Systematic Literature Review of Uses and Levels of Occupational Exposure to Tetrachloroethylene

Abstract

Tetrachloroethylene has been one of the most widely used chlorinated solvents in the United States. This review provides a basis for tetrachloroethylene exposure assessment in population-based case-control studies. We performed literature searches in MEDLINE, TOXLINE, NIOSHTIC, and the NIOSH Health Hazard Evaluation databases using relevant search terms. We calculated weighted arithmetic means from the measurement data and compiled these into three summary tables by type of operation: (1) dry cleaning, (2) degreasing, and (3) other operations. We identified 258 relevant documents, of which 179 (69%) contained useful descriptive information. Within the dry cleaning industry, the overall arithmetic mean (AM) for personal tetrachloroethylene exposures was 59 ppm (range: 0–4636, n = 1395). Machine operators who transferred wet garments to a dryer had the highest levels (AM = 150 ppm [range: 0–1000, n = 441]) of the jobs in this industry. The AM for personal measurements associated with degreasing was 95 ppm (range: 0–1800, n = 206). In addition, we identified several other sources of substantial tetrachloroethylene exposure, including cleaning mining equipment, testing coal, cleaning animal coats in taxidermy, and cleaning and duplicating film. Exposure assessment in population-based, case-control studies is a complex process requiring substantial resources. Researchers conducting these types of studies will be able to use results of the measurements to quantify tetrachloroethylene exposure levels for various jobs.

Keywords:

• case control study
• chlorinated solvents
• degreasing
• dry cleaning
• exposure assessment

Acknowledgments

This research was funded in part by grant T42 OH008433-03 from the National Occupational Research Agenda (NORA).

Notes

^A N = number of measurements. The number of measurements in specific categories may not add up to the number in the more general categories because of missing information on job title, duration, or type of sample.

^B AM and GSD may have been reported in publication or may have been calculated.

^C Range not given.

^A N = number of measurements. The number of measurements in specific categories may not add up to the number in the more general categories because of missing information on job title, duration, or type of sample.

^B AM and GSD may have been reported in publication or may have been calculated.

^C Range not given.

^A N = number of measurements. The number of measurements in specific categories may not add up to the number in the more general categories because of missing information on job title, duration, or type of sample.

^B AM and GSD may have been reported in publication or may have been calculated.

^C Range not given.

^A AM and GSD may have been reported in publication or may have been calculated.

^B Measurement was less than LOD.

^C Measurements taken at the request of employees or union because of health concerns.

^D Year of measurement estimated as 1 year prior to publication.