Registration Dossier

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Description of key information

For assessment of the skin and eye irritating potential of Glyoxal 40% aqueous solution, an EpiDerm Corrosivity Test in vitro (BASF AG 61H0150/022020), an in vivo skin irritation test (BASF AG 85/16) and two in vivo eye irritation tests (BASF AG 85/16 and BASF AG XIII/258) were assessed in a weight of evidence approach. The EpiDerm Corrosivity test was conducted prior to the implementation of OECD TG 431 (2004) but both, conduct and test system used, were guideline conform; the skin irritation test was OECD TG 404 (1981) conform. The first eye irritation test was conducted according to the OECD TG 405 (1981) whereas the conduct of the second study was based on an internal BASF testing method, which in principle was similar to the OECD TG 405. All studies were considered as weight of evidence.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Referenceopen allclose all

Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1963
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
The test was conducted according to a BASF internal test method, which in principle was similar to OECD 404, however with following deviations: Exposure periods of 1, 5,15 minutes and 20 h (OECD recommendation: 4 h); Testing of the ear (not recommended by the OECD guideline); Time point 72 h not considered; Observation period of 8 days instead of 14 as recommended by OECD guideline. These deviations did not affect the validity and reliability of the findings; the study is scientifically acceptable.
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Version / remarks:
(1981)
Principles of method if other than guideline:
The test was conducted according to an internal BASF test method, which in principle was similar to OECD 404.
BASF-TEST:
White Vienna rabbits were used. Usually, 2 animals were treated for 1, 5, 15 min and 20 h using occlusive conditions. An application site of 2.5 x 2.5 cm was covered with the liquid test substance. In addition, skin tissue from the ear was tested by wrapping the ear. These results from the ear, however, would not be taken into account for evaluation as they do not represent testing of the dorsal/lateral flank of the back. After the application time, the skin was washed with water which sometimes contained a mild detergent. The animals were observed for 8 days. Skin reaction was recorded after 1h, 24h, 48h, 72h, 96h and after 7 and 8 days.
GLP compliance:
no
Remarks:
GLP was not compulsory at the time the study was conducted
Species:
rabbit
Type of coverage:
occlusive
Preparation of test site:
shaved
Vehicle:
other: none as the test substance was applied unchanged
Controls:
other: untreated skin of the same animal served as control
Amount / concentration applied:
the test substance was applied undiluted to the skin using a patch soaked with test material; the applied amount was about 1 mL.
Duration of treatment / exposure:
Dorsal skin: 1, 5, 15 min
Dorsal skin: 20 h
Ear: 20 h
Observation period:
The animals were observed following exposure for 8 days on working days. Skin changes were recorded after removal of the bandage as well as after 1h, 24h, 48h, 72h, 96 h and after 7 and 8 days.
Number of animals:
Four animals were used.
Details on study design:
- Each animal received an application of test material to the clipped dorsal skin of the trunk and to the ear. The test material was used unchanged at a volume of 1 mL and the application site was maintained under occlusive conditions. 
-Following application periods of 1, 5 and 15 minutes (dorsal skin),  dressing was removed and the application site was rinsed with Lutrol and  Lutrol in water (1:1).
- Following application periods of 20 hours (dorsal skin and ear), the  dressing was removed but the application site was not rinsed.  The animals were observed and skin findings were recorded over a period  of 8 days following treatment.
-The skin findings, which had been originally scored according to a BASF  scoring system, were re-scored according to the OECD Draize scoring  system; for this purpose, only the findings of the 20-hour dorsal application were considered at the time point 24 and 48 hours (no 72 h data provided).
Irritation parameter:
erythema score
Remarks:
1 min and 5 min exposure
Basis:
mean
Time point:
24 h
Score:
2
Reversibility:
fully reversible within: 8 days
Irritation parameter:
erythema score
Remarks:
15 min exposure
Basis:
mean
Time point:
24 h
Score:
2
Reversibility:
not fully reversible within: 8 days
Remarks:
distinct scaling
Irritation parameter:
erythema score
Remarks:
20 h exposure
Basis:
mean
Time point:
24 h
Score:
2
Reversibility:
not fully reversible within: 8 days
Remarks:
necrosis
Irritation parameter:
edema score
Remarks:
15 min exposure
Basis:
mean
Time point:
24 h
Score:
2
Reversibility:
not fully reversible within: 8 days
Remarks:
distinct scaling
Irritation parameter:
edema score
Remarks:
20 h exposure
Basis:
mean
Time point:
24 h
Score:
3
Reversibility:
not fully reversible within: 8 days
Remarks:
necrosis
Other effects:
- After 1 and 5 minutes: at reading time point 24 hour, slight erythema was seen; full reversibility was reported for day 8.
- After 15 minutes: at reading time point 24 hours, slight edema and slight erythema were observed; at day 8 fine scaling was seen, indicating partial reversibility.
- After 20 hours: erythema, edema and slight skin defects were seen within 24 h; eschar formation and slight necrosis were seen within 8 days.

The 20-hour dorsal treatment which was relevant for assessment resulted in erythema and edema; after 8 days, severe necrosis was seen, indicating no reversibility.

Interpretation of results:
Category 2 (irritant) based on GHS criteria
Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1970
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: see 'Remark'
Remarks:
The test was conducted according to a BASF internal test method, which in principle was similar to OECD 404, however with following deviations: -Exposure periods of 1, 5,15 minutes and 20 h (OECD recommendation: 4 h); - Testing of the ear (not recommended by the OECD guideline); - Time point 72 h not considered; - Observation period of 8 days instead of 14 as recommended by OECD guideline. These deviations did not affect the validity and reliability of the findings; the study is scientifically acceptable.
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Version / remarks:
(1981)
Principles of method if other than guideline:
The test was conducted according to an internal BASF test method, which in principle was similar to OECD 404.
BASF-TEST:
White Vienna rabbits were used. Usually, 2 animals were treated for 1, 5, 15 min and 20 h using occlusive conditions. An application site of 2.5 x 2.5 cm was covered with the liquid test substance. In addition, skin tissue from the ear was tested by wrapping the ear. These results from the ear, however, would not be taken into account for evaluation as they do not represent testing of the dorsal/lateral flank of the back. After the application time, the skin was washed with water which sometimes contained a mild detergent. The animals were observed for 8 days. Skin reaction was recorded after 1h, 24h, 48h, 72h, 96h and after 7 and 8 days.
GLP compliance:
no
Remarks:
GLP was not compulsory at the time the study was conducted
Species:
rabbit
Strain:
Vienna White
Details on test animals or test system and environmental conditions:
Two animal were used, each weighing about 2 kg
Type of coverage:
occlusive
Preparation of test site:
shaved
Vehicle:
other: none as the test substance was applied unchanged
Controls:
other: untreated skin of the same animal served as control.
Amount / concentration applied:
the test substance was applied undiluted to the skin using a patch soaked with test material; the applied amount was about 1 mL.
Duration of treatment / exposure:
Dorsal skin: 1, 5, 15 min
Dorsal skin: 20 h
Ear: 20 h
Observation period:
The animals were observed following exposure for 8 days on working days. Skin changes were recorded after removal of the bandage as well as after 1h, 24h, 48h, 72h, 96 h and after 7 and 8 days.
Number of animals:
Four animals were used.
Details on study design:
- Each animal received an application of test material to the clipped dorsal skin of the trunk and to the ear. The test material was used unchanged at a volume of 1 mL and the application site was maintained under occlusive conditions.
- Following application periods of 1, 5 and 15 minutes (dorsal skin), dressing was removed and the application site was rinsed with Lutrol and Lutrol in water (1:1).
- Following application periods of 20 hours (dorsal skin and ear), the dressing was removed but the application site was not rinsed. The animals were observed and skin findings were recorded over a period of 8 days following treatment.
- The skin findings, which had been originally scored according to a BASF scoring system, were re-scored according to the OECD Draize scoring system; for this purpose, only the findings of the 20-hour dorsal application were considered at the time point 24 and 48 hours (no 72 h data provided).
Irritation parameter:
erythema score
Remarks:
1 min, 5 min, 15 min exposure
Basis:
mean
Time point:
24 h
Score:
2
Reversibility:
fully reversible within: 8 days
Remarks:
yellow coloration was still apparent
Remarks on result:
other: glyoxal pure, glyoxal crude
Irritation parameter:
erythema score
Remarks:
20 h exposure
Basis:
mean
Time point:
24 h
Score:
3
Reversibility:
not fully reversible within: 8 days
Remarks:
slight formation of crusts and superficial necrosis
Remarks on result:
other: glyoxal pure, glyoxal crude
Irritation parameter:
edema score
Remarks:
20 h exposure
Basis:
mean
Time point:
24 h
Score:
> 2 - <= 3
Reversibility:
not fully reversible within: 8 days
Remarks:
slight formation of crusts and superficial necrosis
Remarks on result:
other: glyoxal pure, glyoxal crude
Other effects:
- Dorsal application of Glyoxal pure 40% for 1, 5 and 15 minutes: questionable spotted erythema and yellowing of the skin was observed 24 h after exposure. After 8 days, only yellowing of the skin remained.
- Dorsal application of Glyoxal technical grade 40% for 1, 5 and 15 minutes: slight spotted erythema and yellowing of the skin was observed 24 h after exposure. After 8 days, only yellowing of the skin remained.
- Application of Glyoxal pure 40% and of Glyoxal technical grade 40% to the ear: For both substances, the 20 h-exposure resulted in slight erythema, slight to well-defined edema and in inflammatory lesions 24 h after the application; after 8 days, scar formation was reported for Glyoxal pure whereas superficial necrosis was reported for Glyoxal of technical grade.

The 20-h dorsal treatment, which was relevant for assessment, resulted in moderate to severe erythema and in edema. After 8 hours, scar formation and superficial necrosis were reported for Glyoxal 40% pure and Glyoxal 40% technical grade, respectively. Thus, no fully reversibility could be noted at the test ending.

Interpretation of results:
Category 2 (irritant) based on GHS criteria
Endpoint:
skin irritation: in vitro / ex vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
2002
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Remarks:
The study was conducted prior to the implementation of OECD 431 (2004) but both, conduct and test system used, were guideline conform
Qualifier:
equivalent or similar to guideline
Guideline:
other: OECD 431 (2004)
Principles of method if other than guideline:
The study was conducted 2002, i.e. prior to the implementation of the OECD TG 431 (2004). However, both, the test conduct and test system used were guideline conform.
Test principle:
The EpiDermTM Corrosivity-Test is an in vitro test procedure used for the detection of the corrosive potential of a test substance.
Corrosive materials are identified by their ability to produce a decrease in cell viability, as determined, for example, by using the MTT reduction assay, below defined threshold levels at specified exposure periods. The principle of the human skin model assay is based on the hypothesis that corrosive chemicals are able to penetrate the stratum corneum by diffusion or erosion, and are cytotoxic to the underlying cell layers.
The test material was applied unchanged topically to a three-dimensional human skin model comprising at least a reconstructed epidermis with a functional stratum corneum for 3 minutes and 1 hour. Negative and positive controls were added.
GLP compliance:
no
Specific details on test material used for the study:
SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: B52

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Stability under test conditions: Glyoxal as 40% aqueous solution is stable for 6 months
Test system:
human skin model
Remarks:
The test system consisted of a three-dimensional human skin model, comprising at least a reconstructed epidermis with a functional stratum corneum.
Vehicle:
unchanged (no vehicle)
Controls:
not required
Amount / concentration applied:
undiluted
Duration of treatment / exposure:
Three minutes and one hour
Observation period:
Not applicable
Number of animals:
Not applicable
Details on study design:
TEST DESIGN
The test material was applied unchanged topically to a three-dimensional human skin model comprising at least a reconstructed epidermis with a functional stratum corneum for 3 minutes and 1 hour. Negative and positive controls were added.
The decrease in cell viability as indicator for corrosivity was determined by using the MTT reduction assay (i.e. [3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide]. For this purpose, two replicates of treated skin sample are placed in an MTT solution of appropriate concentration (e.g. 0.3 – 1 mg/mL) at appropriate incubation temperature for 3 hours. The precipitated blue formazan product is then extracted using a solvent (isopropanol), and the concentration of the formazan is measured by determining the optical density (OD) at a wavelength of 570 nm.
The mean OD for the test substance was compared with that of the negative control (cell viability arbitrarily set at 100%) and the cell viability of the treated samples was expressed as percentage, relative to the negative control.

EVALUATION CRITERIA
The evaluation criteria for prediction of corrosivity are the followings:
The test substance is considered to be corrosive to skin, (1) if the viability after 3 minutes exposure is less than 50%, or (2) if the viability after 3 minutes exposure is greater than or equal to 50 % and the viability after 1 hour exposure is less than 15%.
The test substance is considered to be non-corrosive to skin if the viability after 3 minutes exposure is greater than or equal to 50% and the viability after 1 hour exposure is greater than or equal to 15%.
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
3 min exposure
Value:
95
Irritation / corrosion parameter:
% tissue viability
Run / experiment:
1 hour exposure
Value:
45

- After 3 minutes of exposure, a mean optic density for the Glyoxal- treated skin samples of 1.751 was determined, versus 1.841 for the negative control, indicating a cell viability of 95% when compared to control (100%).

- After 1 hour of exposure, a mean optic density for the Glyoxal- treated skin samples of 0.758 was determined, versus 1.687 for the negative control, indicating a cell viability of 45% when compared to control (100%).

- For the positive control, an OD of 0.383 and 0.225 was determined after 3 minutes and 1 hour of exposure, respectively. The corresponding cell viabilities were 22% and 13% and confirmed the adequate performance of the test and the validity of the results.

Interpretation of results:
study cannot be used for classification
Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1985
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Qualifier:
according to guideline
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
Version / remarks:
(1981)
GLP compliance:
no
Remarks:
in fact, the study was carried out in a GLP certified laboratory. However, the study was not monitored by the QAU; therefore, the study was not fully compliant to GLP requirements.
Specific details on test material used for the study:
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Stability under test conditions: Glyoxal as 40% aqueous solution is stable for 6 months

OTHER
- Impurities (identity and concentrations): ethylene glycol, glycol aldehyde, formaldehyde, formic acid, glycolic acid, glyoxylic acid
- Composition of test material, percentage of components: 40% Glyoxal in water, ethylene glycol 0.6%, glycol aldehyde 0.15%, formaldehyde 0.015%, formic acid, glycolic acid, glyoxylic acid, 0.1%

Species:
rabbit
Strain:
Vienna White
Details on test animals or test system and environmental conditions:
TEST ANIMALS
- Source: Gaukler, Offenbach/Main, Germany (animal breeder)
- Weight at study initiation: 2.72, 3.04 and 2.36 kg (3 animals)
- Housing: single housing in cages of stainless steel with wiremesh walk floors, floor area 40 cm x 51 cm
- Diet (e.g. ad libitum): Kliba 341, 4 mm; Klingentalmuehle AG, Kaiseraugst, Switzerland, about 130 g/animal and day
- Water (e.g. ad libitum): Tap water, about 250 ml/ animal and day
- Acclimation period: at least 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Air changes (per hr): housing in fully air-conditioned rooms
- Photoperiod (hrs dark / hrs light): 12 h/12 h


Type of coverage:
semiocclusive
Preparation of test site:
other: Clipping of the fur at least 15 hours prior testing
Vehicle:
unchanged (no vehicle)
Controls:
other: the untreated skin on the left flank of each animal served for comparison.
Amount / concentration applied:
0.5 mL
Duration of treatment / exposure:
4 hours
Observation period:
72 hours
Number of animals:
Three females
Details on study design:
- The test substance was used as delivered and was applied to the skin by means of a 2.5 x 2.5 cm test patch, which was wetted with the test substance;
- The test material was applied to the clipped skin on the right flank of each rabbit;
- The application site was covered with a porous semi-occlusive dressing for 4 hours;
- At the end of the treatment, the dressing was removed and the application site was rinsed with Lutrol, and with Lutrol:water (1:1);
- During 72 hours following treatment, the application sites were examined at different time points for skin reaction (4h, 24h, 48h and 72h);
- Scoring of skin findings was based on Draize (1959); calculation of the mean was done according to the 83/467/EEC criteria (July 29th 1983)
- For calculation of the mean erythema and mean edema scores, the reading scores at 24, 48 and 72 hours were considered;
- The animals further were observed for symptoms of toxicity and were sacrificed for necropsy at study ending.
Irritation parameter:
erythema score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: no effect was seen
Irritation parameter:
erythema score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: no effect was seen
Irritation parameter:
erythema score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: no effect was seen
Irritation parameter:
edema score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: no effect was seen
Irritation parameter:
edema score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: no effect was seen
Irritation parameter:
edema score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
4
Reversibility:
other: not applicable
Remarks on result:
other: no effect was seen
Other effects:
No treatment-related effects were reported.
Interpretation of results:
GHS criteria not met
Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Eye irritation

Link to relevant study records

Referenceopen allclose all

Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1970
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Version / remarks:
(1981)
Deviations:
yes
Remarks:
volume of 0.05 mL applied (OECD: 0.1 mL); 2 animals used (OECD: 3); observation period was 8 days (OECD: 21); examination using fluorescein (OECD: no use of fluorescein)]
Principles of method if other than guideline:
The test was conducted according to an internal BASF test method, which in principle was similar to OECD 404.
BASF-TEST:
Before OECD guideline 405 was established, eye irritation was tested using an internal method. White Vienna rabbits were used. Usually approximately 50 µl of the test substance were applied to the conjunctival sac of one eye of each of 2 animals. The non- or saline- treated eye served as control. In studies with solids, talcum powder was used as control. The animals were observed several times on the treatment day and up to 8 days afterwards, and findings were recorded on working days.
The eyes were not washed out after 24 h as specified in OECD Guideline 405, which could be critical for solids which thus remained on the cornea for several days, causing mechanical damage. Probably, this would have been less severe if it had been washed out after 1 day.
GLP compliance:
no
Remarks:
GLP was not compulsory at the time the study was conducted
Species:
rabbit
Strain:
Vienna White
Details on test animals or tissues and environmental conditions:
Two animals, a male and a female, were used; each animal weighed about 2 kg.
Vehicle:
unchanged (no vehicle)
Controls:
other: the untreated eye of each animal served as control
Amount / concentration applied:
ca. 0.05 mL of undiluted test material was instilled in the conjunctival sac of the right eye of each animal.
Duration of treatment / exposure:
Not applicable as the test substance was not washed out.
Observation period (in vivo):
8 days
Number of animals or in vitro replicates:
Two animals were used
Details on study design:
- Following application, the animals were examined for corneal changes, iris effects and conjunctival reaction at following reading time points: 1, 24, 48 hours and at day 8;
-The eye findings, which had been originally scored according to a BASF scoring system;
- For evaluation, the BASF scores given in the raw data were converted into Draize scores.
Irritation parameter:
cornea opacity score
Basis:
mean
Time point:
24 h
Score:
> 1 - <= 3
Reversibility:
not fully reversible within: 8 days
Remarks:
opacity grade 1
Remarks on result:
other: glyoxal pure, glyoxal crude
Irritation parameter:
conjunctivae score
Basis:
mean
Time point:
24 h
Score:
1
Reversibility:
not fully reversible within: 8 days
Remarks on result:
other: glyoxal pure, glyoxal crude
Irritation parameter:
chemosis score
Basis:
mean
Time point:
24 h
Score:
> 3 - <= 4
Reversibility:
not fully reversible within: 8 days
Remarks on result:
other: glyoxal pure, glyoxal crude

- After instillation of pure Glyoxal, a slight corneal opacity was observed up to reading time point 72 hours, thereafter, corneal opacity was no longer observed. Technical grade Glyoxal induced cloudy to milky corneal opacity that still was evident on day 8, even though having turned into slight opacity.

- Glyoxal pure and Glyoxal technical grade instilled unchanged into the conjunctival sac caused a clear reddening and very strong inflammation on the conjunctiva.

- No effects were seen in the iris.

- Referring to reversibility, at day 8 post treatment, slight reddening and chemosis were still seen in the eyes treated with pure Glyoxal whereas the eyes treated with the technical grade material showed slight reddening, slight chemosis (one of the two animals treated), slight corneal opacity and scarification of the upper eyelid.

Interpretation of results:
Category 2 (irritating to eyes) based on GHS criteria
Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1985
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
The study was not monitored by the QAU; therefore, the study was not fully compliant to GLP requirements
Qualifier:
according to guideline
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Version / remarks:
(1981)
GLP compliance:
no
Remarks:
the study was carried out in a GLP certified laboratory. However, the study was not monitored by the QAU; therefore the study was not fully compliant to GLP requirements.
Specific details on test material used for the study:
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Stability under test conditions: Glyoxal as 40% aqueous solution is stable for 6 months

OTHER
- Impurities (identity and concentrations): ethylene glycol, glycol aldehyde, formaldehyde, formic acid, glycolic acid, glyoxylic acid
- Composition of test material, percentage of components: 40% Glyoxal in water, ethylene glycol 0.6%, glycol aldehyde 0.15%, formaldehyde 0.015%, formic acid, glycolic acid, glyoxylic acid, 0.1%
Species:
rabbit
Strain:
Vienna White
Details on test animals or tissues and environmental conditions:
TEST ANIMALS
- Source: Gaukler, Offenbach/Main, Germany (animal breeder)
- Weight at study initiation: 3.08 kg, 3.53 kg and 2.99 kg (3 animals)
- Housing: single housing in cages of stainless steel with wiremesh walk floors, floor area 40 cm x 51 cm
- Diet (e.g. ad libitum): Kliba 341, 4 mm; Klingentalmuehle AG, Kaiseraugst, Switzerland, about 130 g/animal and day
- Water (e.g. ad libitum): Tap water, about 250 ml/ animal and day
- Acclimation period: at least 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 30 - 70
- Air changes (per hr): housing in fully air-conditioned rooms
- Photoperiod (hrs dark / hrs light): 12 h/12 h
Vehicle:
unchanged (no vehicle)
Controls:
other: the untreated left eye of each animal served as control
Amount / concentration applied:
An amount of 0.1 mL test material was applied into the conjunctival sac of the right eye of each animal.
Duration of treatment / exposure:
Not applicable as the test substance was not washed out.
Observation period (in vivo):
8 days
Number of animals or in vitro replicates:
Three animals were used, one male and 2 females.
Details on study design:
- Each animal received a single instillation of 0.1 mL unchanged test substance in the conjunctival sac of the right eye; the treated eye was not washed;
- Readings of the eyes were done after 1h, 24h, 48h, 72h and 8 days following application;
- Scoring of the eye findings was based on Draize (1959); calculation of the means was done according to the 83/467/EEC criteria (July 29th 1983);
- For calculation of the mean score values the time points 24h, 48h and 72h were considered;
- The animals further were observed for symptoms of toxicity and were sacrificed for necropsy at study ending.
Irritation parameter:
cornea opacity score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Irritation parameter:
cornea opacity score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Irritation parameter:
cornea opacity score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Irritation parameter:
conjunctivae score
Basis:
animal #1
Time point:
24/48/72 h
Score:
1.6
Max. score:
2
Reversibility:
fully reversible
Irritation parameter:
conjunctivae score
Basis:
animal #2
Time point:
24/48/72 h
Score:
1.6
Max. score:
2
Reversibility:
fully reversible
Irritation parameter:
conjunctivae score
Basis:
animal #3
Time point:
24/48/72 h
Score:
1.3
Max. score:
2
Reversibility:
fully reversible
Irritation parameter:
chemosis score
Basis:
animal #1
Time point:
24/48/72 h
Score:
1.3
Max. score:
2
Reversibility:
fully reversible
Irritation parameter:
chemosis score
Basis:
animal #2
Time point:
24/48/72 h
Score:
1
Max. score:
1
Reversibility:
fully reversible
Irritation parameter:
chemosis score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Max. score:
1
Reversibility:
fully reversible within: 24 hours
Remarks on result:
other: (chemosis graded 1 was reported for the reading time point 1 hour)
Irritation parameter:
iris score
Basis:
animal #1
Time point:
24/48/72 h
Score:
0
Irritation parameter:
iris score
Basis:
animal #2
Time point:
24/48/72 h
Score:
0
Irritation parameter:
iris score
Basis:
animal #3
Time point:
24/48/72 h
Score:
0
Irritant / corrosive response data:
- Neither corneal opacity nor iritis was seen, in none of the animals, at all reading time points.
- In the conjunctiva, well-defined redness was seen from time point 1h in all animals. At time point 72 h, redness turned to slight in all three cases, and after 8 days, redness had completely disappeared, indicating full reversibility.
- Slight to well-defined chemosis was seen in all 3 animals at time point 1h; in one case, chemosis disappeared within 24 hours. For the 2 remaining animals, chemosis turned to slight and full reversibilty was reported for the time point 8 day.
- Redness and swelling of the conjunctiva were accompanied by secretion in all three animals. In one female and the male, no more secretion was seen after time point 72 and 48 h, respectively. In the second female, secretion only was seen at time point 1 h.

According to the raw data, in the male animal (animal2), at time points 24 and 48 h, slight redness of the conjunctiva (graded 1) was seen in the left eye, which was the untreated one. The redness was no more seen at time point 72 h. Grading of the findings in the right eye were made in consideration of the slight irritation observed in the left eye.
Other effects:
No treatment-related effects were reported.
Interpretation of results:
GHS criteria not met
Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Study period:
1963
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Version / remarks:
(1981)
Deviations:
yes
Remarks:
[volume of 0.05 mL applied (OECD: volume of 0.1 mL; 2 animals were used (OECD: 3); observation period was 8 days (OECD: 21); examination using fluorescein (OECD: no use of fluorescein)]
Principles of method if other than guideline:
The test was conducted according to an internal BASF test method, which in principle was similar to OECD 405.
BASF-TEST:
Before OECD guideline 405 was established, eye irritation was tested using an internal method. White Vienna rabbits were used. Usually approximately 50 µl of the test substance were applied to the conjunctival sac of one eye of each of 2 animals. The non- or saline- treated eye served as control. In studies with solids, talcum powder was used as control. The animals were observed several times on the treatment day and up to 8 days afterwards, and findings were recorded on working days.
The eyes were not washed out after 24 h as specified in OECD Guideline 405, which could be critical for solids which thus remained on the cornea for several days, causing mechanical damage. Probably, this would have been less severe if it had been washed out after 1 day.
GLP compliance:
no
Remarks:
GLP was not compulsory at the time the study was conducted
Species:
rabbit
Strain:
Vienna White
Details on test animals or tissues and environmental conditions:
- Source: not specified
- Sex: one male and one female
- Weight at test initiation: 2 kg/animal
Vehicle:
unchanged (no vehicle)
Controls:
other: the untreated eye of each animal served as control
Amount / concentration applied:
ca. 0.05 mL of test material was instilled in the conjunctival sac of the right eye of each animal
Duration of treatment / exposure:
Not applicable as the test substance was not washed out. 
Observation period (in vivo):
8 days
Number of animals or in vitro replicates:
Two animals were used
Details on study design:
- Following application, the animals were examined for corneal changes, iris effects and conjunctival reaction at reading time points 1, 24 and 48 hrs, and at day 8;
- The eye findings, which had been originally scored according to a BASF scoring system in the raw data, were re-evaluated following conversion into Draize scores.
Irritation parameter:
cornea opacity score
Basis:
animal #1
Time point:
24/48 h
Score:
0.7
Reversibility:
fully reversible within: less than 8 days
Irritation parameter:
cornea opacity score
Basis:
animal #2
Time point:
24/48 h
Score:
0
Irritation parameter:
iris score
Basis:
animal #1
Time point:
24/48 h
Score:
0
Irritation parameter:
iris score
Basis:
animal #2
Time point:
24/48 h
Score:
0
Irritation parameter:
conjunctivae score
Basis:
animal #1
Time point:
24/48 h
Score:
1
Reversibility:
fully reversible within: less than 8 days
Irritation parameter:
conjunctivae score
Basis:
animal #2
Time point:
24/48 h
Score:
1
Reversibility:
fully reversible within: less than 8 days
Irritation parameter:
chemosis score
Basis:
animal #1
Time point:
24/48 h
Score:
0.5
Reversibility:
fully reversible within: less than 8 days
Irritant / corrosive response data:
- Corneal opacity was seen in one of the two treated animals;
- slight to distinct conjunctival redness and slight chemosis were reported for both animals;
- All findings were reversible within less than 8 days.
Other effects:
No other effects were reported
Interpretation of results:
GHS criteria not met
Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
test procedure in accordance with national standard methods with acceptable restrictions
Qualifier:
according to guideline
Guideline:
other: OECD Guideline from 1981 (no further information)
GLP compliance:
yes
Species:
rabbit
Strain:
New Zealand White
Details on test animals or tissues and environmental conditions:
TEST ANIMALS
- Source: Hazleton-Dutschland Inc. (Denver,PA)
- Age at study initiation: ca. 12-18 weeks
- Weight at study initiation: 2-3 kg
- Housing: individually in houses with wire floor
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-23
- Humidity (%): 57-66%
- Photoperiod (hrs dark / hrs light): 12h /12h

Vehicle:
unchanged (no vehicle)
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.1 mL
Observation period (in vivo):
readings after 1 h, 24 h, 48 h, 72 h and at days 7 and 10
Number of animals or in vitro replicates:
3
Irritation parameter:
maximum mean total score (MMTS)
Remarks:
washed eyes
Basis:
mean
Time point:
24 h
Score:
10.3
Max. score:
110
Reversibility:
fully reversible within: 10 days
Irritation parameter:
maximum mean total score (MMTS)
Remarks:
washed eyes
Basis:
mean
Time point:
48 h
Score:
9.3
Max. score:
110
Reversibility:
fully reversible within: 10 days
Irritation parameter:
maximum mean total score (MMTS)
Remarks:
washed eyes
Basis:
mean
Time point:
72 h
Score:
4.7
Max. score:
110
Reversibility:
fully reversible within: 10 days
Irritation parameter:
maximum mean total score (MMTS)
Remarks:
unwashed eyes
Basis:
mean
Time point:
24 h
Score:
7
Max. score:
110
Reversibility:
fully reversible within: 10 days
Irritation parameter:
maximum mean total score (MMTS)
Remarks:
unwashed eyes
Basis:
mean
Time point:
48 h
Score:
8.3
Max. score:
110
Reversibility:
fully reversible within: 10 days
Irritation parameter:
maximum mean total score (MMTS)
Basis:
mean
Time point:
72 h
Score:
5.3
Max. score:
110
Reversibility:
fully reversible within: 10 days
Interpretation of results:
GHS criteria not met
Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
adverse effect observed (irritating)

Additional information

Skin irritation

Glyoxal (40 % aqueous solution) was shown to be not corrosive in the in vitro EpiDermTM Corrosivity-Test (BASF 61H0150/022020;2002). Following application of the test material to the intact skin of White Vienna rabbits under semi-occlusive conditions, no signs of skin irritation were noticed. Glyoxal 40% aqueous solution tested according to OECD TG 404 was therefore not irritating to the skin of rabbits (BASF 85/16; 1985). In earlier studies, Glyoxal (40%) applied to the intact skin of White Vienna rabbits for 1, 5 and 15 minutes as well as for 20 hours under occlusive conditions resulted in skin findings (erythema, edema, necrosis) which partly lasted for 8 days, thus indicating slight to severe irritation (BASF AG XIII/258 and BASF AG XX/162-163). Moreover, in an acute dermal toxicity study conducted with Wistar rats (see acute toxicity) where Glyoxal 40% was applied at a dose of 1.57 mL/kg bw to the skin for 24 hours and under semi-occlusive conditions, skin examination revealed erythema in both males and females on day 1 following treatment.

Eye irritation

Following single instillation of unchanged Glyoxal (40 % aqueous solution; 0.1 mL) into the conjunctival sac of the right eye of White Vienna rabbits as recommended by OECD TG 405, redness and eye secretion were reported for all three test animals. All findings were reversible as they completely disappeared within 8 days. Despite of the slight signs of irritation reported above Glyoxal 40% was not considered to be an eye irritant according to EU classification criteria (BASF 85/16; 1985). In an earlier study on the rabbit eye (BASF AG XIII/258; 1963), the instillation of Glyoxal (40 % aqueous solution; 0.05 mL) into the conjunctival sac caused slight to distinct conjunctival redness and slight chemosis. Corneal opacity was seen in one of the two treated animals. All findings were reversible within less than 8 days. In a comparative study between pure glyoxal (40 % aqueous solution) and crude Glyoxal (40 % aqueous solution of technical grade) and their effects on the rabbit eye (BASF AG XX/162-163; 1970), the instillation of 0.05 mL unchanged test material into the conjunctival sac caused a clear reddening and very strong inflammation on the conjunctiva. After instillation of pure glyoxal, a slight corneal opacity was observed up to reading time point 72 hours, thereafter, corneal opacity was no longer observed. The technical grade Glyoxal induced cloudy to milky corneal opacity that still was evident on day 8.

In a further study, instillation of 0.1 mL of the test item (40%), followed by rinsing with warm water, resulted no corneal injury in any of the 6 eyes directly after instillation. There was iritis in 4 eyes as well as minor to moderate conjunctival irritation in 6 eyes after 24 h (with necrosis in 3). Conjunctival necrosis was apparent after 48 h. Eyes appeared normal after 10 days. In washed eyes: No corneal injury in any of 3 eyes, iritis in 2 eyes, minor to severe conjunctival irritation in 3 (with necrosis in one) was observed. Eyes appeared normal after 10 days (American Cynamid OTS0533535, 1988).

Summarizing, it can be retained that the more recent skin irritation study conducted according to OECD TG 404 showed that Glyoxal (40% aqueous solution) caused no irritation after a 4 hours exposure on the skin of rabbits under semi occlusive conditions. The more recent study for eye irritation, which was conducted according to OECD TG 405, revealed signs indicative of irritation to the eyes, but the calculated Draize scores were below the limits for classification of the test substance as irritant according to EU criteria. In contrast, older studies revealed that Glyoxal (40%) was irritating to both, the intact skin and the eye of rabbits, though the test conditions were more stringent when compared to OECD TG requirements.

 


Justification for classification or non-classification

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

The substance is already listed in Annex VI of Regulation (EC) No 1272/2008 and classified with skin and eye irritation Cat. 2 (H315 and H319:”Causes skin irritation; Causes serious eye irritation”).

The available experimental test data are reliable and suitable for the purpose of classification under Regulation (EC) No 1272/2008. Based on these information the test item is considered to be classified for skin and eye irritation Cat. 2 under Regulation (EC) No. 1272/2008, as amended for the tenth time in Regulation (EU) No 2017/776.