Dipotassium oxide

Acute Toxicity: dermal

Administrative data

Endpoint:

acute toxicity: dermal

Type of information:

other: Published data

Adequacy of study:

key study

Study period:

October 19 - November 2, 2000

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Justification for type of information:

According to OECD 402 and GLP procedures. Alternatively and more conveniently Potassium oxide is synthesized by heating potassium nitrate with metallic potassium: 2 KNO3 + 10 K → 6 K2O + N2 Therefore, the health effects of potassium nitrate need to be considered in the assessment of Potassium oxide

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2000

Report date:

2000

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 402 (Acute Dermal Toxicity)

Deviations:

no

Principles of method if other than guideline:

limit dose of 5,000 mg/kg tested

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Potassium nitrate

EC Number:

231-818-8

EC Name:

Potassium nitrate

Cas Number:

7757-79-1

Molecular formula:

HNO3.K

IUPAC Name:

Potassium nitrate

Details on test material:

Alternatively and more conveniently Potassium oxide is synthesized by heating potassium nitrate with metallic potassium:2 KNO3 + 10 K → 6 K2O + N2Therefore, the health effects of potassium nitrate need to be considered in the assessment of Potassium oxidewhite granules- Analytical purity: K2O - 44.86%Total Nitrogen - 13.54%- Lot/batch No.: - Expiration date of the lot/batch: July 6, 2001- Stability under test conditions: Test substance is expected to be stable for the duration of testing- Storage condition of test material: room temperature

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Received from Ace Animals, Inc., Boyertown, PA on October 10, 2000
- Age at study initiation: Young adult (8-9 weeks)
- Weight at study initiation: males 218-246 grams and females 194-215 grams at experimental start
- Fasting period before study:
- Housing: The animals were singly housed in suspended stainless steel caging with mesh
floors which conform to the size recommendations in the most recent Guide for the
Care and Use of Laboratory Animals DHEW (NIH). Litter paper was placed beneath
the cage and was changed at least three times per week.
- Diet (e.g. ad libitum): Purina Rodent Chow #5012
- Water (e.g. ad libitum): Filtered tap water was supplied ad libitum by an automatic water dispensing
system.
- Acclimation period: 9 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 17-21C
- Humidity (%):
- Air changes (per hr):
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle

Administration / exposure

Type of coverage:

occlusive

Vehicle:

other: moistened with water

Details on dermal exposure:

TEST SITE
- Area of exposure: dose area of approximately 2 inches x 3 inches
- % coverage: approximately 10% of the body surface

REMOVAL OF TEST SUBSTANCE
- Washing (if done): yes, with water
- Time after start of exposure: 24 h

TEST MATERIAL
- Amount(s) applied (volume or weight with unit): (conc. 85%)Five thousand mg/kg of bodyweight of the
test substance (6.25 g/kg of test mixture)
- Constant volume or concentration used: yes
- For solids, paste formed: yes

Duration of exposure:

24 hours

Doses:

(conc. 85%) Five thousand mg/kg of bodyweight of the test substance (6.25 g/kg of test mixture)

No. of animals per sex per dose:

5 males and 5 females

Control animals:

not specified

Details on study design:

- Duration of observation period following administration: 14 days (or other?) 14 days
- Frequency of observations and weighing:
- Necropsy of survivors performed: yes/no Yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other:
The animals were observed for mortality, signs of gross toxicity, and behavioral changes at 1 and 5
hours after application and at least once daily thereafter for 14 days. Observations included gross
evaluation of skin and fur, eyes and mucous membranes, respiratory, circulatory, autonomic and central
nervous systems, somatomotor activity and behavior pattern. Particular attention was directed to
observation of tremors, convulsions, salivation, diarrhea and coma.

Gross necropsies were performed on all animals. Tissues and organs of the thoracic and abdominal cavities were examined.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

all animals survived

Clinical signs:

other: all animals appeared active and healthy

Gross pathology:

Gross pathology: All animals survived, gained weight and appeared active and healthy. There were no signs of gross toxicity, adverse pharmacologic effects or abnormal behavior. No gross abnormalities were noted for the animals necropsied at the conclusion of the 14-day observation period.

Applicant's summary and conclusion

Interpretation of results:

other: not classified

Remarks:

Criteria used for interpretation of results: EU

Conclusions:

Acute Dermal Toxicity: An LD50 value of >5000 mg/kg was obtained. The dermal LD50 in male and female rats is >5000 mg/kg.
Alternatively and more conveniently Potassium oxide is synthesized by heating potassium nitrate with metallic potassium:
2 KNO3 + 10 K → 6 K2O + N2
Therefore, the health effects of potassium nitrate need to be considered in the assessment of Potassium oxide