Reaction mass of 2-methylbutyl acetate and pentyl acetate

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1984

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1984

Report date:

1984

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OPP 81-3 (Acute inhalation toxicity)

Principles of method if other than guideline:

Rats were exposed to primary amyl acetate for 6 hrs using static conditions or 4 hrs using dynamic conditions. Survivors were observed for 14 days following exposure. All rats were subjected to a gross necropsy examination.

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of 2-methylbutyl acetate and pentyl acetate

EC Number:

908-918-1

Molecular formula:

Unspecified

IUPAC Name:

Reaction mass of 2-methylbutyl acetate and pentyl acetate

Details on test material:

The test material is 98.8% pure (all isomers totaled).
Approximate isomeric composition Primary Amyl Acetate: 60%, 2-Methyl Butyl Acetate: 35% and 3-Methyl Butyl Acetate: 5%

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

No additional information available.

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

air

Details on inhalation exposure:

Groups of male and female rats were exposed to primary amyl acetate for 6 hours under static conditions. The test material is enclosed in a sealed 120 liter chamber for approximately 18 hours before the introduction of the rats.

Groups of male and female rats were exposed to primary amyl acetate for 4 hours under dynamic airflow conditions. The test material is metered with an FMI Lab Pump (G-6) into a heated glass evaporator. Air containing vapors of test material were swept at a flow rate of 300 l/m into the chamber which had a volume of Approximately 1330 liters with pyramidal top and bottom.

Monitoring Chamber Concentrations
Dynamic Exposure
The chamber atmosphere was analyzed for amyl acetate isomers approximately once every 8 minutes during the exposure. The mean concentration +/- standard deviation) was 976 (+/- 13.0) ppm. The mean analytical/nominal concentration ratio was 0.98; the nominal concentration being an estimate calculated from the quantity of test material consumed during the exposure and the chamber airflow rate. The concentration ratio of the n-amyl acetate isomer to total amyl acetate isomers in the chamber atmosphere was 58%
.
Static Exposure
The concentration of amyl acetate isomers was determined hourly in each of the two exposure chambers. The females were exposed to a mean concentration of 3628 (+/- 330) ppm and the males to 3693 (+/- 257) ppm. The concentration ratio of the n-amyl acetate isomer to total amyl acetate isomers in the chamber atmosphere was 68%.

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 - 6 h

Concentrations:

976.1 (+/- 13.0) ppm (dynamic airflow conditions)
3628 (+/-330) ppm (static airflow condtions) females
3693 (+/- 257) ppm (static airflow conditions) males

No. of animals per sex per dose:

5 male and 5 female rats (dynamic airflow conditions)
5 male and 5 female rats (static airflow conditions)

Control animals:

not specified

Details on study design:

Rats were exposed for 4 hrs under dynamic conditions to the test material. Animals were observed during exposure and for 14 days following exposure for clinical symptoms. All animals were submitted to a gross pathological examination upon death or the end of the observation period.

Statistics:

Means and standard deviations were calculated.

Results and discussion

Preliminary study:

Not applicable.

Effect levels

Sex:

male/female

Dose descriptor:

LC0

Effect level:

>= 19.28 mg/L air

Based on:

test mat.

Exp. duration:

6 h

Remarks on result:

other: static conditions (original value: 3628 ppm)

Mortality:

There was no mortality in rats exposed under dynamic (4 hr) or static (6 hr) conditions.

Clinical signs:

other: Rats exposed under dynamic condtions (4 hrs at 976 ppm) Group Observations: There were no clinical signs of toxicity. Rats exposed under static conditions (6 hrs at ~3650 ppm) Group Observations:. Forced respiration and hypoactivity during exposure, abno

Body weight:

Rats exposed under dynamic condtions (4 hrs at 976 ppm)
Males gained on average 90 g during the 14 day observation period while females gained 20 g during the same time period.

Rats exposed under static conditions (6 hrs at ~3650 ppm)
Males gained on average 88 g during the 14 day observation period while females gained 10 g during the same time period.

Gross pathology:

There were no grossly visible lesions noted in rats subjected to the test material under dynamic or static conditions.

Other findings:

No additional information available.

Any other information on results incl. tables

No additional information available.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

The results of these studies indicate that the 4- or 6-hour LC50 values for primary amyl acetate are greater than 19.3 mg/L

Executive summary:

The acute inhalation toxicity of primary amyl acetate was examined. In rats exposed (static conditions) to primary amy1 acetate vapor as high as 3600 ppm (~19.3 mg/L) for six hours, no deaths occurred. Signs of toxicity were observed during the exposure, but these signs disappeared shortly after termination of the exposure. Rats exposed under dynamic conditions to 976 ppm for 4 hours also survived the exposure with less visible signs of toxicity.