tert-butyl acrylate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1979

Report date:

1979

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

tert-butyl acrylate

EC Number:

216-768-7

EC Name:

tert-butyl acrylate

Cas Number:

1663-39-4

Molecular formula:

C7H12O2

IUPAC Name:

tert-butyl acrylate

Specific details on test material used for the study:

- Name of test material: Tertiaerbutylacrylat
- Physical state: clear liquid
- Analytical purity: ca. 99.5 %
- Impurities: stabilized with 15 ppm Hydrochinonmonomethylether

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Wiga, Sulzfeld, D (SPF breeding)
- Weight at study initiation: 185 ± 15g
- Fasting: no
- Diet (ad libitum): Herilan MRH (H. Eggersmann KG, Rinteln, D)
- Water (ad libitum): tap water

ENVIRONMENTAL CONDITIONS
- standardized conditions (unspecified)

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: permanent infusion pump (UNITA)
- Exposure chamber volume: 200 L
- Source and rate of air: 3000 - 3100 L/h
- System of generating particulates/aerosols: heatable vaporisator, electric (BASF)
- Treatment of exhaust air: vacuum system with underpressure (9.8 Pa)

TEST ATMOSPHERE
- Brief description of analytical method used: GC HP 5840 A, detector: FID; the atmosphere was absorbed with propanol-2 in two wash bottles in serial configuration; ca. 1 L/min
- Samples taken from breathing zone: yes

CLASS METHOD
- Rationale for the selection of the starting concentration: based on results of an inhalation hazard test

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

8.78; 7.42; 6.30; 5.35; 5.24; 2.96 mg/L (analytical concentrations, vapour)

No. of animals per sex per dose:

20

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: daily observations, weighing was performed on d0, d7 and d14
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs

Statistics:

Probit analysis (Finney, 1971)

Results and discussion

Effect levels

Effect levels 1

Key result

Sex:

male/female

Dose descriptor:

LC50

Effect level:

7.01 mg/L air (analytical)

95% CL:

6.65 - 7.45

Exp. duration:

4 h

Effect levels 2

Sex:

female

Dose descriptor:

LC50

Effect level:

7.3 mg/L air (analytical)

Exp. duration:

4 h

Remarks on result:

other: no confidence interval calculated due to inadequate homogeneity

Effect levels 3

Sex:

male

Dose descriptor:

LC50

Effect level:

6.75 mg/L air (analytical)

95% CL:

6.3 - 7.32

Exp. duration:

4 h

Mortality:

- 8.78 mg/L: 20/20
- 7.42 mg/L: 11/20
- 6.30 mg/L: 3/20
- 5.35 mg/L: 1/20
- 5.24 mg/L: 2/20
- 2.96 mg/L: 0/20
- control: 0/20
See table for details

Clinical signs:

other: Attempts to escape, lid closure, reddish eye and nose discharge, crusted nose and eyes, accelerated or intermittend respiration, high-stepping or unstable gait, squatting posture, reduced motility, tremor, reddish ears and extremities, ruffled fur. Signs

Body weight:

Males of the 7.42 mg/L treatment had a ca. 40% lower weight gain after 14 d if compared with the control. The mean body weight gain of the females in all treatment groups was somewhat lower than the control in the first observation week, while their weight gain was comparable with the control in the second week.
See table for details

Gross pathology:

Animals that died: generally: acute heart dilatation, acute congestion hyperemia; highest dose group: liver with rare and slight broadening of the lobules; lower doses: in some animals slight acute lung dilution
Sacrificed animals: nothing abnormal found

Any other information on results incl. tables

Cumulated mortality
Dose (mg/L)	sex	after 7 d	after 14 d
8.78	male	10/10	10/10
	female	10/10	10/10
7.42	male	7/10	7/10
	female	4/10	4/10
6.30	male	3/10	3/10
	female	0/10	0/10
5.35	male	0/10	0/10
	female	0/10	0/10
5.24	male	0/10	0/10
	female	2/10	2/10
2.96	male	0/10	0/10
	female	0/10	0/10
control	male	0/10	0/10
	female	0/10	0/10
Body weight (g)
Dose (mg/L)	sex	at d 0	after 7 d	after 14 d	Body weight gain (14d; g)
8.78	male	192
	female	181
7.42	male	196	202	231	35
	female	173	184	196	23
6.30	male	182	210	238	56
	female	179	289	192	13
5.35	male	181	218	256	75
	female	180	185	191	11
5.24	male	187	214	247	60
	female	184	187	202	18
2.96	male	188	224	269	81
	female	184	193	209	25
control	male	193	220	249	56
	female	185	200	213	28

Applicant's summary and conclusion

Interpretation of results:

Category 3 based on GHS criteria