Melamine

Endpoint summary

Description of key information

Melamine do not irritate skin and eyes to a relevant degree. No classification is needed.

Key value for chemical safety assessment

Skin irritation / corrosion

Link to relevant study records

Reference

Endpoint:

skin irritation: in vivo

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study with GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 404 (Acute Dermal Irritation / Corrosion)

Version / remarks:

1992

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

EU Method B.4 (Acute Toxicity: Dermal Irritation / Corrosion)

Version / remarks:

1992

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

EPA OPP 81-5 (Acute Dermal Irritation)

Version / remarks:

1984

Deviations:

not specified

Qualifier:

according to guideline

Guideline:

other: Japanese, 1985

Deviations:

not specified

GLP compliance:

yes

Species:

rabbit

Strain:

New Zealand White

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Broekman Institute, Someren
- Age at study initiation: ca. 7-9 weeks
- Weight at start of treatment: 1224 - 1924 g
- Housing: Individually in label led cages with perforated floors (Scanbur Denmark) and equipped with an automatic drinking system (ITL, Bergen, The Netherlands).
- Diet (e.g. ad libitum): Standard laboratory rabbit diet (LKK-20, pellet diameter 4mm, Hope Farms, Woerden, The Netherlands) approx. 100 g per day. Certificates of analysis were examined and retained in the NOTOX archives.
- Hay (BMI, Helmond, The Netherlands) was provided once a week.
- Water (e.g. ad libitum): Free access to tap-water diluted with decalcified water.
Certificates of analysis were examined and retained in the NOTOX archives.
- Acclimation period: Acclimatisation period was at least 5 days before start of treatment under laboratory conditions

ENVIRONMENTAL CONDITIONS
Air-conditioned room with approximately 15 air changes per hour and the environment controlled with optimal conditions considered as being a temperature of 21°C and a relative humidity of 50 %. Fluctuations from these optimal conditions were noted, but were considered not to have affected study integrity. Lighting was 12 hours artificial fluorescent light and 12 hours dark per day.

Type of coverage:

semiocclusive

Preparation of test site:

shaved

Vehicle:

water

Controls:

not required

Amount / concentration applied:

TEST MATERIAL
- Amount applied: 0.5 g

VEHICLE
- The powdery test substance was moistened with distilled water, immediately before application, to ensure close contact to the animal's skin.

Duration of treatment / exposure:

4 h

Observation period:

ca. 1, 24, 48 and 72 h after removal of the dressings and test substance.

Number of animals:

6

Details on study design:

TEST SITE
- Area of exposure: 2 x 3 cm
- Type of wrap if used: Scotchpak-non-woven patch Micropore tape holding the test substance, which was wrapped around the abdomen and secured with Coban elastic bandage.

REMOVAL OF TEST SUBSTANCE
- With moistened tissue
- Time after start of exposure: 4 h

Irritation parameter:

overall irritation score

Basis:

mean

Time point:

other: 24 - 72 h

Score:

0

Max. score:

0

Reversibility:

other: no irritation

Irritation parameter:

primary dermal irritation index (PDII)

Basis:

mean

Time point:

other: 24 - 72 h

Score:

0

Irritation parameter:

erythema score

Basis:

animal: 1 to 6

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritation parameter:

edema score

Basis:

animal: 1 to 6

Time point:

24/48/72 h

Score:

0

Max. score:

0

Irritant / corrosive response data:

IRRITATION
No skin irritation was caused by MELAMINE after 4 hours of exposure in any of the six animals.
CORROSION
There was no evidence of a corrosive effect on the skin.

Other effects:

COLOURATION
No staining of the treated skin by the test substance was observed.
TOXICITY SYMPTOMS / MORTALITY
No symptoms of systemic toxicity were observed in the animals during the test period and no mortality occurred.

Interpretation of results:

not irritating

Remarks:

Migrated information Criteria used for interpretation of results: other: EU and EPA pesticide

Conclusions:

Dermal application of melamine resulted in no irritation when applied to the intact rabbit skin.

Executive summary:

A skin irritation study with rabbits according to EU-, OECD- and EPA-methods was performed.

Exposure to melamine resulted in no skin irritation in the treated skin-areas of the 6 rabbits. No signs of systemic intoxication were observed during the study period. Dermal application of melamine resulted in a primary irritation index of 0 (non irritating), when applied to the intact rabbit skin.

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Eye irritation

Endpoint conclusion

Endpoint conclusion:

no adverse effect observed (not irritating)

Respiratory irritation

Endpoint conclusion

Endpoint conclusion:

no study available

Additional information

Skin irritation: Four studies are available, with that of Rijcken 1995 meeting current guidelines and GLP. The other 3 are rather old studies and/or poorly described. No irritation of the skin was observed in the 4 studies.

Eye irritation: 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. They report transient slight to moderate changes only soon after instillation, but not at later times. 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. A repetition of the animal experiment seems not to be justified. The third study (Marhold 1972) reports a mild irritation at the only observation time of 24 h p.a., but do not report the follow up at later times (and also uses a too high dose of 500 mg)and is considered to be unreliable.

Respiratory irritation: No study on this endpoint is available.

Justification for classification or non-classification

Skin irritation: No irritation was detected in 4 studies.

Eye irritation: Slight to moderate irritations were detected only at or earlier than 24 h p.a., but not at later times.