Cyanoacetic acid

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study, no GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1981

Report date:

1981

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Principles of method if other than guideline:

BASF Test (BASF internal method). In principle, the methods described by OECD TG 403 are followed.

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Cyanoacetic acid

EC Number:

206-743-9

EC Name:

Cyanoacetic acid

Cas Number:

372-09-8

Molecular formula:

C3H3NO2

IUPAC Name:

cyanoacetic acid

Details on test material:

- Name of test material (as cited in study report): Cyanessigsäure (cyanoacetic acid)
- Physical state: solid (white, crystalline)
- Analytical purity: 97%
- Impurities (identity and concentrations): no data
No further data

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
male and female Sprague-Dawley rats, outbred strain: Caw-Ico-Wiga
- Source: WIGA Versuchstierzuchtanstalt, Sulzfeld (Germany)
- Age at study initiation: 7 -11 weeks
- Weight at study initiation: 185 +/- 15 g
- Housing: 5 per cage, in type D III / MD III cages
- Diet (ad libitum): Herilan MRH, H. Eggersmann KG, Rinteln/Weser (Germany)
- Water (ad libitum): tap water

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24 °C
- Humidity (%): 50 - 60 %
- Photoperiod (hrs dark / hrs light): 12/12

IN-LIFE DATES: no data

Administration / exposure

Route of administration:

inhalation: aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

other: water

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
Head/nose inhalation system: The animals are placed in tubes, with their heads being projected into the inhalation chamber.

An aerosol was generated from a 50% aqueous solution of the test substance and conducted into the inhalation chamber. Exposure to external air was avoided by increased air pressure within the inhalation system (10% air pressure difference).

TEST ATMOSPHERE
- Brief description of analytical method used: gas chromatography
- Samples taken from breathing zone: yes

VEHICLE
bidistilled water
- Concentration of test material in vehicle (if applicable): 50 wt%
- Justification of choice of vehicle: technical reasons, not further specified

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

analytical concentration: 0.25, 0.65, 1.53, 2.56, 3.94 mg/l;
for details, see freetext below (Table 1)

No. of animals per sex per dose:

10 males and 10 females per dose group

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Animals were weighed at study initiation, at 7 days after exposure, and at the end of the observation period.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, gross pathology

Statistics:

Probit analysis according to Finney DJ (1971). Probit analysis. Published by the Syndics of the Cambridge University Press, Bentley House, 200 Euston Road, London NW 1: 1-150.

Results and discussion

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LC50

Effect level:

1.9 mg/L air (analytical)

Exp. duration:

4 h

Remarks on result:

other: 95% confidence; slope factor = 2.26

Effect levels 2

Sex:

male

Dose descriptor:

LC50

Effect level:

1.4 mg/L air (analytical)

Exp. duration:

4 h

Effect levels 3

Sex:

female

Dose descriptor:

LC50

Effect level:

2.6 mg/L air (analytical)

Exp. duration:

4 h

Mortality:

Mortality rates:
- group 1 (3.94 mg/l analytical): 10/10 males, 9/10 females
- group 2 (2.56 mg/l analytical): 5/10 males, 4/10 females
- group 3 (1.53 mg/l analytical): 7/10 males, 1/10 females
- group 4 (0.65 mg/l analytical): 2/10 males, 1/10 females
- group 5 (0.25 mg/l analytical): 0/10 males, 0/10 females

Deaths occurred as early as during exposure but also as late as at day 11 post exposure.

Clinical signs:

other: During exposure, the following signs of toxicity were observed: group 1: serous secretion at the eyes and nose, salivation, eyelid closure, swollen snouts with reddish encrustations, dyspnea, retarded pain reflex, tremor, squatting posture, high-legged

Body weight:

The following effects on body weight / body weight gain were noted:
- group 1: marked body weight loss during the observation period (both sexes).
- groups 2 and 3: retarded body weight gain during the first 7 days after exposure, partial recovery during the second week (both sexes).
- group 4: retarded body weight gain during the observation period in males, no effect on body weight gain in females.
- group 5: no effect on body weight gain (both sexes).
For details, see attached files (tables 2 and 3).

Gross pathology:

Gross pathology of the decedents revealed findings in the heart (acute congestive hyperemia), lungs (increased plethora, multiple pulmonary edema, slight acute pulmonary emphysema), and liver (hints on markings of the peripheral lobes). No pathological findings were observed in survivors that had been sacrificed at the end of the observation period.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Remarks:

Migrated information