2-Pyridinecarboxylic acid, 4-amino-3,6-dichloro-

Endpoint summary

Description of key information

SKIN
Not-irritating, rabbit (male/female), OECD 404, EU Method B.4, EPA OPPTS 870.2500, JMAFF (2000), Brooks (2001)
Not-irritating, rabbit (male), OEcD 404, EU MEthod B.4, EPA OPPTS 870.2500, JMAFF 2 -1 -4, Patel (2018)

EYES
Corrosive, rabbit (male/female), OECD 405, EPA OPPTS 870.2400, EU Method B.5, JMAFF (2000), Brooks (2001)

Minimal conjuctival reaction, fully reversible by 24 hours, rabbit (female), OECD 405, EPA OPPTS 870.2400, EU Method B.5, JMAFF 2 -1 -5, Patel (2018)

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Reference 1

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 June 2001 to 30 August 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: JMAFF Primary Dermal Irritation Study, 2000

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Purity: 94.5%

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Age at study initiation: 17 - 18 weeks
- Weight at study initiation: 2.50 - 2.57 kg
- Housing: animals were individually housed in stainless steel cages
- Diet: 5 ounces of diet per day
- Water: ad libitum
- Acclimation period: at least 2 weeks

ENVIRONMENTAL CONDITIONS
- Temperature: 19 ± 3 °C
- Humidity: 40 - 60 % (relative)
- Air changes: 12 - 15 air changes per hour
- Photoperiod: 12 hours of darkness / 12 hours of light (06:00 to 18:00)

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

unchanged (no vehicle)

Remarks:

the test material was moistened with 0.3 mL of 0.5 % aqueous methylcellulose

Controls:

no

Amount / concentration applied:

The day prior to study start, an area approximately 10 x 10 cm of the back of three New Zealand White rabbits was clipped free of fur. On day 1, a 0.5 g aliquot of the test material moistened with 0.3 mL of 0.5 % aqueous methylcellulose was applied to the back of each rabbit.

Duration of treatment / exposure:

4 hours

Observation period:

72 hours after test material removal.

Number of animals:

Three, one male and two females.

Details on study design:

TEST SITE
The test material was applied to the back of each rabbit and covered with a gauze patch (semi-occlusive dressing ~6 x 6 cm) with cotton backing. The gauze patch was held in place with an elastic jacket.

REMOVAL OF TEST SUBSTANCE
The jacket and patch were removed after four hours, and the back was wiped with a damp disposable towel to remove any residual test material.

SCORING SYSTEM
The application sites were graded for erythema and oedema within thirty minutes, and 24, 48, and 72 hours after test material removal. The grades for dermal lesions were assigned according to the Draize scoring system as follows:

> Erythema and eschar formation
0 = No erythema
1 = Very slight erythema (barely perceptible)
2 = Well-defined erythema (slight)
3 = Moderate to severe erythema
4 = Severe erythema (beet redness) to slight eschar formation (injuries in depth)

> Oedema formation
0 = No oedema
1 = Very slight oedema (barely perceptible)
2 = Slight oedema (edges of area well-defined by definite raising)
3 = Moderate oedema (edges raised approximately 1 mm)
4 = Severe oedema (raised more than 1 mm and extending beyond the area of exposure)

OTHER EXAMINATIONS
Animals were weighed on the day of treatment and at study termination.

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

edema score

Basis:

animal #2

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritation parameter:

edema score

Basis:

animal #3

Time point:

other: within 60 minutes, 24, 48 and 72 hours

Score:

0

Max. score:

4

Irritant / corrosive response data:

There were no signs of dermal irritation in any of the three rabbits during the study. The rabbits were removed from study 72 hours after unwrapping.

Other effects:

All rabbits gained body weight over the 72-hour period.

Interpretation of results:

GHS criteria not met

Conclusions:

There were no signs of dermal irritation in any of the three rabbits during the study.

Executive summary:

The skin irritation potential of the test material was investigated in a study which was conducted under GLP conditions and in accordance with the standardised guidelines OECD 404, EU Method B.4, EPA OPPTS 870.2500 and JMAFF (2000).

During the study aliquots of 0.5 g test material (moistened with 0.3 mL of 0.5 % aqueous methylcellulose) were applied to 1 male and 2 female New Zealand White rabbits for approximately 4 hours to the intact skin on the back of each rabbit. There were no signs of dermal irritation in any of the three rabbits during the study. The rabbits were removed from study 72 hours after unwrapping. All rabbits gained body weight over the 72-hour period.

Reference 2

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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

Qualifier:

according to guideline

Guideline:

other: JMAFF 2-1-4

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

TSN314667
Batch: ENBK-169021-016
Purity: 95.9%

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Sainath Agencies, Hyderabad
- Age at study initiation: 3.5 to 4.5 months
- Weight at study initiation: Minimum: 2.182 kg, Maximum: 2.428 kg
- Housing: Stainless steel, wire mesh rabbit cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 7-9 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 22 °C
- Humidity (%): 64 to 65%
- Air changes (per hr): Minimum 15 air changes/hour
- Photoperiod (hrs dark / hrs light): 12 h artificial light and 12 h darkness, light hours being 06:00 - 18:00 h.

Type of coverage:

semiocclusive

Preparation of test site:

clipped

Vehicle:

other: distilled water

Controls:

yes, concurrent no treatment

Amount / concentration applied:

500 mg

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

3

Details on study design:

TEST SITE
Approximately 24 hours prior to the treatment, hair from the dorsolumbar region at two contralateral sites of each rabbit was closely clipped using a clipper. Care was taken to ensure that the skin was not abraded while clipping. An area greater than 6 cm2 was clipped at each site. An amount of 500 mg of aminopyralid TGAI (moistened with 0.5 mL of distilled water) was applied evenly to one of the clipped sites of each rabbit and the other clipped site remained untreated. The latter served as the control site. The treated and the control sites were covered with gauze patches of approximately 6 cm2 (gauze rolled) which were not more than 8-ply and were secured at the margins by non-irritating tape (Medi tape 330 hypo-allergenic surgical tape) to ensure that the rabbits did not ingest the test item.

REMOVAL OF TEST SUBSTANCE
At the end of the 4-hour exposure period (day 0), any residual test item was removed with cotton soaked in distilled water.

OBSERVATION TIME POINTS
Skin reactions were observed at 1, 24, 48 and 72 hours post patch removal. The site of application was visually assessed and scored according to the Draize scale

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Irritation parameter:

erythema score

Basis:

animal #2

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Irritation parameter:

erythema score

Basis:

animal #3

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Irritation parameter:

erythema score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

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

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

Remarks on result:

no indication of irritation

Irritation parameter:

edema score

Basis:

animal #1

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

edema score

Basis:

animal #2

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

edema score

Basis:

animal #3

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

The individual animal average dermal irritation scores observed at 24, 48 and 72 hours post patch removal after aminopyralid TGAI application were, for each rabbit respectively: 0.00, 0.00, 0.00 for erythema, and 0.00, 0.00, 0.00 for oedema.

Interpretation of results:

GHS criteria not met

Conclusions:

Not classified as skin irritant

Executive summary:

In an acute dermal irritation study, three healthy adult male New Zealand White rabbits, (approximately 3.5-4.5 months old and weighing 2.182-2.428 kg at dosing) were dermally exposed to aminopyralid TGAI. An amount of 500 mg of aminopyralid TGAI (moistened with 0.5 mL distilled water) was applied to approximately 6 cm²area of intact skin, previously clipped free of hair. The contralateral skin site of each rabbit remained untreated and served as a control. The treated and control sites were covered with a semi-occlusive dressing (a gauze patch, secured at the margins by non-irritating tape) for a period of 4 hours, after which the residual test item was removed with cotton soaked in distilled water. A sequential testing strategy was adopted; initially one rabbit was tested with a single patch applied evenly to the skin for a period of 4 hours. Based on the observations at 24 hours post patch removal, two additional rabbits were tested simultaneously to confirm the irritation response. The skin reactions of each rabbit were observed at 1, 24, 48 and 72 hours post patch removal and scored according to the Draize scale, described in the OECD TG 404. General health condition (clinical signs and body weight) was also monitored until study termination.

 

Very slight erythema (score of 1) was observed in all three rabbits at 1 hour post patch removal.

At 24 hours post patch removal, the treated skin site of all three rabbits recovered completely and appeared normal until the end of the 72-hour observation period.

 

The control skin site of all rabbits was normal throughout the experimental period.

 

There were no signs of systemic toxicity, in any treated animal.

 

The mean dermal irritation scores at 24, 48 and 72 hours post patch removal for the three rabbits were 0.00, 0.00, 0.00 for erythema and 0.00, 0.00, 0.00 for oedema, respectively.

 

In conclusion, aminopyralid TGAI caused a minimal dermal reaction in all three animals, which was fully reversible by 24 hours post patch removal.

 

Based on the results of this study, an indication of the classification for aminopyralid TGAI is as follows:

 

Globally Harmonized System of Classification and

Labelling of Chemicals (GHS 2017)                           :    Not classified as skin irritant

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Link to relevant study records

Reference

Reference 1

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 June 2001 to 30 August 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Remarks:

Study conducted to GLP in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: JMAFF Primary Eye Irritation Study, 2000

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Purity: 94.5%

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Age at study initiation: 20 - 21 weeks
- Weight at study initiation: 2.7 - 2.8 kg
- Housing: animals were housed individually in stainless steel cages
- Diet: animals received 5 oz. per day
- Water: ad libitum
- Acclimation period: at least 2 weeks
- Other: The eyes of three adult New Zealand White rabbits were examined with 2 % aqueous fluorescein stain and established as being free of defects/irritation the day prior to the study.

ENVIRONMENTAL CONDITIONS
- Temperature: 19 ± 3 °C
- Humidity: 40 - 60 % (relative)
- Air changes: 12 - 15 air changes per hour
- Photoperiod: 12 hours of darkness / 12 hours of light (06:00 to 18:00)

Vehicle:

unchanged (no vehicle)

Controls:

other: The left eye of each rabbit remained untreated and served as a control.

Amount / concentration applied:

A 0.1 g aliquot of the test material in powder form was instilled into each of the treated eyes.

Duration of treatment / exposure:

The eyelid of each rabbit was held closed for approximately one second after dosing.

Observation period (in vivo):

1, 24, 48 and 72 hours and 7, 14, 21, 28, and 35 days post-instillation

Number of animals or in vitro replicates:

Three

Details on study design:

Test material was instilled into the conjunctival sac of the right eye of three rabbits.
The behaviour of each rabbit was observed immediately post-treatment for indications of pain or discomfort. An ocular anaesthetic was used for both eyes of one rabbit on days 2, 3, and 4.

SCORING SYSTEM:
Irritation was scored according to the Draize scale (below):
> Cornea
Opacity: degree of density (area most dense is taken for reading).
0 = No ulceration or opacity
1 = Scattered or diffuse areas of opacity (except for slight dulling of normal lustre), details of iris clearly visible
2 = Easily discernible translucent area, details of iris slightly obscured
3 = Nacreous area, no details of iris visible, size of pupil barely discernible
4 = Opaque cornea, iris not discernible through the opacity

> Conjunctivae
Redness: (refers to the most severe effect of palpebral and bulbar conjunctivae in comparison to the control eye)
0 = Blood vessels normal
1 = Some blood vessels definitely hyperaemic (injected)
2 = Diffuse crimson colour, individual vessels not easily discernible
3 = Diffuse beefy red
Chemosis: lids and/or nictating membranes
0 = No swelling
1 = Any swelling above normal (includes nictating membranes)
2 = Obvious swelling with partial eversion of lids.
3 = Swelling with lids about half closed
4 = Swelling with lids more than half closed
Discharge
0 = No discharge
1 = Any amount different from normal (does not include small amounts observed in inner canthus of normal animals)
2 = Discharge with moistening of the lids and hairs just adjacent to lids
3 = Discharge with moistening of the lids and hairs a considerable area around the eye

> Iris
0 = Normal
1 = Markedly deepened rugae, congestion, swelling, moderate circumcorneal hyperaemia or injection; any of these or combination of any thereof, iris still reacting to light (sluggish reaction is positive)
2 = No reaction to light, haemorrhage, gross destruction (any or of all these)

TOOL USED TO ASSESS SCORE:
Both eyes of the rabbits were examined with a binocular loupe and a white halogen light at approximately 1, 24, 48, and 72 hours and 7, 14, 21, 28, and 35 days post-instillation for conjunctival redness and chemosis, discharge, corneal opacity, and reddening of the iris. A cobalt blue light was used to assess the corneas of all rabbits following fluorescein stain application at various times during the study.

OTHER EXAMINATIONS
Rabbits were weighed on the day of treatment and study termination.

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

not fully reversible within: 35 days

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

24/48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 21 days

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

24 h

Score:

2

Max. score:

4

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

other: 48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 21 days

Irritation parameter:

iris score

Basis:

animal #1

Time point:

24 h

Score:

0

Max. score:

2

Irritation parameter:

iris score

Basis:

animal #1

Time point:

other: 48/72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 7 days

Irritation parameter:

iris score

Basis:

animal #2

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 14 days

Irritation parameter:

iris score

Basis:

animal #3

Time point:

24/48/72 h

Score:

1

Max. score:

2

Reversibility:

fully reversible within: 7 days

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

3

Max. score:

4

Reversibility:

not fully reversible within: 35 days

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

24 h

Score:

2

Max. score:

4

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

other: 48/72 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 21 days

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24 h

Score:

3

Max. score:

4

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

other: 48/72 h

Score:

2

Max. score:

4

Reversibility:

fully reversible within: 21 days

Irritant / corrosive response data:

One hour after dosing, all rabbits had slight conjunctival redness, moderate chemosis, and moderate discharge. Twenty-four hours after dosing, all rabbits had moderate to marked conjunctival redness, moderate chemosis, moderate to marked discharge, and slight corneal opacity. The two male rabbits also had slight irritation of the iris twenty-four hours after dosing. Forty-eight hours after dosing, all rabbits had moderate to marked conjunctival redness, slight to moderate chemosis, moderate to marked discharge, slight corneal opacity, and slight irritation of the iris. The ocular irritation slowly diminished over time. Corneal vascularisation was noted in all three animals starting on day 15 and continuing for one rabbit through day 36. Two rabbits had ocular irritation that continued through study termination.

Other effects:

All rabbits gained body weight over the duration of the study.

Table 1: Individual Animal Irritation Grades

Observation time after dosing	Animal no.	Redness	Conjunctival chemosis	Discharge	Corneal opacity	Reddening of iris
24 hours	01A3957	2	3	2	2	0
	01A3955	3	2	3	2	1
	01A3956	3	3	3	2	1
48 hours	01A3957	2	3	2	2	1
	01A3955	2	1	1	2	1
	01A3956	3	2	2	1	1
72 hours	01A3957	3	3	2	2	1
	01A3955	2	1	1	2	1
	01A3956	3	2	2	1	1

Irritation parameter	Time Point	Mean score	Max score	Reversibility
Corneal opacity score	24, 48, and 72 hours	1.78	4	Not fully reversible within 35 days
Iris score	24, 48, and 72 hours	0.89	2	Fully reversible within 14 days
Chemosis score	24, 48, and 72 hours	2.22	4	Not fully reversible within 35 days
Conjunctival redness	24, 48, and 72 hours	2.56	3	Not fully reversible within 35 days
Conjunctival discharge	24, 48, and 72 hours	2	3	Fully reversible within 28 days

Interpretation of results:

Category 1 (irreversible effects on the eye)

Conclusions:

Under the conditions of the study, the animals displayed moderate to marked signs of ocular irritation which lessened over time but effects on the cornea, conjunctiva and chemosis persisted to study termination 35 days post-instillation.

Executive summary:

The eye irritation potential of the test material was investigated in a study which was conducted under GLP conditions and in accordance with the standardised guidelines OECD 405, EPA OPPTS 870.2400, EU Method B.5 and JMAFF (2000).

During the study aliquots of 0.1 g of neat test material in powder form were placed into the conjunctival sac of the right eye of one female and two male New Zealand White rabbits. An ocular anaesthetic was used for both eyes of one rabbit on days 2, 3, and 4.

One hour after dosing, all rabbits had slight conjunctival redness, moderate chemosis, and moderate discharge. Twenty-four hours after dosing, all rabbits had moderate to marked conjunctival redness, moderate chemosis, moderate to marked discharge, and slight corneal opacity. The two male rabbits also had slight irritation of the iris twenty-four hours after dosing. Forty-eight hours after dosing, all rabbits had moderate to marked conjunctival redness, slight to moderate chemosis, moderate to marked discharge, slight corneal opacity, and slight irritation of the iris. The ocular irritation slowly diminished over time. Corneal vascularisation was noted in all three animals starting on day 15 and continuing for one rabbit through day 36. Two rabbits had ocular irritation that continued through study termination. All rabbits gained body weight over the duration of the study.

Reference 2

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:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: JMAFF 2-1-5

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

TSN314667
Batch: ENBK-169021-016
Purity: 95.9%

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Sainath Agencies, Hyderabad
- Age at study initiation: 3.5 to 4.5 months
- Weight at study initiation: Minimum: 2.371 kg, Maximum: 2.511 kg
- Housing: Stainless steel, wire mesh rabbit cages
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 8-10 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 19 to 22 °C
- Humidity (%): 64 to 65%
- Air changes (per hr): Minimum 15 air changes/hour
- Photoperiod (hrs dark / hrs light): 12 h artificial light and 12 h darkness, light hours being 06:00 - 18:00 h, except light was kept on at the time of the subcutaneous injection during night hours.

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

0.1 mL

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

3

Details on study design:

After aminopyralid TGAI application, the eyes of all rabbits were observed for presence or absence of test item in the conjunctival sac at 1 hour and for the signs of ocular irritation at 1, 24, 48 and 72 hours.

SCORING SYSTEM: The irritant responses were scored following the method described in the OECD test guideline 405

One or two drops of fluorescein stain was instilled into the eye (on the cornea) of all rabbits at 24 hours post test item application. The eyelids were closed for a few seconds. Excess of the fluorescein stain was then removed using 0.9% (w/v) normal saline and the eye was examined with the aid of ophthalmoscope through a cobalt blue filter. Any disruption of corneal epithelium damage would appear as green fluorescein staining.

Irritation parameter:

cornea opacity score

Basis:

animal #1

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #2

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

cornea opacity score

Basis:

animal #3

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #1

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

2

Remarks on result:

no indication of irritation

Irritation parameter:

iris score

Basis:

animal #2

Time point:

other: 1/24/48/72 h

Score:

0

Max. score:

2

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

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

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

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

3

Remarks on result:

no indication of irritation

Irritation parameter:

conjunctivae score

Basis:

animal #1

Time point:

other: 1 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 24 h

Irritation parameter:

conjunctivae score

Basis:

animal #2

Time point:

other: 1 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 24 h

Irritation parameter:

conjunctivae score

Basis:

animal #3

Time point:

other: 1 h

Score:

1

Max. score:

3

Reversibility:

fully reversible within: 24 h

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Irritation parameter:

chemosis score

Basis:

animal #2

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

other: 1 h

Score:

1

Max. score:

4

Reversibility:

fully reversible within: 24 h

Irritation parameter:

chemosis score

Basis:

animal #1

Time point:

24/48/72 h

Score:

0

Max. score:

4

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

Remarks on result:

no indication of irritation

Irritation parameter:

chemosis score

Basis:

animal #3

Time point:

24/48/72 h

Score:

0

Max. score:

4

Remarks on result:

no indication of irritation

Irritant / corrosive response data:

The individual animal average eye irritation scores observed at 24, 48 and 72 hours post aminopyralid TGAI application were:
0.00, 0.00, 0.00 for corneal opacity,
0.00, 0.00, 0.00 for iris,
0.00, 0.00, 0.00 for conjunctival redness,
0.00, 0.00, 0.00 for conjunctival chemosis.

Interpretation of results:

GHS criteria not met

Conclusions:

Not classified as an eye irritant

Executive summary:

In an acute eye irritation study, three healthy adult female New Zealand White rabbits (approximately 3.5-4.5 month old and weighing 2.371-2.511 kg at dosing) were treated with 0.1 mL of aminopyralid TGAI. The test item was instilled in the conjunctival sac of one eye and the contralateral eye remained untreated and served as a control. A sequential testing strategy was adopted: Initially one rabbit was tested. Based on the observations at 24 hours post instillation, two additional rabbits were tested simultaneously to confirm the irritation response. Neither immediate corrosion nor excessive irritation was observed nor the test item was visible in the conjunctival sac at 1 hour post application, therefore treated and untreated eyes were washed with 0.9% (w/v) normal saline at approximately 24 hours post instillation. Individual eye reactions were observed at 1, 24, 48 and 72 hours post instillation and scored according to the Draize scale described in the OECD guideline 405. General health conditions (clinical signs and body weight) was also monitored.

 

Conjunctival redness (score of 1) and conjunctival chemosis (score of 1) were evident at 1 hour in all rabbits; recovery occurred by 24 hours in all three rabbits. No corneal opacity, iritis and discharge reactions were observed in any of the rabbits throughout the experimental period. Examination with fluorescein dye and cobalt blue filter performed 24 hours post application revealed no disruption of the corneal epithelium layer in all three rabbits.

 

The control eye of all rabbits was normal throughout the experimental period.

 

There were no signs of systemic toxicity, in any treated animal.

 

The mean of the eye irritation scores observed at 24, 48 and 72 hours post instillation were 0.00, 0.00, 0.00 for corneal opacity, 0.00, 0.00, 0.00 for iris effects, 0.00, 0.00, 0.00 for conjunctival redness and 0.00, 0.00, 0.00 for conjunctival chemosis for the three rabbits, respectively.

 

In conclusion, aminopyralid TGAI caused a minimal conjunctival reaction, fully reversible by 24 hours post instillation.

 

Based on the results of this study, an indication of the classification for aminopyralid TGAI is as follows:

 

Globally Harmonized System of Classification and

Labelling of Chemicals (GHS 2017)                      :    Not classified as an eye irritant

 

Endpoint conclusion

Endpoint conclusion:

adverse effect observed (irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin

The skin irritation potential of the test material was investigated in a study which was conducted under GLP conditions and in accordance with the standardised guidelines OECD 404, EU Method B.4, EPA OPPTS 870.2500 and JMAFF (2000). The study was assigned a reliability score of 1 in line with the criteria of Klimisch et al. (1997).

During the study aliquots of 0.5 g test material (moistened with 0.3 mL of 0.5 % aqueous methylcellulose) were applied to 1 male and 2 female New Zealand White rabbits for approximately 4 hours to the intact skin on the back of each rabbit.

There were no signs of dermal irritation in any of the three rabbits during the study. The rabbits were removed from study 72 hours after unwrapping. All rabbits gained body weight over the 72-hour period.

A second study conducted under GLP conditions and in accordance with the standardised guidelines OECD 404, EU Method B.4, EPA OPPTS 870.2500 and JMAFF 2 -1 -4 in female rabbits confirmed that the test substance was not irritating to rabbit skin.

Eyes

The eye irritation potential of the test material was investigated in a study which was conducted under GLP conditions and in accordance with the standardised guidelines OECD 405, EPA OPPTS 870.2400, EU Method B.5 and JMAFF (2000). The study was assigned a reliability score of 1 in line with the criteria of Klimisch et al. (1997).

During the study aliquots of 0.1 g of neat test material in powder form were placed into the conjunctival sac of the right eye of one female and two male New Zealand White rabbits. An ocular anaesthetic was used for both eyes of one rabbit on days 2, 3, and 4.

One hour after dosing, all rabbits had slight conjunctival redness, moderate chemosis, and moderate discharge. Twenty-four hours after dosing, all rabbits had moderate to marked conjunctival redness, moderate chemosis, moderate to marked discharge, and slight corneal opacity. The two male rabbits also had slight irritation of the iris twenty-four hours after dosing. Forty-eight hours after dosing, all rabbits had moderate to marked conjunctival redness, slight to moderate chemosis, moderate to marked discharge, slight corneal opacity, and slight irritation of the iris. The ocular irritation slowly diminished over time. Corneal vascularisation was noted in all three animals starting on day 15 and continuing for one rabbit through day 36. Two rabbits had ocular irritation that continued through study termination. All rabbits gained body weight over the duration of the study.

A second study conducted under GLP conditions and in accordance with the standardised guidelines OECD 405, EPA OPPTS 870.2400, EU Method B.5 and JMAFF 2 -1 -5 revealed only minimal conjuctival reaction, fully reversible by 24 hours. According to this study the test substance was not irritating to rabbit eyes.

Justification for classification or non-classification

In accordance with the criteria for classification as defined in Annex I, Regulation (EC) No. 1272/2008, the substance does not require classification with respect to skin irritation but does require classification with respect to serious eye damage/eye irritation (category 1) and is assigned the hazard phrase H318: Causes serious eye damage.

In accordance with the criteria for classification as defined in Annex VI, Directive 67/548/EEC (DSD), the substance does not require classification with respect to skin irritation but does require classification with respect to eye irritation/ corrosion and is assigned the risk phrase R41: Risk of serious damage to eyes.