Hydroxyl-2-pyridone

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

experimental study

Adequacy of study:

key study

Study period:

March 30-April 22, 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1995

Report date:

1995

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.3 (Acute Toxicity (Dermal))

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

other: US EPA FIFRA Pesticide Assessment Guidelines

Version / remarks:

1984

Deviations:

no

GLP compliance:

yes

Test type:

fixed dose procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Hydroxyl-2-pyridone

EC Number:

212-506-0

EC Name:

Hydroxyl-2-pyridone

Cas Number:

822-89-9

Molecular formula:

C5H5NO2

IUPAC Name:

1-hydroxy-1,2-dihydropyridin-2-one

Test material form:

solid: particulate/powder

Details on test material:

- Name of test material (as cited in study reports): Oxy PYRION
- Physical state: solid (powder)
- Appearance: white speckled gold powder

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 93100020

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: Stable

Test animals

Species:

rat

Strain:

other: CD strain, remote Sprague-Dawley origin

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River (UK) Limited, Margate, Kent, England
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: Males-7-8 weeks, Females-10-11 weeks
- Weight at study initiation: Males-240-254 g; Females-228-250 g
- Fasting period before study: no
- Housing: Stainless steel cages with grid floors, with absorbant paper beneath; 5 animals per sex per cage
- Diet (e.g. ad libitum): Commercially available rodent diet, ad libitum
- Water (e.g. ad libitum): Public tap water supply, ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 21 degrees C (18-25 range)
- Humidity (%): 55 % (40-70% range)
- Air changes (per hr): 10
- Photoperiod (hrs dark / hrs light): 12 hours dark/12 hours light

Administration / exposure

Type of coverage:

occlusive

Vehicle:

unchanged (no vehicle)

Details on dermal exposure:

TEST SITE
- Area of exposure: Dorsal surface
- % coverage: 5 cm x 5 cm area (at least 10% of the body surface area)
- Type of wrap if used: The test material was applied to a 5 cm x 5 cm gauze patch, placed on the dorsum and occluded with aluminium foil. The foil was kept in place by a cotton wool pad and protected by a bandage of waterproof plaster wrapped twice around the trunk of the body with sufficient tension to ensure the dose remained securely in place.

REMOVAL OF TEST SUBSTANCE
- Washing (if done): Wiped with wet disposable tissues to remove residual test material.
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): 2000 mg/kg bodyweight
- Constant volume or concentration used: yes
- For solids, paste formed: no

Duration of exposure:

24 h

Doses:

1

No. of animals per sex per dose:

5 males, 5 females

Control animals:

not required

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observations-3 in hour 1, plus 2 more on day 1, twice daily thereafter. Weighing-Day 1, 8, and 15.
- Necropsy of survivors performed: yes: all animals were killed by carbon dioxide inhalation at terination of the study. Each animal was thoroughly examined for abnormity of tissues or organs. All body cavities were opened, larger organs were sectioned and the gastro-intestinal tract was opened at intervals for examination of the mucosal surfaces. All abnormalities were described or the normal appearance of major organs was confirmed. No tissues were retained in fixative.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Remarks on result:

no indication of skin irritation up to the relevant limit dose level

Mortality:

No mortality was observed.

Clinical signs:

Pigmented staining of snout and pigmented orbital secretion was observed on day 2. All animals were overtly normal on day 3.

Body weight:

All animals achieved expected bodyweights.

Gross pathology:

No significant macroscopic lesions were observed at necropsy on day 15.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

For the test item, the LD50 was > 2000 mg/kg bodyweight; therefore it is considered to be of low percutaneous toxicity.