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Toxicological information

Eye irritation

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Administrative data

Endpoint:
eye irritation: in vivo
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
3 (not reliable)
Rationale for reliability incl. deficiencies:
significant methodological deficiencies
Remarks:
Significant methological deficencies: instilled volume insufficient (0.005 mL)
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reference
Endpoint:
skin irritation: in vivo
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Similar to guideline study
Reason / purpose:
reference to same study
Reason / purpose:
reference to same study
Reason / purpose:
reference to same study
Reason / purpose:
reference to same study
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 404 (Acute Dermal Irritation / Corrosion)
GLP compliance:
not specified
Species:
rabbit
Strain:
New Zealand White
Type of coverage:
occlusive
Preparation of test site:
clipped
Vehicle:
unchanged (no vehicle)
Controls:
not required
Amount / concentration applied:
TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 0.5 mL
Duration of treatment / exposure:
1) 4 hours and
2) 3 minutes
Observation period:
14 days
Number of animals:
6
Details on study design:
TEST SITE
- Area of exposure: no data
- % coverage: no data
- Type of wrap if used: gauze patch with impervious sheeting

REMOVAL OF TEST SUBSTANCE
- Washing (if done): excess material is removed after the 4-hr or 3-min contact period

SCORING SYSTEM: Table of Draize (as in OECD 404)
Irritation parameter:
erythema score
Basis:
mean
Time point:
other: 5 hr after skin contact
Score:
1.3
Max. score:
4
Reversibility:
not reversible
Remarks:
Skin necroses were seen at the 5-hr reading in 3 rabbits. Irreversible skin alterations were seen in all animals at 14 after 14 days post treatment.
Remarks on result:
other: 3-minute skin contact
Irritation parameter:
edema score
Basis:
mean
Remarks:
of 6 animals
Time point:
other: 5 hr after skin contact
Score:
2.5
Max. score:
4
Reversibility:
not reversible
Remarks on result:
other: 3-minute skin contact
Irritant / corrosive response data:
At the 5-hr skin examination and thereafter, skin necrosis was seen in most rabbits exposed for 3 minutes and all animals exposed for 4 hours. Full thickness necrosis was confirmed at termination. No reading was made within 1 hour after skin contact.

Skin reactions after 4-hr contact period (means of 6 animals); 0.5 mL dosed

Time post
skin contact

Erythema
(mean score)

Edema
(mean score)

Specific effects(selected effects))
N=necrosis
U = ulceration

5 hours

2.0

4.0

N (all animals)

1 day

2.5

4.0

N (all animals)

2 days

3.0

4.0

N (all animals)
U (1 animal)

3 days

2.8

4.0

N (all animals)
U (5 animals)

7 days

1.0

-

N (all animals)
U (5 animals)

10 days

0.3

-

N (all animals)
U (5 animals)

14 days

0.0

-

N (all animals)
U (5 animals)

 

Skin reactions after a 3-minute contact period (means of 6 animals); 0.5 mL dosed

 

Time post
skin contact

Erythema
(mean score)

Edema
(mean score)

Specific effects(selected effects)
N=necrosis
U = ulceration
D = desquamation

5 hours

1.3

2.5

N (3 animals)

1 day

2.3

3.8

N (3 animals)

2 days

2.2

3.0

N (4 animals)

3 days

0.0

2.3

N (4 animals)

7 days

0.0

0.0

N (5 animals)
D (5 animals)

10 days

0.0

0.0

N (5 animals)
D (5 animals)

14 days

0.0

0.0


D (5 animals)

 

Interpretation of results:
Category 1B (corrosive) based on GHS criteria
Conclusions:
2-methylbuytric acid caused full thickness skin necrosis in 5 animals after a 3-minute contact to the intact rabbit skin. Necrosis was already seen in 3 animals at the first reading at 5 hours after skin contact. The substance is at least a CAT1B skin corrosive; classification as a CAT 1A corrosive is also possible but cannot be judged because this would require a reading within one hour after the skin contact (Regulation (EC) No. 1272/2008).
Executive summary:

Skin irritating/corrosive properties of the test item were investigated in New Zealand rabbits in a study similar to OECD TG 404. Rabbits were exposed for 3 minutes or 4 hours toward 0.5 mL of the undiluted test item and observed for up to 14 days. Full thickness skin corrosion was observed in animal after 3 minutes or 4 hour exposure and was evident already at the first reading at 5 hours after the start of the exposure.

Reason / purpose:
reference to same study
Reference
Endpoint:
acute toxicity: dermal
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Reason / purpose:
reference to same study
Reason / purpose:
reference to same study
Reason / purpose:
reference to same study
Reason / purpose:
reference to same study
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 402 (Acute Dermal Toxicity)
GLP compliance:
not specified
Test type:
standard acute method
Limit test:
no
Species:
rabbit
Strain:
New Zealand White
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Weight at study initiation: between 2.0 and 3.0 kg
Type of coverage:
occlusive
Vehicle:
unchanged (no vehicle)
Details on dermal exposure:
TEST SITE
- Type of wrap if used: occlusive

REMOVAL OF TEST SUBSTANCE
- Washing: excess fluid removed
- Time after start of exposure: 24 hr

TEST MATERIAL
- Amount(s) applied (volume or weight with unit):
males: 0.5. 1.0, 2.0, 2.83, and 4.0 mL/kg bw
females: 0.5. 1.0, 1.41, 2.0, and 4.0 mL/kg bw
- Constant volume or concentration used: no
Duration of exposure:
24 hr
Doses:
males: 0.5. 1.0, 2.0, 2.83, and 4.0 mL/kg bw (i.e. 468, 936, 1872, 2649, 3744 mg/kg bw)
females: 0.5. 1.0, 1.41, 2.0, and 4.0 mL/kg bw (i.e. 468, 936, 1320, 1872, 3744 mg/kg bw)
No. of animals per sex per dose:
5
Control animals:
not specified
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: on days 0 (prior to treatment), 7, and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, skin reactions at one hour, 7 days and 14 days after contact period.
Statistics:
LD50 value was calculated using teh moving average method (Thompson, 1947; Weil, 1983)
Key result
Sex:
male
Dose descriptor:
LD50
Effect level:
2 228 mg/kg bw
Based on:
test mat.
Remarks on result:
other: The applied volume was converted to mg/kg bw using a density of 0.936 kg/L
Key result
Sex:
female
Dose descriptor:
LD50
Effect level:
1 367 mg/kg bw
Based on:
test mat.
Remarks on result:
other: The applied volume was converted to mg/kg bw using a density of 0.936 kg/L
Mortality:
Moast deaths occurred at 1.5 hours to one day; one female died at 3 days. A few affected survivors recovered after one to three days.

Males: all animals (5/5) of the two highest dose groups (4 and 2.83 mL/kg bw) died, no mortalities occurred at lower dose levels
Females: all animals (5/5) of the two highes dose groups (4 and 2 mL/kg bw) died, two animals (2/5) of the mid dose group (1.41 mL/kg bw) died, no animals died at the lower dose groups
Clinical signs:
Local efefcts: erythema, edema, necrosis, desquamation, alopecia, ulceratins, scabs.
Sluggishness, unsteady gait, prostration, red discharge on the perinasal and perianal fur were among the signs of toxicity noted.
Body weight:
Males: body weight gain in groups at 0.5 and 1.0 mL/kg bw; no body weight gain at 2.0 mL/kg.
Females: body weight gain in groups at 0.5 and 1.0 mL/kg bw; no body weightgain at 1.41 mL/kg bw. Complete mortality at higher dose levels.
Gross pathology:
Findings included a few discoloured lungs; red to tan livers; grey stomachs; stomachs and/or intestines with black foci; small instetsines fileld with red liquid (in 2); dark purple or red kidneys; dark red thymuses; and bladders filled with blood.
Interpretation of results:
Category 4 based on GHS criteria
Conclusions:
The acute dermal LD50 was 2228 mg/kg bw in male and 1367 mg/kg bw in female rabbits.Changes noted in internal organs suggest dermal absorption of the acid and irritation/corrosion of the organs.
Executive summary:

Dermal toxicity was investigated in a study similar to OECD TG 405. Male and female white rabbits (n=5 per sex per dose) were exposed for 24 h against different doses of test substance up to 4 mL/kg bw (3744 mg/kg bw by calculation on basis of substance density of 0.936 kg/L). Exposed animals showed local effects like erythema, edema, necrosis, desquamation, alopecia, ulceratins, and scabs. Clinical sign in treated animals were sluggishness, unsteady gait, prostration, red discharge on the perinasal and perianal fur. Body weight did not increase in animals which received more than 1 mL/kg bw. At necropsy discoloured lungs, red to tan livers, grey stomachs, stomachs and/or intestines with black foci, small instetsines fileld with red liquid (in 2), dark purple or red kidneys, dark red thymuses, and bladders filled with blood were observed. The acute dermal LD50 was 2228 mg/kg bw in male and 1367 mg/kg bw in female rabbits.

Reason / purpose:
reference to same study
Reference
Endpoint:
acute toxicity: inhalation
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
Principles of method if other than guideline:
Inhalation Risk Test
GLP compliance:
not specified
Test type:
fixed concentration procedure
Limit test:
yes
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Weight at study initiation: 200 - 300 g
Route of administration:
inhalation: vapour
Type of inhalation exposure:
whole body
Vehicle:
air
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: animal chmaber
- Exposure chamber volume: 100 to 152 L
- Method of holding animals in test chamber: in cage
- Source and rate of air: air in the exposure chamber
- System of generating atmosphere: 100 g of the test material was placed in the sealed exposure chamber for approx. 18 hours. A mixing fan periodically agitated the chamber atmosphere to aid in distribution of the vapour. Oxgen was added, as needed, to maintain approx. 20% of oxygen.


Analytical verification of test atmosphere concentrations:
not specified
Duration of exposure:
6 h
Concentrations:
saturation
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: on days 0 (prior to treatment), 7, and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight
Statistics:
none
Key result
Sex:
male/female
Dose descriptor:
LC0
Effect level:
8 375 mg/m³ air (nominal)
Based on:
test mat.
Exp. duration:
6 h
Remarks on result:
other: There were no signs of toxicity and no gross lesions at necropsy.
Mortality:
No death during exposure or thereafter
Clinical signs:
None noted
Body weight:
Increase in males from 280 g on day 0 to 339 g on day 14. No significant body weight gain in females (237 g before treatment, 244 g at day 14 (all values means).
Gross pathology:
No gross lesions noted
Interpretation of results:
GHS criteria not met
Conclusions:
Male and female rats (5 per sex) survived a 6-hour whole body exposure to a saturated vapour atmosphere. There were no deaths within the 14-day observation period. There were no clinical signs of toxicity at any time, or gross lesions at terminal sacrifice. According to EC/1272/2008 table 3.1.1 the substance is not acutely toxic after inhalation.
Executive summary:

Male and female rats (5 per sex) survived a 6-hour whole body exposure to a saturated vapour atmosphere. There were no deaths within the 14-day observation period. There were no clinical signs of toxicity at any time, or gross lesions at terminal sacrifice.

Reason / purpose:
reference to same study
Reference
Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
comparable to guideline study with acceptable restrictions
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
GLP compliance:
not specified
Limit test:
no
Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Weight at study initiation: 200 - 300 g
- Fasting period before study: overnight
- Diet: standard lab diet ad libitum
- Water: ad libitum
Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Details on oral exposure:
MAXIMUM DOSE VOLUME APPLIED: 4 mL/kg bw
Doses:
males: 1.0, 2.0, 4.0 mL/kg bw
females: 0.25, 0.5, 1.0, 2.0, 4.0 mL/kg bw
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: on days 0 (prior to treatment), 7, and 14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight
Statistics:
LD50 value was calculated using the moving average method (Thompson, 1947; Weil, 1983)
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
1 750 mg/kg bw
Based on:
test mat.
Remarks on result:
other: Using a density of 0.936 kg/L, the calculated LD50 of 1.87 mL/kg bw is equivalent to 1750 mg/kg bw
Mortality:
Most deaths occurred at 1.5 to 2 days. However, three females died at 10 to 14 days. Survivors recovered at one to three days.

Males: 0/5, 3/5 and 5/5 of the low, middle and high dose group died
Females: 0/5, 0/5, 1/5, 2/5, 5/5 of the 0.25, 0.5, 1, 2, 4 mL/kg bw dose group died, respectively
Clinical signs:
Signs of toxicity included sluggishness, lacrimation, unkempt fur, kyphosis (in 2), prostration, a moribund appearance, diarrhea, red to brown discharge on perioral, perinasal and periurogenital fur.
Body weight:
Males: body weight gain at 1.0 mL/kg bw; bodyw eight reduced at 2.0 mL/kg bw
Females: no body weight gain at all dose levels
Gross pathology:
Dead animals: stomach abnormalities (discoloration, brown liquid or gas, gastric collapse); discoloure dlungs; brown to dark red livers, intstines, and kidneys.
Survivors: small stomachs and spleens; rough stomach surfaces, adhesion of the stomach to liver or spleen, enlarged and mottled red kidneys.
Interpretation of results:
Category 4 based on GHS criteria
Conclusions:
The LD50 was 1750 mg/kg bw in male and female rats. Necropsy findings in survivors revealed irritation/corrosion of the stomach and intestines.
Executive summary:

Oral toxicity was investigated in a study similar to OECD TG 401. Male and female rats (n=5 per sex per dose) were exposed against different doses of test substance up to 4 mL/kg bw (3744 mg/kg bw by calculation on basis of substance density of 0.936 kg/L). Exposed animals showed signs of toxicity including sluggishness, lacrimation, unkempt fur, kyphosis, prostration, a moribund appearance, diarrhea, red to brown discharge on perioral, perinasal and periurogenital fur. Female rats of all dose groups and male rats at doses >= 2 mL/kg bw did not gain body weight. The following findings were observed at necropsy of dead animals: stomach abnormalities (discoloration, brown liquid or gas, gastric collapse), discoloured lungs, brown to dark red livers, intstines, and kidneys. Necropsy of the surving animals revealed the following effects: small stomachs and spleens; rough stomach surfaces, adhesion of the stomach to liver or spleen, enlarged and mottled red kidneys.Using the moving average method an LD50 value of 1.87 mL/kg bw (corresponding to 1750 mg/kg bw) was calculated for male and female rats.

Data source

Reference
Reference Type:
other: TSCAT submission
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Deviations:
yes
Remarks:
insufficient test materila (0.005 mL)
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Details on test material:
- Name of test material (as cited in study report): 2-methylbutyric acid
- Analytical purity: 97.9%
- Impurities (identity and concentrations): valeric acid 1.8%; unidentified 0.3%
- Stability under test conditions: shell life > 6 months
- Storage condition of test material: room temperature

Test animals / tissue source

Strain:
New Zealand White

Test system

Vehicle:
unchanged (no vehicle)
Controls:
not required
Amount / concentration applied:
0.005 mL
Duration of treatment / exposure:
single dose
Observation period (in vivo):
21 days
Number of animals or in vitro replicates:
6
Details on study design:
SCORING SYSTEM: Darize (OECD 405)

Results and discussion

In vivo

Irritant / corrosive response data:
Instillation of 0.005 mL per eye resulted in moderate to severe corneal opacity in 6/6 animals. Iris was not affected and minor to severe conjunctival irritation developed in 6/6 rabbits. A purulent discharge developed after 48 hours in all animals, followed by necrosis of the nictating membrane in all animals. By day 21, 4/5 eyes appeared normal.

Applicant's summary and conclusion

Interpretation of results:
study cannot be used for classification
Remarks:
Migrated information
Conclusions:
Under the conditions of the test the substance caused severe eye damage including necrosis.