2-chlorobuta-1,3-diene

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

chronic toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Published GLP study conducted for the National Toxicology Program

Cross-reference

Reason / purpose for cross-reference:

reference to same study

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1998

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

other: OECD Guideline 451 (Carcinogenicity Studies)

GLP compliance:

yes

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

2-chlorobuta-1,3-diene

EC Number:

204-818-0

EC Name:

2-chlorobuta-1,3-diene

Cas Number:

126-99-8

Molecular formula:

C4H5Cl

IUPAC Name:

2-chlorobuta-1,3-diene

Details on test material:

The chemical, a clear colorless liquid, was identified as chloroprene by infrared, ultraviolet/visible, and nuclear magnetic resonance spectroscopy and by boiling point and density. The overall purity was determined to be approximately 96%.

For further details see cross reference to same study in chapter carcinogenicity

Test animals

Species:

rat

Strain:

Fischer 344

Sex:

male/female

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

other: nitrogen

Analytical verification of doses or concentrations:

yes

Duration of treatment / exposure:

6 hours per day, 5 days per week, for 105 weeks; for further information see chapter carcinogenicity

Frequency of treatment:

Daily, 5 days per week

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 12.8, 32 or 80 ppm
Basis:
nominal conc.

No. of animals per sex per dose:

50 rats/sex/group

Control animals:

yes, sham-exposed

Results and discussion

Effect levels

Dose descriptor:

LOAEC

Effect level:

12.8 ppm

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: the incidence of non-neoplastic lesions of the lungs (bronchiolar hyperplasia or alveolar epithelia hyperplasia) and of the nose (chronic inflammation; atrophy or necrosis) were increased

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

In this 2-year chronic inhalation bioassays conducted by NTP (1998), the incidence of non-neoplastic lesions of the lungs (bronchiolar hyperplasia or alveolar epithelia hyperplasia) and of the nose (chronic inflammation; atrophy or necrosis) were statistically increased in rats treated at the lowest exposure concentration in the study (12.8 ppm). a No-Observed-Adverse-Effect-Concentration (NOAEC) was not identified in the study.

For further details and neoplastic observations see cross reference to same study in chapter carcinogenicity.

Applicant's summary and conclusion

Conclusions:

In this 2-year chronic inhalation bioassays conducted by NTP (1998), the incidence of non-neoplastic lesions of the lungs (bronchiolar hyperplasia or alveolar epithelia hyperplasia) and of the nose (chronic inflammation; atrophy or necrosis) were statistically increased in rats treated at the lowest exposure concentration in the study (12.8 ppm). a No-Observed-Adverse-Effect-Concentration (NOAEC) was not identified in the study.