Arsenic

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2011-06-27 to 2011-07-19

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Version / remarks:

2002-04-24

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Arsenic

EC Number:

231-148-6

EC Name:

Arsenic

Cas Number:

7440-38-2

Molecular formula:

As

IUPAC Name:

arsenic

Details on test material:

- Name of test material (as cited in study report): Arsenic metal, powder (particle size < 0.2 mm, purity > 99.99%)
- Physical state: powder
- Storage condition of test material: at room temperature, under N2 atmosphere
- Particle size distribution: D10 = 18.24 µm; D50 = 93.65 µm; D90 = 176.67 µm
- Particle size: < 0.2 mm

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Age at study initiation: 15 weeks
- Weight at study initiation: 2835 g
- Housing: individually in stainless steel cages
- Diet (ad libitum): pelleted standard Teklad Global High Fiber Rabbit Diet 2031C (batch no. 80/10, Provimi Kliba AG, 4303 Kaiseraugst / Switzerland); a piece of wood (batch no. 122201, imported by Indulab AG, Gams / Switzerland from ABEDD® - LAB & VET GmbH, 1160 Vienna / Austria) and a haystick 4642 (batch no. 37/10, Provimi Kliba AG, 4303 Kaiseraugst / Switzerland) were also provided for environmental enrichment.
- Water (ad libitum): community tap water from Itingen
- Acclimation period: 5 days; under laboratory conditions after health examination. Only animals without any visual signs of illness were used for the study.

ENVIRONMENTAL CONDITIONS
- Temperature: 17-23 °C
- Relative humidity: 30-70% (values above 70% were transiently observed during room cleaning)
- Air changes: 10-15 air changes per hour
- Photoperiod (hrs dark / hrs light): 12/12 (music played during the daytime light period.)

Test system

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): the test item was placed as a weight of 0.1 g/animal in the conjunctival sac of the left eye after gently pulling the lower lid away from the eyeball. The lid was then gently held together for about one second to prevent a loss of test item. The right eye remained untreated and served as the control.

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

at approximately 1, 24, 48 and 72 hours as well as 7, 10, 14, 17 and 21 days after test item instillation

Number of animals or in vitro replicates:

1 male rabbit
(as it was suspected that the test item might produce irritancy, a single animal was treated first and the treatment of two further animals was delayed. Due to severe signs of irritation or corrosion observed in the first animal and for animal welfare reasons, further animals were not instilled with the test item.)

Details on study design:

The eyes of the animals were examined one day prior to test item administration. Only animals with no signs of ocular injury or irritation were used in the test.

REMOVAL OF TEST SUBSTANCE
- Washing: the eye of the test animal was rinsed with 0.9% saline solution after 24 hours after instillation of the test item, since residues of the solid test item had not been removed from the eye of the test animal by physiological mechanisms at the first observation time point of 1 hour after treatment. After 2, 3, 4, 7 and 10 days after instillation of the test item, a washing out with saline was used in order to remove ocular discharge for evaluation of eye irritation.

SCORING SYSTEM: according to the Draize scale
Scleral reddening and ocular discharge were also assessed (scale for assessment can be seen in the field "Any other information on materials and methods incl. tables" below).

TOOL USED TO ASSESS SCORE:
Eye examinations were made with a Varta Cliptrix diagnostic-lamp (Roth AG, 4153 Reinach / Switzerland).

OBSERVATIONS:
- Viability / Mortality: daily from acclimatization of the animals to the end of the observation period.
- Clinical Signs (systemic): daily from acclimatization of the animals to the end of the observation period.
- Body Weights: at start of acclimatization, on the day of application and at the end of the observation period.
- Pathology: no necropsy was performed on the animal sacrificed at termination of observation.
The animal was sacrificed by intravenous injection of 1.0 mL/kg body weight of a solution of 162 mg/mL sodium pentobarbitone into the ear vein and discarded.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 21 days

Remarks on result:

other: During the 1-hour and 24 hour observation the corneal opacity could not be scored due to swelling of the conjunctivae.

Results 2

Irritation parameter:

iris score

Basis:

mean

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

not fully reversible within: 21 days

Remarks on result:

other: During the 1-hour and 24 hour observation the iris light reflex could not be scored due to swelling of the conjunctivae.

Results 3

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

24/48/72 h

Score:

3

Max. score:

3

Reversibility:

not fully reversible within: 21 days

Results 4

Irritation parameter:

chemosis score

Basis:

mean

Time point:

24/48/72 h

Score:

4

Max. score:

4

Reversibility:

not fully reversible within: 21 days

Irritant / corrosive response data:

The instillation of Arsenic Metal, Powder <0.2 mm, >99.99% into the eye of the male rabbit resulted in corneal opacity (grade 2: easily discernible translucent area with details of iris obscured) in an involved corneal area greater than three quarters and in markedly deepened rugae, congestion, swelling, moderate circumcorneal hyperemia or injection of the iris with iris still reacting to light (iris light reflex, grade 1) and in diffuse beefy red conjunctivae (grade 3) and in chemosis (swelling with lids more than half-closed, grade 4)[description of mean values across the scoring times 24, 48 and 72 hours after instillation of the test item].
The sclera was not accessible due to swelling on day 1 and the sclera, iris and cornea were also not accessible on day 2. Marked and moderate redness of the sclera was noted from day 10 onwards. Additionally, slight, moderate or marked discharge, test item remnants and/or mucus were noted from day 2 onwards.
The eye irritation scores increased after 72 hours (during days 7 to 17) for corneal opacity and iris light reflex, and slightly decreased after 10 or 14 days for reddening of the conjunctivae and chemosis.
The effects were not reversible after 21 days.
The marked signs of eye irritation were considered not to result from mechanical effects of the test item on the eye, since test item remnants were removed by rinsing the eye with saline, since severity grades and nature of findings such as corneal opacity, iritis or chemosis increased even after eye rinsing and since findings were not reversible during 21 days.

Other effects:

- Viability / Mortality: no intercurrent death occurred during the course of the study.
- Clinical Signs: no clinical signs were recorded throughout the entire observation period.
- Body Weights: the body weight was within the range commonly recorded for this strain and age.
- Pathology: no necropsy was performed at the end of the study.

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye)

Conclusions:

Arsenic metal powder <0.2 mm, >99.99% is considered to cause irreversible effects on the eyes.
According to the criteria specified by Directive 67/548/EEC and subsequent regulations, the test item is classified as risk of serious damage to eyes (R41).
According to the EC Regulation No. 1272/2008 and subsequent regulations, the test item is classified as Category 1.