Methyl formate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: 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 401 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

no

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Methyl formate

EC Number:

203-481-7

EC Name:

Methyl formate

Cas Number:

107-31-3

Molecular formula:

C₂H₄O₂

IUPAC Name:

methyl formate

Details on test material:

- Name of test material (as cited in study report): Methylformiat
- Physical state: liquid
- Analytical purity: 98%
- Impurities (identity and concentrations): methanol 2%.

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 190-270 G (males) and 180-210 g (females).
- Fasting period before study: 15-20 h 
- Diet: Herilan MRH-Haltung, Eggersmann KG

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 4.64 - 21.5%

MAXIMUM DOSE VOLUME APPLIED: 10 ml/kg bw.

Doses:

464, 681, 1000, 1470, 2150 mg/kg bw

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: after administration, at least daily. Weighing: befor administration and on day 2-4, 7 and 13
- Necropsy of survivors performed: yes
- Other examinations performed: gross pathology of all animals that died

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

ca. 1 500 mg/kg bw

Mortality:

Deaths occurred within 1 hour after dosing at the two highest dose levels (2150 mg/kg bw: 10/10 animals; 1470 mg/kg bw: 4/10).
No deaths occurred in the other dose groups.

Clinical signs:

464 and 681 mg/kg bw:  None;
1000 mg/kg bw:  Dyspnea, apathy, poor condition.
1470 mg/kg bw:  Dyspnea, apathy, stagger, unsteady gait, poor  condition.
2150 mg/kg bw:   Dyspnea, apathy, stagger, unsteady gait, unkempt fur, cyanosis, poor condition, gasps.

Gross pathology:

Animals that died: 
Lungs: rich in blood, edema. Glandular stomach: caustic gastritis. Intestine: softening of the mucosa due to caustic corrosion.
No findings in sacrificed rats.

Any other information on results incl. tables

Symptoms
==========================================================
Dose groups     Symptoms
(mg/kg bw)
----------------------------------------------------------
 464          None
 681          None
1000          Dyspnea, apathy, poor condition.
1470          Dyspnea, apathy, stagger, unsteady gait, poor 
             condition. 
2150          Dyspnea, apathy, stagger, unsteady gait,      
             unkempt fur, cyanosis, poor condition, gasps. 
==========================================================  

Applicant's summary and conclusion

Executive summary:

Conclusion:

The acute oral toxicity of methylformate was examined in a pre-GLP gavage study that was conducted similar to OECD Guideline No.401 using 5 Sprague-Dawley rats per sex per dose. The dose levels tested were 464, 681, 1000, 1470, 2150 mg/kg bw. The observation period was14 days. The combined LD₅₀was approx. 1500 mg/kg bw in this study.