DL-malic acid

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

migrated information: read-across based on grouping of substances (category approach)

Adequacy of study:

key study

Study period:

25 April 1984 to 16 May 1984

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Guideline-compliant, proprietary study. Read across to fumaric acid.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 405 (Acute Eye Irritation / Corrosion)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Fumaric acid/ Fumaril

IUPAC Name:

Fumaric acid/ Fumaril

Details on test material:

- Physical state: Solid
- Analytical purity: 99.5%
- odour: odourless

- Name of test material (as cited in study report): fumaric acid

- Impurities (identity and concentrations): benzoic, maleic and phthalic acid <0.05%
- Composition of test material, percentage of components:

- Stability under test conditions:
- Storage condition of test material:
- Other: pH 2.1 at 4.9 g/L density 1.63 g/cm3

Test animals / tissue source

Species:

rabbit

Strain:

other: small white Russian

Details on test animals or tissues and environmental conditions:

Male and female rabbits between 1.9 and 2.1 kg were housed in individual stainless steel cages and acclimated for 14 days. Rabbits received K4 single diet for rabbits (Ssniff Special Feed GmbH) and water ad libitum. Room temperature was 20C with 60% relative humidity. Air was exchanged 15 times per hour and a 12 hr light-dark cycle was employed.

Test system

Vehicle:

unchanged (no vehicle)

Controls:

other: left eyelid of each animal

Amount / concentration applied:

0.1 g fumaric acid

Duration of treatment / exposure:

The test material was not washed out.

Observation period (in vivo):

1, 24, 48 and 72 hours and 5, 7, 9, 12, 15, 19 and 21 days.

Number of animals or in vitro replicates:

3 males and 3 females

Details on study design:

Test material was applied to the lower conjunctival sac of the right eye by pulling away the lower eyelid. The left eye was treated in one animal.
The contralateral eye served as a concurrent, inherent control

Results and discussion

In vivo

Results

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 72 hrs

Score:

42.8

Reversibility:

not fully reversible within: 21 days

Irritant / corrosive response data:

The mean values over the 24, 48 and 72 hour post-instillation observations were:

corneal opacity = 2.0
Iris = 0.28
Conjunctival redness = 2.83
conjunctival chemosis = 1.72

Any other information on results incl. tables

Table 1. Cornea Evaluation: Degree of Opacity (A) x Extent of Opacity (B) x 5

Animal number	1 hr				24 hr			48 hr				72 hr
	A		B	AxBx5		A	B	AxBx5		A	B	AxBx5	A	B	AxBx5
1	1		4*	20		1	4	20		1	4	20	1	4	20
2	1		4	20		1	4	20		1	4	20	2	4	40
3	2		4	20		2	4+	40		2	4+	40	3	2-	30
4	2		4	20		3	2	30		4	2-	40	4	2-	40
5	2		4	20		1	4+	20		4	2-	40	3	2-	30
6	1		4	20		1	4	20		1	4	20	1	4	20
Mean				30				25				30			30
*Circular streak (0-4 mm) on the pupil; +Spot on the cornea with opacity up to white coloration; - Remaining surface: reduction in normal clarity

Table 2. Iris Evaluation: A = Change

Animal number	1 hr		24 hrs		48 + 72 hrs
	A	A x 5	A	A x 5	A	A x 5
1	0	0	0	0	0	0
2	0	0	0	0	0	0
3	0	0	0	0	1*	5
4	0	0	0	0	0	0
5	0	0	1*	5	1*	5
6	0	0	0	0	0	0
Mean		0		0.83		1.67
*Circumcorneal injection

Table 3. Conjunctive Evaluation: Redness (A) + Swelling (B) + Exudation (C)

Animal number	1 hr				24 hrs				48 hrs				72 hrs
	A	B	C	(A+B+C) 2	A	B	C	(A+B+C) 2	A	B	C	(A+B+C) 2	A	B	C	(A+B+C) 2
1	2	2	2	12	3	2	2	14	3	1	2	12	3	1	1	10
2	2	3	2	14	3	2	2	14	2	2	2	12	3-	2	1	12
3	2*	3	2	14	2	2	2	12	3-	2	2	14	3-	2	1	12
4	2	3	2	14	3+	2	3	16	3	2	3	16	3-	2	2	14
5	2*	2	2	12	2	2	2	12	3	1	2	12	3-	1	2	12
6	2	2	2	12	3	2	2	14	3	2	2	14	3	1	2	12
Mean				13				13.67				13.33				12.0
*Necrotic spots on mucous membrane; +Skin-like mucous on the cornea; -White layer is exuded from the mucous membrane

Applicant's summary and conclusion

Interpretation of results:

moderately irritating

Remarks:

Migrated information Criteria used for interpretation of results: OECD GHS

Conclusions:

This study supports the conclusion that fumaric acid and malic are moderate eye irritants requiring classification.

Executive summary:

Read across to fumaric acid is considered valid and malic acid is concluded to be irritating to eyes and classification is required

It is not considered valid to perform further animal tests on malic acid.

Application of 0.1 g fumaric acid to the eyes of male and female rabbits was considered moderately irritating to the eye and ocular mucous membrane. Fumaric acid is classified as an eye irritant. It is assigned the symbol Xi and the risk-phrase R36 - irritating to the eyes according to Directive 67/548/EEC. It is assigned the pictogram GHS07 with the signal word warning and the hazard statement H319 "causes serious eye irritation".