Because particulate matter (PM) and asthma are closely related, the prevalence of school absence among adolescents with asthma can be affected by the concentration of PM. We aimed to investigate the relationship between school absences due to asthma and the total number of days that the PM concentration exceeded the standard.

We used the data from the 16th Korea Youth Risk Behavior Survey and the PM levels of 17 metropolitan cities and provinces gathered from the AirKorea. Information on the characteristics of asthmatic adolescents and the prevalence of school absence was obtained using a questionnaire, while the PM levels based on the total number of days with poor and very poor PM grades were collected from the AirKorea website. Both χ² test and logistic regression analysis were performed using the weights presented in the original dataset.

In the case of particulate matter of 10 microns in diameter or smaller (PM₁₀), the odds ratio (OR) after adjusting for confounders (sex, school year, body mass index, smoking history, diagnosis of allergic rhinitis, diagnosis of atopic dermatitis and city size) was 1.07 (95% confidence interval [CI]: 1.01–1.13) for absents due to asthma when the total days of poor and very poor grades of PM₁₀ (81 μg/m³ or higher) increased by 1 day. In the analysis of particulate matter of 2.5 microns in diameter or smaller (PM_2.5), the OR after adjusting for confounders was 1.01 (95% CI: 1.00–1.03) for absents due to asthma when the total number of days with poor and very poor PM_2.5 grades (36 μg/m³ or higher) increased by 1 day.

A significant association was observed between the total number of days of poor and very poor PM₁₀ and PM_2.5 grades and school absence due to asthma; PM can cause asthma exacerbation and affect the academic life.

Adolescent smoking and drinking are influenced by parental supervision. This study aimed to investigate the gap in adolescent smoking and drinking experience rates and age at initiation according to maternal working hours.

Data from 1,580 adolescents aged 12–18 years and 1,172 working mothers of double-parent or single-mother households were selected from the Korean National Health and Nutrition Examination Survey (KNHANES) VI & VII data. Figures on adolescents' smoking and drinking rates and their ages at imitation were used. Maternal working hours were divided into < 40 hours, 40–52 hours, and > 52 hours to analyze whether smoking and drinking experience rates and age at initiation differ according to maternal working hours and by the child's sex. Maternal age, education level, household income, occupation, shift work, current smoking status, monthly drinking frequency and child's obesity, stress recognition and depressive mood were adjusted for in the statistical analyses.

The odds for adolescents' smoking behavior were significantly higher with increasing maternal working hours in boys but not in girls. The odds for adolescents' drinking behavior were not significantly higher in both boys and girls. Regardless of the child's sex, there were no significant differences in the age of smoking and drinking initiation according to maternal working hours.

Adolescents of mothers who work long hours are at a higher risk of being exposed to smoking. Thus, our society needs to share the burden of raising children, which is concentrated on women, and employers and governments should support policies that can help prevent long working hours.

The aim of this study is to find the association between mothers’ working hours and obesity of their children according to children’s age and gender.

This study used data from the second and third year of KNHANES IV and the first year in KNHANES V (2008–2010). We calculate odds ratio (OR) and 95% confidence interval (CI) by using survey logistic regression to assess association of mother’s working hours with overweight or obesity of her children. The model was adjusted with household income, mothers’ education and obesity and mothers’ job characteristics.

13–18 aged boys whose mothers worked under 40 hours per week were higher risk for obesity and overweight (including obesity) than 13–18 aged boys whose mothers worked 40–48 hours. 6–12 aged girls whose mothers worked 49–60 hours per week were more overweight (including obesity) than girls whose mothers worked 40–48 hours per week. 13–18 aged girls whose mothers worked over 60 hours were more overweight (including obesity) than the reference.

This study showed that girls’ obesity was associated with mothers’ long working hours. Long working hours can influence health of workers’ family.