Tetrahydrofuran

Eye irritation

Administrative data

Endpoint:

eye irritation

Remarks:

other: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1971

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Information taken from a Company report from 1971, updated by original study author in 2010. Report contains some gaps in experimental conditions, but results are sufficient in detail for evaluation.

Data source

Reference

Reference 1

Reference Type:

other company data

Title:

Unnamed

Year:

1971

Report date:

1971

Reference 2

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: The Federal Hazardous Substances Act regulation 191.12 as amended September 17, 1964

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Tetrahydrofuran

EC Number:

203-726-8

EC Name:

Tetrahydrofuran

Cas Number:

109-99-9

Molecular formula:

C4H8O

IUPAC Name:

tetrahydrofuran

Details on test material:

- Name of test material (as cited in study report): Furan, tetrahydro-- Lot/batch No.: Haskell No. 7170

Test animals / tissue source

Species:

rabbit

Strain:

other: albino

Details on test animals or tissues and environmental conditions:

No information on environmental conditions provided.Animals used on this study were free of pre-existing corneal or conjunctivalinjury or irritation.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

not specified

Amount / concentration applied:

0.1 mL

Duration of treatment / exposure:

Single application, eyes unwashed

Observation period (in vivo):

Up to 14 days

Number of animals or in vitro replicates:

6

Details on study design:

An aliquot of 0.1 mL of H-7170 was introduced into the lower conjunctival sac of the right eye of each rabbit. The left eye of each rabbit was not treated with the test substance and served as a control. The treated and control eyes of all rabbits remained unwashed. Approximately 24, 48, and 72 hours, and 14 days after H-7170 was administered, the rabbits were examined for evidence of eye irritation. At each of these observation periods, eyes were examined using illumination and a hand-slit lamp and scored for ocular reactions according to the Draize Scale (Table 1). Control eyes were not scored. These untreated eyes were used for comparison and were considered "normal" relative to the treated eye. A biomicroscope was used to check for any positive iritic reactions and corneal effects at 14 days. The rabbits were weighed on the day of treatment, at 24 hours after instillation, and at the last ocular evaluation.

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

overall irritation score

Remarks:

Positive as defined under Section 191.12 of the Federal Hazardous Substances Act

Basis:

other:

Remarks on result:

other: 6/6 positive

Results 2

Irritation parameter:

other: Cornea

Basis:

other:

Reversibility:

not reversible

Remarks on result:

other: 6/6 animals, opacity

Results 3

Irritation parameter:

other: iris

Basis:

other:

Reversibility:

fully reversible within: 14 days

Remarks on result:

other: 6/6 animals, iritis

Results 4

Irritation parameter:

other: conjunctiva

Basis:

other:

Reversibility:

not specified

Remarks on result:

other: redness, 6/6 diffuse crimson redness; 2/6 swelling with lids about half closed; 3/6 swelling with partial eversion of lids

Results 5

Irritation parameter:

other: cornea

Basis:

other: irreversible corneal damage

Time point:

other: 14 days

Reversibility:

not reversible

Remarks on result:

other: 2/6 animals; readings of eyes made at 14 days with the use of a biomicroscope.

Irritant / corrosive response data:

Two of the six rabbit eyes exposed to tetrahydrofuran had severe, irreversible corneal damage.

Any other information on results incl. tables

Table 1. Individual animal scores for eye irritation.

	Animal No.	Corneal opacity	Iritis	Conjunctival Redness	Conjunctival Chemosis	Biomicroscope
24 hour	8222 8223 8224 8225 8226 8218	1 1 >1 2 1 1	1 1 1 1 1 1	2 2 2 2 2 2	2 1 2 3 3 2	- - - - - -
48 hour	8222 8223 8224 8225 8226 8218	1 1 2 >2 1 1	0 1 1 1 1 1	2 2 2 2 2 2	1 1 1 1 1 1	- - - - - -
72 hour	8222 8223 8224 8225 8226 8218	>1 2 2 >2 1 1	0 1 0 1 1 0	2 2 2 2 2 2	1 1 1 1 1 1	- - - - - -
14 days	8222 8223 8224 8225 8226 8218	3 1 2 1 1 3	0 0 0 0 0 0	1 0 1 0 0 1	0 0 0 0 0 0	Severe Mild Moderate Mild Mild Severe

Applicant's summary and conclusion

Interpretation of results:

Category 1 (irreversible effects on the eye) based on GHS criteria

Remarks:

Migrated information

Conclusions:

According to the definition of the eye test in the regulations of the Federal Hazardous Substances Act, tetrahydrofuran is classified as an eye irritant. Two of six rabbit eyes exposed to tetrahydrofuran had severe, irreversible corneal injury.

Executive summary:

Tetrahydrofuran caused moderate to severe eye irritation in rabbits, which were not reversible by 14 days. This is consistent with the CPT (1978) study, which only followed animals for 7 days, but found comparable lesions. It is proposed that THF be considered as a severe (Category 1) eye irritant under GHS.