A cohort study using pulmonary function tests and x-ray examination in toner-handling workers: cross-sectional and longitudinal analyses from 2003 to 2008

OBJECTIVES

This study uses pulmonary function tests and chest x-ray examinations to examine the relationship between toner-handling work and its health effects.

METHODS

The subjects were 1504 male workers in a Japanese toner and photocopier manufacturing company, in the age range from 19 to 50 years in 2003. Personal exposure measurements, pulmonary function tests, chest x-ray examinations, biomarker measurements, and a questionnaire about respiratory symptoms were conducted. The present study reports the results of pulmonary function tests and chest x-ray examinations conducted in the subjects, which includes a cross-sectional study on the toner handling and non-handling workers and a longitudinal study from 2003 to 2008.

RESULTS

Few significant findings were suspected to be caused by toner exposure found in pulmonary function indices in both the cross-sectional and longitudinal studies. Any obvious fibrotic findings in chest x-ray findings related to the toner exposure could not be found out.

CONCLUSION

No evidence of adverse effects on pulmonary function indices and chest x-rays was present in the toner-handling workers as compared to the nonspecifically exposed workers. Although the toner exposure concentration is quite low in the current well-controlled working environment, even among the toner-handling workers, we would like to continue this study in the future to verify the toner exposure health effects.

Analysis and Differentiation of Photocopy Toners

The identification and classification of photocopiers presents particular problems for the document examiner. While comparison of defect marks serves to identify copies produced on an individual office copy machine, it is often necessary to eliminate large numbers of machines as possible sources before commencing this detailed examination. Differentiation of toners offers an effective means of achieving this elimination. This review describes the chemical and physical properties of different toners and how these properties can be used for toner discrimination. The chemical composition of bulk toners is outlined together with assessment of the chemical techniques, infrared spectroscopy, pyrolysis mass spectroscopy and energy dispersive x-ray analysis, which have been successfully applied to the analysis of toners removed from copy papers. The different physical properties of toners on paper are related to both their composition and the methods used to fuse toners to the paper. Simple observations such as color, texture and surface appearance, made visible by low power microscopy, offer much discrimination; more can be achieved from examination of magnetic properties and from the use of scanning electron microscopy to study surface morphology. Finally the effectiveness of each technique is assessed and a sequential approach to toner analysis suggested.