Diethyl phenylphosphonite

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: scientifically acceptable study report, only 6 animals tested instead of 10 as requested in the guideline

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1997

Report date:

1997

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Version / remarks:

1981-05-12

Deviations:

yes

Remarks:

6 animals tested instead of 10

Principles of method if other than guideline:

The study procedure was based on the OECD Guidelines, Method 403, 1981 and the "range-finding toxicity test" published by H.F. Smyth et al., 1962.

GLP compliance:

yes

Remarks:

but no QAU audit of the report performed

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1683-86-4

IUPAC Name:

1683-86-4

Test material form:

other: liquid vapour

Details on test material:

- Name of test material (as cited in study report): Diethoxyphenlyphosphin- DEOPP
- Physical state: liquid, colourless
- Analytical purity: 98.4 g/100g (GC)
- Lot/batch No.: 96-1008-9-HL
- Date of manufacturing: 1996-07-11
- Storage condition of test material: room temperature, exclusion of moisture, light and oxygen (store under nitrogen)

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Dr. K. Thomae GmbH, Biberach, FRG)
- Age at study initiation: 8-9 weeks
- Weight at study initiation: females: 190,6g +/- 7,4 g, males: 267,6g +/- 12,9 g
- Housing: single housing, DK III Becker cages, without bedding
- Diet: KLIBA laboratory diet 10 mm pellets, Klingentalmühle AG, Kaiseraugst, Switzerland, ad libitum
- Water: ad libitum
- Acclimation period: 1 week

ENVIRONMENTAL CONDITIONS
- Temperature (°C):20-24
- Humidity (%):30-70
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

nose/head only

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: glass generator containing product placed in a waterbath (20 °C), a stream of 200 L/h compressed air was bubbled through the the substance column, the inhalation atmosphere was passed through a downstream mixing chamber and a glass distributor to 6 glass tubes containing the animals
- Method of conditioning air: replacing generator after 30 minutes
- Temperature, humidity, pressure in air chamber: 19-25 °C

TEST ATMOSPHERE
- Brief description of analytical method used: The amount of test substance consumed was determined by reweighing the generators. The nominal concentration was calculated from the amount of test substance consumed and the total air volume used.

Analytical verification of test atmosphere concentrations:

no

Remarks on duration:

4 and 7 hours

Concentrations:

0.5 mg/L nominal (saturated vapour concentration = 0.32mg/L)

No. of animals per sex per dose:

3

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: body weights of surviving animals were determined prior to exposure, after 7 days and at the end of the observation period. A check for overt clinical signs of toxicity or mortality as well as a check for feed and drinking water was made twice a day.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other: gross-pathological examination of all animals

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 0.32 mg/L air

Based on:

test mat.

Exp. duration:

4 h

Remarks on result:

other: saturated vapour concentration

Effect levels 2

Sex:

male/female

Dose descriptor:

LC50

Effect level:

> 0.32 mg/L air

Based on:

test mat.

Exp. duration:

7 h

Remarks on result:

other: saturated vapour concentration

Mortality:

7-hour exposure and 4-hour exposure: 2/6 animals in each experiment

Clinical signs:

other: The animals which were exposed for 4 h showed attempts to escape, irregular and accelerated respiration, respiratory sounds, squatting posture and piloerection. In the animals exposed for 7 h apathy was observed additionally. No clinical symptoms were obs

Body weight:

Body weight development was decreased in the first post exposure week, but recovered in the second in both exposure groups.

Gross pathology:

During necropsy, agonal congestive hyperemia and focal dark red discoloration of the lungs was observed in the animals that died.
The animals examined at termination of the study showed no abnormalities.

Applicant's summary and conclusion

Interpretation of results:

toxic

Remarks:

Migrated information