A 10-year Follow-up Cohort Study of the Health Effects in Toner-handling Workers.

In this study, we compare the results of a cross-sectional survey and secular changes between toner-handling workers and non-toner-handling workers, focusing on blood tests, urinalysis, respiratory function tests, and chest imaging results as indices of health effects. Of 116 employees who participated in the survey conducted at an office equipment manufacturer in Japan, 65 male employees who could be followed up for 10 years were included in the analysis. Thirty-eight workers engaged in toner-handling operations were considered toner-handling workers, and 27 not engaged in these operations were considered non-toner-handling workers. The blood tests (WBC, CRP, IgE, KL-6, and SP-D), urinalysis (8-OHdG), respiratory function tests (PEFR, VC, %VC, FEV1.0, and FEV1.0%), chest radiography, and chest CT results were compared between both groups. Non-toner-handling workers had significantly higher 8-OHdG/Cre at baseline and KL-6 at year 10 than did toner-handling workers. There were no significant differences between the results of the cross-sectional survey and a longitudinal survey of respiratory function test results. We conclude that there were no adverse health effects due to toner exposure.

The respiratory effects of toner exposure according to long-term occupational toner handling history: A longitudinal analysis, 2004-2013.

OBJECTIVES: This report shows the relationship between toner exposure and respiratory effects for individuals with a longterm occupational toner-handling history, from 2004 to 2013. MATERIAL AND METHODS: Authors studied 752 Japanese male workers in toner handling workshops. A total of 673 men who participated in an annual monitoring survey were analyzed in this study. The following monitoring was performed in the same season each year: personal exposure measurements, biological markers, respiratory function tests, a chest X-ray, chronic respiratory symptoms and incidences of respiratory diseases. To evaluate the toner exposure effect, the exposure categories suitable for each evaluation index were established. RESULTS: For those with an occupational toner-handling history, the mean occupational toner-handling period was 14.36 years (standard deviation = 6.62); one participant had 35 years of exposure, which was the longest and one participant had 1 year of exposure which was the shortest. There were no statistically significant differences in the rate of change of respiratory function tests. An ANOVA conducted on blood and urine test results showed that statistically significantly differences were observed for a few items but all the values were very low and within the standard range. CONCLUSIONS: Authors conducted a 10-year ongoing study, but no obvious negative influences on health were attributed to toner exposure. In a work environment where adequate administrative controls are in place, personal toner exposure levels may be expected to be low, with no adverse effects on human health. Int J Occup Med Environ Health 2018;31(6):809-822.

A 4-Year Follow-up Cohort Study of the Respiratory Functions in Toner-handling Workers.

BACKGROUND: Focusing on the respiratory function for health effect indices, we conducted a cross-sectional study on workers who did and did not handle toner to compare the longitudinal changes. METHODS: Among 116 individuals who worked for a Japanese business equipment manufacturer and participated in the study, the analysis included 69 male workers who we were able to follow up for 4 years. We categorized the 40 workers engaged in toner-handling work as the exposed group and the 29 workers not engaged in these tasks as the referent group, and compared their respiratory function test results: peak expiratory flow rate (PEFR), vital capacity (VC), predicted vital capacity (%VC), forced expiratory volume in 1 second (FEV1), and forced expiratory volume in 1 second as a percent of forced vital capacity (FEV1%). RESULTS: The cross-sectional study of the respiratory function test results at the baseline and at the 5(th) year showed no statistically significant differences in PEFR, VC, %VC, FEV1, and FEV1% between the exposed and referent workers. Also, respiratory function time-course for 4 years was calculated and compared between the groups. No statistically significant differences were shown. CONCLUSION: Our study does not suggest any toner exposure effects on respiratory function. However, the number of subjects was small in our study; studies of larger populations will be desired in the future.

[Continuing investigation of effect of toner and its by-product on human health and occupational health management of toner].

OBJECTIVE: As there are reports that ultrafine particles are generated by thermal printer toner, and that mucosal irritation symptoms were observed in users. When printers were operated, we have been examining the effects of not only toner but its by-products on human health. METHODS: We conducted a review of epidemiological and animal data on toner and its by-products such as ultrafine particles and volatile organic compounds (VOC). This was the second survey and it confirmed the results of the first survey. RESULTS: We reviewed the data, and summarized the results as follows. 1) Four cross-sectional studies reported no definite harmful effects of toner. 2) Ultrafine particles were generated in greater numbers at higher fuser heating and higher toner coverages. Ultrafine particles were also observed at lower rates in idle mode. 3) High-sensitive c-reactive protein in serum and heart rate variability (HRV) were useful biomarkers of not only exposure to ultrafine particles but disorder of cardiovascular disease, 8-hydroxydeoxyguanosine in urine is a biomarker of acute lung injury by welder fume, and VEGF and CA15-3 are highly sensitive and specific biomarkers of pulmonary fibrosis. 4) Physico-chemical properties of ultrafine particles were examined, and specific parameters related to pulmonary responses were not observed. CONCLUSIONS: Taken together, we found that there are some biomarkers which are related to not only exposure and but disorders induced by ultrafine particles, and that the generation of ultrafine particles with the operation of printers was associated with other factors than the fixing process. Until now there has been insufficient data for estimation of the hazards of toner and its by-products. However, continuing examinations are useful for complementing and correcting the information and data on toners and for revising the measures of occupational health. We will continue these examinations of toner and its by-products in the future.