Registration Dossier

Toxicological information

Exposure related observations in humans: other data

Administrative data

Endpoint:
exposure-related observations in humans: other data
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study well documented, meets generally accepted scientific principles, acceptable for assessment Accepted calculation method

Data source

Referenceopen allclose all

Reference Type:
publication
Title:
The identification of effluents from rubber vulcanization / Environ. Aspects Chem. Use Rubber Process. Oper., Conf. Proc.
Author:
Rappaport SM
Year:
1975
Bibliographic source:
U.S. EPA - Office of Toxic Substances, Washington (D.C. USA)
Reference Type:
publication
Title:
Air sampling and analysis in a rubber vulcanization area
Author:
Rappaport SM and Fraser DA
Year:
1977
Bibliographic source:
Am. Ind. Hyg. Assoc. J. 38, 5, 205-210
Reference Type:
publication
Title:
Health aspects of the curing of synthetic rubbers
Author:
Fraser DA and Rappaport S
Year:
1976
Bibliographic source:
Environ. Health Perspect. 17, 45-53

Materials and methods

Endpoint addressed:
other: exposure to airborne concentration in rubber vulcanization industry during rubber stock curing process
Principles of method if other than guideline:
details: see publication

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
other: vapor and airborne concentrations in the occupational environment during curing of rubber stock

Method

Details on study design:
-quantitative and qualitative analysis by using gas chromatograhy coupled with mass spectrometry
generating vulcanization effluents from a stock in the lab (representative for a typical formulation cured by all major rubber companies)
-generation/collection of volantiles: 50g uncured rubber purged with nitrogen in stainless steel curing vessel, curing time 20 min, n=14 at temperatures 160°C -200°C (10°C steps); adsorption of released volantiles on activated charcoal
-sample elution from charcoal with 1 ml ethyl ether; eluate volumen reduced unter nitrogen to 50-75 µl
-2 nd part of the experiment: field air samples collected in the manufacturing area by using charcoal tube method; personnel sampling pumps were used and attached to structures of the locations; samples collected in a press room; 9 samples collected for 15-, 30-, and 45 minute intervalls over 6 hours (flow rate 1-1.5l/min)
Exposure assessment:
measured

Results and discussion

Results:
Concentration of 4-vinyl 1-cyclohexene (mean / std. dev. (rel. std. dev.)) in the occupational environment during curing of rubber stock:
-Location 1: 71.0 ppb / 8.42 ppb (11.9%)
-Location 2: 92.3 ppb / 19.9 ppb (21.6%)

Any other information on results incl. tables

- acute effects have not been observed among employees (Fraser et al, 1976)

Applicant's summary and conclusion

Conclusions:
Conclusion from the publications: On the basis of current toxicological data, chronic health effects are also questionable at these exposure levels, but little information is available concerning the carcinogenic potential of the investigated compounds. Thus significant health effects cannot be ruled out.
Executive summary:

4-vinyl 1-cyclohexene was measured in the air by using gas chromatograhy coupled with mass spectrometry in the occupational environment during curing of rubber stock. The authors came to the conclusion that on the basis of current toxicological data, chronic health effects are also questionable at these exposure levels, but little information is available concerning the carcinogenic potential of the investigated compounds. Thus significant health effects cannot be ruled out.