7-hydroxy-3-(4-methoxyphenyl)-4-benzopyrone

Endpoint summary

Description of key information

Skin irritation:

In a reliable GLP OECD Guideline 404 in vivo skin irritation study, 0.5 mg Formononetin was applied to the shaved skin of 3 New Zealand White rabbits for 4 hours. No evidence of skin irritation or corrosive effects were noted during the study. The primary irritation index obtained from the 1, 24, 48 and 72 hour observations was 0.0.Therefore, Formononetin was found to be non-irritating to the skin in rabbits.

Eye irritation:

In a reliable GLP OECD guideline 405 in vivo eye irritation study, 57.8 mg test material was instilled into the eyes of 3 New Zealand White rabbits. There were no positive effects observed during the study. No irritation was observed in any eyes at 72 hours. Therefore, Formononetin is considered to be non-irritating to eyes.

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:

6 February - 3 June 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2500 (Acute Dermal Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

- Lot No. of test material: 07-170-FIL-2/3
- Appearance: White powder
- Expiration date: May 2010
- Purity: 98.4%
- Storage condition of test material: Room temperature

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Nichols Rabbitry Inc., Lumberton, TX
- Age at study initiation: Approx. 13 weeks old
- Weight at study initiation: Males: 2.350 - 2.800 kg; Female: 2.325 kg
- Housing: Suspended, wire bottom, stainless steel cage; 1 animal per cage
- Diet: PMI Feeds Inc. Lab Rabbit Diet #5321; 8 oz daily
- Water: Municipal water supply available ad libitum from automatic water system
- Acclimation period: Not specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3°C
- Humidity (%): 30 - 70%
- Air changes (per hr): 10 - 12 air changes/ hour
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle

IN-LIFE DATES: From: 12 February 2008 To: 15 February 2008

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.50 mg of test substance (moistened with 0.5 mL water) was applied to the test site

VEHICLE
- Amount applied: Each dose of test substance was moistened with 0.5 mL of deionised water

Duration of treatment / exposure:

4 hours

Observation period:

72 hours

Number of animals:

2 males and 1 female

Details on study design:

TEST SITE
- Area of exposure: The test material was applied to the dorsal surface of the trunk and covered with a 4 ply, 2.5 x 2.5 cm surgical gauze patch.
- % coverage: An area was clipped of at least 8 x 8 cm
- Type of wrap: Each patch was secured in place with a strip of non-irritating adhesive tape. The entire trunk of each animal was loosely wrapped with a semi-permeable dressing (orthopaedic stockinette) which was secured on both edges with strips of tape.

REMOVAL OF TEST SUBSTANCE
- Washing: The test sites were gently washed with room temperature tap water and a clean cloth to remove as much residual test material as possible.
- Time after start of exposure: 4 hours

OBSERVATION TIME POINTS
The test sites were observed for erythema and edema formation and any other dermal defects or irritation at 1, 24, 48 and 72 hours after unwrap.

SCORING SYSTEM: Draize
- Method of calculation:

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

other: All animals

Time point:

24/48/72 h

Score:

0

Remarks on result:

no indication of irritation

Irritation parameter:

erythema score

Basis:

other: All animals

Time point:

24/48/72 h

Score:

0

Irritation parameter:

edema score

Basis:

other: All animals

Time point:

24/48/72 h

Score:

0

Irritant / corrosive response data:

Erythema and edema were not observed at any time throughout the study. No other signs of irritation were observed during the study.

Other effects:

- Other adverse local effects: None
- Other adverse systemic effects: None

- Actual temperature: 18 - 22°C

- Actual relative humidity: 41 - 84% (Humidity was outside of the protocol range but did not affect the study outcome)

Interpretation of results:

GHS criteria not met

Conclusions:

No evidence of skin irritation or corrosive effects were noted during the study. The primary irritation index obtained from the 1, 24, 48 and 72 hour observations was 0.0. Therefore, Formononetin is considered to be non-irritating to skin.

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:

6 February - 3 June 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.2400 (Acute Eye Irritation)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

- Lot No. of test material: 07-170-FIL-2/3
- Appearance: White powder
- Expiration date: May 2010
- Purity: 98.4%
- Storage condition of test material: Room temperature

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

TEST ANIMALS
- Source: Nichols Rabbitry Inc., Lumberton, TX
- Age at study initiation: Approx. 13 weeks old
- Weight at study initiation: Male: 2.7 kg; Females: 2.4 - 2.6 kg
- Housing: Suspended, wire bottom, stainless steel cage; 1 animal per cage
- Diet: PMI Feeds Inc. Lab Rabbit Diet #5321; 8 oz daily
- Water: Municipal water supply available ad libitum from automatic water system
- Acclimation period: Not specified

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 ± 3°C
- Humidity (%): 30 - 70%
- Air changes (per hr): 10 - 12 air changes/ hour
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle

IN-LIFE DATES: From: 11 February 2008 To: 14 February 2008

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.1 mL by volume equivalent to 57.8 mg of test material

Duration of treatment / exposure:

24 hours

Observation period (in vivo):

72 hours

Number of animals or in vitro replicates:

1 male and 2 females

Details on study design:

REMOVAL OF TEST SUBSTANCE
- Washing: All treated eyes were washed with room temperature deionised water for one minute immediately after recording the 24 hour observation.
- Time after start of exposure: 24 hours

OBSERVATIONS:
The treated eyes of all animals were examined without magnification under white room lighting provided by daylight-type fluorescent ceiling fixtures and (if needed) an additional source of white light affixed to the examination table or using a hand-held flashlight. The grades of ocular reaction were recorded at 1, 24, 48 and 72 hours after treatment. The corneas of all treated eyes were examined immediately after the 24 hour observation with a fluorescein sodium ophthalmic solution. Any of the corneas which exhibited fluorescein staining at the 24 hour observation were re-examined with the fluorescein sodium ophthalmic solution at each consecutive observation until fluorescein staining of the cornea no longer occurred.

SCORING SYSTEM: Draize

TOOL USED TO ASSESS SCORE: fluorescein sodium ophthalmic solution and a Finoff ocular transilluminator with cobalt blue filter

Irritation parameter:

cornea opacity score

Basis:

other: All animals

Time point:

24/48/72 h

Score:

0

Irritation parameter:

iris score

Basis:

other: All animals

Time point:

24/48/72 h

Score:

0

Irritation parameter:

chemosis score

Basis:

other: All animals

Time point:

24/48/72 h

Score:

0

Irritation parameter:

conjunctivae score

Basis:

animal #1

Remarks:

Rabbit No. 2300-M

Time point:

24 h

Score:

1

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #2

Remarks:

Rabbit No. 2295-F

Time point:

24 h

Score:

1

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

animal #3

Remarks:

Rabbit No.

Time point:

24/48 h

Score:

1

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #1

Time point:

24/48/72 h

Score:

0.33

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #2

Time point:

24/48/72 h

Score:

0.33

Reversibility:

fully reversible

Irritation parameter:

conjunctivae score

Basis:

mean

Remarks:

animal #3

Time point:

24/48/72 h

Score:

0.67

Reversibility:

fully reversible

Irritant / corrosive response data:

There were no positive effects observed during the study. No irritation was observed in any eyes at 72 hours.

Other effects:

- Other observations: Fluorescein staining did not occur in any of the eyes.

- Actual temperature: 18 - 22°C
- Actual relative humidity: 41 - 84% (Humidity was outside of the protocol range but did not affect the study outcome)

Table 1: Ocular reactions

	Rabbit No. 2300-M				Rabbit No. 2295-F				Rabbit No. 2297-F
	Hours after treatment				Hours after treatment				Hours after treatment
	1	24	48	72	1	24	48	72	1	24	48	72
I. Cornea
A. Opacity	0	0	0	0	+	0	0	0	+	0	0	0
B. Area	0	0	0	0	4	0	0	0	4	0	0	0
C. Fluorescein staining	-	0	-	-	-	0	-	-	-	0	-	-
D. Stippling	0	0	0	0	0	0	0	0	0	0	0	0
SCORE	0	0	0	0	0	0	0	0	0	0	0	0
II. Iris
A. Grade	0	0	0	0	0	0	0	0	0	0	0	0
SCORE	0	0	0	0	0	0	0	0	0	0	0	0
III. Conjunctivae
A. Redness	1	1	0	0	1t	1	0	0	1	1	1	0
B. Chemosis	0	0	0	0	0	0	0	0	0	0	0	0
C. Discharge	0	0	0	0	0	0	0	0	0	0	0	0
D. Necrosis or ulceration	0	0	0	0	0	0	0	0	0	0	0	0
SCORE	2	2	0	0	2	2	0	0	2	2	2	0
TOTAL SCORE	2	2	0	0	2	2	0	0	2	2	2	0

M – male

F – female

t – trace of test substance in eye

Duration of study: 72 hours

 

Table 2: Scores and score summary

Time after treatment	Rabbit Number			Average score
	2300-M	2295-F	2297-F
Hour 1	2	2	2	2.0
Hour 24	2	2	2	2.0
Hour 48	0	0	2	0.7
Hour 72	0	0	0	0.0
Maximum average irritation score:				2.0

 

Interpretation of results:

GHS criteria not met

Conclusions:

Formononetin is considered to be non-irritating to eyes.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

The in vivo skin and eye irritation studies performed in accordance with OECD Guidelines 404 and 405, respectively, show that Formononetin is not irritating. Therefore, in accordance with Regulation (EC) No. 1272/2008, Formononetin does not require classification as a skin or eye irritant.