2-amino-6-methyl-4-propyl-1,2,4-triazolo[1,5-a]pyrimidin-5(4H)-one

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1988

Report date:

1988

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Five rats per sex were exposed to a single dermal dose of 2000 mg/kg bw test substance under occlusive conditions. The test substance was removed with clean warm water after the exposure period followed by a 14-day observation period.

GLP compliance:

no

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-amino-6-methyl-4-propyl-1,2,4-triazolo[1,5-a]pyrimidin-5(4H)-one

EC Number:

248-383-5

EC Name:

2-amino-6-methyl-4-propyl-1,2,4-triazolo[1,5-a]pyrimidin-5(4H)-one

Cas Number:

27277-00-5

Molecular formula:

C9H13N5O

IUPAC Name:

2-amino-6-methyl-4-propyl-1,2,4-triazolo[1,5-a]pyrimidin-5(4H)-one

Test material form:

solid: particulate/powder

Details on test material:

- Carbon content: 52.2%
- ThOD: 2.310 mg O2/mg considering total nitrification; 1.027 mg O2/mg considering no nitrification
- Water solubility (SDS): 2 g/L very slightly soluble
- Vapour pressure (SDS): 0.00003 mm Hg at 25°C
- State of matter and appearance (CoA): Off-white to beige powder
- Storage conditions (CoA): At < 30°C in a tightly closed container at a dry and well-ventilated place.
- Waste disposal: Waste will be disposed of in accordance with federal, state and local environmental control regulations.

Test animals

Species:

rat

Strain:

other: albino

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 222 - 250 g for males and 168 - 192 g for females

Administration / exposure

Type of coverage:

occlusive

Vehicle:

water

Details on dermal exposure:

REMOVAL OF TEST SUBSTANCE
- Washing: yes, with clean warm water

TEST MATERIAL
- For solids, paste formed: yes

Duration of exposure:

24 hours

Doses:

2000 mg/kg bw

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Examinations performed: clinical signs (daily), skin irritation (daily), body weight, gross pathology.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

discriminating dose

Effect level:

2 000 mg/kg bw

Based on:

test mat.

Mortality:

No mortality observed

Clinical signs:

other: The signs of toxicity (stains around nose, urinary incontinence, diarrhoea and signs of diarrhoea) observed in some animals up to day three were probably due to the occlusive dressings.

Gross pathology:

No macroscopic abnormalities were detected at necropsy.

Other findings:

Slight erythema was observed in one male rat on day 2. No signs of skin irritation were observed during the study.

Applicant's summary and conclusion

Conclusions:

It can be concluded that the dermal acute LD50 in rats is > 2000 mg/kg bw.

Executive summary:

Five rats per sex were exposed to a single dermal dose of 2000 mg/kg bw test substance under occlusive conditions for 24 hours. The test substance was removed with clean warm water after the exposure period followed by a 14-day observation period. No mortality was observed. The signs of toxicity (stains around nose, urinary incontinence, diarrhoea and signs of diarrhoea) observed in some animals up to day three were probably due to the occlusive dressings. All animals regained their initial body weights by the end of the study and no macroscopic abnormalities were detected at necropsy. Slight erythema was observed in one male rat on day 2. No signs of skin irritation were observed during the study. Under the conditions of the test it can be concluded that the dermal acute LD50 value in rats is > 2000 mg/kg bw.