Dichlorodifluoromethane

Developmental toxicity / teratogenicity

Administrative data

Endpoint:

developmental toxicity

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

Not specified

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Data source

Reference

Reference 1

Reference Type:

review article or handbook

Title:

Fluorocarbons in question

Author:

Paulet G.

Year:

1976

Bibliographic source:

European journal of toxicology and environmental hygiene. Journal europeen de toxicology. 9(7 Suppl):385-407

Reference 2

Reference Type:

review article or handbook

Title:

Toxicity of selected drinking water contaminants

Author:

Safe Drinking Water Committee

Year:

1989

Bibliographic source:

National Research Council. Drinking Water and Health. Volume 3. Washington, DC: National Academy Press, 1989.

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Summary only.

GLP compliance:

not specified

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Dichlorodifluoromethane

EC Number:

200-893-9

EC Name:

Dichlorodifluoromethane

Cas Number:

75-71-8

Molecular formula:

CCl2F2

IUPAC Name:

dichlorodifluoromethane

Test material form:

not specified

Details on test material:

Dichlorodifluoromethane (CFC-12) is a relatively inert, non-flammable liquid that is used mainly as a refrigerant. Its molecular weight is 120.92, its vapor pressure is 6.43 atm at 25°C, and it is quite insoluble in water (5.7 ml/100 ml at 26°C).

Test animals

Species:

rat

Strain:

Wistar

Details on test animals or test system and environmental conditions:

pregnant females

Administration / exposure

Route of administration:

inhalation

Type of inhalation exposure (if applicable):

not specified

Vehicle:

air

Details on exposure:

Not specified

Analytical verification of doses or concentrations:

not specified

Details on mating procedure:

Animals inseminated

Duration of treatment / exposure:

Rats: gestation day 4 to 16

Frequency of treatment:

2 hours per day.

Duration of test:

Half of the Rats were sacrificed on day 20 of gestation, the rest were allowed to deliver

Doses / concentrations

Dose / conc.:

200 000 ppm (nominal)

Remarks:

eq. to 20% concentration of a mixture of CFC-11 (10%) and CFC-12 (90%) in air
(i.e., approx. 180000 ppm CFC-12)

No. of animals per sex per dose:

20 female rats

Control animals:

not specified

Details on study design:

Inseminated Wistar albino rats were administered a mixture of 90% CFC-12 (dichlorodifluoromethane) and 10% Freon 11 by inhalation for 2hr/day. Pregnant rats were exposed on days 4 to 16 of gestation. The mixture was administered in a 20% concentration (200,000 ppm).

Examinations

Maternal examinations:

DETAILED CLINICAL OBSERVATIONS: no data

BODY WEIGHT: Yes

Ovaries and uterine content:

Not specified

Fetal examinations:

Yes, but no details provided

Results and discussion

Results: maternal animals

General toxicity (maternal animals)

Clinical signs:

not specified

Mortality:

not specified

Body weight and weight changes:

no effects observed

Maternal developmental toxicity

Number of abortions:

no effects observed

Pre- and post-implantation loss:

no effects observed

Total litter losses by resorption:

not specified

Early or late resorptions:

no effects observed

Dead fetuses:

no effects observed

Changes in pregnancy duration:

not specified

Details on maternal toxic effects:

Maternal toxic effects: no effects

Effect levels (maternal animals)

Key result

Dose descriptor:

NOEC

Effect level:

> 200 000 ppm (nominal)

Based on:

test mat.

Remarks:

(mixture of 10% CFC-11 and 90% CFC-12)

Remarks on result:

not determinable due to absence of adverse toxic effects

Maternal abnormalities

Key result

Abnormalities:

no effects observed

Results (fetuses)

Fetal body weight changes:

no effects observed

Reduction in number of live offspring:

no effects observed

Description (incidence and severity):

No effects on survival at birth

Changes in sex ratio:

not specified

Changes in litter size and weights:

no effects observed

Changes in postnatal survival:

no effects observed

Description (incidence and severity):

No effects on survival after 1 and 4 weeks

External malformations:

no effects observed

Description (incidence and severity):

No details on examinations performed

Details on embryotoxic / teratogenic effects:

Embryotoxic / teratogenic effects: no effects reported.
Limited details available on teratogenicity examination.

Effect levels (fetuses)

Key result

Dose descriptor:

NOEC

Effect level:

>= 200 000 ppm

Based on:

test mat.

Basis for effect level:

other: No embryotoxicity or fetotoxicity observed at that concentration

Remarks on result:

not determinable due to absence of adverse toxic effects

Fetal abnormalities

Abnormalities:

no effects observed

Description (incidence and severity):

(limited details available)

Overall developmental toxicity

Key result

Developmental effects observed:

no

Any other information on results incl. tables

No indications of any embryotoxic, fetotoxic, or teratogenic changes were found when dams were sacrificed and foetuses removed on day 20 of gestation (rats).

Applicant's summary and conclusion

Conclusions:

No indications of any embryotoxic, fetotoxic, or teratogenic changes were found in the offspring of rats exposed during gestation days 4 to 16.

Executive summary:

In studies of inseminated Wistar albino rats, Paulet et al. (1974) administered a mixture of 90% CFC-12 (dichlorodifluoromethane) and 10% Freon 11 by inhalation for 2hr/day. Rats were exposed on days 4 to 16 of gestation. The mixture was administered in a 20% concentration (200,000 ppm). No indications of any embryotoxic, fetotoxic, or teratogenic changes were found when dams were sacrificed and foetuses removed on day 20 of gestation (rats). No classification is applicable.