Retrospective Assessment of Exposure to Chemicals for a Microelectronics and Business Machine Manufacturing Facility

Abstract

A retrospective exposure assessment was performed for use in a health outcomes study of a facility manufacturing circuit boards, business machines, and other equipment during the years 1969–2002. A matrix was developed identifying chemical use by department-year based on company-provided information. Use of six chemical agents (fiberglass, lead, methylene chloride, methyl chloroform, perchloroethylene, and trichloroethylene) and six chemical classes (acid-base, aromatic hydrocarbons, chlorinated hydrocarbons, other hydrocarbons, chlorofluorocarbons, and metals), and general (including unspecified) chemicals was identified. The matrix also contained an assignment for each department-year categorizing the potential for use of chemicals as negligible, intermittent/incidental, or routine. These department-based exposure matrix data were combined with work history data to provide duration of potential chemical use for workers. Negligible, intermittent/incidental or routine extent-of-chemical-use categories comprised 42.6%, 39.4%, and 17.9%, respectively, of total person-years of employment. Cumulative exposure scores were also developed, representing a relative measure of the cumulative extent of potential exposure to the six chemical agents, six chemical classes, and general (including unspecified) chemicals. Additionally, the study period was divided into manufacturing eras showing trends in chemical use, and showing that process use of trichloroethylene and methylene chloride ended in the mid-1980s and the mid-1990s, respectively. This approach may be useful in other assessments addressing a variety of chemicals, and with data constraints common to retrospective chemical exposure studies.

KEYWORDS:

• occupational exposure
• circuit board manufacture
• substrate production
• exposure matrix
• exposure score
• chlorinated solvents
• trichloroethylene
• perchloroethylene

ACKNOWLEDGMENTS

The authors wish to acknowledge the assistance of numerous members of the NIOSH Industry-wide Studies Branch who were instrumental in the planning and conduct of the site visits to collect company data; to organize, review, and store records; and to facilitate this work. In particular we wish to recognize Chris Gersic, Jean Geiman, Denise Giglio, Delores Montgomery, Surprese Watts, Faith Armstrong, Bill Ehling, and Kim Jenkins for data capture and coding. Kevin L. Dunn assisted in the document reviews, Steve Allee provided programming assistance, and Lynne Pinkerton provided consulting on the overall study and objectives. Funding for this research was provided by the National Institute for Occupational Safety and Health.