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Description of key information

Testing for irritation of the skin and eye demonstrated that at worst, n-Butyronitrile was a sight irritant, which does not require classification.

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
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study was conducted pre-GLP and pre-guidelines, so the report is lacking in detail. However, it was conducted at a highly reputable laboratory and was done to the state of the art at that time.
Qualifier:
no guideline followed
Principles of method if other than guideline:
This study was conducted as part of the 1960 acute dermal toxicity test presented in section 7.2.3. Since the exposure period (24 hours) and the covering (occlusive) used in the dermal toxicity test was more stringent than that used in a traditional OECD 404 (4 hour exposure and semi-occlusive covering), this data can be considered to be a worst-case finding.
GLP compliance:
no
Species:
guinea pig
Strain:
not specified
Details on test animals or test system and environmental conditions:
None provided
Type of coverage:
occlusive
Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
The dose used was 0.1 - 20 cc/kg
Duration of treatment / exposure:
24 hours
Observation period:
14 days
Number of animals:
7 total
Details on study design:
Skin irritation was evaluated as part of an acute dermal toxicity test.
Irritation parameter:
other:
Time point:
other: 24 hours
Score:
> 0 - < 0
Remarks on result:
other: findings were not scored, but TCC requires a score value, so "0" was used
Irritant / corrosive response data:
The test article was called out as a slight skin irritant that is absorbed through the skin.
Interpretation of results:
slightly irritating
Remarks:
Migrated information Criteria used for interpretation of results: expert judgment
Conclusions:
The test article was called out as a slight skin irritant that is absorbed through the skin.
Executive summary:

Skin irritation testing was done as part of a previously cited acute dermal toxicity test. As such, the test subjects were exposed to the test article for 24 hours under occlusive conditions rather than the traditional 4 hours under semi-occlusive conditions. That makes these results a "worst case". The test article was called out as a slight skin irritant that is absorbed through the skin. Note that only qualitative scoring was done. Values in this summary were added as the only apparent way to pass the TCC tool, but no numerical scoring was used in the study.

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
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study was conducted pre-GLP and pre-guideline, so details in the report are lacking. However, the study was conducted at a highly reputable laboratory, and was done to the state of the art at the time.
Qualifier:
equivalent or similar to guideline
Guideline:
OECD Guideline 405 (Acute Eye Irritation / Corrosion)
Deviations:
not specified
Principles of method if other than guideline:
The study was conducted prior to OECD guidelines, but it follows the general layout of OECD 405.
GLP compliance:
no
Species:
rabbit
Strain:
not specified
Details on test animals or tissues and environmental conditions:
None given
Vehicle:
unchanged (no vehicle)
Controls:
no
Amount / concentration applied:
1 drop
Duration of treatment / exposure:
14 days
Observation period (in vivo):
14 days
Number of animals or in vitro replicates:
1
Details on study design:
One drop of test article was applied to the eyes of a single rabbit followed by a 14-day observation period
Irritation parameter:
other:
Time point:
other: 24 hours
Score:
> 0 - < 0
Reversibility:
not specified
Remarks on result:
other: No score was given but as TCC demands a value, dummy numbers were used.
Irritant / corrosive response data:
Eyes were held closed briefly. Slight erythema of conjunctiva. Normal at 1 hr and 24 hours, although there was slight staining of nictitating membrane with fluorescein. Normal at 14 days.
Interpretation of results:
slightly irritating
Remarks:
Migrated information Criteria used for interpretation of results: expert judgment
Conclusions:
The test article was minimally irritating.
Executive summary:

The test article was minimally irritating. Note that this study only used a qualitative grade. Numerical values were added as TCC required them, but such grades were not provided in the study.

Endpoint conclusion
Endpoint conclusion:
no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion
Endpoint conclusion:
no study available

Additional information

n-Butyronitrile was not irritating to the skin or eyes of rabbits.


Justification for selection of skin irritation / corrosion endpoint:
The key study was based on evaluation of the skin as part of an acute dermal toxicity study. As the conditions of this study (24 hour exposure under occluded conditions) are more stringent than a standard skin irritation study (4 hours under a semi-occlusive dressing), the results can be considered to be a "worst-case" evaluation.

Justification for selection of eye irritation endpoint:
The study, while dated, was conducted to the standards of the time at a highly reputable facility.

Effects on skin irritation/corrosion: slightly irritating

Effects on eye irritation: slightly irritating

Justification for classification or non-classification

The level of irritation for n-Butyronitrile did not reach the level required for classification as an irritant.

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