Radiation-related occupational cancer and its recognition criteria in South Korea

Ionizing radiation is a well-known carcinogen, and is listed as one carcinogenic agent of occupational cancer. Given the increase in the number of workers exposed to radiation, as well as the increase in concern regarding occupational cancer, the number of radiation-related occupational cancer claims is expected to increase. Unlike exposure assessment of other carcinogenic agents in the workplace, such as asbestos and benzene, radiation exposure is usually assessed on an individual basis with personal dosimeters, which makes it feasible to assess whether a worker's cancer occurrence is associated with their individual exposure. However, given the absence of a threshold dose for cancer initiation, it remains difficult to identify radiation exposure as the root cause of occupational cancer. Moreover, the association between cancer and radiation exposure in the workplace has not been clearly established due to a lack of scientific evidence. Therefore, criteria for the recognition of radiation-related occupational cancer should be carefully reviewed and updated with new scientific evidence and social consensus. The current criteria in Korea are valid in terms of eligible radiogenic cancer sites, adequate latent period, assessment of radiation exposure, and probability of causation. However, reducing uncertainty with respect to the determination of causation between exposure and cancer and developing more specific criteria that considers mixed exposure to radiation and other carcinogenic agents remains an important open question.

Comparison of work-related musculoskeletal symptoms between male cameramen and male office workers

BACKGROUND: Previous studies have classified cameramen’s job as physiologically heavy work and identified the risk factors of work-related musculoskeletal disorders (WRMDs) in cameramen. However, those studies limited their research subjects to cameramen. In this study, we compared the frequency and severity of WRMDs between cameramen and office workers. METHODS: A total of 293 subjects working in four broadcasting companies in Korea were recruited. A questionnaire survey was conducted for a month, starting in October 2016. The subjects were divided into cameramen and office workers according to their occupation. We compared the frequency and severity of WRMDs and ergonomic risk assessment results between the two groups. RESULTS: The high-risk WRMD group had a higher proportion of cameramen than office workers. Moreover, the high ergonomic risk group also had a higher proportion of cameramen than office workers for WRMDs in the upper extremities and waist+lower extremities. In the multivariable-adjusted model comparing cameramen and office workers, the odds ratio (OR) with 95% confidence interval (95% CI) for high-risk WRMDs was 3.50 (95% CI: 1.92–7.72) for the upper extremities and 3.18 (95% CI: 1.62–6.21) for the waist and the lower extremities. The ORs by body parts were 3.11 (95% CI: 1.28–7.57) for the neck, 3.90 (95% CI: 1.79–8.47) for the shoulders, and 4.23 (95% CI: 1.04–17.18) for the legs and feet. CONCLUSIONS: Our study suggests that cameramen are at high risk of WRMDs. Workplace improvements and management of the neck, shoulders, and lower extremities, which are susceptible to WRMDs, are necessary to prevent musculoskeletal disorders among cameramen.

Hazards and health problems in occupations dominated by aged workers in South Korea

BACKGROUND: South Korea's population is aging more rapidly than any other country. Aging of the productive population will lead to shortage of labor and the decreasing quality of the labor force in South Korea. South Korea needs health care strategies to support the establishment of work environments that are appropriate for elderly workers who have reduced physical capacity. This paper aims to identify occupations that are dominated by aged workers and assess the exposure to hazards and work-related health problems of aged workers in these occupations. METHODS: We identified the 20 occupations in South Korea that employ the most aged workers (at least 55 years-old), among all 149 occupations that are defined as minor categories (identified by three digits) by the Korean Standard Classification of Occupations (KSCO). Exposure to hazards and work-related health problems of individuals in these occupations were evaluated by analyzing the results of the fourth Working Conditions Survey of 2014. RESULTS: Among the 20 occupations that employ the most aged workers, ‘Elementary Occupations', which the KSCO classifies as major category (9), had the largest proportion of aged workers. After this, there were five occupations of skilled manual workers and six occupations of skilled non-manual workers. Aged workers in elementary and skilled manual occupations reported frequent exposure to job-specific hazards, such as noise, vibrations, high and low temperatures, solvents, and chemicals. Relative to other workers, aged workers in the occupations reported more frequent exposure to ergonomic hazards, such as tiring or painful positions, carrying or moving heavy loads, and repetitive movements, and also reported more work-related musculoskeletal disorders and general fatigue. Injury due to accident was common in machinery-handling occupations. CONCLUSION: Job-specific hazards should be reduced to prevent occupation-related disorders in elementary and skilled manual occupations that are dominated by aged workers.

Comparison of sleep quality based on direction of shift rotation in electronics workers

BACKGROUND: Previous studies have reported the effects of direction of shift rotation on sleep, however, the findings are inconsistent. In this study, we investigated sleep quality related to direction of shift rotation using large-scale data from shiftwork-specific health examinations of electronics workers. METHODS: This study included 4750 electronics workers working in a rotating 3-shift system who completed a medical examination for shift workers survey from January 1 to December 31, 2014, at a general hospital. The subjects were categorized into one of two groups according to direction of shift rotation. We compared sleep quality index between the subjects who worked in forward rotation and backward rotation systems. RESULTS: Backward rotation was positively associated with prevalence of poor sleep quality. In the multivariable-adjusted model, when comparing backward rotation to forward rotation, the odds ratio (OR) with 95 % confidence interval (95 % CI) for poor sleep quality was 1.95 (1.58–2.41). After stratifying by gender, the ORs (95 % CIs) for poor sleep quality in male and female was 1.92 (1.47–2.49) and 2.13 (1.47–3.08), respectively. In subgroup analyses, backward rotation was significantly associated with poor sleep quality in workers ≥30 years of age compared with workers <30 years of age (adjusted OR 2.60 vs. 1.89, respectively; P for interaction <0.001). CONCLUSIONS: Our study supports that a backward rotation system is associated with poor sleep quality. Forward rotation systems should be considered to reduce sleep problems.

Health care strategy for ensuring work ability in an aging Korea

The rapid aging trend in South Korea will cause a growing shortage of labor and decreasing quality of the labor force. The purpose of this commentary is to recommend a health care strategy to maintain and promote the work ability of employees in an aging Korea. Strategies to promote the work ability require the collaboration of governmental agencies at the central and local levels. First, the common goal should be the reinforcement of follow-up measure in general medical examinations and the promotion of healthy lifestyles for workers. Second, collaborating activities should be performed among the Worker’s Health Center, the Health Promotion Center, and community health centers. In conclusion, health care strategies for ensuring the work ability in an aging Korea require the collaboration of governmental agencies at the central and local levels.

Risk factors of work-related upper extremity musculoskeletal disorders in male cameramen

OBJECTIVE: The aim of this study is to determine the risk factors related to upper extremities work-related musculoskeletal disorders (WRMSDs) in cameramen. METHODS: A questionnaire survey was performed on 166 cameramen in a broadcasting station. The questionnaire consisted of questions on the general characteristics, the health behavior, work type and duration, physical burden, ergonomic posture, and musculoskeletal symptoms. Definition of musculoskeletal disorders was based on NIOSH criteria. RESULTS: The positive rate of WRMSDs symptoms by parts of the body was turned out to be the highest in the shoulder (14.5%) and the lowest in arm and elbow (6%). Logistic regression analysis revealed that symptoms in the shoulders increased with BMI (OR = 3.62, 95% CI = 1.03-12.71), physical burden (OR = 9.29, 95% CI = 1.72-61.78 in the very hard group) and ergonomic factors (OR = 4.50, 95% CI = 1.03-19.68). Ergonomic factors were only related to the symptoms of hand and wrist (OR = 10.21, 95% CI = 1.02-102.20). WRMSDs symptoms, in the whole upper extremities, were higher in the 50 or older age group (OR = 5.86, 95% CI = 1.03-33.26), higher BMI group (OR = 3.26, 95% CI = 1.28-13.53), non-exercise group (OR = 2.37, 95% CI = 1.24-12.59), high physical burden group (OR = 7.6, 95% CI = 1.34-52.74), and high grade ergonomic risk group (OR = 4.82, 95% CI = 1.29-16.06). CONCLUSION: The most serious musculoskeletal disorders of male cameramen were shoulder pain. Ergonomic factors and physical burden were the most significant factors affecting WRMSDs in cameramen in this study. Cameramen should be educated to be able to improve the ergonomic occupational environment and to set up preventive measures against the risk factors during work.

Healthcare workers infected with Middle East respiratory syndrome coronavirus and infection control

The outbreak of Middle East respiratory syndrome coronavirus(MERS-CoV) infection in South Korea has become a public health threat. There are many confirmed cases of MERS in healthcare workers. Understanding the nature of the infection and the mechanismof transmission will be a useful lesson. This paper gathers data from the press records in KCDC from May 20thto June 26th 2015to identify the age, sex, occupation and etiologic exposure of exposed healthcare workersin order to come up with a response plan. By June 26th, 2015, there were 181 confirmed cases of MERS-CoV infection in Korea. 36 (19.9%) of them were healthcare workers. These healthcare workers were exposed to MERS-CoV across 12 healthcare facilities, including Samsung Medical Center and Dae-Chung Hospital;threewere infected inside ambulances. Their occupational categories are as follows: 7 doctors (19.4%), 12 nurses (33.3%), 9 caregivers orgeriatric care assistants(25.0%), and 8 others (22.2%). These healthcare workers were infected by 12 super-spreaders. 30 of the workers(83.3%) were infected without being aware of their contact withMERS patients, while 6 (16.7%) were aware of this contact at the time of infection. The high number of confirmed cases of MERS-CoV inhealthcare workers is direct proof of the failure of crisis communication in South Korea, and the delay in the diagnosis of the index case was due to the lack of risk communication regardingthe threatof a MERS outbreak. Because the spread of MERS usually occursvia healthcare-associated transmission, infection control inhealthcare facilities must be strengthened.

Association of cadmium with diabetes in middle-aged residents of abandoned metal mines: the first health effect surveillance for residents in abandoned metal mines

OBJECTIVE: The aim of this study was to determine the association between urinary cadmium (U-cd) concentration and diabetes in middle-aged Korean residents of abandoned mines using the first Health Effect Surveillance for Residents in Abandoned Metal mines (HESRAM). METHODS: This study was cross-sectional study conducted on 719 residents between 40-70 years in 38 abandoned metal mines in Korea. Data was collected by HESRAM from 2008 to 2011. The correlation coefficient of U-cd and fasting blood glucose, odds ratio in urinary cadmium tertiles and diabetes prevalence was analyzed according to the sex category. RESULTS: The correlation coefficient U-cd concentration and fasting blood glucose was 0.182 in male. Logistic regression analysis in male revealed a third tertile odds ratio of U-cd (2 mug/g creatinine < U-cd) while diabetes prevalence was 1.81 (95 % CI 1.05-3.12) with adjusted age, BMI, smoking and alcohol consumption, region, family income. On the other hand, the odds ratio for third tertile of U-cd (3 mug/g creatinine < U-cd) between diabetes prevalence in female was 1.39 (95 % CI 0.52-3.72) in addition to adjusted menopausal status. CONCLUSIONS: Environmental exposure to cadmium in abandoned mine residents was associated with diabetes in male. Closed monitoring and periodic evaluation of the health effects of chronic environmental exposure on abandoned mines residents will be needed.

Relationship between Chronic Kidney Disease and Risk of Coronary Heart Disease in Korean Men

There have been many epidemiological researches of chronic kidney disease (CKD), accompanied by an increase in the incidence of coronary heart disease (CHD). However, as far as we know, little research has been done to examine the extent of the relationship between CKD and CHD as estimated by Framingham risk score (FRS) in Korean men. CKD was defined as either proteinuria or an eGFR of or = 20% (high). We defined FRS > or = 10% as more-than-a-moderate CHD risk group and FRS > or = 20% as a high CHD risk group, respectively. After adjusting for covariates, multivariable-adjusted logistic regression analyses showed a strong statistical significant relationship between CKD and high risk of CHD (adjusted OR, 1.95 [95% CI, 1.32-2.87]). Dipstick urinalysis and eGFR can be readily measured in most clinical settings. The measurement of kidney function may represent a relatively inexpensive and efficient way to identify individuals at higher risk for CHD.

Apolipoprotein B is Highly Associated with the Risk of Coronary Heart Disease as Estimated by the Framingham Risk Score in Healthy Korean Men

The aim of this study was to examine the association between serum apolipoprotein B (apoB) and the risk of coronary heart disease (CHD) using Framingham risk score (FRS) in healthy Korean men. A total of 13,523 men without medication history of diabetes and hypertension were enrolled in this study. The FRS is based on six coronary risk factors. FRS > or = 10% was defined as more-than-a-moderate risk group and FRS > or = 20% as high risk group, respectively. The logistic regression analyses were conducted. When quartile 1 (Q1) set as a reference, in unadjusted analyses, the Q2, Q3, Q4 of apoB level had increased odds ratio (OR) for the risk of CHD in both more-than-a-moderate risk and high risk group, respectively. After adjusting for confounding variables, multivariable-adjusted logistic regression analyses showed a strong relationship between the quartiles of apoB level and more-than-a-moderate risk and high risk group, respectively. These associations were attenuated, but still remained statistically significant. ApoB is found to be independently related to the risk of CHD using FRS in healthy Korean men, and the link between apoB and the risk of CHD is dose-depedent.

Worker's Compensation Claims and Approval Status for Occupational Cancers in Korea from 2000 to 2009 / 대한산업의학회지

OBJECTIVES: The purpose of this study is to analyze the characteristics of the occupational cancer claims compensated by the Industrial Accident Compensation Insurance that is operated by the Korea Workers' Compensation and Welfare Service (COMWEL). METHODS: Using the COMWEL electronic database, we collected 1,933 claims for occupational cancer based on the worker's compensation records in the COMWEL from 1 January 2000 to 31 December 2009. We analyzed the characteristics of the claims. RESULTS: The average number of claims per year for occupational cancer was 193 and the approval rate was 13.1% from 2000 to 2009. Men accounted for 93.7% of the approved cases and had a higher approval rate. Approval rates increased with age. Among claims for occupational cancer, the most common was digestive cancer. On the other hand, the highest approval rate was for mesothelioma claims, followed by respiratory cancer, lymphoid or hematopoietic cancer. By industry, claims were most common in manufacturing, but the approval rate was highest in mining and quarrying. By occupation, claims most commonly came from legislators, senior officials & managers, but the approval rate was highest for craft & related trades workers. The average of tenure period was 15.5 years for approved cases, but 10.3 years for non-approved cases, respectively. CONCLUSIONS: We analyzed the characteristics of the occupational cancer claims which were compensated for the last 10 years accrording to the approved results. For the purpose of long-term understanding and management of worker's compensation status for occupational cancer, we should gather accurate information of the carcinogenic factors involved in order to achieve the systematic improvement that is needed.

The Magnitude of Mortality from Ischemic Heart Disease Attributed to Occupational Factors in Korea: Attributable Fraction Estimation Using Meta-analysis

OBJECTIVES: Ischemic heart disease (IHD) is a major cause of death in Korea and known to result from several occupational factors. This study attempted to estimate the current magnitude of IHD mortality due to occupational factors in Korea. METHODS: After selecting occupational risk factors by literature investigation, we calculated attributable fractions (AFs) from relative risks and exposure data for each factor. Relative risks were estimated using meta-analysis based on published research. Exposure data were collected from the 2006 Survey of Korean Working Conditions. Finally, we estimated 2006 occupation-related IHD mortality. RESULTS: For the factors considered, we estimated the following relative risks: noise 1.06, environmental tobacco smoke 1.19 (men) and 1.22 (women), shift work 1.12, and low job control 1.15 (men) and 1.08 (women). Combined AFs of those factors in the IHD were estimated at 9.29% (0.3-18.51%) in men and 5.78% (-7.05-19.15%) in women. Based on these fractions, Korea's 2006 death toll from occupational IHD between the age of 15 and 69 was calculated at 353 in men (total 3,804) and 72 in women (total 1,246). CONCLUSION: We estimated occupational IHD mortality of Korea with updated data and more relevant evidence. Despite the efforts to obtain reliable estimates, there were many assumptions and limitations that must be overcome. Future research based on more precise design and reliable evidence is required for more accurate estimates.

Risk Factors of Work-related Upper Extremity Musculoskeletal Disorders in Male Shipyard Workers: Structural Equation Model Analysis

OBJECTIVES: This study was conducted to develop a model describing the interaction between lifestyle, job, and postural factors and parts of the upper extremities in shipyard workers. METHODS: A questionnaire survey was given to 2,140 workers at a shipyard in Ulsan City. The questionnaire consisted of questions regarding the subjects' general characteristics, lifestyle, tenure, physical burden, job control, posture and musculoskeletal symptoms. The overall relationship between variables was analyzed by a structural equation model (SEM). RESULTS: The positive rate of upper extremity musculoskeletal symptoms increased in employees who worked longer hours, had severe physical burden, and did not have any control over their job. Work with a more frequent unstable posture and for longer hours was also associated with an increased positive rate of musculoskeletal symptoms. Multiple logistic regression analysis showed that unstable posture and physical burden were closely related to the positive rate of musculoskeletal symptoms after controlling for age, smoking, drinking, exercise, tenure, and job control. In SEM analysis, work-related musculoskeletal disease was influenced directly and indirectly by physical and job stress factors, lifestyle, age, and tenure (p < 0.05). The strongest correlations were found between physical factors and work-related musculoskeletal disease. CONCLUSION: The model in this study provides a better approximation of the complexity of the actual relationship between risk factors and work-related musculoskeletal disorders. Among the variables evaluated in this study, physical factors (work posture) had the strongest association with musculoskeletal disorders.

Occupational Lung Cancer Surveillance in South Korea, 2006-2009

OBJECTIVES: The lung cancer mortality in Korea has increased remarkably during the last 20 years, and has been the first leading cause of cancer-related deaths since 2000. The aim of the current study was to examine the time trends of occupational lung cancer and carcinogens exposure during the period 2006-2009 in South Korea, by assessing the proportion of occupational burden. METHODS: We defined occupational lung cancer for surveillance, and developed a reporting protocol and reporting website for the surveillance of occupational lung cancer. The study patients were chosen from 9 participating university hospitals in the following 7 areas: Seoul, Incheon, Wonju, Daejeon, Daegu, Busan, and Gwangju. RESULTS: The combined proportion of definite and probable occupational lung cancer among all lung cancers investigated in this study was 10.0%, 8.6%, 10.7%, and 15.8% in the years 2006 to 2009, respectively, with an average of 11.7% over the four-year study period. The main carcinogens were asbestos, crystalline silica, radon, polyaromatic hydrocarbons (PAHs), diesel exhaust particles, chromium, and nickel. CONCLUSION: We estimated that about 11.7% of the incident lung cancer was preventable. This reveals the potential to considerably reduce lung cancer by intervention in occupational fields.

The Association Between Apolipoprotein E Genotype and Lipid Profiles in Healthy Woman Workers / 예방의학회지

OBJECTIVES: Plasma lipid profiles and Apolipoprotein E (ApoE) are established risk factors for cardiovascular disease (CVD). The knowledge of lipid profile may estimate the potential victims of cardiovascular disease before its initiation and progression and offers the opportunity for primary prevention. The most common ApoE polymorphism has been found to influence plasma lipid concentrations and its correlation with CVD has been extensively investigated in the last decade. METHODS: The ApoE polymorphism and its influence on plasma lipid were investigated in healthy woman workers. The information on confounding factors was obtained through a self-administered questionnaire and ApoE polymorphism was investigated using PCR. RESULTS: The relative frequencies of alleles E2, E3 and E4 for the study population (n=305) were 0.127, 0.750 and 0.121, respectively. ApoE polymorphism was associated with variations in plasma HDL-cholesterol lipid profile. In order to estimate the independent effects of alleles E2 and E4, as compared with E3, on lipid profile, multiple regression was performed after adjustment for confounding variables such as age, BMI, blood pressure, education status, insulin, fasting glucose, HOMA-IR, menopause. ApoE2 had a negative association with HDL cholesterol and ApoE4 had a positive association with LDL cholesterol. CONCLUSIONS: This study identified that the ApoE and CVD risk factors contribute to the lipid profiles, similar to other studies. The analysis including dietary intake and other gene in further studies may help to identify clear effects on lipid profiles as risk factor for CVD.

Influencing Factors in Approving Cerebrovascular and Cardiovascular Diseases as Occupational Disease in Seoul / 대한산업의학회지

OBJECTIVES: This study was performed to analyze the factors that affected the decision making process in approving workers' compensation claims for cerebrovascular and cardiovascular diseases cases that occurred just before refoming approval standards of Industrial Accident Compensation Insurance Act on 1 July 2008 and to provide fundamental information in preparing better standards. METHODS: We examined 283 claims cases involving cerebrovascular and cardiovascular diseases that occurred between 1 January, 2006 and 31 December, 2007 and collected data based on the worker's compensation records from 3 Seoul Regional Centers of the Workers' Compensation & Welfare Service. We analyzed the approval rates and odds ratios according to the general characteristics, injury information, past medical histories, and work related information using chi-square or univariate logistic regression. In addition, we identified the factors affecting the approval using multivariate logistic regression. RESULTS: Overall, 101 of the 283 cases were approved and approval rate was 35.7%. Approval rates differed significantly according to type of disease, survival, accident site, accident time, the presence of associated disease and overwork (p-value <0.05). In the multivariate logistic regression analysis with adjusted for age and sex, approval rate of death cases with associated disease was lower than cases without associated disease (OR 0.22, 95% CI 0.12~0.42). Approval rate of cases occurred in worksite was higher than others (OR 4.81, 95% CI 2.22~10.40). Cases of accepted overwork had a higher approval rate significantly than cases of not accepted (OR 28.53, 95% CI 9.74~83.52). CONCLUSION: Factors in approving cases of cerebrovascular and cardiovascular disease as cases involving occupational disease included conditions of overwork, high rate of accidents in the workplace and the presence of associated disease. It is necessary to investigate further behaviors of work and chronic work-related stress.

Compensation and Diagnosis of Asbestos Related Disease / 가정의학회지

Asbestos is a fibrous silicate that was widely used because of its heat resistance properties. Asbestos exposure affects workers involved in mining or processing asbestos or those involved in the use of asbestos in the shipbuilding, construction, and textile- and insulation-manufacturing industries. There are three commonly available types of asbestos; chrysotile (white asbestos), amosite (brown asbestos), and crocidolite (blue asbestos). All three have been associated with cancerous and non-cancerous lung disease. Asbestos-related diseases includes benign pleural effusion, pleural plaques, diffuse pleural thickening (a non-malignant disease affecting the lung lining), rounded atelectasis, asbestosis (a scarring of the lung tissue caused by asbestos), mesothelioma and lung cancer. Mesothelioma is a malignant pleural or peritoneal tumor that rarely occurs in patients who have not been exposed to asbestos. The latency period of most asbestos-related disease is 10 years or longer, asbestos-related disease remains an important public health issue. The clinical diagnosis of asbestos related diseases should be based on a detailed interview of the patient and occupational data on asbestos exposure, signs and symptoms, radiological and lung physiological findings and selected cytological, histological and other laboratory studies. Radiological imaging plays a pivotal role in the diagnosis and management of asbestos-related disease.

Cement Burn from Waterproof Work: A Case Study / 대한산업의학회지

BACKGROUND: Portland cement, which is a common material used in the construction industry, is known to cause caustic burns due to its alkalinity. Although cement burns are frequent and can be severe, many workers are inadequately aware of its risks. CASE: A 39-year-old man presented with exudative lesions and pain on his right hand after working with wet cement during waterproof work. The patient stated that wet cement entered his protective glove and he did not wash the cement off for 3 hours. Debridement of necrotic tissue and skin grafting was performed on his second and fifteenth hospital day respectively. CONCLUSION: The prevention of cement burns can be improved by extensive risk instruction and the provision of adequate skin protection.

Job Stress and Psychosocial Stress among Firefighters / 대한산업의학회지

OBJECTIVES: This study was performed to assess the level of job and psychosocial stresses in Korean firefighters, and to evaluate the determinants of psychosocial stress. METHODS: The study subjects comprised 1,712 male firefighters working in Seoul, Busan, and Kyungnam in 2006. We collected information about demographic and job-related characteristics, healthrelated behaviors, Korean Occupational Stress Scale (KOSS), and psychosocial Well-being Index (PWI) through self-administered questionnaires. Statistical analyses were done by using the chi-square-test and logistic regression model. RESULTS: The multiple logistic regression analyses indicated that the proportion of high-risk psychosocial stress is significantly higher in the groups with high job stress level in 'lack of rewards' (OR=2.90, 95% CI=2.18-3.85), 'occupational climate' (OR=1.92, 95% CI=1.47-2.51), 'job demand' (OR=1.72, 95% CI=1.32-2.23), 'job insecurity' (OR=1.53, 95% CI=1.17-2.01), 'interpersonal conflict' (OR=1.53, 95% CI=1.16-2.01), 'physical environment' (OR=1.45, 95% CI=1.11-1.89), and 'organizational injustice' (OR=1.38, 95% CI=1.04-1.85). CONCLUSIONS: Psychosocial stress might be adversely influenced by job stressors for the most part. Firefighters need job stress management to minimize their psychological problems.

The K121Q Polymorphism in ENPP1 (PC-1) Is Not Associated with Type 2 Diabetes or Obesity in Korean Male Workers

Type 2 diabetes is characterized by insulin resistance, and ENPP1 plays an important role in insulin resistance. We investigated the association of the ENPP1 K121Q polymorphism with both diabetes and obesity (body mass index [BMI]) in Korean male workers. The study design was case-control. Subjects were 1,945 male workers (type 2 diabetes, 195; non-diabetes, 1,750) of nuclear power plants who received examinations from March to October in 2004. We collected venous blood samples under fasting (> or =8 hr) conditions, calculated BMI by height and weight, and assessed relevant biochemical factors. The results of this study demonstrated that the ENPP1 121Q genotype (KQ+QQ types) was not associated with type 2 diabetes (odds ratios [OR], 0.854; 95% confidence interval [CI], 0.571-1.278) or obesity (OR, 0.933; 95% CI, 0.731-1.190). In addition, the frequency of the Q allele was not related to type 2 diabetes (OR, 0.911; 95% CI, 0.630-1.319) or obesity (OR, 0.962; 95% CI, 0.767-1.205). We concluded that the ENPP1 121Q allele is not a critical determinant for either diabetes or obesity in Korean males. The discordance between the results of this study and those derived from studies of Dominican, South Asian, Caucasian, Finnish, and French populations might be due to differences in genetic backgrounds between these populations.