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Toxicological information

Acute Toxicity: inhalation

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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: well documented non GLP study report that is similar to OECD Guideline 403

Data source

Referenceopen allclose all

Reference Type:
study report
Title:
Unnamed
Year:
1981
Report Date:
1981
Reference Type:
publication
Title:
INHALATION TOXICITY OF ACETALDEHYDE IN RATS. I. ACUTE AND SUBACUTE STUDIES
Author:
LMI. APPELMAN, R.A. WOUTERSEN and V.J. FERON
Year:
1982
Bibliographic source:
Toxicology, 23 (1982) 293-307

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
Guideline:
OECD Guideline 403 (Acute Inhalation Toxicity)
GLP compliance:
not specified
Test type:
standard acute method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Acetaldehyde (grade: for sythesis) was obtained from Merck-Schuchardt, Germany

Test animals

Species:
rat
Strain:
Wistar
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Central institute for breeding of Laboratory animals TNO, Zeist, Netherlands.
- Age at study initiation: no data
- Weight at study initiation (mean): 191 g and 149 g for males and females respectively
- Fasting period before study: no data
- Housing: per sex, five to a cage
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: no data


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22+/-1 °C
- Humidity (%): 40-60%
- Air changes (per hr): no data
- Photoperiod (hrs dark / hrs light): 12/12

Administration / exposure

Route of administration:
inhalation: vapour
Type of inhalation exposure:
whole body
Vehicle:
other: unchanged (no vehicle)
Details on inhalation exposure:
GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: The animals were exposed in horizontally placed glass exposure cylinders, fitted with an interior of perforated stainless steel plate to separately accommodate ten rats.
- Exposure chamber volume: cylinder with 0.9x0.15 m
- Method of holding animals in test chamber: see above
- Source and rate of air: 8 l/min
- Method of conditioning air: filtered and dried nitrogen was passed through a glass evaporator filled with acdtaldehyde kept at a temperature of 4 °C. To obtain the desired acetaldehyde concentration in the test atmosphere the nitrogen flow loaded with acetaldehyde was miced in the proper ratio with the main airflow passed through the exposure chambers.
- Temperature, humidity, pressure in air chamber: 23 °C

TEST ATMOSPHERE
- Brief description of analytical method used: gaschromatography (Intersmat GC 120) with a flame ionistation detector

DOSE SELECTION
available data from Syrian hamster (Kruysse, 1970): LC50 31 g/m3; 4 h

Analytical verification of test atmosphere concentrations:
yes
Duration of exposure:
4 h
Concentrations:
10436 ppm, 12673 ppm, 15683 ppm, 16801 ppm
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: subsequent obervation; weighing at day 0, 1, 2, 4, 7, 14
- Necropsy of survivors performed: no
- Other examinations performed: clinical signs, body weight,organ weights, histopathology, other:
Statistics:
The 4 hour LC50 and the 95% confidence limit were calculated according to Finney (1971)

Results and discussion

Effect levelsopen allclose all
Sex:
male/female
Dose descriptor:
LC50
Effect level:
13 300 ppm
95% CL:
11 200 - 15 400
Exp. duration:
4 h
Sex:
male/female
Dose descriptor:
LC50
Effect level:
24 040 mg/m³ air
95% CL:
20 250 - 27 840
Exp. duration:
4 h
Mortality:
All animals that died, died within a period of 2 days after termination of the exposure, except for one animal exposed to the 15683 ppm acetaldehyde that died on day 6 of the observation period.
Clinical signs:
other: During the first half an hour of the exposure period the animals were restless, kept their eyes closed and showed a laboured respiration. After approximately one hour the animals were lying with their eyes open and showed severe mouth breathing.
Body weight:
Both males and females lost body weight during the first day of the observation period. Thereafter they gained weight in a normal way, exept for the females of the 15683 ppm group, which gained weight in a normal way nut until the second week.
Gross pathology:
no data
Other findings:
-

Any other information on results incl. tables

Table 1.Overview on the deaths (male and female) during the exposure period and the complete experiment, respectively.

 

concentration[ppm]

Number of deaths during exposure

Number of deaths during the complete experiment

Total mortality [%]

10436

1

1

20

12673

-

5

50

15683

2

7

60

16801

6

8

80

 

Applicant's summary and conclusion

Conclusions:
Acetaldehyde has a low toxicity after inhaltion under the reported conditions. The LC 50 (4h) is 24.04 mg/L.
Executive summary:

Acetaldehyde was investigated for inhalation toxicity in an experimental study that was similar to OECD Guideline 403. From the observed mortalities after 4 hours exposure the LC 50 was calculatad as 24.04 mg/L (13300 ppm). Acetaldehyde could thus be considered as of low toxicity when inhaled.