2-methoxy-2-methylheptane

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 Nov 2017 - 30 Nov 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Appendix to Director General Notification, No. 12-Nousan-8147

Version / remarks:

Appendix to Director General Notification, No. 12-Nousan-8147. Agricultural
Production Bureau, Ministry of Agriculture, Forestry and Fisheries of Japan (JMAFF),
November 2000, including the most recent revisions.

GLP compliance:

yes (incl. QA statement)

Test type:

acute toxic class method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2-methoxy-2-methylheptane

EC Number:

816-311-7

Cas Number:

76589-16-7

Molecular formula:

C9H20O

IUPAC Name:

2-methoxy-2-methylheptane

Test material form:

liquid

Specific details on test material used for the study:

Chemical name (IUPAC), synonym or trade name:2-Methoxy-2-methylheptane
CAS number: 76589-16-7
Appearance: Colorless liquid
Test item storage: At room temperature

Test animals

Species:

rat

Strain:

Wistar

Sex:

female

Details on test animals or test system and environmental conditions:

Species: Rat
Strain: Crl: WI(Han)
Condition: Outbred, SPF-Quality
Number of Animals: 6 Females (nulliparous and non-pregnant). Each dose group consisted of 3 animals.
Age at the Initiation of Dosing: Young adult animals (approximately 8 weeks old) were selected.
Weight at the Initiation of Dosing: 136 to 154 g.
Housing: polycarbonate cages containing sterilized sawdust as bedding material
Acclimation: 5 days
Temperature: 21°C
Humidity: 48 to 51%
Photoperiod: hour light/12-hour dark cycle
Air change: ten or greater air changes per hour with 100% fresh air (no air recirculation)
Food: Pelleted rodent diet, ad libitum
Water: ad libitum
Animal Enrichment: provided with paper

Administration / exposure

Route of administration:

oral: gavage

Details on oral exposure:

A single dose of test item was administered to the appropriate animals by oral gavage on Day 1, using a syringe with a plastic gavage cannula attached.
Animals were deprived of food overnight (for a maximum of 20 hours) prior to dosing and until 3-4 hours after administration of the test item. Water was available.

Doses:

2000 mg/kg

No. of animals per sex per dose:

3 females

Control animals:

no

Details on study design:

The toxicity of the test item was assessed by stepwise treatment of groups of 3 females. The absence or presence of mortality of animals dosed at one step determined the next step, based on the test procedure defined in the guidelines. The onset, duration and severity of the signs of toxicity were taken into account for determination of the time interval between the dose groups. The first group was treated at a dose level of 2000 mg/kg. Based on the results, one additional group was dosed at 2000 mg/kg.
The oral route was selected as it is a possible route of human exposure during manufacture, handling or use of the test item.

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 2 000 mg/kg bw

Based on:

test mat.

Mortality:

One animal was killed in extremis on Day 2. No further mortality occurred.

Clinical signs:

Lethargy, hunched posture, uncoordinated movements, piloerection and/or salivation were
noted for the surviving animals between Days 1 and 3.
Lethargy, flat or hunched posture, uncoordinated movements, labored respiration, piloerection, salivation, watery discharge from the right eye and ptosis were noted for the animal killed in extremis.

Body weight:

The body weight gain shown by the surviving animals over the study period was considered to be similar to that expected for normal untreated animals of the same age and strain.

Gross pathology:

No abnormalities were found at macroscopic post mortem examination of the animals.

Other findings:

See attachment

Applicant's summary and conclusion

Interpretation of results:

Category 5 based on GHS criteria

Conclusions:

The oral LD50 value of the test item in Wistar rats was established to exceed 2000 mg/kg body weight.
According to the OECD 423 test guideline, the LD50 cut-off value was considered to be 2500 mg/kg body weight.
Based on these results:
 according to the Globally Harmonized System of Classification and Labelling of Chemicals (GHS) of the United Nations (2015) (including all amendments), the test substance should be classified as: may be harmful if swallowed (Category 5) for acute toxicity by the oral route.
 according to the Regulation (EC) No 1272/2008 on classification, labelling and packaging of items and mixtures (including all amendments), the test substance does not have to be classified and has no obligatory labelling requirement for oral toxicity.