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We present trace gas vertical profiles observed by instruments on the NASA DC-8 and at a ground site during the Korea-US air quality study (KORUS) field campaign in May to June 2016. We focus on the region near the Seoul metropolitan area and its surroundings where both anthropogenic and natural emission sources play an important role in local photochemistry. Integrating ground and airborne observations is the major research goal of many atmospheric chemistry field campaigns. Although airborne platforms typically aim to sample from near surface to the free troposphere, it is difficult to fly very close to the surface especially in environments with complex terrain or a populated area. A detailed analysis integrating ground and airborne observations associated with specific concentration footprints indicates that reactive trace gases are quickly oxidized below an altitude of 700 m. The total OH reactivity profile has a rapid decay in the lower part of troposphere from surface to the lowest altitude (700 m) sampled by the NASA DC-8. The decay rate is close to that of very reactive biogenic volatile organic compounds such as monoterpenes. Therefore, we argue that photochemical processes in the bottom of the boundary layer, below the typical altitude of aircraft sampling, should be thoroughly investigated to properly assess ozone and secondary aerosol formation.

Mycotoxins occur singly or as co-contaminants and are primarily present in carbohydrate-rich foods such as cereals and cereal-based products. To effectively monitor mycotoxin co-contamination in cereals and cereal-based products, the simultaneous analysis of mycotoxins and their derivatives is required. Therefore, we coupled cleanup with LC-MS/MS for the rapid and robust quantitation of 35 analytes in wheat samples, including ergot alkaloids (EAs), which are rarely included in such analyses. To investigate the effects of different mycotoxin types on adsorbents, various dispersive solid-phase extraction sorbents were evaluated; a C18 end-capped sorbent exhibited the most effective cleanup performance. The method was validated by analyzing samples fortified with the mycotoxins at three concentration levels. The results exhibited high linearity, high recoveries, and repeatability. The methodology was applied for commercial cereal samples. The cereal samples were found to be 74% contaminated, and two samples measured levels of EAs at 609.63 μg/kg and 294.93 μg/kg, exceeding the limits defined by the EU for rye milling products. These findings highlight the validity of our novel method and the necessity of continuously monitoring mycotoxin levels in cereals to ensure food safety. [ABSTRACT FROM AUTHOR]

Background Despite conflicting findings on the association between socioeconomic status and drinking, little is known about the impact of deprivation as a measure of inequality on alcohol use disorders (AUDs). Methods We used the Korea Welfare Panel Study, a longitudinal survey conducted from 2012 to 2022, and included 1569 Korean adult participants. Deprivation (at least one including food, housing, medical, educational, and credit deprivation) was measured by self-report and divided into four categories according to the change in deprivation experience from the previous year to the following year. AUD was measured using the Korean version of the Alcohol Use Disorders Identification Test scale. Multivariable logistic regression was used to estimate odds ratios and 95% confidence intervals and adjusted for confounders. Results Among 1569 participants, worsened deprivation and consistent deprivation were positively associated with AUD compared to non-deprivation. In particular, worsened deprivation was more likely to be associated with AUD in participants with low household income, high school education level, and economic activity. Conclusion We found that worsened deprivation and consistent deprivation were associated with AUD. Deprivation should be considered as a health policy intervention to improve drinking problems. [ABSTRACT FROM AUTHOR]

South Korea has recently achieved developed country status with the second largest megacity in the world, the Seoul Metropolitan Area (SMA). This study provides insights into future changes in air quality for rapidly emerging megacities in the East Asian region. We present total OH reactivity observations in the SMA conducted at an urban Seoul site (May-June, 2015) and a suburban forest site (Sep, 2015). The total OH reactivity in an urban site during the daytime was observed at similar levels (∼15 s(-1)) to those previously reported from other East Asian megacity studies. Trace gas observations indicate that OH reactivity is largely accounted for by NOX (∼50%) followed by volatile organic compounds (VOCs) (∼35%). Isoprene accounts for a substantial fraction of OH reactivity among the comprehensive VOC observational dataset (25-47%). In general, observed total OH reactivity can be accounted for by the observed trace gas dataset. However, observed total OH reactivity in the suburban forest area cannot be largely accounted for (∼70%) by the trace gas measurements. The importance of biogenic VOC (BVOCs) emissions and oxidations used to evaluate the impacts of East Asian megacity outflows for the regional air quality and climate contexts are highlighted in this study.

Introduction: Adolescents are especially susceptible to the harmful effects of secondhand smoke exposure. Mental health issues may be one of these negative consequences. This study aimed to explore the association between secondhand smoke exposure and anxiety among Korean adolescents. Methods: This study used the nationwide representative cross-sectional data obtained from the 4-year (2020-2023) Korea Youth Risk Behavior Survey. In total, 214514 individuals aged 12–18 years were included in this study (109910 males and 104604 females). Secondhand smoke exposure was assessed based on responses to questions concerning the days they were exposed (at home and in public places), while anxiety levels were measured using the Generalized Anxiety Disorder 7 scale. Multivariable logistic regression analysis divided by sex was performed to explore the association (p=0.0173 for interaction by secondhand smoke exposure and sex), and adjusted odds ratios (ORs) with 95% confidence intervals (CI) were calculated. Results: Among the study population, 8.8% of the male and 15.6% of the female participants had anxiety. After adjusting for covariates, adolescents with secondhand smoke exposure had a higher likelihood of reporting anxiety than those without the exposure (male, OR=1.23; 95% CI: 1.16–1.29; female, OR=1.27; 95% CI: 1.21–1.33). In additional stratified analyses, this association was more prominent among those who were never smokers, were exposed for more days, and had severe levels of anxiety. Conclusions: This study found that secondhand smoke exposure was associated with anxiety in adolescents; hence, proper political interventions to reduce secondhand smoke exposure may be required. [ABSTRACT FROM AUTHOR]

Summary: Obstructive sleep apnea (OSA) is a common sleep disorder characterised by recurrent upper airway collapse during sleep. Alcohol consumption has been linked to an increased risk of OSA due to its effects on the upper airway and body mass index (BMI). We aimed to investigate the correlation between alcohol use disorders and OSA. We used 11,859 participants data from Korean National Health and Nutrition Examination Surveys. The variable of interest was alcohol use disorder, measured using the Alcohol Use Disorders Identification Test, and the dependent variable was the risk of OSA, measured using the Snoring, Tiredness, Observed apnea, high blood Pressure, BMI, age, neck circumference, and male gender questionnaires. Multiple logistic regression was used to assess the association between alcohol use disorder and OSA risk after adjusted analysis. A significant association was found between alcohol use disorder and OSA (adjusted odds ratio [aOR] 2.14, 95% confidence interval [CI] 1.93–2.37). In the unemployed group, those with alcohol use disorder had the highest odds of being at risk of OSA compared with those who did not have this disorder (aOR 2.45, 95% CI 2.04–2.95). The OSA risk increased as the snoring frequency, amount of alcohol consumed, and frequency of binge drinking increased. This study suggests an association between alcohol use disorders and the risk of OSA. The frequency of alcohol consumption, quantity of alcohol consumed, and snoring frequency were associated with the risk of OSA. Therefore, ceasing alcohol consumption is recommended as an effective approach to enhancing sleep quality. [ABSTRACT FROM AUTHOR]

Background: The association between atopic dermatitis and childhood overweight and obesity has been studied extensively, but the results are inconclusive; most studies have focused on body mass index as a measure of obesity, with few investigating the relationship with underweight. Therefore, this study aimed to investigate the association between body mass index levels and atopic dermatitis in Korean adolescents. Methods: 3-year (2019–2021) of Korea Youth Risk Behavior Web-based Survey were used. Body mass index was used to measure obesity and a recent diagnosis within the past year was used as the criterion for atopic dermatitis. Multiple logistic regression analyses were performed to explore the associations. The odds ratios (ORs) and 95% confidence intervals (CIs) were calculated. Results: A total of 144,183 adolescents aged 12–18 years were included in this study (74,704 males and 69,479 females). Over the past year, 5.4% of males and 7.3% of females were diagnosed with atopic dermatitis in the study population. Adolescents with normal weight (males [OR: 1.19, CI: 1.02–1.38]; females [OR: 1.26, CI: 1.10–1.43]) and overweight (males [OR: 1.37, CI: 1.16–1.61]; females [OR: 1.37, CI: 1.19–1.58]) were more likely to develop atopic dermatitis than underweight. Conclusion: Increased degree of obesity may contribute to the development of atopic dermatitis. The normal-weight and obese adolescents had higher likelihood of developing atopic dermatitis compared with the underweight adolescents. [ABSTRACT FROM AUTHOR]