Glyoxylic acid

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February 1984

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study was performed according to OECD Guideline No. 405 "Acute Eye Irritation/Corrosion"

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Remarks:

Institut Français de Toxicologie, Les Oncins, BP 109 - 69210 L´Abresie, France

Test material

Test material information

Constituent 1

Reference substance name:

Glyoxylic acid

EC Number:

206-058-5

EC Name:

Glyoxylic acid

Cas Number:

298-12-4

Molecular formula:

C2H2O3

IUPAC Name:

2-oxoacetic acid

Details on test material:

Glyoxylic Acid 50 %
pH-value: 0.3 (at T=21 °C)

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
Six male Albino New Zealand rabbits (per test), weighing about 2.5 kg (+/- 200 g) at the beginning of the study, originating from
accredited breeders.

- Housing:
The rabbits are kept in individual polystyrene cages, measuring 500 x 560 x 360 mm with a perforated polystyrene floor in a ventilated
and air conditioned room.
- Diet: 150 g of complete maintenance food (granulés Lapin Entretien "112" UAR, 91360 - Villemoisson/ Orge) is provided per rabbit and
per day.
- Water: provided ad libitum
- Acclimation period:
Before the start of the experiment, the animals are kept for at least 8 days to allow time for acclimatization. They were vaccinated against
the principal respiratory (pasteurellosis) and digestive diseases of the rabbit (Lysopast and Oventero; Institut Mérieux) and myxomatosis
(lyomyxovax; Institut Mérieux). Within the 24 hrs before the instillation, these animals are selected at random, after elimination of animals
showing possible ocular lesions.
One ear of each animal is pierced and a metal tag (Chevillot: La Quick) is attached for individual identification.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 °C +/- 3 (throughout the year)
- Humidity (%): 30 - 70 %
- Air changes (per hr): 12 - 14 times per hour (pre filtered air: 5-10 µ)
- Photoperiod (hrs dark / hrs light): 12 hrs artificial light at each 24 hour period

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.1 ml of the test substance

Duration of treatment / exposure:

The eyes of 3 rabbits were washed out 4 seconds after instillation and the eyes of 3 other animals 30 seconds after the application of the test substance.

Observation period (in vivo):

1 hour after the instillation, and then at Day 1 (24 hrs), Day 2, Day 3, Day 4 and Day 7

Number of animals or in vitro replicates:

6

Details on study design:

Method of administration:
Each rabbit is immobilized in a plastic restraining box (Iffa Crédo). The test substance is introduced into the inferior conjunctival sac
of the right eye. The left eye serves as control. The upper and lower eyelids are held together for several seconds to avoid any loss of test
substance.
The animals are restrained for 4 hours, and then replaced in individual cages.
The eyes of 3 rabbits are washed out 4 seconds after instillation, care being taken not to cause injury. The eyes of the other 3 rabbits
were rinsed 30 seconds after the application of the test substance. About 50 ml of the rinsing solution at about 20 °C is administered using a plastic jet at moderate pressure.
The control eye is washed out under the same conditions as the treated one.
The excess of liquid is immediately wiped away with a Codex hydrophilic gauze pad.

Ocular examinations:
For examination of the eyes, the animals are immobilized on a table, and both eyes are comparatively examined.
These examinations are always carried out under the same conditions in particular for the lighting. They are made by comparison with the control eye, 1 hour after the instillation, and then at Day 1 (24 hrs), Day 2, Day 3, Day 4 and Day 7. If the seven days observation is insufficient for fully evaluation the reversibility or the irreversibilty of the lesions observed, it might be extended (maximum: 21 days).
Observation of the condition of the cornea are made with the aid of a Heine´s ophthalmoscope (Microflex). The ophthalmoscope may also used to observe the iris, pupil and lens. A supplementary examination may be performed with a slit-lamp (Haag-Streit).
Ocular examinations are carried out at each above mentioned period, and for each rabbit, according to the following scale, and in the
following order:

Conjunctival lesions and discharge
An alteration of the palpebral or bulbar conjunctiva is minor compared with corneal opacification or a lesion of the iris and pupil. The
anomalies found in the conjunctiva are scored according to the following numerical scale:

Chemosis (oedema):
No swelling: 0
Slight swelling, including the nictitating membrane: 1
Obvious swelling with partial eversion of the lids: 2
Swelling with lids about half closed: 3
Swelling with lids about half closed to completely closed: 4

Discharge:
Absence of discharge: 0
Slight discharge (does not include small amounts normally found in inner canthus): 1
Discharge with moisening of lids and hairs adjacent to lids: 2
Discharge with moistening of lids and hairs on considerable area around the eye: 3
B beeing the value obtained
(Note: The evaluation of disacharge and swelling should be conducted before opening the lids of the animals)

Conjunctival Enanthema (visible by pulling open the eyelids):
Vessel normal: 0
Vessels definitely injected above normal: 1
More diffuse, deeper crimson red, individual vessels not easily discernable: 2
Diffuse dark redness: 3
C beeing the value obtained

Pupillary and iridial lesions
Pupil: Its dimensions, form and position are compared with the control eye. The pupillary DIRECT PHOTOMETER REFLEX (contraction of iris to reduce pupil size) is observed by shining a bright light into the eye (miosis).
Iris: The iris is examined with direct lighting, with an electric torch, and then lighting from the side. The colour, uniformity and texture are
observed. Alterations in the pupil or iris are second using the following numerical scale:
No anomaly: 0
Iris clearly more folded than normal, congestion, swelling, circumcorenal injections (any one or all of these), iris still reacting to light with
reflex contraction (sluggish reaction is positive): 1
No reaction to light, haemorrhage, important destruction (any one or all of these): 2

Corneal lesions:
The cornea is normally glossy, transparent and without any visible blood vessels.
To determine the presence or absence of corneal opacification and to evaluate the affected area, one or two drops of aqueous solution of
sodium fluorescein at 2% (Faure) are instilled in the eye. Excess fluorescein is rinsed with the rinsing solution (Dacryoserum), and then immediately wiped with a gauze pad. If corneal opacification is difficult to determine, an additional examination is carried out in a dark room, with a U.V. lamp, 254 and 366 nm wavelength (Mineralight lamp: model UVSL-25).
Fluorescein examination is not carried out for readings at time 1 hour.
Quantitative evaluations of the degree and the extent of opacity of the cornea are scored according to the following scale:

Degree of opacity (the most opaque area is chosen for the reading):
No opacity, Neither loss of brillance nor gloss: 0
Translucent zone diffuse or scattered, details of iris clearly visible: 1
Translucent zone easily discernible, details of iris slightly obscured: 2
Opalescent zone, no details of iris visible, size of pupil barely discernible: 3
Cornea completely opaque, iris invisible: 4
E beeing the value obtained

Area of cornea affected
One quarter (or less) but not zero: 1
Greater than one quarter, but less than half: 2
Greater than one half, but less than three quarters: 3
Greater than three quarters, up to whole area: 4
F beeing the value obtained

A qualitative evaluation of any ulceration or granulation of the cornea is conducted to determine the irrative capacity of the test substance:

Ulceration (loss of substance with or without swelling of the eye)
No ulceration: 0
Presence of ulceration: U

Area affected
One quarter: a
Greater than one quarter, but less than half: b
Greater than one half, but less than three quarters: c
Greater than three quarters up to whole area: d
(the best method for demonstrating the nature and degree of this lesion is the fluorescein test previously described)

Granulous dystrophy (multiple blisters spread over the corneal epihelium):
No granulation: 0
Presence of granulation: G

Area affected:
One quarter (or less) but not zero: a
Greater than one quarter, but less than half: b
Greater than one half, but less than three quarters: c
Greater than three quarters up to whole area: d
(When there is an hesitation between the two scores of the evaluation scale of the lesions, the superior one is chosen)
If the degree of irritation is very weak, the score is counted as positive only if the irritated eye is really different from the control one.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

chemosis score

Basis:

mean

Remarks:

of all (6) animals

Time point:

24/48/72 h

Score:

3.94

Max. score:

4

Reversibility:

not reversible

Results 2

Irritation parameter:

conjunctivae score

Remarks:

Discharge

Basis:

mean

Remarks:

of all (6) animals

Time point:

24/48/72 h

Score:

1.83

Max. score:

3

Reversibility:

not reversible

Results 3

Irritation parameter:

conjunctivae score

Remarks:

Erythema

Basis:

mean

Remarks:

of all (6) animals

Time point:

24/48/72 h

Score:

2.22

Max. score:

3

Reversibility:

not reversible

Results 4

Irritation parameter:

iris score

Remarks:

Congestion

Basis:

mean

Remarks:

of all (6) animals

Time point:

24/48/72 h

Score:

1.78

Max. score:

2

Reversibility:

not reversible

Results 5

Irritation parameter:

cornea opacity score

Remarks:

opacity

Basis:

mean

Remarks:

of all (6) animals

Time point:

24/48/72 h

Score:

3.83

Max. score:

4

Reversibility:

not reversible

Irritant / corrosive response data:

highly irritating and corrosive

Applicant's summary and conclusion

Interpretation of results:

highly irritating

Remarks:

Migrated information

Conclusions:

Highly irritating.
Risk of serious damage to eyes.

Executive summary:

In a primary eye irritation study according to OECD TG 405, 0.1 ml of a 50 % solution of Glyoxylic Acid was instilled into the inferior conjunctival sac of the right eye of six male Albino New Zealand rabbits. The left eye served as control. The eyes were washed out 4 seconds (3 animals) and 30 seconds (3 animals) after instillation. Examinations were carried out by comparison with the control eye, 1 hour after the instillation, and then at Day 1 (24 hrs), Day 2, Day 3, Day 4 and Day 7. Glyoxylic Acid 50% caused severe damage to the treated eyes, demonstrating that Glyoxylic Acid 50% is extremely irritating to the rabbit eye.