Aspartic acid

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Aspartic acid

EC Number:

200-291-6

EC Name:

Aspartic acid

Cas Number:

56-84-8

Molecular formula:

C4H7NO4

IUPAC Name:

aspartic acid

Details on test material:

Identity: L-Aspartic acid
Chemical name: L-Aspartic acid
Batch number: ASP 26111
Expiry: Stable for duration of the study (2 years)
Purity: 99.0% to 101.0%
Appearance: White crystals
Storage conditions: 4 'C in the dark
Date received: 16 November 1993

Test animals / tissue source

Species:

rabbit

Strain:

New Zealand White

Details on test animals or tissues and environmental conditions:

Three healthy adult rabbits of the New Zealand White strain were obtained from Froxfield (U .K.)
Ltd., Petersfield, Hampshire, England.
The animals were in the weight range of 2.5 to 3.5 kg and approximately 11 to 15 weeks of age,
prior to treatment (Day I). All rabbits were acclimatised to the experimental environment.
The rabbits were selected without conscious bias for the study. They were housed individually in
plastic cages with perforated floors in Building R 14 Room 1.
A standard laboratory diet SDS Stanrab (P) Rabbit Diet and drinking water were provided ad libitum.
The batch of diet used for the study was not analysed for nutrients, contaminants or micro-organisms.
Results of routine chemical examination of drinking water at source as conducted usually weekly by
the supplier, are made available to Huntingdon Research Centre Ltd. as quarterly summaries.
Animal room temperature was maintained at approximately 19'C and relative humidity at 30 -70%.
These environmental parameters were recorded daily. Air exchange was maintained at approximately
19 air changes per hour and lighting was controlled by means of a time switch to give 12 hours of
artificial light (0700 - 1900 hours) in each 24 hours period.
Each animal was identified by a numbered aluminium tag placed through the edge of one ear. This
number was unique within the HRC Indllstrial Toxicology Department throughout the duration of the
study. Each cage, was identified by a coloured label displaying the study schedule number, animal
number and initials of the Study Director and Home Office licensee.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: Second eye of each rabbit

Amount / concentration applied:

One animal was treated in advance of the others, to ensure that if a severe response was produced,
no further animals would be exposed (pilot animal see Table 1).
Approximately 90 mg of the test substance, the weight occupying a volume of 0.1 ml, was placed into
the lower everted I id of one eye of each animal
The eyelids were then gently held together for one second before releasing. The contralateral eye
remained untreated.

Duration of treatment / exposure:

The eyes of each animal were examined prior to instillation of the test substance to ensure that there
was no pre-existing corneal damage, iridial or conjunctival inflammation.

Observation period (in vivo):

Clinical signs
All animals were observed daily for signs of ill health or toxicity.
Ocular responses
Examination of the eyes was made after 1 hour and 1, 2, 3 (equivalent to 24, 48 and 72 hours after
instillation), 4 and 7 days after instillation. Observation of the eyes was aided by the use of a
handheld light.

Number of animals or in vitro replicates:

3

Results and discussion

In vivo

Results

Results 1

Irritation parameter:

cornea opacity score

Basis:

mean

Time point:

other: 1h;24h;48h;72h

Score:

0

Max. score:

0

Results 2

Irritation parameter:

iris score

Basis:

mean

Time point:

other: 1h;24h;48h;72h

Score:

0

Max. score:

0

Results 3

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 1h

Score:

2

Max. score:

2

Reversibility:

fully reversible within: 2 days

Results 4

Irritation parameter:

conjunctivae score

Basis:

mean

Time point:

other: 24h

Score:

1

Reversibility:

fully reversible within: 2 days

Results 5

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 1h

Score:

2

Max. score:

2

Reversibility:

fully reversible within: 2 days

Results 6

Irritation parameter:

chemosis score

Basis:

mean

Time point:

other: 48h

Score:

0

Max. score:

2

Irritant / corrosive response data:

CLINICAL SIGNS
There were no signs of toxicity or ill health in any rabbit during the observation period.
OCULAR RESPONSES
The numerical values given to the ocular reactions elicited by L-Aspartic acid are shown in Table I.
Dulling of the normal lustre of the cornea was seen in all three animals one hour after instillation
only.
No iridial inflammation was observed.
A diffuse crimson red colouration of the conjunctivae accompanied by swelling with partial eversion
of the eyelids was seen in all three animals one hour after instillation. These reactions gradually
ameliorated and had resolved completely two days after instillation.
The eyes were normal two days after instillation

Any other information on results incl. tables

CLINICAL SIGNS There were no signs of toxicity or ill health in any rabbit during the observation period. OCULAR RESPONSES The numerical values given to the ocular reactions elicited by L-Aspartic acid are shown in Table I. Dulling of the normal lustre of the cornea was seen in all three animals one hour after instillation only. No iridial inflammation was observed. A diffuse crimson red colouration of the conjunctivae accompanied by swelling with partial eversion of the eyelids was seen in all three animals one hour after instillation. These reactions gradually ameliorated and had resolved completely two days after instillation. The eyes were normal two days after instillation

Instillation of L-Aspartic acid into the rabbit eye elicited dulling of the normal lustre of the cornea and transient well-defined conjunctival irritation

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information

Executive summary:

A study was performed to assess the eye irritation potential of L-Aspartic acid to the rabbit. The method followed was that described in EEC Methods for the determination of toxicity, Annex to Directive 92/69/EEC (OJ No. L383A, 29.12.92), Part B, Method B.5. Acute toxicity (eye irritation). Three rabbits were each administered a single ocular dose of 90 mg of the test substance and observed for seven days after instillation. A single instillation of L-Aspartic acid into the eye of the rabbit elicited dulling of the cornea and transient well-defined conjunctival reactions. All reactions had resolved two days after instillation. L-Aspartic acid does not require labelling with the risk phrase R36 "Irritating to eyes", in accordance with Council Directive 79/83l/EEC, Annex VI, Part II (D) as described in Commission Directive 93/211EEC.