Acute respiratory symptoms and evacuation-related behavior after exposure to chlorine gas leakage

BACKGROUND: A study was performed on the accidental chlorine gas leakage that occurred in a factory of printed circuit boards manufactured without chlorine. Health examination was performed for all 52 workers suspected of exposure to chlorine gas, and their evacuation-related behaviors were observed in addition to analyzing the factors that affected the duration of their acute respiratory symptoms. METHODS: Behavioral characteristics during the incidence of the accidental chlorine gas leakage, the estimated time of exposure, and the duration of subjective acute respiratory symptoms were investigated. In addition, clinical examination, chest radiography, and dental erosion test were performed. As variables that affected the duration of respiratory symptoms, dose group, body weight, age, sex, smoking, work period, and wearing a protective gear were included and analyzed by using the Cox proportional hazard model. RESULTS: Of 47 workers exposed to chlorine gas, 36 (77 %) developed more than one subjective symptom. The duration of the subjective symptoms according to exposure level significantly differed, with a median of 1 day (range, 0–5 days) in the low-exposure group and 2 days (range, 0–25 days) in the high-exposure group. Among the variables that affected the duration of the acute respiratory symptoms, which were analyzed by using the Cox proportional hazard model, only exposure level was significant (hazard ratio 2.087, 95 % CI = 1.119, 3.890). Regarding the evacuation-related behaviors, 22 workers (47 %) voluntarily evacuated to a safety zone immediately after recognizing the accidental exposure, but 25 workers (43 %) delayed evacuation until the start of mandatory evacuation (min 5, max 25 min). CONCLUSIONS: The duration of the subjective acute respiratory symptoms significantly differed between the low- and high-exposure groups. Among the 27 workers in the high-exposure group, 17 misjudged the toxicity after being aware of the gas leakage, which is a relatively high number.

Overlap syndrome with Sjögren’s syndrome and systemic sclerosis in a steel rolling mill worker: a case report

BACKGROUND: There are few reports about work-related factors associated with Sjögren’s syndrome. We report a case of overlap syndrome with Sjögren’s syndrome and systemic sclerosis. CASE PRESENTATION: A 54-year-old man was admitted due to dyspnea on exertion. The results of physical examination and laboratory findings were compatible with Sjögren’s syndrome with systemic sclerosis. The patient had no pre-existing autoimmune disease, and denied family history of autoimmune disease. The patient worked in the large-scale rolling department of a steel manufacturing company for 25 years. Hot rolling is a rolling process performed at between 1100 °C and 1200 °C, generating a high temperature and a large amount of fumes, involving jet-spraying of water throughout the process to remove the instantaneously generated oxide film and prevent the high generation of fumes. In this process, workers could be exposed to silica produced by thermal oxidation. Other potential toxic substances including nickel and manganese seemed to be less likely associated with the patient’s clinical manifestations. CONCLUSIONS: Occupational exposure to silica seemed to be associated with the patient’s clinical manifestations of overlap syndrome with Sjögren’s syndrome and systemic sclerosis. Although the underlying mechanism is still unclear, autoimmune disease including Sjögren’s syndrome affects women more often than men and there was no family history of autoimmune disease. These suggested that there was an association between occupational silica exposure and the disease of the patient. Future research about the association between long-term low dose exposure to silica and the development of autoimmune diseases should be encouraged.

The Relevance of Hyperuricemia and Metabolic Syndrome and the Effect of Blood Lead Level on Uric Acid Concentration in Steelmaking Workers

OBJECTIVES: Uric acid concentration is known to increase the prevalence of metabolic syndrome by affecting its components, resulting in increased risk of cerebrovascular and cardiovascular diseases, and long-term lead exposure is known to affect this serum uric acid level. In this study, we aimed to examine the association between the causes of hyperuricemia and metabolic syndrome, and to determine whether an increased blood lead level affects hyperuricemia. METHOD: Anthropometric measurements, surveys, and blood tests were conducted between May and June 2012 in 759 men working in the steelmaking process at a domestic steel company. Workers were divided into 2 groups according to the presence or absence of hyperuricemia, and an analysis was performed to examine its association with metabolic syndrome. In addition, the workers were divided into 3 groups according to the blood lead level to analyze the association between blood lead and hyperuricemia. RESULTS: The geometric mean (standard deviation) of the blood lead levels in the hyperuricemia group was significantly higher than that of the healthy group (3.8 [1.8] vs. 3.3 [1.8] microg/dL). The adjusted odds ratio for metabolic syndrome of the hyperuricemia group increased significantly to 1.787 (1.125-2.839) compared with the healthy group. In addition, the adjusted odds ratios for the occurrence of hyperuricemia in the tertile 2 (2.61-4.50 microg/dL) and tertile 3 groups (>4.50 microg/dL) according to blood lead level significantly increased to 1.763 (1.116-2.784) and 1.982 (1.254-3.132), respectively, compared with the tertile 1 group (< 2.61 microg/dL). CONCLUSION: Hyperuricemia is believed to function as an independent risk factor for metabolic syndrome, while lead seems to increase the serum uric acid level even at a considerably low blood level. Therefore, attention should be given to patients with hyperuricemia and metabolic syndrome who are prone to lead exposure, and a prospective study should be conducted to identify their causal relationship.

Risk Assessment for Cardiovascular Diseases in Male Workers: Comparing KOSHA Guidelines and the Framingham Risk Score System / 대한산업의학회지

OBJECTIVES: This study aimed to investigate the 10-year risk of cardiovascular disease (CVD) by Framingham risk score (FRS) who classified as "healthy group" by Korean Occupational Safety and Health Agent (KOSHA)' s cardiovascular risk assessment. METHODS: The subjects of this study were 1,781 male workers in a large steel company. Health status was obtained periodically through medical examinations and questionnaires. We assessed cardiovascular risk using KOSHA guidelines and calculated the 10-year risk of cardiovascular disease using the Framingham risk score for those categorized to the "healthy group" by KOSHA guideline. A closer examination of cardiovascular risk factors was performed in 62 subjects paradoxically placed in the "healthy group" by KOSHA guidelines and the "high-risk group" by FRS. RESULTS: Among the "healthy group" by KOSHA's cardiovascular risk assessment, 230(15.8%) subjects had more than 3 CVD risk factors and 62(4.2%) subjects were high risk group (more than 20%) in 10-years risk of CVD by Framingham risk score. Modifiable risk factors included cigarette smoking (96.8%), high serum total cholesterol (82.3%), high serum triglyceride (66.1%), insufficient physical activity (66.1%), and obesity (58.1%). CONCLUSIONS: Among subjects with normal blood pressure, it seems that KOSHA guidelines underestimate CVD risk, identified by the Framingham risk score. For the effective prevention and management of CVD, modifiable risk factors, such as cigarette smoking, dyslipidemia, and obesity, need to be constructively controlled.