Benzothiazole

Acute Toxicity: inhalation

Administrative data

Endpoint:

acute toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

other information

Study period:

1992

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - Guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Report date:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 403 (Acute Inhalation Toxicity)

Deviations:

no

GLP compliance:

yes

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

Details on test material:

- Name of test material (as cited in study report): Benzothiazol
- Physical state: liquid
- Analytical purity: 97.4 %
- Purity test date: 21.05.1991
- Lot/batch No.: 90 B 0521
- Stability under test conditions: was ensured over the duration of the attempt
- Storage condition of test material: room temperature and under exclusion of light

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: 2-3 month
- Weight at study initiation: 180 - 215 g
- Fasting period before study:
- Housing: 5 per cage (Makrolon Type III)
- Diet: ad libitum (Altromin 1324, Altromin GmbH, Lage, Germany)
- Water: ad libitum
- Acclimation period: 5 days


ENVIRONMENTAL CONDITIONS
- Temperature (°C): 22 ± 2 °C
- Humidity (%): 50 %
- Air changes (per hr): 10 times per hour
- Photoperiod: 12 hrs dark / 12 hrs light

Administration / exposure

Route of administration:

other: inhalation: vapour and aerosol

Type of inhalation exposure:

nose/head only

Vehicle:

not specified

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Aerosol inhalation chamber (PVC)
- Exposure chamber volume: 20 L
- Method of holding animals in test chamber: Exposition tubes (Rhema Labortechnik, Germany)
- Method of conditioning air: 2 in parallel connected Boge-compressors (type SB 270/15/350D) and a connected air-compressor dryer (type A 110)
- System of generating particulates/aerosols: Two-component jet (Rhema Labortechnik, Germany), conditioned compressed air (15 L per minute, 700 kPa) and a pre-separator (Baffle)

- Treatment of exhaust air: Aerosolfilter
- Temperature, humidity, pressure in air chamber: Temperature: 21 - 23 °C; Humidity: ~30 %

TEST ATMOSPHERE
- Brief description of analytical method used: Aeorodynamic particle sizer with laservelocimeter (TSI-APS 3300). The instrument was operated with 2 different dilutions according to Remiarz and Johnson (1984).
- Samples taken from breathing zone: yes


GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Vapour inhalation chamber (stainless stell)
- Exposure chamber volume: 7 L
- Method of holding animals in test chamber: Exposition tubes (Rhema Labortechnik, Germany)
- Source and rate of air: 10 L/min
- System of generating vapour: The test substance was in a wash bottle with frit; the thermo stabilisation (21°C) of the water bath was effected by a thermostat (JULABO UC)

Analytical verification of test atmosphere concentrations:

yes

Duration of exposure:

4 h

Concentrations:

376.5 (vapour), 2360.7 (aerosol) and 6153.9 mg/m³ air (aerosol)

No. of animals per sex per dose:

5

Control animals:

yes

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: before administration, at day 3 and 7 after administration and thereafter 1 time per week
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight

Statistics:

LC50 was calculated according to Rosiello, A.P., Essigmann, J.M. and Wogan, G.N. (1977); modified after Pauluhn (1983)

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LC50

Effect level:

ca. 5 mg/L air

Exp. duration:

4 h

Mortality:

At 6153.9 mg/m³ air: 3/5 male rats and 4/5 female rats

Clinical signs:

other: Control groups and 376.5 mg/m³air: without symptoms At 2360.7 mg/m³: tumbling walk, decreased and increased motility, side-and prone position, decreased and increased respiration, breathing noises, paleness, restricted palpebral fissure At 6153.9 mg/m³: d

Body weight:

No conspicuous findings

Gross pathology:

Sacrificed animals after observation time: turned red lung
Intercurrent deceased animals: turned red expanded lung, lung oedema, hydrothorax, pale kidney, spleen and lung, dark/pale liver, bladder abnormal filled, bloddy-black intestinal content

Any other information on results incl. tables

Acute inhalation toxicity

Group No.	Conc. (mg/m³ air)		Toxicol. Results (m/s/n)	Time of symptoms	Time of death	Particle = 3 µm (%)
	Nomin.	Analyt.
Male rats
1 2 3 4	Air-con. 488 62300 124600	Air-con. 376.5 2360.7 6153.9	0/0/5 0/0/5 0/5/5 3/5/5	-- -- 4h-1d 4h-7d	-- -- -- 0d-1d	n.d. n.d. 55 38
Female rats
1 2 3 4	Air-con. 488 62300 124600	Air-con. 376.5 2360.7 6153.9	0/0/5 0/0/5 0/5/5 4/5/5	-- -- 4h-2d 4h-8d	-- -- -- 0d-2d	n.d. n.d. 55 38

m: number of rats which died; 
n: number of animals in test
s: number of animals with signs of intoxication

The following analytical concentrations were tested: 0.377 mg/l (vapour); 2.36 mg/l (aerosol) and 6.154 mg/l (aerosol)
(analytical aerosol concentration)

LC50 = 5000 mg/m³ air

Applicant's summary and conclusion

Interpretation of results:

harmful

Remarks:

Migrated information Criteria used for interpretation of results: EU

Conclusions:

Classification:
DSD: Xn, R20 Harmful by inhalation
GHS: Acute Inhalation Category 4, H332

Executive summary:

Pauluhn (Bayer AG), 1981

The acute inhalative toxicity of benzothiazole was investigated in study according to OECD guideline 403. Rats were exposed nose/head-only to an atmosphere containing analytical concentrations of 0.377mg/l (vapour); 2.36 mg/l (aerosol) and 6.154 mg/l (aerosol) benzothiazole for 4 hours. Clinical signs of toxicity were related to dose. Control groups and the 376.5 mg/m³air groups were without symptoms. Tumbling walk, decreased and increased motility, side-and prone position, decreased and increased respiration, breathing noises, paleness and restricted palpebral fissure were observed at a concentration of 2360.7 mg/m³ air benzothiazole. The clinical signs at 6153.9 mg/m³ air benzothiazole were decreased and increased motility, restricted palpebral fissure, side position, narcotized, complicated respiration, breathing noises, cyanosis, paleness, red noses and lacrimation. Mortalities occurred at 6153.9 mg/m³ air 4 hours after administration.The calculated LC50 was 5000 mg/m³ air.