Chlorodifluoromethane

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:

other: Only short abstract available

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1983

Materials and methods

Test guideline

Qualifier:

no guideline available

Principles of method if other than guideline:

not reported

GLP compliance:

yes

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Chlorodifluoromethane

EC Number:

200-871-9

EC Name:

Chlorodifluoromethane

Cas Number:

75-45-6

Molecular formula:

CHClF2

IUPAC Name:

chlorodifluoromethane

Details on test material:

not available

Test animals

Species:

mouse

Strain:

Swiss

Sex:

male/female

Details on test animals or test system and environmental conditions:

Alderly Park Swiss Mice

Administration / exposure

Route of administration:

inhalation: gas

Type of inhalation exposure:

not specified

Vehicle:

air

Remarks on MMAD:

MMAD / GSD: not available

Details on inhalation exposure:

no details

Analytical verification of doses or concentrations:

not specified

Details on analytical verification of doses or concentrations:

not available

Duration of treatment / exposure:

83 weeks (female), 91 weeks (male)

Frequency of treatment:

5 hr/d, 5d/wk

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 1000, 10,000, 50,000 ppm
Basis:
nominal conc.

No. of animals per sex per dose:

80

Control animals:

yes

Details on study design:

Eighty male and eighty female Alderley Park Swiss mice per group were exposed to concentrations of 0, (two groups) 1000, 10,000 or 50,000 ppm (0, 3500, 35,000, 175,000 mg/m3) chlorodifluoromethane, 5 hr/d, 5 d/wk for up to 83 weeks (females) and 94 weeks (males).

Positive control:

not reported

Examinations

Observations and examinations performed and frequency:

At week 38, 10 mice per group were killed in order to perform blood and biochemical assays including red and white blood cell measurements, platelet count, prothrombin and kaolin-cephalin clotting times and bone marrow examination. Plasma ALT (alanine transaminase) and AST (aspartate transaminase) activity as well as urine analyses were also undertaken.

Sacrifice and pathology:

not details reported

Other examinations:

not reported

Statistics:

not reported

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

no effects observed

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

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

not examined

Ophthalmological findings:

not examined

Haematological findings:

no effects observed

Clinical biochemistry findings:

no effects observed

Urinalysis findings:

no effects observed

Behaviour (functional findings):

effects observed, treatment-related

Description (incidence and severity):

hyperactivity at 50,000 ppm chrlodifluoromethane

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

not examined

Histopathological findings: non-neoplastic:

no effects observed

Histopathological findings: neoplastic:

no effects observed

Details on results:

The only consistent finding was hyperactivity in male mice exposed to 50,000 ppm chlorodifluoromethane. No effects were noted on mortality, body weight gain, haematology and biochemistry nor in histopathology. The No Observed Adverse Effect Concentration (NOAEC) for chlorodifluoromethane in this study was 10,000 ppm (35,000 mg/m3).

Effect levels

Dose descriptor:

NOAEL

Effect level:

10 000 ppm

Based on:

test mat.

Sex:

male/female

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

not available

Applicant's summary and conclusion

Executive summary:

Eighty male and eighty female Alderley Park Swiss mice per group were exposed to concentrations of 0, (two groups) 1000, 10,000 or 50,000 ppm (0, 3500, 35,000, 175,000 mg/m3) chlorodifluoromethane, 5 hr/d, 5 d/wk for up to 83 weeks (females) and 94 weeks (males). The only consistent finding was hyperactivity in male mice exposed to 50,000 ppm chlorodifluoromethane. No effects were noted on mortality, body weight gain, haematology and biochemistry nor in histopathology. The No Observed Adverse Effect Concentration (NOAEC) for chlorodifluoromethane in this study was 10,000 ppm (35,000 mg/m3).