State of Toner Exposure of Workers Who Handle Toners

Abstract

The aim of this study was to ascertain the actual state of toner exposure of workers who handle toner. Personal exposure measurements were conducted on workers handling toner in which the respirable dust (RD) concentration by work type was determined. Targeted work types consisted of "machine recycling", "toner manufacturing", "toner research/development", "machine design/development" and "servicing." The implementation period lasted from April 2003 to March 2011, and measurements were conducted annually. The measurement method conformed to the Japanese Working Environment Measurement Standards (new standards adopted starting in 2005). Comparing the RD concentrations for fiscal year 2003 by work, significant differences were found between machine recycling and the other four work types, as well as in toner manufacturing and the other four work types. Similarly, based on the new legislative standards applied in Japan from fiscal year 2005, significant differences were found between machine recycling and the other four work types, as well as in toner manufacturing and the other four work types. It is clear that workers engaged in machine recycling and toner manufacturing are exposed to toner, and that a certain level of exposure is continuing. Although it cannot be said that workers involved in toner research/development, machine design/development and servicing have no toner exposure, the concentration is of an extremely low level. At present, toner exposure levels by work type can be divided into two groups-one consisting of machine recycling and toner manufacturing, and the other consisting of toner research/development, machine design/development and servicing.