one animal within 72 hours and in another animal within 7 days after removal of the patch. In the third animal very slight erythema was still observed on day 14 (study termination).

Mean scores over 24, 48 and 72 hours for each animal were 0.0, 2.0 and 1.0 for erythema and 0.0, 0.0 and 0.0 for edema.

Interpretation of results:

GHS criteria not met

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

Study period:

2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study, guideline compliant

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

Species: Healthy New Zealand White Rabbits
Strain: Crl:KBL (NZW)
Source: Charles River Deutschland, D-88353 Kisslegg
Sex: female
Body weight at the beginning of the study: 4.5, 4.5, 3.9 kg
Age at the beginning of the study: approximately 13 weeks old
Number of animals: 3
The animals were derived from a controlled full barrier maintained breeding system (SPF). According to Art. 9.2, No.7 of the German Act on Animal Welfare the animals were bred for experimental purposes.

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

A dose of 0.1 g of the test item was applied to the test site.

Duration of treatment / exposure:

The test item was applied at a single dose in the conjunctival sac of one eye of each test animal after pulling the lower lid away from the eyeball. The lids were then gently held together for about 1 second in order to prevent loss of the material. The untreated contralateral eye served as control.

Observation period (in vivo):

The animals were observed for 72 hours after dosing.

Number of animals or in vitro replicates:

3

Details on study design:

The test item was ground to a fine powder in a mortar with the help of a pestle.

Approximately 24 hours before the test and immediately prior to the application both eyes of the test animals were examined. A health inspection was performed to ensure the good state of health of the animals. None of the animals showed eye irritation, ocular defects, or pre-existing corneal injury.

The test item was applied at a single dose in the conjunctival sac of one eye of each test animal after pulling the lower lid away from the eyeball. The lids were then gently held together for about 1 second in order to prevent loss of the material. The untreated contralateral eye served as control.

The results of the initial test did not indicate the test item to be corrosive or a severe irritant to the eye using the procedure described. In order to confirm the response, two additional animals were treated in the same manner.

The animals were observed for 72 hours after dosing.

The eyes were examined for signs of irritation throughout the observation period. The eye irritation was scored and recorded according to the grades in the table below. For calculation only the 24 h, 48 h and 72 hour readings were used. At the end of the observation period the treated eyes were examined with the aid of a fluorescein solution (Fluoreszein SE Thilo, Lot H 801, expiry date: 01/2010).

Individual reactions of each animal were recorded at each observation time. Nature, severity and duration of all lesions observed were described. For calculation only the 24 h, 48 h, 72 hour readings were used.

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: not applicable

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: Not applicable

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.66

Max. score:

1

Reversibility:

fully reversible within: 72h

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0.33

Max. score:

1

Reversibility:

fully reversible within: 48h

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: not applicable

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: not applicable

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0.66

Max. score:

1

Reversibility:

fully reversible within: 72h

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: not applicable

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: not applicable

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: not applicable

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

1

Reversibility:

fully reversible within: 48h

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

0

Reversibility:

other: not applicable

Irritant / corrosive response data:

Under the conditions of the present study, single ocular instillation of the test item to rabbits at a dose of 0.1 g produced slightly irritant effects, which were fully reversible within 72 hours in animals no. 1 and 2 and within 48 hours in animal no. 3.

Other effects:

Neither mortalities nor significant clinical signs of toxicity were observed. There were no significant body weight changes during observation period.

Interpretation of results:

GHS criteria not met

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The potential for skin irritation was assessed in vitro, using the EPISKIN test and following the procedure published in Commission Regulation (EC) No 761/2009 (Annex III - B.46). No indication irritancy as indicated by damage of the cultured human skin samples was observed (BSL 2009b). The EPISKIN model has been validated for classification and labelling purposes and therefore, the substance is considered to be non irritating without further testing in animals.

To fulfill requirements for new substance notifications outside the EU, a study for skin irritation in vivo had to be commissioned in 2013. This study confirmed that the substance does not require a hazard label for skin irritation (Bioassay 2013).

The potential for eye irritation was assessed in vivo (BSL 2009c), as there was at that time no in-vitro method that was adequate for classification and labelling purposes and because the substance was found to be non irritating in the skin model. The study followed the principles of GLP and the most recent version of OECD testing guideline 405. The substance caused mild findings in single animals that healed within 72 hours and therefore, it is considered to be non-irritating to eyes.

Justification for classification or non-classification

 Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental test data are reliable and suitable for classification purposes under Regulation 1272/2008. Mean scores (24/48/72h) were below 2.3 and no irreversible findings were observed. As a result the substance is not considered to be classified as a skin irritant under Regulation (EC) No. 1272/2008.

 

Classification, Labelling, and Packaging Regulation (EC) No. 1272/2008

The available experimental study is reliable and suitable for classification purposes under Regulation 1272/2008 as amended for the seventh time in Regulation (EC) No 2015/1221. As a result the substance is not considered to be classified as an eye irritant under Regulation (EC) No. 1272/2008.