Benzothiazole

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1982

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to guideline study with acceptable restrictions

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1982

Report date:

1982

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

: lack of details on test substance

GLP compliance:

no

Test type:

standard acute method

Test material

Test material information

Constituent 1

Reference substance name:

Benzothiazole

EC Number:

202-396-2

EC Name:

Benzothiazole

Cas Number:

95-16-9

Molecular formula:

C7H5NS

IUPAC Name:

benzothiazole

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Winkelmann, Borchen, Germany
- Age at study initiation: 9 weeks
- Weight at study initiation: 175 g
- Fasting period before study: 16 hours before and 4 hours after application
- Housing: 5 per cage (Makrolon cages type III)
- Diet: ad libitum (Altormin R 1324, Altromin GmbH, Lage, Germany)
- Water: ad libitum


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 1.5 °C
- Humidity (%): 60 ± 5 %
- Photoperiod (hrs dark / hrs light): 12 hrs dark / 12 hrs light

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

no data

Doses:

Male rats: 0.1, 0.18, 0.2, 0.23, 0.25, 0.3 ml/kg bw
Female rats: 0.1, 0.13, 0.15, 0.16, 0.18 ml/kg bw

No. of animals per sex per dose:

10

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: 2 times per day (observation) and weighing of survivors 14 days after administration
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

LD50 was calculated by Probit-analysis (Fink and Hund 1965. Arzneim.-Forsch. 15:624).

Results and discussion

Effect levels

Effect levels 1

Sex:

male

Dose descriptor:

LD50

Effect level:

257 mg/kg bw

Effect levels 2

Sex:

female

Dose descriptor:

LD50

Effect level:

178 mg/kg bw

Mortality:

Males:
0.18 ml/kg bw: 3/10 animals died 8-24 hours after application
0.2 ml/kg bw: 4/10 animals died 4-24 hours after application
0.23 ml/kg bw: 6/10 animals died 8-24 hours after application
0.25 ml/kg bw: 9/10 animals died 2-8 hours after application
0.3 ml/kg bw: 10/10 animals died 2-24 hours after application

Females:
0.13 ml/kg bw: 3/10 animals died 8-24 hours after application
0.15 ml/kg bw: 6/10 animals died 4 hours - 4 days after application
0.16 ml/kg bw: 8/10 animals died 4 hours - 9 days after application
0.18 ml/kg bw: 10/10 animals died 2 hours - 3 days after application

Clinical signs:

other: paralysis of the rear extremities, bloody tears, narcosis, prone-/ side position, decreased weight and reduced general condition

Gross pathology:

no conspicuous findings

Any other information on results incl. tables

Acute oral toxicity

Dose (ml/kg bw)	Time of death	Dead	Symptoms	Number of rats used
Male rats
0.1 0.18 0.2 0.23 0.25 0.3	8-24 h 4-24h 8-24h 2-8h 2-24h	0 3 4 6 9 10	10 10 10 10 10 10	10 10 10 10 10 10
Female rats
0.1 0.13 0.15 0.16 0.18	8-24h 4h-4d 4h-9d 2h-3d	0 3 6 8 10	10 10 10 10 10	10 10 10 10 10

Male rats: LD50 = 0.206 ml/kg; density: 1.246 g/l; (= 257 mg/kg bw)

Female rats: LD50 = 0.142 ml/kg; density: 1.246 g/l; (= 177 mg/kg bw)

Applicant's summary and conclusion

Interpretation of results:

toxic

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Classification:
DSD: T, R25 Toxic if swallowed
GHS: Acute Oral Category 3, H301

Executive summary:

Loeser, E. (Bayer AG), 1982

The acute oral toxicity of benzothiazole was investigated in male and female SPF rats. 6 male and 5 female groups of 10 animals were dosed with 0.1, 0.18, 0.2, 0.23, 0.25, 0.3 ml/kg bw and 0.1, 0.13, 0.15, 0.16, 0.18 ml/kg bw benzothiazole per gavage and observed for 14 days following exposure for mortality and clinical signs. Mortalities occurred at dose levels equal to and exceeding 0.18 ml/kg bw between 8 and 24 hours after administration in male rats and in female rats at dose levels equal to and exceeding 0.13 ml/kg bw between 8 and 24 hours.

Clinical signs like paralysis of the rear extremities, bloody tears, narcosis, prone-/ side position, decreased weight and reduced general condition were observed.

The calculated LD50 for male rats was 0.206 ml/kg bw (=257 mg/kg bw) and 0.142 ml/kg bw (= 177 mg/kg bw) for female rats.