2-Pentanone, O,O',O''-(ethenylsilylidyne)trioxime

Endpoint summary

Description of key information

In the skin irritation study, no irritation or corrosion were observed.  In the eye irritation study, no corrosion was observed but ocular, iridial, and/or conjunctival irritation was observed in all rabbits.

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:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline study conducted under GLP

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Animals for this study were selected from a stock supply of healthy adult rabbits of the New Zealand White strain. They were in the weight range of 2.69 to 3.62 kg and 30 or 35 weeks of age, prior to treatment (Day 1). All rabbits were acclimatised to the experimental environment for a period of at least 12 or 13 weeks prior to the start of the study.
The rabbits were housed individually in plastic cages with perforated floors. Each rabbit was offered 125 g of a standard laboratory rabbit diet per day; drinking water was provided ad libitum. The batch of diet used for the study was analysed for nutrients, possible contaminants and micro-organisms likely to be present in the diet and which, if in excess of specified amounts, might have an undesirable effect on the test system. The animals were
given a dietary supplement of hay.
During the acclimatisation and study period the animals were given small soft white untreated wood blocks for environmental enrichment.
Results of routine physical and chemical examination of drinking water, as conducted by the supplier are made available to Huntingdon Life Sciences Limited.
Animal room environmental controls were set to maintain temperature within the range 16 to 20°C, and relative humidity within 40 to 70%. These environmental parameters were recorded and the permanent record archived with other departmental raw data. Lighting was controlled by means of a time switch to give 12 hours of artificial light (06:00 to 18:00 GMT) in each 24 hour period.

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.5 mL as supplied

Duration of treatment / exposure:

4 hours

Observation period:

7 or 9 days

Number of animals:

3 rabbits

Details on study design:

On the day before application of the test substance, hair was removed with clippers from the dorso-lumbar region of each rabbit exposing an appropriate sized area of skin.

Approximately 0.5 mL of the test substance was applied under a 2-ply 25 mm x 25 mm porous gauze pad secured with ‘blenderm’ surgical tape to intact skin sites on three animals. An additional site was similarly treated with the exception of test substance and acted as a control.

A single animal (number 4) received three exposures of three minutes, one or four hour’s duration in a step-wise manner and acted as a preliminary screen. In the absence of a severe effect on removal of the dressings the next exposure was initiated.

For exposures of one hour or more each treatment site was covered with cotton wool and "Tubigrip" elasticated bandage dressing for the duration of the exposure period. The animals were returned to their cages immediately after treatment. At the end of the exposure period the semi-occlusive dressing and gauze pad were removed and the treatment site was washed with lukewarm water (30-40°C) to remove any residual test substance. The treated area was blotted dry with absorbent paper.

Irritation parameter:

erythema score

Basis:

animal #4

Time point:

other: 24, 48, 72 hrs

Score:

1

Max. score:

1

Reversibility:

fully reversible

Irritation parameter:

erythema score

Basis:

animal #5

Time point:

other: 24, 48, 72 hrs

Score:

1

Max. score:

1

Reversibility:

fully reversible

Irritation parameter:

erythema score

Basis:

animal #6

Time point:

other: 24, 48, 72 hrs

Score:

1

Max. score:

1

Reversibility:

fully reversible

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

According to the criteria of the Globally Harmonised System and European Commission regulation 1272/2008 OS 1600 did not require any classification and labelling regarding skin irritation or corrosion.

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:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: OECD guideline study conducted under GLP

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Qualifier:

according to guideline

Guideline:

EU Method B.5 (Acute Toxicity: Eye Irritation / Corrosion)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

GLP compliance:

yes (incl. QA statement)

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Harlan, France
- Age at study initiation: at least 6 weeks
- Weight at study initiation: at least 1.0 kg
- Housing: individually
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: at least 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 21.4
- Humidity (%): 42 - 70
- Air changes (per hr): 16
- Photoperiod (hrs dark / hrs light):12 hrs

Vehicle:

unchanged (no vehicle)

Controls:

other: one eye was untreated and served as the control

Amount / concentration applied:

TEST MATERIAL
- Amount(s) applied: 0.1 ml
- Concentration : 100%

Duration of treatment / exposure:

lids held together for 1 sec

Observation period (in vivo):

24, 48, and 72 hour, 7 days, and 14 days after exposure

Number of animals or in vitro replicates:

3

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing (if done): not done


SCORING SYSTEM: Draize


TOOL USED TO ASSESS SCORE: fluorescein

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 24, 47, and 72 hours

Score:

0.67

Max. score:

1

Reversibility:

fully reversible within: 7 days

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 24, 48, and 72 hour

Score:

0.5

Max. score:

0.7

Reversibility:

fully reversible within: 72 hours

Irritation parameter:

conjunctivae score

Remarks:

redness

Basis:

mean

Time point:

other: 24, 48, and 72 hr

Score:

1.67

Max. score:

2.3

Reversibility:

fully reversible within: 14 days

Irritation parameter:

conjunctivae score

Remarks:

chemosis

Basis:

mean

Time point:

other: 24, 48, and 72 hr

Score:

ca. 1

Max. score:

1.3

Reversibility:

fully reversible within: 7 days

Other effects:

No clinical signs of toxicity noted

Interpretation of results:

irritating

Remarks:

Migrated information Category A2 Criteria used for interpretation of results: OECD GHS

Conclusions:

MPKO is irritating to rabbit eyes

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Justification for selection of skin irritation / corrosion endpoint:
Data for OS-1600 was used as an analog for OS-2600. Like OS-1600, OS-2600 quickly hydrolyzes releasing the oximes and the silicon moieties which simultaneously cross link to other silicon atoms forming a silicone polymer. The relevant species in the case of both OS-1600 and OS-2600 is 2-PO. In this study, OS-1600 was not irritating to the skin of rabbits. According to the criteria of the Globally Harmonised System and European Commission regulation 1272/2008 OS-2600 did not require any classification and labelling regarding skin irritation or corrosion.

Justification for selection of eye irritation endpoint:
Only one study available

Effects on eye irritation: moderately irritating

Justification for classification or non-classification

Based on GHS criteria, OS1600 is category 2.