A comprehensive study of deaths due to exposure to humidifier disinfectant in Korea: focusing on medical records, assessment of exposure to humidifier disinfectants, and causes of death.

OBJECTIVES: We aimed to determine the characteristics of the deceased victims of deaths caused by exposure to humidifier disinfectants, and present the distribution of the victims' data submitted for damage application, demographic characteristics, imaging findings, characteristics of humidifier disinfectant exposure, and distribution of the causes of death. METHODS: An integrated database of victims was established using the medical records data of 1,413 victims submitted during the application for death damage caused by exposure to humidifier disinfectants, and the demographic characteristics, medical records, imaging findings, exposure characteristics, and cause of death were examined. RESULTS: The average numbers of data submissions of each applicant for death damage were 3.0 medical use records. A total of 608 (43.0%) victims had more than one finding of acute, subacute, or chronic interstitial lung diseases. The average daily and cumulative use times of the victims were 14.40 and 24,645.81 hours, respectively, indicating greater exposure in this group than in the survivors. The humidifier disinfectants' components comprised polyhexamethylene guanidine (72.8%), chloromethylisothiazolinone/methylisothiazolinone (10.5%), other components (15.0%), and oligo-[2-(2-ethoxy)-ethoxyethyl] guanidine chloride (1.5%). The components' distribution was 67.8% for single-component use, which was higher than that in the survivors (59.8%). The distribution of the causes of death were: respiratory diseases (54.4%), neoplasms (16.8%), and circulatory diseases (6.3%). Other interstitial lung diseases (65.5%) were the most common cause of death among those who died due to respiratory diseases. CONCLUSIONS: Careful discussions of appropriate remedies should be conducted based on a comprehensive understanding of the characteristics of the deceased victims, considering their specificities and limitations.

Association between nicotine dependency with occupational injury in Korean men.

BACKGROUND: The relationship between smoking status or second-hand smoking and occupational injuries has been the subject of considerable study, but few have studied the relationship between nicotine dependence and occupational injuries. The objective of this study was to investigate the relationship between nicotine dependence and occupational injury among employees at a range of Korean companies. METHODS: Initially, the personal and occupational characteristics and nicotine dependences of workers were measured, and 12 months later a survey was used to determine whether subjects had experienced any occupational injury. This study was conducted in several workplaces on 6,893 male workers in manufacturing and service industries that received health screening at Inha University Hospital in Incheon. RESULTS: The adjusted odds ratios (ORs) of occupational injury in the low, moderate, and high nicotine dependence groups were 1.38 (95% confidence interval [CI]: 1.04-1.84), 1.52 (95% CI: 1.10-2.10), and 1.71 (95% CI: 0.92-3.19), respectively. For smokers only, adjusted ORs tended to increase linearly (p for trend < 0.05). When only smokers were included, analysis of continuous FTND (Fagerstrom Test of Nicotine Dependence) scores showed that adjusted OR increased by 1.10 (95% CI: 1.03-1.19) per FTND point. After stratifying the data by working type and working hours per week, the non-shift work group maintained this relationship (OR: 1.13, 95% CI: 1.04-1.24) and OR was higher in the group that works more than 60 hours per week with FTND score as a continuous variable (OR: 1.24, 95% CI: 1.07-1.44). CONCLUSIONS: The study shows nicotine dependency might affect occupational injury. From a short-term perspective, addressing worker's nicotine dependence by giving an adequate break time or smoking area might reduce work-related injuries.

Relationship between fatigue severity scale and occupational injury in Korean workers.

BACKGROUND: The aim of this study is to investigate the relationship between fatigue and occupational injury. METHODS: This study was conducted at a university hospital in 2014 and 2015. In 2014, the fatigue severity scale (FSS) was used to evaluate workers' fatigue levels. Later, when the same workers were examined in 2015, a questionnaire survey was conducted to determine whether they had experienced absences or treatment for work-related accidents. The χ2 test was used to analyse the relationship between demographic characteristics, fatigue levels, and occupational injuries. After controlling for confounders, a logistic regression analysis was performed to calculate the odds ratios (ORs). RESULTS: In 2014, 19,218 workers were screened during health examination and their fatigue level were evaluated using FSS questionnaires. in 2015, workers' occupational injury was evaluated. In result, men in the moderate- and high-fatigue groups, after adjusting for age, smoking and drinking habits, chronic diseases, and occupational factors such as size of company industrial classification and type of work (shift or non-shift), adjusted ORs for hospital treatment due to occupational injury were 1.76 (95% confidence interval [CI]: 1.39-2.24) and 2.61 (95% CI:1.68-4.06), respectively. Among men in the medium- and high-fatigue groups, the adjusted ORs for absence due to occupational injury were 2.06 (95% CI: 1.52-2.80) and 3.65 (95% CI: 2.20-6.05), respectively. No significant association was observed between fatigue and occupational injury in women. CONCLUSIONS: Male workers with high fatigue levels have a higher risk of experiencing work injuries. This study suggests that active intervention be considered to prevent injuries in workers with high scores on workplace fatigue evaluation scales.

Comparison of Long Term Follow-up Chest CT Imaging in Adult and Pediatric Patients with Humidifier Disinfectant-related Lung Injury.

BACKGROUND: To compare the chest computed tomography (CT) images of children and adults in families with clusters of humidifier disinfectant-related lung injury (HDLI) after cessation of exposure to humidifier disinfectant (HD). METHODS: We reviewed medical records of 19 families with 43 patients (21 adults, 22 children) among families, which had at least one adult and one child with HDLI. Each family was exposed to the same HD exposure environment. RESULTS: In adults, centrilobular nodules were predominant (95.2%) in chronic HDLI findings after cessation of exposure to HD, however, in children, normal pattern was most prevalent on chest CT (45.5%), followed by centrilobular nodule (36.4%), bizarre lung cysts (36.4%), and reticulation (13.6%). CONCLUSION: Unlike the known chronic HDLI finding of adults, centrilobular nodules were only present in 36.4% of children. The frequency of bizarre lung cysts were significantly greater in children than that in adults after cessation of similar exposure to HD. Thus, bizarre lung cysts may be useful as another novel finding of chronic HDLI in children who have no history of pulmonary infection or other perinatal disorder such as hyaline membrane disease or other interstitial lung disease.

Characteristics of a new respiratory syndrome associated with the use of a humidifier disinfectant: humidifier disinfectant-related respiratory syndrome (HDRS).

OBJECTIVES: The purpose of this study was to characterize a new respiratory syndrome associated with exposure to a humidifier disinfectant (HD) in South Korea that is distinct from the well-known HD-related lung injury (HDLI). The authors identified this condition in 24 study subjects who were family members of patients with definite or probable HDLI (referred to as index cases), and were exposed to HD in the same room as the index cases. MATERIAL AND METHODS: The authors reviewed medical records of 236 family members in 110 families who were exposed to HD in the same rooms and residences as the index cases. RESULTS: They identified 24 family members who were exposed to HD in the same rooms and residences as the index cases, and who developed respiratory disorders that were distinct from HDLI. The clinical signs and symptoms of these individuals were in the upper respiratory tract, such as allergic rhinitis and croup, or in the lower respiratory tract, such as bronchitis and pneumonia. The diffusing capacity of the lung fordetermicarbon monoxide was reduced in 9 of 12 children (data not available for 1 child), and in 4 of 5 adults (data not available for 6 adults). The percent forced vital capacity and forced expiratory volume in one second/forced vital capacity ratios were within the normal ranges in most patients. The computed tomography findings, which mostly indicated non-specific inflammation, were inconsistent with the radiological diagnostic criteria for HDLI, but were abnormal in 8 of 11 adults, and in 2 of 13 children. CONCLUSIONS: The authors propose a new condition, i.e., HD-related respiratory syndrome (HDRS), which is characterized by mild to moderate or atypical respiratory symptoms and signs, and is related to HD exposure, but is distinct from HDLI. The recognition of HDRS may provide a basis for understanding the natural history of HD-related respiratory problems, and for capturing the whole spectrum of HD-related clinical manifestations in the respiratory tract. Int J Occup Med Environ Health. 2020;33(6):829-39.

Relationship between occupational sunlight exposure and the incidence of renal cancer.

BACKGROUND: The risk factors for renal cancer include smoking, obesity, hypertension, and exposure to trichloroethylene. Recent studies have shown that low sunlight exposure increases the risk of developing a range of cancers, including renal cancer. Given that most of the daytime is spent at work, a lack of occupational sunlight exposure can be a risk factor for renal cancer. Therefore, this study examined the relationship between occupational sunlight exposure and the incidence of renal cancer. METHODS: This was a university hospital-based case-control study on renal cancer. Of the 706 newly diagnosed patients with renal cell carcinoma (RCC), 633 cases were selected; 73 who had no occupational history were excluded. In addition, 633 controls were selected from the general population after 1:1 matching with respect to sex, age (within 5 years), and residential area (constituency-level). Information on sunlight exposure by the occupational group was referred to data from France. To estimate the association between occupational sunlight exposure and the RCC risk, the odds ratios (ORs) were calculated using conditional logistic regression analysis. RESULTS: Sunlight exposure was divided into quartiles and the risk of RCC was analyzed. The adjusted OR of RCC (OR: 0.664, 95% confidence interval: 0.449-0.983) was significantly lower for the Q4 group than Q1 group but the Q2 and Q3 groups did not show significant results. The risk of RCC tended to decrease with increasing exposure to sunlight (p for trend < 0.028). CONCLUSIONS: Higher occupational sunlight exposure reduces the risk of RCC.

Trends in the Prevalences of Selected Birth Defects in Korea (2008⁻2014).

Little information is available on the prevalences of birth defects in Korea. The aims of this study were to estimate recent prevalences of selected birth defects and to analyze the prevalence trends of these defects during the period from 2008 to 2014. Prevalences were calculated for 69 major birth defects using health insurance claim data obtained from the Korea National Health Insurance Service (NHIS). Prevalence rate ratios were calculated using Poisson regression to analyze trends over the 7-year study period. The overall prevalence of a major birth defect was 446.3 per 10,000 births (95% CI: 444.0⁻448.6); 470.9 per 10,000 births (95% CI: 467.6⁻474.2) for males and 420.2 per 10,000 births (95% CI: 417⁻423.4) for females. The prevalence rates of the most common birth defects over the study period were; septal defect (138.2 per 10,000; 95% CI: 136.9⁻139.5), congenital hip dislocation (652 per 10,000; 95% CI: 64.1⁻65.9), and ventricular septal defect (62.62 per 10,000; 95% CI: 61.7⁻63.5). During the study period, a significant increase in the prevalence of a major birth defect was observed with a prevalence rate ratio (PRR) of 1.091. The strongest trend was observed for renal dysplasia, which had a PRR of 1.275 (95% CI: 1.211⁻1.343), and upward trends were observed for urogenital anomalies, such as, renal agenesis (PRR 1.102, 95% CI: 1.067⁻1.138), undescended testis (PRR 1.082, 95% CI: 1.072⁻1.093) and hypospadias (PRR 1.067, 95% CI: 1.044⁻1.090). This study shows an overall increase in the prevalences of birth defects, including hypospadias and undescended testis, which are known to be associated with endocrine factors. In the future, standardized birth defect registries should be established to enable these trends to be monitored.

Lung Cancer Risk and Residential Exposure to Air Pollution: A Korean Population-Based Case-Control Study.

PURPOSE: To investigate the association between long-term exposure to ambient air pollution and lung cancer incidence in Koreans. MATERIALS AND METHODS: This was a population-based case-control study covering 908 lung cancer patients and 908 controls selected from a random sample of people within each Korean province and matched according to age, sex, and smoking status. We developed land-use regression models to estimate annual residential exposure to particulate matter (PM10) and nitrogen dioxide (NO2) over a 20-year exposure period. Logistic regression was used to estimate odds ratios (ORs) and their corresponding 95% confidence intervals (CI). RESULTS: Increases in lung cancer incidence (expressed as adjusted OR) were 1.09 (95% CI: 0.96-1.23) with a ten-unit increase in PM10 (µg/m³) and 1.10 (95% CI: 1.00-1.22) with a ten-unit increase in NO2 (ppb). Tendencies for stronger associations between air pollution and lung cancer incidence were noted among never smokers, among those with low fruit consumption, and among those with a higher education level. Air pollution was more strongly associated with squamous cell and small cell carcinomas than with adenocarcinoma of the lung. CONCLUSION: This study provides evidence that PM10 and NO2 contribute to lung cancer incidence in Korea.

Impact of prenatal exposure to polycyclic aromatic hydrocarbons from maternal diet on birth outcomes: a birth cohort study in Korea.

OBJECTIVE: Polycyclic aromatic hydrocarbons (PAH) are common dietary exposures that cross the human placenta and are classified as a probable human carcinogen. The aim of the present study was to investigate the potential impact of exposure to PAH-containing meat consumed during pregnancy on birth outcomes. DESIGN: Prospective birth cohort study. Only non-smoking women with singleton pregnancies, who were free from chronic disease such as diabetes and hypertension, were included in the study. Maternal consumption of PAH-rich meat was estimated through FFQ. Multiple linear regression was used to assess factors related to higher intake and the association between dietary PAH and birth outcomes. SETTING: Republic of Korea, 2006-2011. SUBJECTS: Pregnant women (n 778) at 12-28 weeks of gestation enrolled in the Mothers and Children's Environmental Health (MOCEH) study. RESULTS: The multivariable regression model showed a significant reduction in birth weight associated with higher consumption level of foods rich in PAH, such as grilled or roasted meat, during pregnancy (ß=-17·48 g, P<0·05 for every 1 point higher in meat score). Further adjusting for biomarkers of airborne PAH did not alter this association. There was no evidence that higher consumption level of PAH-rich meat shortens the duration of gestation (P=0·561). Regression models performed for birth length and head circumference produced negative effects that were not statistically significant. CONCLUSIONS: Consumption of higher levels of barbecued, fried, roasted and smoked meats during pregnancy was associated with reduced birth weight. Dietary risk of PAH exposure in Korean women is of concern.

Combined approaches using adverse outcome pathways and big data to find potential diseases associated with humidifier disinfectant.

According to previous survey, about two million of people were expected to suffer from toxic effects due to humidifier disinfectant (HD), regardless of healing or not. Extremely small group are recognized as HDs' victims. Up to now, previous research tried to focus on interstitial fibrosis on terminal bronchiole because it is specific finding, compared with other diseases. To figure out overall effects from HDs, we recommend adverse outcome pathways (AOPs) as new approach. Reactive oxygen species (ROS) generation, decreased T-cell and pro-inflammatory cytokine release from macrophage could be key events between the exposure to HDs and diseases. ROS generation, decreased cell and pro-inflammatory cytokine release from macrophage could be cause of interstitial fibrosis, pneumonia and many other diseases such as asthma, allergic rhinitis, allergic dermatitis, fetal death, premature baby, autoimmune disease, hepatic toxicity, renal toxicity, cancer, and so on. We predict potential disease candidate by AOPs. We can validate the real risk of the adverse outcome by epidemiologic and toxicologic study using big data such as National Health Insurance data and AOPs knowledge base. Application of these kinds of new methods can find the potential disease list from the exposure to HD.

Nationwide Study of Humidifier Disinfectant Lung Injury in South Korea, 1994-2011. Incidence and Dose-Response Relationships.

RATIONALE: Humidifier disinfectant lung injury is an acute lung disease attributed to recurrent inhalation of certain disinfectant aerosols emitted from room humidifiers. An outbreak of this toxic lung injury occurred in South Korea from 1995 until all humidifier disinfectant products were recalled from the consumer market by the government in 2011. OBJECTIVES: A nationwide study was conducted to ascertain and classify all potential cases of humidifier disinfectant lung injury in Korea and to assess dose-response relationships. METHODS: By several mechanisms, clinicians and the general public were invited to report all suspected cases of humidifier disinfectant lung injury to public health officials in South Korea. A committee was convened to define diagnostic criteria based on pathologic, radiologic, and clinical findings for index cases, combined with assessment of environmental exposure to humidifier disinfectants. Clinical review and environmental assessments were performed and later combined to determine overall likelihood of disease for each study participant, classified as definite, probable, possible, or unlikely. Survival time from exposure to onset of symptoms was analyzed to assess dose-response relationships. Three broad categories of risk factors were examined: (1) biological susceptibility, (2) temporal cycle of exposure and recovery, and (3) spatial conditions and density of disinfectant. MEASUREMENTS AND MAIN RESULTS: Of 374 possible cases identified and reviewed, 329 were unanimously classified by the diagnostic committee, as follows: 117 definite, 34 probable, 38 possible and 140 unlikely cases. A total of 62 individuals with definite or probable disease died. Risk factors examined for polyhexamethyleneguanidine phosphate exposure that were found to be significant in shortening survival included age 4 years or younger at onset, use of disinfectant for 7 days per week, airborne density of 800 µg/m(3) or more of disinfectant, and daily exposure 11 or more hours in duration. CONCLUSIONS: Dose-response analysis indicated that development of humidifier disinfectant lung injury and death were associated strongly with recurrent, intense, acute exposure without sufficient recovery time between exposures, more so than long-term cumulative exposure. These findings may explain some reversible or clinically unapparent cases among coexposed family members.

Relationship between Exposure to Household Humidifier Disinfectants and Risk of Lung Injury: A Family-Based Study.

BACKGROUND: In South Korea, a cluster of acute lung disease patients included lung injury disease suspected of being caused by the use of humidifier disinfectants. We examined the relationship between humidifier disinfectant exposure and clinically diagnosed humidifier disinfectant-associated lung injury (HDLI) in a family-based study. METHODS: This case-control study included 169 clinically confirmed HDLI cases and 303 family controls who lived with the HDLI patients. A range of information on exposure to humidifier disinfectants was obtained using a structured questionnaire and field investigations. Odds ratios (ORs) and confidence intervals (CIs) were estimated using unconditional logistic regression models that were adjusted for age, sex, presence of a factory within 1 km of residence, and the number of household chemical products used. RESULTS: HDLI risk increased approximately two-fold or more among the highest quartile compared with the lowest quartile in terms of the hours sleeping in a room with an operating humidifier treated with disinfectant (adjusted OR = 2.0, 95 % CI = 1.1-3.7), average hours of disinfectant-treated humidifier use per day (adjusted OR = 2.1, 95 % CI = 1.0-4.5), airborne disinfectant intensity (adjusted OR = 2.6, 95% CI = 1.2-5.3), and cumulative disinfectant inhalation level (adjusted OR = 2.0, 95% CI = 1.0-4.1). HDLI risk increased as the distance of the bed from humidifier gets shorter; compared with longer distance (> 1 m), the odds ratio was 2.7 for 0.5 to 1 m (95 % CI = 1.5-5.1) and 13.2 for <0.5 m (95 % CI = 2.4-73.0). CONCLUSIONS: The use of household humidifier disinfectants was associated with HDLI risk in a dose-response manner.

A meta-analysis of exposure to particulate matter and adverse birth outcomes.

OBJECTIVES: The objective of this study was to conduct a systematic review to provide summarized evidence on the association between maternal exposure to particulate air pollution and birth weight (BW) and preterm birth (PTB) after taking into consideration the potential confounding effect of maternal smoking. METHODS: We systematically searched all published cohort and case-control studies examining BW and PTB association with particulate matter (PM, less than or equal to 2.5µm and 10.0 µm in diameter, PM2.5 and PM10, respectively) from PubMed and Web of Science, from January 1980 to April 2015. We extracted coefficients for continuous BW and odds ratio (OR) for PTB from each individual study, and meta-analysis was used to combine the coefficient and OR of individual studies. The methodological quality of individual study was assessed using a standard protocol proposed by Downs and Black. Forty-four studies met the inclusion criteria. RESULTS: In random effects meta-analyses, BW as a continuous outcome was negativelyassociated with 10 µg/m(3) increase in PM10 (-10.31 g; 95% confidence interval [CI], -13.57 to -3.13 g; I-squared=0%, p=0.947) and PM2.5 (-22.17 g; 95% CI, -37.93 to -6.41 g; I-squared=92.3%, p <0.001) exposure during entire pregnancy, adjusted for maternal smoking. A significantly increased risk of PTB per 10 µg/m(3) increase in PM10 (OR, 1.23; 95% CI, 1.04 to 1.41; I-squared=0%, p =0.977) and PM2.5 (OR, 1.14; 95% CI, 1.06 to 1.22; I-squared=92.5%, p <0.001) exposure during entire pregnancy was observed. Effect size of change in BW per 10 µg/m(3) increase in PM tended to report stronger associations after adjustment for maternal smoking. CONCLUSIONS: While this systematic review supports an adverse impact of maternal exposure to particulate air pollution on birth outcomes, variation in effects by exposure period and sources of heterogeneity between studies should be further explored.

Increase of diesel car raises health risk in spite of recent development in engine technology.

Diesel exhaust particles (DEP) contain elemental carbon, organic compounds including Polyaromatic hydrocarbons (PAHs), metals, and other trace compounds. Diesel exhaust is complex mixture of thousands of chemicals. Over forty air contaminants are recognized as toxicants, such as carcinogens. Most diesel exhaust particles have aerodynamic diameters falling within a range of 0.1 to 0.25 µm. DEP was classified as a definite human carcinogen (group 1) by the International Agency for Research on Cancer at 2012 based on recently sufficient epidemiological evidence for lung cancer. Significant decreases in DEP and other diesel exhaust constituents will not be evident immediately, and outworn diesel car having longer mileage still threatens health of people in spite of recent remarkable development in diesel engine technology. Policy change in South Korea, such as introduction of diesel taxi, may raise health risk of air pollution in metropolitan area with these limitations of diesel engine. To protect people against DEP in South Korea, progressive strategies are needed, including disallowance of diesel taxi, more strict regulation of diesel engine emission, obligatory diesel particulate filter attachment in outworn diesel car, and close monitoring about health effects of DEP.

The Cohort for Childhood Origin of Asthma and allergic diseases (COCOA) study: design, rationale and methods.

BACKGROUND: This paper describes the background, aim, and design of a prospective birth-cohort study in Korea called the COhort for Childhood Origin of Asthma and allergic diseases (COCOA). COCOA objectives are to investigate the individual and interactive effects of genetics, perinatal environment, maternal lifestyle, and psychosocial stress of mother and child on pediatric susceptibility to allergic diseases. METHODS/DESIGN: The participants in COCOA represents a Korean inner-city population. Recruitment started on 19 November, 2007 and will continue until 31 December, 2015. Recruitment is performed at five medical centers and eight public-health centers for antenatal care located in Seoul. Participating mother-baby pairs are followed from before birth to adolescents. COCOA investigates whether the following five environmental variables contribute causally to the development and natural course of allergic diseases: (1) perinatal indoor factors (i.e. house-dust mite, bacterial endotoxin, tobacco smoking, and particulate matters 2.5 and 10), (2) perinatal outdoor pollutants, (3) maternal prenatal psychosocial stress and the child's neurodevelopment, (4) perinatal nutrition, and (5) perinatal microbiome. Cord blood and blood samples from the child are used to assess whether the child's genes and epigenetic changes influence allergic-disease susceptibility. Thus, COCOA aims to investigate the contributions of genetics, epigenetics, and various environmental factors in early life to allergic-disease susceptibility in later life. How these variables interact to shape allergic-disease susceptibility is also a key aim.The COCOA data collection schedule includes 11 routine standardized follow-up assessments of all children at 6 months and every year until 10 years of age, regardless of allergic-disease development. The mothers will complete multiple questionnaires to assess the baseline characteristics, the child's exposure to environmental factors, maternal pre- and post-natal psychological stress, and the child's neurodevelopment, nutritional status, and development of allergic and respiratory illnesses. The child's microbiome, genes, epigenetics, plasma cytokine levels, and neuropsychological status, the microbiome of the residence, and the levels of indoor and outdoor pollutants are measured by standard procedures. DISCUSSION: The COCOA study will improve our understanding of how individual genetic or environmental risk factors influence susceptibility to allergic disease and how these variables interact to shape the phenotype of allergic diseases.

Work-relatedness of lung cancer by smoking and histologic type in Korea.

OBJECTIVES: This study investigated the distribution of causative agents related to occupational lung cancer, their relationships with work, and associations between work-relatedness and the histologic type of lung cancer. METHODS: We used data from the occupational surveillance system in Korea in 2013. In addition, data from 1,404 participants diagnosed with lung cancer were collected through interviews. We included the patients' longest-held job in the analysis. Work-relatedness was categorized as "definite," "probable," "possible," "suspicious," "none," or "undetermined." RESULTS: Among the subjects, 69.3% were men and 30.7% were women. Regarding smoking status, current smokers were the most prevalent (35.5%), followed by non-smokers (32.3%), ex-smokers (32.2%). Regarding the causative agents of lung cancer, asbestos (1.0%) and crystalline silica (0.9%) were the most common in definite work-related cases, while non-arsenical insecticide (2.8%) was the most common in probable cases followed by diesel engine exhaust (1.9%) and asbestos (1.0%). Regarding histologic type, adenocarcinoma was the most common (41.7%), followed by squamous cell carcinoma (21.2%). Among current smokers, squamous cell carcinoma was the most common among definite and probable cases (13.4%), while non-small cell lung cancer was the least common (7.1%). Among non-smokers, squamous cell carcinoma was the most common (21.4%), while the least common was adenocarcinoma (1.6%). CONCLUSIONS: Approximately, 9.5% of all lung cancer cases in Korea are occupational-related lung cancer. Well-known substances associated with lung cancer, such as crystalline silica, asbestos, and diesel engine exhaust, are of particular concern. However, the histologic types of lung cancer related to smoking were inconsistent with previous studies when work-relatedness was taken into account. Future studies are required to clarify the incidence of occupational lung cancer in agricultural workers exposed to non-arsenical insecticides and the associations between work-relatedness and the histologic type of lung cancer.

Corrigendum: Necessity for a National Carcinogen List in Korea, Based on International Harmonization.

[This corrects the article on p. e2013008 in vol. 28, PMID: 23882448.].

Necessity for a national carcinogen list in Korea, based on international harmonization.

Cancer has been the leading cause of death in Korea for the last 30 years. Cancer patients' 5-year survival rate between 2005 and 2009 was 62.0%, representing a highly advanced standard of care, as much as developed countries in the EU and the US. The Korean government formulated its first 10-year plan for cancer control in 1996 and has been carrying out a second 10-year plan for cancer control since 2006. But despite the Korean government's efforts, the cancer burden in Korea continues to increase. Many separate laws have gone into effect concerning the management of carcinogen exposure. However, there are no integrated regulatory laws or management systems against carcinogen exposure in Korea. Dead zones remain where carcinogen exposure cannot be controlled properly in Korea. In this paper, we suggest the need to establish a national carcinogen list based on international harmonization as a prerequisite for a paradigm shift in cancer control policy from treatment to primary prevention.

Blood lead level modifies the association between dietary antioxidants and oxidative stress in an urban adult population.

Oxidative stress may be affected by lead exposure as well as antioxidants, yet little is known about the interaction between dietary antioxidants and blood lead levels (BLL) on oxidative stress level. We investigated the interaction between dietary antioxidants and BLL on oxidative stress level. As part of the Biomarker Monitoring for Environmental Health conducted in Seoul and Incheon, Korea, between April and December 2005, we analysed data from 683 adults (female = 47·4 %, mean age 51·4 (sd 8·4) years) who had complete measures on BLL, dietary intakes and oxidative stress marker (urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG)). Dietary intakes were assessed by a validated semi-quantitative FFQ, BLL was measured using atomic absorption spectrophotometry, and 8-OHdG by ELISA. Multivariate linear regression analyses were used to evaluate the influence of BLL on the association between dietary antioxidants and 8-OHdG. Geometric means of BLL and 8-OHdG concentrations were 4·1 (sd 1·5) µg/dl and 5·4 (sd 1·9) µg/g creatinine, respectively. Increases of vitamins C and E were significantly associated with the decrease of log10 8-OHdG in the adults from the lowest quartile of the BLL group (≤ 3·18 µg/dl, geometric mean = 2·36 µg/dl) than those of the highest quartile BLL group (>5·36 µg/dl, geometric mean = 6·78 µg/dl). Regarding antioxidant-related foods, vegetables excluding kimchi showed a higher inverse relationship with 8-OHdG in the lowest quartile BLL group than the highest group. These findings suggest a rationale for lowering the BLL and increasing the intake of dietary antioxidants in the urban population in Korea.

Effect of environmental tobacco smoke on atopic dermatitis among children in Korea.

The prevalence of atopic dermatitis is increasing in many countries. Several factors are known to be associated with childhood atopic dermatitis. Environmental tobacco smoke (ETS) is one of the most common indoor pollutants, and children are more vulnerable to ETS exposure than adults are. In this study, the possible association of ETS with atopic dermatitis was evaluated in 7030 individuals aged 6-13 years who participated in the Children's Health and Environment Research study. In addition, predictive factors, such as the allergic history of the parents, children's immunoglobulin E levels and children's history of rhinitis and its association with dermatitis, were assessed. After adjustment for possible confounding variables, atopic dermatitis was found to be highly correlated with ETS, especially among children whose mothers had smoked during pregnancy and/or in the first year after birth (OR=2.06, 95% CI: 1.01-4.22). In conclusion, our results show that childhood exposure to ETS is a major risk factor for atopic dermatitis.