Chronic Low-Level Cyanide Intoxication in an Electroplating Plant in Taiwan.

OBJECTIVE: This study aimed to investigate clinical symptoms among electroplating workers exposed to cyanide. METHODS: In this study, 26 silver-plating and 51 gold-plating workers completed questionnaires and were tested for urinary thiocyanates. Air cyanide, urinary thiocyanates, and clinical symptoms were compared between workers using Student t and χ 2 test and further analyzed by multivariate linear regression. RESULTS: Air cyanide and urinary thiocyanate were higher in the silver-plating plant than the gold-plating plant. In both plants, a dose-response relationship was observed between exposure status and thiocyanate levels. Silver-plating workers reported a higher frequency of almond odor detection, nasal bleeding, excessive salivation, skin scalding, and corrosion. Urinary thiocyanates were associated with the plant and exposure status, but not with smoking. CONCLUSIONS: Our study suggests that silver-plating workers had higher exposure and more symptoms. Urinary thiocyanate may be a useful biomarker for cyanide exposure.

Case reports of indium lung disease in Taiwan.

The production of indium-tin oxide has increased in the past decades due to the increased manufacture of liquid crystal displays (LCD). Taiwan is one of the highest indium-consuming countries worldwide. After repeated inhalation, indium oxide (In2O3) particles would accumulate in the lungs, resulting in severe lung effects. We report two workers of an LCD producing facility with elevated serum indium level up to 149 and 73.8 µg/L (normal value <3.5 µg/L), which was much higher than that observed in previous case reports in Taiwan. We collected their detailed working history, symptoms, pulmonary function, radiologic findings, and followed up for more than one year. We also performed workplace evaluation of the facility. We observed that sandblasters who clean components of ITO thin-film production machinery by sandblasting with aluminum oxide tend to have higher indium exposure with worse pulmonary functions and HRCT findings.

Characteristics of Decreased Pulmonary Function and Clinical Symptoms in Nickel Electroplating Workers.

OBJECTIVE: To investigate health problems, especially pulmonary function, among electroplating workers exposed to nickel. METHODS: We recruited 153 nickel-exposed and 74 control workers from electroplating shops in printed circuit board production plants. Questionnaires were conducted to collect basic information. Symptoms and pulmonary function were ascertained. RESULTS: The average urine nickel level of the 79 high-exposure, 74 low-exposure, and 74 control workers were 7.38 ±â€Š5.96, 5.79 ±â€Š4.75, and 5.27 ±â€Š3.89 µg/g Cr, respectively. Nickel-exposed workers had a significantly higher incidence of skin- and airway-based symptoms. A significant relationship between impaired pulmonary function and high (more than5.2 µg/g Cr) urine nickel level was observed. CONCLUSIONS: Nickel-exposed workers had significantly higher urine nickel levels with more skin-, airway-based symptoms, as well as impaired pulmonary function. A dose-response relationship between decreased pulmonary function and nickel exposure status was observed.

Nickel exposure and plasma levels of biomarkers for assessing oxidative stress in nickel electroplating workers.

CONTEXT: The mechanism of nickel-induced pathogenesis remains elusive. OBJECTIVE: To examine effects of nickel exposure on plasma oxidative and anti-oxidative biomarkers. MATERIALS AND METHODS: Biomarker data were collected from 154 workers with various levels of nickel exposure and from 73 controls. Correlations between nickel exposure and oxidative and anti-oxidative biomarkers were determined using linear regression models. RESULTS: Workers with a exposure to high nickel levels had significantly lower levels of anti-oxidants (glutathione and catalase) than those with a lower exposure to nickel; however, only glutathione showed an independent association after multivariable adjustment. DISCUSSION AND CONCLUSION: Exposure to high levels of nickel may reduce serum anti-oxidative capacity.

Do sanitary ceramic workers have a worse presentation of chest radiographs or pulmonary function tests than other ceramic workers?

BACKGROUND/PURPOSE: Silicosis remains the most prevalent occupational disease worldwide. There have been no specific studies focusing on the association between exposure settings at work and the clinical severity in silicosis patients. In this study, we describe and compare the clinical characteristics and silicosis-associated exposure history at work among workers from several types of ceramic production facilities in Taiwan. METHODS: We reviewed the medical records of 221 patients who were first diagnosed with silicosis at the Occupational Medicine Clinic of Northern Taiwan in 2012. For each patient, we collected data on demographic characteristics, smoking habits, working history, duration of exposure, and years on the first relevant job. We also retrieved clinical reports of the pulmonary function test and the baseline chest radiography used for silicosis staging. RESULTS: As compared to other ceramic workers, sanitary ceramic workers had a worse X-ray type (p=0.044), more advanced age (p<0.001), longer working duration (p=0.029), and a higher proportion of starting the first relevant job prior to the year 1975 (p=0.003). However, after adjusting for age, work duration, and an initial occupational exposure prior to 1975, sanitary ceramic workers showed a comparable risk for worse X-ray findings to other ceramic workers (adjusted odds ratio=1.18, p=0.704). Results of multivariable regression models on individual lung function parameter also suggested comparably impaired lung function tests between sanitary and other ceramic workers (p>0.05). CONCLUSION: In this study, we found that sanitary ceramic workers were at a similar risk to other ceramic workers for moderate to severe silicosis when older age and longer working duration were accounted for.

Blood oxidative stress in Taiwan workers exposed to carbon disulfide.

BACKGROUND: Overexposure to carbon disulfide (CS(2) ) has been associated with an increase in coronary heart disease, but the mechanisms mediating this effect remain unclear. We aimed to examine the relationship between CS(2) exposure and oxidative stress markers, in order to clarify the oxidative mechanisms involved in CS(2) -induced atherosclerosis. METHODS: A total of 89 workers from a viscose rayon plant were recruited for this study, and 111 workers not exposed to CS(2) served as controls. Cholesterol, triglyceride, malondialdehyde (MDA), superoxide dismutase (SOD), catalase, GSH peroxidase, as well as total antioxidants were analyzed. RESULTS: The workers exposed to CS(2) had significantly higher MDA levels and lower SOD levels than the controls. The average MDA levels were 776 ± 268.2 (240-1,220) in the high exposure (≥10 ppm; n = 38), 751.6 ± 274 (170-1,320) in the low exposure (<10 ppm; n = 51), and 550.4 ± 199 (115-1,050) mM in the control group (n = 111). The average SOD levels were 36.5 ± 38.8 (0-223.5), 39.3 ± 38.8 (0-160), and 58.8 ± 60.8 (5.25, 400) U/ml in the high exposure-, low exposure-, and control group, respectively. MDA level increased significantly at a cumulative CS(2) exposure of over 60 ppm-years. Dyslipoproteinemia was borderline significantly associated with CS(2) exposure and MDA level. CONCLUSIONS: These results indicate that CS(2) exposure can induce oxidative stress as well as reduce the levels of antioxidative enzymes, and that a cumulative exposure level of 60 ppm-years may be a threshold value for the oxidative and the antioxidant response. Am. J. Ind. Med. 54:637-645, 2011. © 2011 Wiley-Liss, Inc.

Inflammatory responses and oxidative stress from metal fume exposure in automobile welders.

OBJECTIVES: : Welding operations expose to metal fume. We investigated the inflammatory responses and oxidative stress from metal fume exposure in an automobile plant. METHODS: : We recruited 258 automobile workers and measured the urine zinc, copper, and nickel to determine the exposure level, and examined the white blood cells, and IL-6 as inflammatory responses to the metal fume exposure. We also examined the relationship between glutathione (GSH) and metals exposure. RESULTS: : There were significant association between urine metals levels and welding hours. Zinc was significantly associated with blood white cells, interleukin-6, and GSH. Copper was significantly associated with GSH, but nickel was significantly inversely associated with GSH. CONCLUSIONS: : Automobile welders appear to have significant metals exposure. White blood cells and IL-6 might be involved in inflammatory process of zinc fume exposure with zinc and copper increasing GSH, but nickel depleting it.

Pulmonary function abnormalities and airway irritation symptoms of metal fumes exposure on automobile spot welders.

BACKGROUND: Spot or resistance welding has been considered less hazardous than other types of welding. Automobile manufacturing is a major industry in Taiwan. Spot and arc welding are common processes in this industry. The respiratory effects on automobile spot welders exposed to metal fumes are investigated. METHODS: The cohort consisted of 41 male auto-body spot welders, 76 male arc welders, 71 male office workers, and 59 assemblers without welding exposure. Inductivity Coupled Plasma Mass Spectrophotometer (ICP-MS) was applied to detect metals' (zinc, copper, nickel) levels in the post-shift urine samples. Demographic data, work history, smoking status, and respiratory tract irritation symptoms were gathered by a standard self-administered questionnaire. Pulmonary function tests were also performed. RESULTS: There were significantly higher values for average urine metals' (zinc, copper, nickel) levels in spot welders and arc welders than in the non-welding controls. There were 4 out of 23 (17.4%) abnormal forced vital capacity (FVC) among the high-exposed spot welders, 2 out of 18 (11.1%) among the low-exposed spot welders, and 6 out of 130 (4.6%) non-welding-exposed workers. There was a significant linear trend between spot welding exposure and the prevalence of restrictive airway abnormalities (P = 0.036) after adjusting for other factors. There were 9 out of 23 (39.1%) abnormal peak expiratory flow rate (PEFR) among high-exposed spot welders, 5 out of 18 (27.8%) among the low-exposed spot welders, and 28 out of 130 (21.5%) non-welding-exposed workers. There was a borderline significant linear trend between spot welding exposure and the prevalence of obstructive lung function abnormalities (P = 0.084) after adjusting for other factors. There was also a significant dose-response relationship of airway irritation symptoms (cough, phlegm, chronic bronchitis) among the spot welders. Arc welders with high exposure status also had a significant risk of obstructive lung abnormalities (PEFR reduction). There was also a significant dose-response relationship of airway irritation symptoms (cough, phlegm, chest tightness, and chronic bronchitis) among the arc welders. CONCLUSIONS: These findings suggest that restrictive and obstructive lung abnormalities, and airway irritation symptoms are associated with spot and arc welding exposures.

Elevated triglyceride and decreased high density lipoprotein level in carbon disulfide workers in Taiwan.

Carbon disulfide (CS2) is a man-made product utilized primarily in the manufacture of viscose rayon. Overexposure to CS2 has been associated with an increase in coronary heart disease. The aims of this study were to examine the dose-response relationship of CS2 exposure and elevated lipid profile tests among CS2-exposed workers in Taiwan. A total of 132 workers were recruited from two viscose rayon plants. Air sampling was performed to determine the CS2 exposure of workers. Demographic data and work history were gathered by a standard self-administered questionnaire. Lipid profile tests were also performed by routine methods. The average CS2 exposure concentration was 50.6 +/- 25.6 ppm (range: 24-127 ppm) in the high-exposure group, 12.9 +/- 5 ppm (range: 5.2-22.3 ppm) in the mid-exposure group, and 3.5 +/- 1.2 ppm (range 0.97-5.2 ppm) in the low-exposure group. There were 21 out of 33 (63.7%) elevated triglyceride levels among high-CS2-exposure workers, 27 out of 64 (42.2%) among the middle-CS2-exposure, and 14 out of 35 (40%) among low-CS2-exposure workers, respectively. Compared to the low-CS2-exposure workers, the age- and weight-adjusted odds ratios (and 95% confidence intervals) of the prevalence of elevated triglyceride value were 1.12 (0.5, 2.7) for middle-CS2-exposure workers, and 2.81 (1.02, 7.8) for high-CS2-exposure workers. There was a significant linear trend between CS2 exposure and the prevalence of elevated triglyceride value (P = 0.046) after adjusting for other factors. There was also a lower prevalence of elevated HDL level in high-CS2-exposure workers than low-CS2-exposure workers (15.2% versus 31.4%). Compared to the low-CS2-exposure workers, the age- and weight-adjusted odds ratio (and 95% confidence intervals) of elevated HDL level were 0.34 (0.1, 1.18) for high-CS2-exposure workers, which was borderline significant. In conclusion, this study suggests that elevated triglyceride level and decreased HDL level are associated with CS2 exposure. The study also suggests that exposure to CS2 (concentration > 23.2 ppm, which was above the current TLV-TWA of 10 ppm) are significantly associated with increased risk and decreased protective effect for coronary heart disease.