The objective of this study is to investigate the differences in incidence rates of targeted diseases by classification of occupations among construction workers in Korea.

In a subject-based cohort of the Korean Construction Worker’s Cohort, we surveyed a total of 1,027 construction workers. As occupational exposure, the classification of occupations was developed using two axes: construction business and job type. To analyze disease incidence, we linked survey data with National Health Insurance Service data. Eleven target disease categories with high prevalence or estimated work-relatedness among construction workers were evaluated in our study. The average incidence rates were calculated as cases per 1,000 person-years (PY).

Injury, poisoning, and certain other consequences of external causes had the highest incidence rate of 344.08 per 1,000 PY, followed by disease of the musculoskeletal system and connective tissue for 208.64 and diseases of the skin and subcutaneous tissue for 197.87 in our cohort. We especially found that chronic obstructive pulmonary disease was more common in construction painters, civil engineering welders, and civil engineering frame mold carpenters, asthma in construction painters, landscape, and construction water proofers, interstitial lung diseases in construction water proofers.

This is the first study to systematically classify complex construction occupations in order to analyze occupational diseases in Korean construction workers. There were differences in disease incidences among construction workers based on the classification of occupations. It is necessary to develop customized occupational safety and health policies for high-risk occupations for each disease in the construction industry.

Indoor air pollution can cause and exacerbate asthma. We report a previously undescribed case of occupational asthma related to indoor air pollution in a worker at an indoor air gun shooting range and highlight the potential risk of developing occupational asthma in this environment.

A 31-year-old man presented with dyspnea, cough, and sputum and was diagnosed with asthma complicated by pneumonia. Objective evidence of asthma was obtained by performing a methacholine bronchial provocation test. It was suspected that the patient had occupational asthma, which began one month after changing jobs to work within the indoor air gun shooting range. The highest peak expiratory flow (PEF) diurnal variability on working days was 15%, but the highest variation was 24%, with 4 days out of 4 weeks having a variation of over 20% related to workplace exposure. Conversely, the diurnal variability on the rest days was 7%, and no day showed a variation exceeding 20%. The difference in the average PEF between working and rest days was 52 L/min. PEF deterioration during working days and improvement on rest days were noted.

The results obtained from the in-depth analysis of the PEF were adequate to diagnose the patient with occupational asthma. Exposure to indoor air pollution and lead and the patient’s atopy and allergic rhinitis may have contributed to the development of occupational asthma.

Job insecurity and emotional labor are poor job-related factors that are known to cause sleep disturbances in customer service workers. This study investigates the combined effect of emotional labor and job insecurity on sleep disturbance.

This study used data from the Fifth Korean Working Condition Survey and included 15,147 paid workers who serve customers below 65 years. We re-classified into 6 groups based on whether the degree of emotional labor increased (Rarely/Sometimes/Always) or whether job insecurity (No/Yes) was present. We performed propensity score matching for several covariates and calculated odds ratio (OR) and 95% confidence intervals (CIs) for sleep disturbance by logistic regression models using only matched subjects.

Workers exposed to emotional labor and job insecurity had significantly higher risk for 3 dimensions of sleep disturbance (difficulty falling asleep, waking up repeatedly during the sleep, and waking up with feeling of fatigue) (OR [95% CI]: 1.44 [1.22–1.69], 1.18 [0.99–1.40], 1.52 [1.30–1.79] for emotional labor; and 2.00 [1.75–2.29], 2.20 [1.91–2.53], 1.67 [1.45–1.92] for job insecurity). Compared to those who were exposed to both emotional labor rarely and without job insecurity, when workers had both poor job factors, the OR (95% CI) for sleep disturbance for difficulty falling asleep, waking up repeatedly during the sleep, and waking up with feeling of fatigue were 3.05 (2.42–3.86), 2.89 (2.26–3.69), and 2.60 (2.06–3.29), respectively. The relative excess risk due to Interaction of job insecurity and emotional labor was significant only for difficulty falling asleep, but not the other 2 sleep disturbance dimensions.

Customer service workers suffered from severe sleep disturbances according to the existing degree of emotional labor and job insecurity. The combined effect of both could have an additive influence on serious sleep disturbance among customer service workers.

Dependent self-employment is precarious employment, which can be vulnerable to mental health problems. This study aimed to investigate the association of dependent self-employment with depression, anxiety, and sleep disorder in South Korea.

This study used data from the Fourth Korean Working Conditions Survey and included 32,691 paid workers. Dependent self-employment and self-reported depression/anxiety, and sleep disorder were investigated using a questionnaire. Logistic regression analysis was performed to investigate the association between dependent self-employment and mental health problems.

Of the 32,691 paid workers, 2,371 (7.3%) were dependent self-employed workers. The odds ratio (OR) of dependent self-employment for self-reported depression/anxiety was 1.78 (95% confidence interval [CI]: 1.29–2.45) and the OR of dependent self-employment for self-reported sleep disorder was 1.26 (95% CI: 1.01–1.59) compared to other paid workers.

Dependent self-employment is related to an increased risk of self-reported depression/anxiety and sleep disorder in South Korea.