OBJECTIVES: As public concern on possible harmful effects of mobile phone in children has been raised, information of epidemiological characteristics of mobile phone use in children and adolescents will be essential for public health policy. METHODS: Using three databases (n=21,693) collected from 2008 to 2011, we examined characteristics of mobile phone ownership and use, and socioeconomic positions (SEP) in Korean children and adolescents. RESULTS: The ownership rate and the amount of mobile phone use were higher in females than males, in higher school grades than lower grades, and at 2011 than 2008. The average age of first mobile phone ownership was shown to decrease from 12.5 years in currently high school students to 8.4 years in currently elementary school students at 2011. More than 90% of children in the 5th grade owned a mobile phone. More children owned a mobile phone in lower SEP communities than in higher SEP. Children with parents educated less than those with parents educated more were more likely to own and use mobile phone. CONCLUSIONS: Considering the epidemiological characteristics of mobile phone use, precautionary measures to prevent unnecessary exposure to mobile phones are needed in children and adolescents.
Adolescent* ; Cellular Phone* ; Child* ; Female ; Humans ; Male ; Ownership* ; Parents ; Public Health

OBJECTIVES: We aimed to assess the radiation exposure for epidemiologic investigation in residents exposed to radiation from roads that were accidentally found to be contaminated with radioactive cesium-137 (137Cs) in Seoul. METHODS: Using information regarding the frequency and duration of passing via the 137Cs contaminated roads or residing/working near the roads from the questionnaires that were obtained from 8875 residents and the measured radiation doses reported by the Nuclear Safety and Security Commission, we calculated the total cumulative dose of radiation exposure for each person. RESULTS: Sixty-three percent of the residents who responded to the questionnaire were considered as ever-exposed and 1% of them had a total cumulative dose of more than 10 mSv. The mean (minimum, maximum) duration of radiation exposure was 4.75 years (0.08, 11.98) and the geometric mean (minimum, maximum) of the total cumulative dose was 0.049 mSv (<0.001, 35.35) in the exposed. CONCLUSIONS: An individual exposure assessment was performed for an epidemiological study to estimate the health risk among residents living in the vicinity of 137Cs contaminated roads. The average exposure dose in the exposed people was less than 5% of the current guideline.
Epidemiologic Studies* ; Humans ; Korea* ; Radiation Exposure* ; Seoul*

OBJECTIVES: We aimed to assess the radiation exposure for epidemiologic investigation in residents exposed to radiation from roads that were accidentally found to be contaminated with radioactive cesium-137 (137Cs) in Seoul. METHODS: Using information regarding the frequency and duration of passing via the 137Cs contaminated roads or residing/working near the roads from the questionnaires that were obtained from 8875 residents and the measured radiation doses reported by the Nuclear Safety and Security Commission, we calculated the total cumulative dose of radiation exposure for each person. RESULTS: Sixty-three percent of the residents who responded to the questionnaire were considered as ever-exposed and 1% of them had a total cumulative dose of more than 10 mSv. The mean (minimum, maximum) duration of radiation exposure was 4.75 years (0.08, 11.98) and the geometric mean (minimum, maximum) of the total cumulative dose was 0.049 mSv (<0.001, 35.35) in the exposed. CONCLUSIONS: An individual exposure assessment was performed for an epidemiological study to estimate the health risk among residents living in the vicinity of 137Cs contaminated roads. The average exposure dose in the exposed people was less than 5% of the current guideline.
Epidemiologic Studies* ; Humans ; Korea* ; Radiation Exposure* ; Seoul*

BACKGROUND: In 2011, two roads in a residential area in Seoul were found to be contaminated with the radionuclide cesium-137 (137Cs). In response to public concerns, an epidemiological study was conducted. METHODS: The standardized cancer incidence ratios in the affected and neighboring regions were calculated based on the central cancer registry. Households in the region were sampled using the random stratified sampling technique, and questionnaires were administered to family members, via home visit and via students in elementary to high schools. Information on duration of residency and frequency of use of the roads was applied to calculate cumulative radiation exposure dose from the roads, alongside with the reported 137Cs contamination amounts. Information on past medical history, perceived risk, anxiety and psychological stress was also obtained. Of the 31,053 residents, 8,875 were analyzed. To examine possible associations between radiation exposure and health problems, logistic regression adjusted for covariates were performed with consideration of the sampling design, population weight and stratification. RESULTS: No significant association was found between self-informed diseases, including cancers, and estimated radiation exposure dose. According to an increase of radiation level, a significant increase in anxiety in all and a decline in the psychosocial wellbeing of the adults was noted. The risk perception level was higher in the elderly, females, the less educated, and the highest exposed individuals. CONCLUSION: This study provides a basis for risk communication with residents and community environmental health policy.
Adult ; Aged ; Anxiety ; Environmental Health ; Epidemiologic Studies ; Family Characteristics ; Female ; House Calls ; Humans ; Incidence ; Internship and Residency ; Logistic Models ; Radiation Exposure ; Seoul ; Stress, Psychological

PURPOSE: We investigated the prevalence and risk factors of allergic rhinitis (AR), nationwide in random children and adolescents of Korea. METHODS: A modified International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire survey was done in 1,820 children from elementary, middle, and high school nationwide in Korea. The subjects were selected by the stratifying sampling method by school grade and five regions. Current AR was defined as having AR symptoms during the last 12 months with a history of physician-diagnosed AR. Skin prick tests for 18 common allergens were performed. RESULTS: The number of males was 945, and that of females was 875. The mean age of the patients was 12.61+/-3.40 years. The prevalence of current AR and atopic current AR were 29.0% and 18.7%, respectively. Risk factors for current AR were male (adjusted odds ratio [aOR], 1.486; 95% confidence interval [CI], 1.189-1.856), family history of paternal AR (aOR, 3.208; 95% CI, 2.460-4.182), family history of maternal AR (aOR, 3.138; 95% CI, 2.446-4.025), antibiotic use in infancy (aOR, 1.547; 95% CI, 1.228-1.949), mold exposure during infancy (aOR, 1.416; 95% CI, 1.103-1.819), mold exposure during the last 12 months (aOR, 1.285; 95% CI, 1.012-1.630), and sensitization on skin prick tests (aOR, 2.596; 95% CI, 2.055-3.279). Risk factors for atopic current AR were the same as those of current AR, whereas breast-milk feeding (aOR, 0.720; 95% CI, 0.530-0.976) was a protective factor. Sensitized allergens as risk factors for current AR were Dermatophagoides pteronyssinus, Dermatophagoides farina, ragweed, mugwort, oak, alder, birch, Japanese hop, cat, and dog. CONCLUSION: The prevalences of current AR and atopic current AR were 29.0% and 18.7%, respectively. Male, sex parental AR, antibiotic use in infancy, mold exposure during the last 12 months, mold exposure during infancy, and atopic sensitization were risk factors for current AR. Breast-milk feeding was a protective factor for atopic current AR. Aeroallergen sensitization was an important risk factor for AR.
Adolescent ; Allergens ; Alnus ; Ambrosia ; Animals ; Artemisia ; Asian Continental Ancestry Group ; Asthma ; Betula ; Cats ; Child ; Dermatophagoides pteronyssinus ; Dogs ; Female ; Fungi ; Humans ; Humulus ; Hypersensitivity ; Korea ; Male ; Odds Ratio ; Parents ; Prevalence* ; Pyroglyphidae ; Rhinitis* ; Risk Factors* ; Skin