Bis(tributyltin) oxide

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

short-term repeated dose toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

4 (not assignable)

Rationale for reliability incl. deficiencies:

secondary literature

Data source

Reference

Reference Type:

review article or handbook

Title:

Unnamed

Year:

1986

Report date:

1986

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

During inhalation studies with TBTO over 29-32 days (on 5 days/week, i.e. 21-24 treatments) rats were exposed in nose-only chambers over 4 hour periods.

GLP compliance:

not specified

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Bis(tributyltin) oxide

EC Number:

200-268-0

EC Name:

Bis(tributyltin) oxide

Cas Number:

56-35-9

Molecular formula:

C24H54OSn2

IUPAC Name:

tributyl[(tributylstannyl)oxy]stannane

Details on test material:

Reported as Tributyltin oxide (TBTO) , with the synonyms bis (tri-n-butyltin) oxide or hexa-n-butyldistannoxane

Test animals

Species:

rat

Strain:

not specified

Sex:

not specified

Administration / exposure

Route of administration:

other: aerosol or vapour

Type of inhalation exposure:

nose only

Vehicle:

air

Remarks on MMAD:

MMAD / GSD: Aerosol had 90-100% inhalable particles within it

Details on inhalation exposure:

Figure of expemerimental design provided, components included regulator and rotameter for inlet air, washing bottles with test material for generation of aerosol or vapour, particle filter (which was omittede in case of aerosol) wahsing bottle with water for admixture of humid air, nose only exposure chamber 60L volume, regulator and rotameter for exhaust air with washing bottle for removal of test material, temperature and humidity control, absorption washing bottles for determination of actual concentration, optical particle counter.

Analytical verification of doses or concentrations:

yes

Details on analytical verification of doses or concentrations:

Acutal chamber concentration and particle size distribution in the chamber were controlled repeatedly.

Duration of treatment / exposure:

4 h

Frequency of treatment:

5d/wk
21-24 treatments over 29-32 days

Doses / concentrations

Doses / concentrations 1

Dose / conc.:

0.03 mg/m³ air (analytical)

Remarks:

vapour

Doses / concentrations 2

Dose / conc.:

0.16 mg/m³ air (nominal)

Remarks:

vapour

Doses / concentrations 3

Dose / conc.:

2.8 mg/m³ air (analytical)

Remarks:

aerosol

No. of animals per sex per dose:

10/sex

Control animals:

yes, sham-exposed

Positive control:

No information

Results and discussion

Results of examinations

Clinical signs:

effects observed, treatment-related

Description (incidence and severity):

At 2.8 mg/m³ aerosol, 5 males and 6 females died; apathy and respiratory distress was observed

Mortality:

mortality observed, treatment-related

Description (incidence):

At 2.8 mg/m³ aerosol, 5 males and 6 females died; apathy and respiratory distress was observed

Body weight and weight changes:

effects observed, treatment-related

Description (incidence and severity):

At 2.8 mg/m³ aerosol, decreased weight gain

Food consumption and compound intake (if feeding study):

effects observed, treatment-related

Description (incidence and severity):

At 2.8 mg/m³ aerosol, decreased food consumption

Food efficiency:

not specified

Water consumption and compound intake (if drinking water study):

not specified

Ophthalmological findings:

not specified

Haematological findings:

effects observed, treatment-related

Description (incidence and severity):

At 2.8 mg/m³ aerosol, α1-, total α, β-globulin ↓, albumin-globulin ratio ↓)

Clinical biochemistry findings:

not specified

Urinalysis findings:

not specified

Behaviour (functional findings):

not specified

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

effects observed, treatment-related

Description (incidence and severity):

At 2.8 mg/m³ aerosol, inflammatory reactions with the total respiratory tract and lymphotoxic effects

Histopathological findings: non-neoplastic:

not specified

Histopathological findings: neoplastic:

not specified

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

0.16 mg/m³ air (analytical)

Based on:

test mat.

Remarks:

vapour

Sex:

male/female

2

Dose descriptor:

LOAEL

Effect level:

2.8 mg/m³ air (analytical)

Based on:

test mat.

Remarks:

aerosol (90-100% inhalable particles)

Sex:

male/female

Basis for effect level:

body weight and weight gain

clinical biochemistry

clinical signs

food consumption and compound intake

histopathology: non-neoplastic

mortality

Target system / organ toxicity

Critical effects observed:

not specified

Applicant's summary and conclusion

Conclusions:

In rats exposed to the 2.8 mg/m³ aerosol, 11/20 animals died and a decrease in food consumption and weight gain was observed; other effects at this concentration included changes in hematology parameters, inflammatory reactions in the respiratory tract, and lymphotoxic effects. The NOAEL was determined 0.16 mg/m³. The LOAEL was determined to be 2.8 mg/m³.

Executive summary:

In an inhalation study with tributyltin oxide rats were exposed in nose only chambers for 4 hours 5 days a week for 21 -24 treatments for 29 -32 days. The acutal chamber concentration and particle size distribution in the exposure chamber were controlled repeatedly; dose groups included sham exposed animals, 0.03 mg/m³ vapour, 0.16 mg/m³ vapour, and 2.8 mg/m³ aerosol (90 -100% inhalable particles). The higher of the two vapour concentration corresponds to the equilibriium vapour pressure of the test material in the chamber atmosphere and can be regarded as a no-effect level. In rats exposed to the 2.8 mg/m³ aerosol, 11/20 animals died and a decrease in food consumption and weight gain was observed; other effects at this concentration included changes in hematology parameters, inflammatory reactions in the respiratory tract, and lymphotoxic effects. The NOAEL was determined 0.16 mg/m³. The LOAEL was determined to be 2.8 mg/m³.