1,1-dimethylheptanethiol

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Not reported

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: This study is classified as reliable with restrictions because although it is pre-GLP, it meets generally accepted scientific standards, is well documented, and acceptable for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1977

Report date:

1977

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

no

Test type:

fixed dose procedure

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

1,1-dimethylheptanethiol (CAS # 25360-10-5)

IUPAC Name:

1,1-dimethylheptanethiol (CAS # 25360-10-5)

Details on test material:

- Name of test material (as cited in study report): t-nonyl mercaptan (1,1-dimethylheptanethiol); purity not noted
- Substance type: Heavy Mercaptan

Test animals

Species:

rat

Strain:

other: WBS/W

Sex:

male

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Weight at study initiation: 200 ± grams

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Doses:

3536, 5000, 7071 or 10,000 mg/kg body weight

No. of animals per sex per dose:

5

Control animals:

no

Details on study design:

- Duration of observation period following administration: 7 days
- Frequency of observations and weighing: daily
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, histopathology

Results and discussion

Effect levels

Sex:

male

Dose descriptor:

LD50

Effect level:

5 550 mg/kg bw

Based on:

test mat.

95% CL:

>= 4 456 - <= 6 909

Remarks on result:

other: Based on significant mortality observed at higher doses

Mortality:

Rats administered a dose of 3536 mg/kg experienced no mortality. Those receiving a dose of 5000 mg/kg experienced a 40% mortality rate. Those receiving a dose of 7071 mg/kg experienced a 80% mortality rate. Those receiving a dose of 10000 mg/kg experienced a 100% mortality rate.

Clinical signs:

other: Motor inactivity, disorientation, and lack of coordination were observed at 24 and 48 hours for all groups.

Gross pathology:

Autopsies revealed probable hepatic and renal pathology.

Any other information on results incl. tables

Results:

Oral Dose (mg/kg)	No. of rats (dead/total)	Mortality	Time for death (days)
3536	0/5	0%	- - - - -
5000	2/5	40%	- - - 2, 3
7071	4/5	80%	-, <1, 2, 3, 5
10000	5/5	100%	<1, <1, <1, 2, 2
LD 50 = 5550 mg/kg (4456-6909) = 95% confidence limit

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

The LD50 was determined to be 5550 mg/kg.

Executive summary:

In an acute oral toxicity study, groups of male WBS/W rats (5/dose) were orally administered (via gavage) a single dose of 1,1-dimethylheptanethiol at 3536, 5000, 7071, or 10,000 mg/kg bw. Animals were subsequently observed for a period of 7 days.

 

Motor inactivity, disorientation, and lack of coordination were observed at 24 and 48 hours for all groups. Body weight losses were observed for several days among survivors, but recovery was observed 5 or 6 days after treatment. Autopsies revealed probable hepatic and renal pathology. 40% mortality was observed at 5000 mg/kg; 80% at 7071 mg/kg; and 100% mortality was observed in rats that received 1,1-dimethylheptanethiol at 10,000 mg/kg bw. The oral LD₅₀ in male rats was determined to be 5550 mg/kg.

 

This study received a Klimisch score of 2 and is classified as reliable with restrictions. Although the study is pre-GLP, it meets generally accepted scientific standards, is well documented, and considered acceptable for assessment.