5-(diisopropylamino)-2-[[4-(dimethylamino)phenyl]azo]-3-methyl-1,3,4-thiadiazolium methyl sulphate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 Nov -13 Dec 1988

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1989

Report date:

1989

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

5-(diisopropylamino)-2-[[4-(dimethylamino)phenyl]azo]-3-methyl-1,3,4-thiadiazolium methyl sulphate

EC Number:

281-589-3

EC Name:

5-(diisopropylamino)-2-[[4-(dimethylamino)phenyl]azo]-3-methyl-1,3,4-thiadiazolium methyl sulphate

Cas Number:

83969-12-4

Molecular formula:

C17H27N6S.CH3O4S

IUPAC Name:

4-{2-[(2E)-5-[bis(propan-2-yl)amino]-3-methyl-2,3-dihydro-1,3,4-thiadiazol-2-ylidene]hydrazin-1-ylidene}-N,N-dimethylcyclohexa-2,5-dien-1-iminium methyl sulfate

Test material form:

liquid

Details on test material:

Basic Blue 159 methyl sulfate

Test animals

Species:

rat

Strain:

Wistar

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann, Borchen, Germany
- Age at study initiation: 9 wks (male), 14 wks (female)
- Weight at study initiation: mean 181 g (male), 176 g (female)
- Fasting period before study: 16 h
- Housing: Makrolon Type III cages (group of 5 animals)
- Diet (e.g. ad libitum): ad lib.
- Water (e.g. ad libitum): ad lib.

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20 - 24
- Humidity (%): 40 - 60 rh
- Light/darkness (h): 12/12
- Acclimation period: min. 5 days

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

Application volume: 10 mL/kg bw

Doses:

males: 50, 100, 200, 250, 500, 800 mg/kg bw
females: 50, 100, 200, 250, 310 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 and weighing: daily
- Other examinations performed: clinical signs, body weight, gross pathology

Statistics:

Probit analysis

Results and discussion

Preliminary study:

Probit analysis

Effect levels

Effect levels 1

Sex:

male/female

Dose descriptor:

LD50

Effect level:

216 mg/kg bw

Based on:

test mat.

95% CL:

172 - 272

Effect levels 2

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

124 mg/kg bw

Based on:

act. ingr.

95% CL:

99 - 156

Mortality:

50 mg/kg bw: no mortality
100 mg/kg bw: 0-20%
200 mg/kg bw: 20%
250 mg/kg bw: 80%
310 (female) & 800 (male) mg/kg bw: 100%
Mortality occurred between 1h - 1d after application

Clinical signs:

50 mg/kg bw: no symptoms
100 - 800 mg/kg bw: bad general condition, sedation, prone or later position, bristled fur
200 -800 mg/kg bw: algospams
310 / 800 mg/kg bw: gasping
All symptoms occurred ca. 30 min after application and disappeared until day 2.

Body weight:

Males: no influence
Females: slight growth inhibition from 200 mg/kg bw

Gross pathology:

100 - 800 mg/kg bw: stomach mucosa elapsed, stomach/gut contents reddened and bloated
250 - 800 mg/kg bw: lungs reddened
All survivors from 50 - 500 mg/kg bw were pathologically w/o finding

Applicant's summary and conclusion

Interpretation of results:

Category 3 based on GHS criteria

Conclusions:

The LD50 (oral, gavage) in male and female rats was determined to be 124 mg/kg bw. The substance is classified as Category 3.

Executive summary:

An acute oral toxicity study was carried out with the test item in male and female rats. Five rats/sex/dose groups received a single gavage of the test item dissolved in distilled water at dose levels of 50, 100, 200, 250, 500, 800 mg/kg bw for males and 50, 100, 200, 250, 310 mg/kg bw for females. The animals were observed for signs of toxicity for 14 days thereafter.

Clinical signs observed in animals after a single administration of 100 to 800 mg/kg bw Basic Blue 159 were poor general condition, piloerection, sedation and prone or lateral position. Occasionally, tonic-clonic convulsions, laboured respiration and stilted gait occurred. A slight delay in body weight development was observed in females at a dose of 200 mg/kg bw in the first week of the study. In the pathological-anatomical examination of the deceased male and female rats at doses of 100 to 800 mg/kg bw, non-specific damage to the gastrointestinal tract and in part reddening of the lungs were observed. A dose of 50 mg/kg was tolerated without any clinical signs.

The following deaths were observed during the post-treatment phase:

Dose [mg/kg bw]	No of deaths	Time of death	Mortality rate [%]
males
50	0	-	0
100	0	-	0
200	1	4 h	20
250	4	4-8 h	80
500	4	1 h	80
800	5	2-4 h	100
females
50	0	-	0
100	1	1 h	20
200	1	1 d	20
250	4	4-8 h	80
310	5	4-8 h	100

The resulting oral LD50 for males and females together was calculated to be 216 mg/kg bw (CI 172 to 272 mg/kg bw) based on test material. This calculated to 124 mg/kg bw for the active ingredient.