Hydrogen fluoride

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

1980

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Reason / purpose for cross-reference:

reference to same study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

GLP compliance:

not specified

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

Male and female New Zealand white rabbits, weighing between 3 and 4 kg. Obtained from Hacking and Churchill Ltd, Huntingon, England. The rabbits were housed singly in standard cages and provided with standard food and water ad libitum.

Type of coverage:

occlusive

Preparation of test site:

shaved

Vehicle:

unchanged (no vehicle)

Controls:

no

Amount / concentration applied:

Approximately 0.5 ml of the substance was soaked onto small fabric patches (3x3cm in size)

Duration of treatment / exposure:

4 hours

Observation period:

7 days

Number of animals:

6

Details on study design:

The flank of 6 rabbits was shaved using electric clippers, 24 hours later a small patch (3x3cm) soaked on 0.5ml of the test substance was applied to the skin. The patch was held in place for 4 hours with plasters. After exposure the patches were removed and the skin washed with water and dried. The rabbits were observed for 7 days. Assessments were made 2, 24, 48, 72 hours and 7 days after patch removal. Test sites were scored for erythema and eschar formation, and oedema formation according to the Draize system.

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: mean across all 5 time points

Score:

0

Max. score:

0

Remarks on result:

other: 0.13% HF

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: mean across all 5 time points

Score:

0

Max. score:

0

Remarks on result:

other: 1.06% HF

Irritant / corrosive response data:

All rabbits were assigned a score of 0 for erthythema/eschar formation and oedema formation at all time points following 4 hours dermal exposure to 0.13% and 1.06% HF.

Other effects:

No other effects were found.

No further information.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: not specified

Conclusions:

0.13% and 1.06% hydrofluoric acid is not irritating to the intact skin of rabbits.

Executive summary:

The potential skin irritant effect of hydrofluoric acid (HF) was assessed in New Zealand White rabbits. 0.13% or 1.06% aqueous solutions of HF were applied to the intact, shaved flank skin of the rabbits. The skin was shaved 24 hours prior to test substance application. A small fabric patch was soaked in 0.5 ml of HF, applied to the skin and fixed in place for 4 hours. After removal the skin was washed and dried. The test sites were assessed for erythema and eschar formation and oedema formation, according to the Draize scoring system, at 2, 24, 48, 72 hours and 7 days after patch removal. No effects on substance adminsitration were seen, therefore 0.13% and 1.06% hydrofluoric acid is not irritating to the intact skin of rabbits.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1980

Report date:

1980

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Hydrogen fluoride

EC Number:

231-634-8

EC Name:

Hydrogen fluoride

Cas Number:

7664-39-3

Molecular formula:

FH

IUPAC Name:

hydrogen fluoride

Details on test material:

Flußsäure (hydrofluoric acid). In a 1.06 or 0.13% solution

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

Male and female New Zealand white rabbits, weighing between 3 and 4 kg. Obtained from Hacking and Churchill Ltd, Huntingon, England. The rabbits were housed singly in standard cages and provided with standard food and water ad libitum.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

yes, concurrent no treatment

Amount / concentration applied:

100 µl was administered into the conjunctival sac of the healthy eyes of 3 rabbits (test substance was administered to one eye per rabbit).

Duration of treatment / exposure:

The test substance was administered to the eye and was not washed out.

Observation period (in vivo):

7 days

Number of animals or in vitro replicates:

3 per HF concentration (6 in total)

Details on study design:

100 µl of the sample were applied to each of 3 rabbits in the conjunctival sac of a healthy eye. The rabbits were observed for 7 days. The other eye served as the untreated control. The treated eye was not washed out. The eyes were examined after one hour and after 24, 48 and 72 hours, and after 6 and 7 days. The cornea, iris, and conjunctiva (redness, swelling and ulceration) were scored according to the USA Fed. Reg. guidelines (1972).

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 1 hour

Score:

0

Max. score:

0

Remarks on result:

other: 0.13% HF

Results 2

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 1 hour

Score:

0

Max. score:

0

Remarks on result:

other: 0.13% HF

Results 3

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 1 hour

Score:

0.2

Max. score:

1

Remarks on result:

other: 0.13% HF

Results 4

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 1 hour

Score:

1

Max. score:

1

Reversibility:

not fully reversible within: 7 d

Remarks on result:

other: 1.06% HF

Results 5

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 1 hour

Score:

1.3

Max. score:

2

Reversibility:

not fully reversible within: 7 d

Remarks on result:

other: 1.06% HF

Results 6

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 1 hour

Score:

1.3

Max. score:

2

Reversibility:

not fully reversible within: 7 d

Remarks on result:

other: 1.06% HF

Irritant / corrosive response data:

At 0.13% two out of three rabbits showed a slightly marked, rapidly reversible conjunctival reaction (slight redness) (Table 1).
At 1.06% the substance caused a mild to moderate swelling, in 2 out of 3 animals the effect was longer lasting and the iris was slightly swollen and reddened. In 2 out of 3 animals the cornea was clouded and in 1 animal remained clouded for the entire observation period (Table 2).

Other effects:

No other effects reported

Any other information on results incl. tables

Table 1. Scores assigned to rabbits in the 0.13% HF group

Animal	Area	Time since application of substance
		1 h	24 h	2 d	3 d	6 d	7 d
1	Cornea	0	0	0	0	0	0
	Iris	0	0	0	0	0	0
	CR	1	0	0	0	0	0
	CS	0	0	0	0	0	0
	CU	0	0	0	0	0	0
2	Cornea	0	0	0	0	0	0
	Iris	0	0	0	0	0	0
	CR	1	0	0	0	0	0
	CS	0	0	0	0	0	0
	CU	0	0	0	0	0	0
3	Cornea	0	0	0	0	0	0
	Iris	0	0	0	0	0	0
	CR	0	0	0	0	0	0
	CS	0	0	0	0	0	0
	CU	0	0	0	0	0	0

 CR = Conjunctival redness

CS = Conjunctival swelling

CU = Conjunctival ulceration

Table 2. Scores assigned to rabbits in the 1.06% HF group.

Animal	Area	Time since application of substance
		1 h	24 h	2 d	3 d	6 d	7 d
1	Cornea	1	1	1	1	1	1
	Iris	2	1	1	1	1	1
	CR	2	2	2	2	2	2
	CS	2	2	1	1	1	1
	CU	0	0	0	0	0	0
2	Cornea	1	1	1	1	0	0
	Iris	1	1	1	1	0	0
	CR	2	2	1	1	1	1
	CS	2	1	1	1	0	0
	CU	0	0	0	0	0	0
3	Cornea	1	0	0	0	0	0
	Iris	1	0	0	0	0	0
	CR	2	2	1	1	1	1
	CS	2	1	1	1	0	0
	CU	0	0	0	0	0	0

 CR = Conjunctival redness

CS = Conjunctival swelling

CU = Conjunctival ulceration

Applicant's summary and conclusion

Interpretation of results:

moderately irritating

Remarks:

Migrated information Criteria used for interpretation of results: US CPSC / US FDA

Conclusions:

1% hydrofluoric acid is moderately irritating to the eyes of rabbits, with a risk of causing corneal clouding.

Executive summary:

The potential eye irritant effects of hydrofluoric acid were determined. Aqueous solutions of 0.13% and 1.06% were tested. The acid was added into the conjunctival sac of the healthy eyes of 3 rabbits, the other eye served as the untreated control. The test substance was not washed out after application. The eyes were assessed for irritation of the cornea, iris and conjunctiva according to the USA Fed. Reg. (1972). The 0.13% solution was not a primary irritant to the eye. The 1.06% solution was regarded as moderately irritating, with a risk of corneal clouding.