BackgroundLittle epidemiological evidence exists regarding the chronic respiratory effects of inhaled powdered toner exposure in humans, although several case reports have suggested the existence of lung disorders that might be related to exposure to toner dust.ObjectiveWe aimed to estimate the chronic health risk to humans associated with routine toner dust exposure in copier industry workers under current actual work conditions.DesignA prospective observational cohort study of occupational population.MethodsChanges in chest radiogram, spirometry measurements and serum and urine biomarkers of biomedical responses to extrinsic stress, as well as subjective symptoms were longitudinally observed for up to 10 years in Japanese copier industry workers responsible for the manufacturing, maintenance or recycling of powdered toner or toner-using machines. A total of 694 subjects who did not change their work category during the follow-up and were free from chronic respiratory diseases at the baseline survey provided reliable results on at least three survey occasions during 3 years or more of follow-up.ResultsTypical fibrosis findings associated with pneumoconiosis was not observed on chest radiograms. No significant differences associated with toner exposure were noted in the frequency of new incidence of either non-specific findings on chest radiogram or serum fibrosis biomarkers (sialylated carbohydrate antigen KL-6 and surfactant protein D). However, the exposed subjects tended to show increases in the frequency of respiratory symptoms and reduced spirometry results during the follow-up compared with the control group, although significant differences were only seen in chronic cough.ConclusionsUnder the current reasonably controlled work environmental conditions, lung fibrotic changes caused by inhaled dust exposure, including powdered toner, appear to be relatively uncommon; however, non-specific temporal irritation causing subjective symptoms and inflammatory responses might exist.

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Objectives In this study, we aimed to establish a method for quantifying bromide ions (Br − ) in blood and urine using gas chromatograph‐mass spectrometer (GC‐MS) equipped with a headspace sampler, for biological monitoring of workers exposed to methyl bromide. Methods Samples were mixed with dimethyl sulfate, and Br − ions were detected using GC‐MS with a headspace sampler. The validity of the proposed method was evaluated based on most of the US FDA guidance. The values obtained were compared with reference values by analysis using Seronorm TM Trace Elements Whole Blood L‐1 RUO. Results The calibration curve showed good linearity in the Br − concentration range of 0.1−20.0 mg/L, and the coefficient of determination R 2 value was >.999. Intraday and interday accuracy values were 99.3%−103.1% and 97.4%−101.8%, respectively. The measured and reference values of Seronorm were concordant. Herein, eight urine and serum samples of workers were analyzed; the samples' Br − concentrations were known. The correlation coefficients of urine and serum samples were 0.97 and 0.96, respectively, and results were consistent. Conclusions This study established a simple and rapid method for the determination of Br − concentration in biological samples using GC‐MS with a headspace sampler. Moreover, it can be used for biological monitoring of occupational exposure to methyl bromide and for the determination of Br − concentration in a wide range of biological samples.

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