1H-Benzimidazole-5,7-disulfonic acid, 2,2'-(1,4-phenylene)bis-, sodium salt (1:2)

Endpoint summary

Description of key information

Eye irritation: not irritating (OECD 405; GLP compliant)
Skin irritation: not irritating (OECD 404: GLP compliant)

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:

1996-03-18 to 1996-03-26

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP study reliable with restrictions Deviations from EU method B.4 (2008): - according to the guideline when responses such as scaling persist to the end of the 14-day observation period, the test substance should be considered an irritant. In this study scaling was observed at 72 hours and on day 7 of the study. After day 7 the observation of the animals was terminated. The study should have been continued at least until day 14 in order to see, if the scaling effect was reversible. Since this did not happen the study has limited reliablity for classification of the test material. - in addition to the observation of irritation, all local toxic effects, such as defatting of the skin, and any systemic adverse effects (e.g. effects on clinical signs of toxicity and body weight), should be fully described and recorded. The systemic adverse effects were not recorded in the study report. - the age of the animals and the animal weights at the conclusion of the test were missing in the study report.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Deviations:

yes

Remarks:

please refer to "Rationale for reliability incl. deficiencies" above

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1992-07-17

Deviations:

yes

Remarks:

Rationale for reliability incl. deficiencies" above

GLP compliance:

yes (incl. QA statement)

Remarks:

Data of inspection March 1996

Species:

rabbit

Strain:

other: stock Mol:Russian

Details on test animals or test system and environmental conditions:

TEST ANIMALS - SPF albino rabbits
- Source: MØllegaard Breeding and Research Centre A/S, Ejby, DK-4623 Lille Skensved
- Weight at study initiation: 2.0 - 2.1 kg
- Housing: during a pre-period of at least one week and throughout the experiment the rabbits were caged individually in PPO/HIPS (Noryl®) cages (floor area: 2576 cm^2) with perforated floor.
- Diet (ad libitum): a pelleted complete rabbit diet "Altromin 2123" from Chr. Petersen, DK-4100 Ringsted
- Water (ad libitum): domestic quality drinking water acidified with hydrochloric acid to pH 2.5 in order to prevent microbial growth
- Acclimation period: a per-period of at least one week

ENVIRONMENTAL CONDITIONS
- Temperature: 21°C ± 3°C
- Relative humidity: 55% ± 15%
- Air changes: 10 times/hour
- Photoperiod (hrs dark / hrs light): 12/12

Type of coverage:

semiocclusive

Preparation of test site:

other: clipped

Vehicle:

water

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):0.5 g of HR 96/N0002 moistened with distilled water

Duration of treatment / exposure:

4 hours

Observation period:

1, 24, 48 and 72 hours as well as 7 days after termination of exposure

Number of animals:

4 female rabbits

Details on study design:

TEST SITE
- Area of exposure and type of wrap used: the day before the experiment was started the rabbits were weighed and an area of 10 X 10 cm on the back was clipped as closely as possible with an electric clipper.
On the experimental day the rabbits were physically restrained on a test table, and the clipped area was divided into four test sites: two anterior located test sites and two posterior located test sites. To each of four gauze patches (2.5 X 2.5 cm) HR 96/N00002 moistened with the vehicle was applied. Indentically 0.5 mL of three other test articles were applied to gauze patches (please refer for results on these three test materials to Section 7.3.1 Skin irritation / corrosion: s_Aarup_1997). The patches were placed on the appropriate test site on the back of each rabbit. The gauze patches were secured with 2.5 cm wide adhesive tape and fixed with Scanpor tape (5 cm width). Thereafter Nobifix (6 cm width) was loosely wound round the trunk. The application schedule of the four test articles are given in the field "Any other information on materials and methods incl. tables" below.

REMOVAL OF TEST SUBSTANCE
- Time after start of exposure: after the exposure time of 4 hours
- Washing: the tape and patches were removed and the treated skin was cleaned with lukewarm water.

SCORING SYSTEM: according to the Draize scale

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #1

Time point:

other: 24, 48 and 72 hours

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: However, at the examination 72 hours after termination of exposure the test site of the rabbit showed slight scale formation. On day 7 few scales were still present but the skin of the test site was intact.

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #1

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #2

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: At the examination 72 hours after termination of exposure the test site of the rabbit showed slight scale formation. On day 7 few scales were still present but the skin of the test site was intact.

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #2

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #3

Time point:

other: 24, 48 and 72 hours

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 7 days

Remarks on result:

other: However, at the examination 72 hours after termination of exposure the test site of the rabbit showed slight scale formation. On day 7 few scales were still present but the skin of the test site was intact.

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #3

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

erythema score

Basis:

mean

Remarks:

animal #4

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Remarks on result:

other: At the examination 72 hours after termination of exposure the test site of the rabbit showed slight scale formation. On day 7 few scales were still present but the skin of the test site was intact.

Irritation parameter:

edema score

Basis:

mean

Remarks:

animal #4

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritant / corrosive response data:

Note: the results given below refer only to HR 96/N00002. For the results on the other applied test materials please refer to Section 7.3.1 Skin irritation / corrosion: s_Aarup_1997.

One hour after termination of exposure the test sites of the four rabbits showed slight skin erythema (grade 1). During the rest of the observation period slight erythema (grade 1) was observed among two rabbits. No oedema was observed in any of the rabbits.
At the examination 72 hours after termination of exposure the test sites of the four rabbits showed slight scale formation.
On day 7 few scales were still present but the skin of the test sites was intact.

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

In conclusion the test materialis considered to be not irritating to the skin.
According to 67/548/EC and subsequent regulations, the test substance is not classified as a skin irritant.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the test substance is not classified as skin irritant.

Executive summary:

According to the outcome of the test, effects observed in 2 of 3 animals on erythema (score ≤1) are fully reversible within 7 days. Hence, no classification is required. However, 72 hours after termination of exposure the test site of the rabbit showed slight scale formation. On day 7 (test end) few scales were still present but the skin of the test site was intact.

According to regulation (EC) 1272/2008:“...inflammation persists to the end of the observation period in 2 or more test animals, taking into consideration alopecia (limited area), hyperkeratosis, hyperplasia and scaling, then a material shall be considered to be an irritant.”Nevertheless, according to the OECD guideline 404 the observation period should be up to 14 days. Since the observation period in this study was chosen to be 7 days only and the fact that only few scales were still present after 7 days but the skin of the test site was already intact, it can safely be assumed that all effects observed would be reversible within 14 days.

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:

1997-08-04 to 1997-08-08

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

GLP study reliable with restrictions Deviation from EU method B.5 (2008): - the age and the sex of the animals was not stated. - the weight of the animals at the end of the study was not stated. - it was not stated if the eyes have been rinsed 1 hour after treatment. According to the guideline if the solid test substance has not been removed from the eye of the test animal by physiological mechanisms at the first observation time point of one hour after treatment, the eye may be rinsed with saline or distilled water. - the study did not follow the recommendation to test only one animal first and then additional animals. - any other lesions in the eye not covered by the Draize scale or non-ocular local adverse effect or adverse systemic effects were not recorded in the study report.

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Deviations:

yes

Remarks:

please refer to "Rationale for reliability incl. deficiencies" above

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

1987-02-24

Deviations:

yes

Remarks:

Rationale for reliability incl. deficiencies" above

GLP compliance:

yes

Species:

rabbit

Strain:

other: stock Mol:Russian

Details on test animals or tissues and environmental conditions:

TEST ANIMALS - SPF albino rabbits
- Source: MØllegaard Breeding and Research Centre A/S, Ejby, DK-4623 Lille Skensved
- Weight at study initiation: 2.4 - 2.6 kg
- Housing: during a pre-period and throughout the experiment the rabbits were caged individually in PPO cages (floor area: 2576 cm^2) with perforated floor.
- Diet (ad libitum): a pelleted complete rabbit diet "Altromin 2123" from Altromin, D-32791 Lage, Lippe
- Water (ad libitum): domestic quality drinking water acidified with hydrochloric acid to pH 2.5 in order to prevent microbial growth
- Acclimation period: pre-period of at least one week

ENVIRONMENTAL CONDITIONS
- Temperature: 20°C ± 3°C
- Relative humidity: 55% ± 15%
- Air changes: 10 times/hour
- Photoperiod (hrs dark / hrs light): 12/12

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 g of the test article was placed in the left eye of the rabbits by gently pulling the lower lid away from the eyeball to form a cup into which the article was given. The lids were then gently held together for 1 second. The right eye remained untreated and served as control.

Duration of treatment / exposure:

not applicable

Observation period (in vivo):

1, 24, 48 and 72 hours as well as 7, 14 and 21 days after treatment

Number of animals or in vitro replicates:

4 rabbits

Details on study design:

The day before testing both eyes of the animals were examined with a hand held inspection lamp fitted with white and UV-light and magnifying glass with 2 x magnification to ensure there were no defects or irritation. The examination was performed before and after instillation of Fluorescein.

SCORING SYSTEM: according to the Draize scale

TOOL USED TO ASSESS SCORE:
After the first 24 hour reading Fluorescein was instilled. After rinsing with 20 mL 0.9% sodium chloride solution the eyes were examined again using UV-light to detect possible corneal damage.
When Fluorescein was used the cornea reactions were scored both before and after the instillation of Fluorescein. The highest score was used for calculation of mean values.

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

animal #1

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Remarks:

animal #1

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #1

Time point:

other: 24, 48 and 72 hours

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

animal #1

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

animal #2

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Remarks:

animal #2

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #2

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

3

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

animal #2

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

animal #3

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Remarks:

animal #3

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #3

Time point:

other: 24, 48 and 72 hours

Score:

0.67

Max. score:

3

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

animal #3

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

mean

Remarks:

animal #4

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

iris score

Basis:

mean

Remarks:

animal #4

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

2

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #4

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

3

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

animal #4

Time point:

other: 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritant / corrosive response data:

One hour after application of the test article all animals showed slight redness of conjunctivae (grade 1). Additionally in two animals slight discharge was seen.
After 24 hours slight redness of conjunctivae was observed in two animal (grade 1).
48 hours after application of the test article only one animal showed slight redness of
conjunctiva (grade 1).
After 72 hours no reactions on the treated eyes were observed.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The test material is non-irritating to the eyes.
According to 67/548/EC and subsequent regulations, the substance is not classified as an eye irritant.
According to the EC Regulation No. 1272/2008 and subsequent regulations, the substance is not classified as an eye irritant.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Additional information

Skin irritation

One reliable animal study described in Aarup (1997) (OECD 404, GLP compliant) is considered to be reliable with restrictions. The substance was determined not to be a skin irritant.

In addition, the same study described in Aarup (1997) tested the test substance as 10% aqueous solution (HR 96/N00002Aq) or 10% oil-in water emulsion (E HR 96/N00002Em) or 10% water-in-oil emulsion vehicle (HR 96/N00002Ve). This information was considered to be reliable with restrictions and is used as supportive information, since the pure test substance was not tested.

The study showed that the 10% aqueous solution or 10% water-in-oil emulsion or 10% oil-in water emulsion vehicle was not irritating to the skin.

Eye irritation

One reliable animal study described in Hoyer (1997) (OECD 405, GLP compliant) is considered to be reliable with restrictions. The substance was determined not to be an eye irritant.

In addition, a reliable animal study described in Aarup (1996) (OECD 405, GLP complaint) is considered to be reliable with restrictions. This study was only used as supportive information, since a aqueous solution of the test substance was tested and not the pure substance. The study showed that the aqueous solution was not irritating to the eye.

Justification for selection of skin irritation / corrosion endpoint:
One reliable animal study described in Aarup (1997) (OECD 404 (1992), GLP compliant) is considered to be reliable with restrictions. The substance was determined not to be a skin irritant.

Justification for selection of eye irritation endpoint:
One reliable animal study described in Hoyer (1997) (OECD 405 (1987), GLP compliant) is considered to be reliable with restrictions. The substance was determined not to be an eye irritant.

Justification for classification or non-classification

Skin irritation

Reference Aarup (1997) is considered as the key study for in vivo skin irritation and will be used for classification. The skin irritation was scored according to the Draize scale. The mean score (24, 48, 72h) for erythema/oedema was ≤ 1 for all animals (n= 4). In addition, scaling was noted at the examination 72 hours and on day 7 after exposure on the test sites of all animals. The study was terminated on day 7.

Discussion:

According to the outcome of the test, effects observed in 2 of 3 animals on erythema (score ≤1) are fully reversible within 7 days. Hence, no classification is required. However, 72 hours after termination of exposure the test site of the rabbit showed slight scale formation. On day 7 (test end) few scales were still present but the skin of the test site was intact.

According to regulation (EC) 1272/2008:“...inflammation persists to the end of the observation period in 2 or more test animals, taking into consideration alopecia (limited area), hyperkeratosis, hyperplasia and scaling, then a materialshall be considered to be an irritant.”Nevertheless, according to the OECD guideline 404 the observation period should be up to 14 days. Since the observation period in this study was chosen to be 7 days only and the fact that only few scales were still present after 7 days but the skin of the test site was already intact, it can safely be assumed that all effects observed would be reversible within 14 days.

Furthermore, no local effects observed in acute dermal toxicity testing and no relevant skin irritating effects observed in skin sensitisation testing support the statement that the substance is not irritating to animal skin.

Eye irritation

Reference Hoyer (1997) is considered as the key study for in vivo eye irritation and will be used for classification. During the study the test item was applied to one eye of four animals each and the eye irritation was scored according to the Draize scale. The mean score (24, 48, 72h) for conjunctivae was ≤ 0.67 for all animals. No other effects were observed. The effects were fully reversible within 72 hours. Thus, according to Regulation (EC) 1272/2008 and subsequent amendments the substance will not be classified as irritating to the eyes.

Respiratory irritation

The classification as respiratory irritant is normally covered under the endpoint specific target organ toxicity- single exposure and repeated exposure. Please refer to the endpoint summaries on acute toxicity (endpoint 7.2) for further information.