Fenitrothion

Endpoint summary

Description of key information

Guideline-compliant studies of skin corrosion/irritation and eye irritation in the rabbit are available for fenitrothion.

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

Study period:

9 December 2009 - 12 May 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

yes

Specific details on test material used for the study:

Fenitrothion TG
Reddish/yellow oily liquid
Lot No.: 070502
Purity: 95.1%

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Kitayama Labs, Japan
- Age at study initiation: 11 weeks
- Housing: Individual
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 14 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 5 January 2010 To: 8 January 2010

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

0.5 mL

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

3

Details on study design:

0.5 mL of the test material was applied to the clipped dorsal skin of three rabbits for 4 hours under semi-occlusive conditions. Exposure was terminated by washing the remaining test material from the application site with acetone. Local dermal reactions were scored at 24, 48 and 72 hours after removal of the dressing.

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:

no indication of irritation

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:

no indication of irritation

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:

no indication of irritation

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:

no indication of irritation

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:

no indication of irritation

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:

no indication of irritation

Irritant / corrosive response data:

There was no evidence of local dermal irritation at the application site in any rabbit at any time point.

Other effects:

There were no signs of toxicity.

Mean scores for irritation

	24h	48h	72h	Mean (24-72h)
Erythema	0.00	0.00	0.00	0.00
Oedema	0.00	0.00	0.00	0.00

Interpretation of results:

GHS criteria not met

Conclusions:

There was no evidence of local dermal irritation at the application site in any rabbit at any time point; fenitrothion does not therefore require classification for skin corrosion or skin irritation according to the CLP criteria.

Executive summary:

The skin irritation potential of fenitrothion was investigated in a rabbit study according to OECD 404. 0.5 mL fenitrothion was applied to the clipped dorsal skin of three rabbits for 4 hours under semi-occlusive conditions.  Exposure was terminated by washing the remaining test material from the application site.  Local dermal reactions were scored at 24, 48 and 72 hours after removal of the dressing. There was no evidence of local dermal irritation at the application site in any rabbit at any time point; fenitrothion does not therefore require classification for skin corrosion or skin irritation according to the CLP criteria.

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

Study period:

9 December 2009 - 12 May 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

yes

Specific details on test material used for the study:

Fenitrothion TG
Reddish/yellow oily liquid
Lot No.: 070502
Purity: 95.1%

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Kitayam Labs
- Age at study initiation: 11 weeks
- Housing: Individual
- Diet: ad libitum
- Water: ad libitum
- Acclimation period: 14 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20-24
- Humidity (%): 30-70
- Air changes (per hr): at least 10
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: From: 4 January 2010 To: 7 January 2010

Vehicle:

unchanged (no vehicle)

Controls:

not required

Amount / concentration applied:

0.1 mL

Duration of treatment / exposure:

Not applicable: the treated eyes were unwashed

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

3

Details on study design:

0.1 mL of the test material was instilled into one eye of three rabbits. Ocular reactions were scored at 11, 24, 48 and 72 hours.

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

2

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

3

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

3

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

3

Reversibility:

fully reversible within: 48 hours

Remarks on result:

probability of weak irritation

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24/48/72 h

Score:

0

Max. score:

4

Reversibility:

other: Not applicable

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0.33

Max. score:

4

Reversibility:

fully reversible within: 48 hours

Remarks on result:

probability of weak irritation

Irritant / corrosive response data:

Signs of irritation were limited to Grade 1 conjunctival erythema and Grade 1 chemosis in one rabbit at the 24-hour observation point. All reactions had resolved by 48 hours.

Summary of ocular reactions

	24h	48h	72h	Mean (24-72h)
Cornea	0.00	0.00	0.00	0.00
Iris	0.00	0.00	0.00	0.00
Erythema	0.33	0.00	0.00	0.11
Chemosis	0.33	0.00	0.00	0.11

Interpretation of results:

GHS criteria not met

Conclusions:

Signs of irritation were limited to Grade 1 conjunctival erythema and Grade 1 chemosis in one rabbit at the 24-hour observation point.  All reactions had resolved by 48 hours. The reactions are not sufficient to trigger classification for serious eye damage or serious eye irritation according to the CLP criteria.

Executive summary:

The eye irritation potential of fenitrothion was investigated in a rabbit study performed in compliance with OECD 405. 0.1 mL of the test material was instilled into one eye of three rabbits' ocular reactions were scored at 11, 24, 48 and 72 hours. Signs of irritation were limited to Grade 1 conjunctival erythema and Grade 1 chemosis in one rabbit at the 24-hour observation point.  All reactions had resolved by 48 hours. The reactions seen in this study are not sufficient to trigger classification for serious eye damage or serious eye irritation according to the CLP criteria.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

The skin irritation potential of fenitrothion was investigated in a rabbit study according to OECD 404. 0.5 mL fenitrothion was applied to the clipped dorsal skin of three rabbits for 4 hours under semi-occlusive conditions.  Exposure was terminated by washing the remaining test material from the application site.  Local dermal reactions were scored at 24, 48 and 72 hours after removal of the dressing. There was no evidence of local dermal irritation at the application site in any rabbit at any time point; fenitrothion does not therefore require classification for skin corrosion or skin irritation according to the CLP criteria.

The eye irritation potential of fenitrothion was investigated in a rabbit study performed in compliance with OECD 405. 0.1 mL of the test material was instilled into one eye of three rabbits' ocular reactions were scored at 11, 24, 48 and 72 hours. Signs of irritation were limited to Grade 1 conjunctival erythema and Grade 1 chemosis in one rabbit at the 24-hour observation point.  All reactions had resolved by 48 hours. The reactions seen in this study are not sufficient to trigger classification for serious eye damage or serious eye irritation according to the CLP criteria.

There are no studies of respiratory irritation; however the lack of skin and eye irritation and the absence of relevant signs in the acute inhalation toxicity study indicate that fenitrothion is unlikely to be a respiratory irritant.

Justification for classification or non-classification

Fenitrothion has a harmonised classification under CLP and is not classified as a skin or eye irritant. The results of the available studies are consistent with the harmonised classification; no change is therefore proposed.