Melamine

Eye irritation

Administrative data

Endpoint:

eye irritation: in vivo

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

other: Old publication, not according to any guidelines, poor description of the method.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1955

Report date:

1955

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

The test item was applied in the conjunctival sac of the left eyes to 2 groups of 3 albino rabbits each undiluted (30 mg of the dry powdered melamine) and as a 10 % suspension in a 0.5 % solution of methyl cellulose at a dosage of 0.05 cc . The eyes were held closed for approximately one minute. The right eyes served as control.

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Melamine

EC Number:

203-615-4

EC Name:

Melamine

Cas Number:

108-78-1

Molecular formula:

C3H6N6

IUPAC Name:

1,3,5-triazine-2,4,6-triamine

Details on test material:

- Name of test material (as cited in study report): Melamine- Chemical name: 2,4,6-Triamino-1,3,5-triazine- Molecular formula (if other than submission substance): C3H6N6- Molecular weight (if other than submission substance): 126- Analytical purity: 99 % minimum- Stability under test conditions: Stable in aqueous solution and to moderate heating. Deammonation occurs when heated above melting point. (350 ° C).

Test animals / tissue source

Species:

rabbit

Test system

Vehicle:

other: Undiluted and as a 10 % suspension in 0.5 % methyl cellulose solution.

Controls:

no

Duration of treatment / exposure:

1 minute

Observation period (in vivo):

Maximum of 10 days

Number of animals or in vitro replicates:

6

Results and discussion

In vivo

Results

Irritation parameter:

other: Verbal; before the Draize scheme.

Basis:

animal: each

Time point:

other: each

Remarks on result:

other: See remarks.

Remarks:

Administration of the undiluted test item: The observation immediately after application showed the treated eyes of all three rabbits to be moderately irritated, subsiding to mildness at the one and four-hour observation period. Normal appearing of all three animals after 24 hours and continued so throughout the observation period. Administration of the 10 % suspension in a 0.5 % solution of methyl cellulose: No noticeable irritation observed at any time.

Other effects:

No gross pathology was observed when the animals were sacrificed.

Any other information on results incl. tables

Administration of the undiluted test item: The observation immediately after application showed the treated eyes of all three rabbits to be moderately irritated, subsiding to mildness at the one and four-hour observation period. Normal appearing of all three animals after 24 hours and continued so throughout the observation period.

Administration of the 10 % suspension in a 0.5 % solution of methyl cellulose: No noticeable irritation observed at any time.

Applicant's summary and conclusion

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Three study results are available, Hofmann 1969, Shaffer 1955 and Marhold 1972. Two rather old studies, Hofmann 1969 and Shaffer 1955, are used in a weight of evidence approach. Consistent results are reported. These 2 studies do not meet fully the current guidelines (e.g. only 30 or 50 mg test substance were instilled), but they are considered to be adequate for the purpose of classification and for coverage of the key parameters foreseen to be investigated in the corresponding test methods. The third study is considered to be unreliable.

Executive summary:

When a 30 mg dose of the dry powdered melamine was placed in the conjunctival sac of the left eyes of albino rabbits there was some irritation in all animals immediately, disappearing within 24 hours, and the eyes then remained normal for the duration of the observation.

When a 10 % suspension of melamine in a 0.5 % methyl cellulose solution was applied in 0.05 cc doses to the eyes of albino rabbits, no irritation was noted at any time during the observation period.