Search

Background: Children may be exposed to harmful chemicals from their products. Accurate exposure factors are critical for exposure assessment of children's products. Product usage pattern parameters are relatively limited compared with the chemical concentration, children's physiological and behavioral parameters., Objective: The aim of this study was to determine nationally representative Korean exposure factors for the usage patterns of children's products by sex, age, and season., Methods: Using proportional quota sampling, a survey of 10,000 households with children aged 0-12 years was conducted twice, once in summer and winter. The children's ages were divided into four groups: infant (0-2 years old), toddler (3-6), lower-grade elementary student (7-9), and higher-grade elementary student (10-12). Data on exposure factors such as use rate, use frequency, and use duration of 57 children's products were collected., Results: The 57 products were classified into five categories: baby products (13), toys (12), daily products (10), sporting goods (8), and stationery (14). The use rates of products in the daily products and stationery category were >90% in both seasons. Two of the 57 products showed significant sex differences in all three exposure factors (p < 0.001). Twenty-five of the 44 non-baby products showed significant age differences for all three exposure factors. Twenty-three of the 57 products varied significantly with season for all three exposure factors., Impact: This study generated a nationally representative exposure factor database for the usage patterns of children's products in Korea. The exposure factors for 57 children's products were investigated through twice survey with quota sampling with each 10,000 children nationwide. Sex, age, and seasonal differences for children's products were identified. These accurate exposure factors by sex, age, and season can be used as input parameters for refined exposure assessment., Competing Interests: Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Usage patterns of consumer products (CP) must be determined for accurate exposure assessments. The purpose was to quantitatively estimate the uncertainty in exposure factors of CP according to various sample sizes. The uncertainty was calculated based on exposure factors of 3,333 participants representing the Korean population referred to as the 'parent population'. Small subsamples of participants randomly selected from the parent population were used to evaluate the exposure factors of 13 CPs. Exposure factors were compared with the corresponding values from the parent population. For all exposure factors, the ratio of the mean values of the 75th percentile of the subsamples to the values of the parent population became closer to 1 as the subsample size increased. For frequency of use factor, the ratio was between 0.9 and 1.1 with sample size of 100 except household bleach and trigger-type bathroom cleaner. For amount of use factor, the ratio was between 0.9 and 1.1 with sample size of 100 except body wash, household bleach, and glass cleaner. These results showed the quantitative uncertainty of exposure factor estimations according to various sample sizes. A sample size of at least 100 subjects should be collected for estimation of exposure factors for most CP., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

To estimate realistic exposure to a chemical, the aggregate exposure from multiple consumer products should be considered. A receptor-based aggregate exposure assessment was conducted according to individuals' exposure factors and simultaneous use patterns including co-use and non-use. A product-based aggregate exposure assessment was conducted by product usage rates of population and users' exposure factors. Two aggregate exposure assessments were compared. Exposure factors for 31 cosmetic products were collected by face-to-face interviews with 1001 members of the Korean population through national representative sampling. The concentrations of phthalates in 214 cosmetic products were analyzed by GC-MS-MS. The average aggregate exposure dose (AED) determined by the receptor-based method for di(2-ethylhexyl)phthalate (DEHP), di-n-butyl phthalate (DnBP), and diethyl phthalate (DEP) were 0.68 ± 0.87, 1.08 ± 5.71, and 2.47 ± 9.05 μg/kg/day, respectively. The cosmetics that contributed most to the receptor-based AED were skin care and body care products for DEHP, nail care products for DnBP, and fragrance and hair care products for DEP. The young female group showed the highest exposure. The product-based aggregate exposure assessment method underestimated high exposure but overestimated average exposure for DnBP and DEP. The receptor-based aggregate exposure assessment method would be used to determine high exposure groups., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The Korea Simulation Exposure Model for fine particulate matter (PM 2.5 ) (KoSEM-PM) was developed to estimate population PM 2.5 exposure in Korea. The data were acquired based on 59,945 min of the actual microenvironmental PM 2.5 measurements and on the time⁻activity patterns of 8072 residents of Seoul. The aims of the study were to estimate daily PM 2.5 exposure of Seoul population, and to determine the characteristics of a high exposure group. KoSEM-PM estimated population exposures by applying the PM 2.5 distribution to the matching time⁻activity patterns at 10-min intervals. The mean personal PM 2.5 exposure level of the surveyed subjects in Seoul was 26.0 ± 2.7 µg/m³ (range: 21.0⁻40.2 µg/m³) in summer. Factors significantly associated with high exposure included day of the week, age, industry sector, job type, and working hours. Individuals surveyed on Saturdays were more likely to be in the high exposure group than those surveyed on weekdays and Sundays. Younger, non-office-working individuals with longer working hours were more likely to be in the high exposure group. KoSEM-PM could be a useful tool to estimate population exposure levels to other region in Korea; to expand its use, microenvironmental measurements are required for other region in Korea.

Ambient particulate matter (PM) concentrations at monitoring stations were often used as an indicator of population exposure to PM in epidemiological studies. The correlation between personal exposure and ambient concentrations of PM varied because of diverse time-activity patterns. The aim of this study was to determine the relationship between personal exposure and ambient concentrations of PM 10 and PM 2.5 with minimal impact of time-activity pattern on personal exposure. Performance of the MicroPEM, v3.2 was evaluated by collocation with central ambient air monitors for PM 10 and PM 2.5 . A field technician repeatedly conducted measurement of 24 h personal exposures to PM 10 and PM 2.5 with a fixed time-activity pattern of office worker over 26 days in Seoul, Korea. The relationship between the MicroPEM and the ambient air monitor showed good linearity. Personal exposure and ambient concentrations of PM 2.5 were highly correlated with a fixed time-activity pattern compared with PM 10 . The finding implied a high infiltration rate of PM 2.5 and low infiltration rate of PM 10 . The relationship between personal exposure and ambient concentrations of PM 10 and PM 2.5 was different for high level episodes. In the Asian dust episode, staying indoors could reduce personal exposure to PM 10 . However, personal exposure to PM 2.5 could not be reduced by staying indoors during the fine dust advisory episode.

Background: In a multi-unit housing (MUH) complex, secondhand smoke (SHS) can pass from one living space to another. The aim of this study was to determine the prevalence of SHS incursion, and to establish the relationship between SHS incursion and socio-demographic and built environmental factors in MUH in Korea., Methods: A population-based sample of 2600 residents (aged ≥19 years) living in MUH from across the city of Seoul, Korea, was obtained through a web-based selection panel. The residents completed a questionnaire detailing socio-demographic factors, smoking status, frequency of SHS incursion, and built environmental factors. The presence of a personal smoke-free home rule was determined by residents declaring that no one smoked inside the home., Results: Of the 2600 participants, non-smoking residents who lived in homes with a personal smoke-free rule were selected for further analysis (n = 1784). In the previous 12 months, 74.7% of residents had experienced SHS incursion ≥1 times. A multivariate ordinal logistic regression analysis indicated that residents who spent more time at home, lived with children, supported the implementation of smoke-free regulations in MUH, lived in small homes, lived in homes with natural ventilation provided by opening a front door or the windows and front door, and lived in homes with more frequent natural ventilation were more likely to report SHS incursion into their homes., Conclusions: The majority of the non-smoking residents experienced SHS incursion, even with a personal smoke-free rule in their homes. A smoke-free policy in MUH is needed to protect residents from SHS exposure when they are at home.

Time location patterns are a significant factor for exposure assessment models of air pollutants. Factors associated with time location patterns in urban populations are typically due to high air pollution levels in urban areas. The objective of this study was to determine the seasonal differences in time location patterns in two urban cities. A Time Use Survey of Korean Statistics (KOSTAT) was conducted in the summer, fall, and winter of 2014. Time location data from Seoul and Busan were collected, together with demographic information obtained by diaries and questionnaires. Determinants of the time spent at each location were analyzed by multiple linear regression and the stepwise method. Seoul and Busan participants had similar time location profiles over the three seasons. The time spent at own home, other locations, workplace/school and during walk were similar over the three seasons in both the Seoul and Busan participants. The most significant time location pattern factors were employment status, age, gender, monthly income, and spouse. Season affected the time spent at the workplace/school and other locations in the Seoul participants, but not in the Busan participants. The seasons affected each time location pattern of the urban population slightly differently, but overall there were few differences., Competing Interests: The authors declare no conflict of interest.

With support from the Korean Ministry of the Environment (ME), our interdisciplinary research staff developed the COnsumer Product Exposure and Risk assessment system (COPER). This system includes various databases and features that enable the calculation of exposure and determination of risk caused by consumer products use. COPER is divided into three tiers: the integrated database layer (IDL), the domain specific service layer (DSSL), and the exposure and risk assessment layer (ERAL). IDL is organized by the form of the raw data (mostly non-aggregated data) and includes four sub-databases: a toxicity profile, an inventory of Korean consumer products, the weight fractions of chemical substances in the consumer products determined by chemical analysis and national representative exposure factors. DSSL provides web-based information services corresponding to each database within IDL. Finally, ERAL enables risk assessors to perform various exposure and risk assessments, including exposure scenario design via either inhalation or dermal contact by using or organizing each database in an intuitive manner. This paper outlines the overall architecture of the system and highlights some of the unique features of COPER based on visual and dynamic rendering engine for exposure assessment model on web.

Accurately measuring the usage patterns of consumer products (CPs) is important to conduct realistic exposure assessments. We determined the exposure factors for 18 consumer products: household bleach, mold stain remover, all-purpose cleaner, washing machine cleaner, air conditioner cleaner, glass cleaner, drain cleaner, adhesive remover, liquid snow chain, tire shine spray, wheel cleaner, rain repellent, car wax spray, leather polish, furniture polish, anti-fog product, fabric waterproofing spray, and rust inhibitor. Field survey staff visited homes and collected product use information via face-to-face interviews. In total, 10,000 participants (5010 men and 4990 women) aged 15 years and older completed the questionnaire. Household bleach had the highest use rate of 47.4% and use rates for the other products ranged from 0.8 to 21.7%. The use rates of many CPs differed by age group and gender. Many household cleaning products were used regularly, but some products, such as air conditioner cleaner and liquid snow chain, were used in specific seasons or for specific purposes; therefore, they were used less frequently compared to cleaning products. These exposure factor data will be useful as input data for exposure and risk assessments and setting safety guidelines., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Unlabelled: The objective was to determine secondhand smoke (SHS) exposure with and without smoke-free laws in urban and rural communities. The research hypothesis was that SHS exposure in public places could be improved by smoke-free law regardless of urban and rural status. Indoor air quality in hospitality venues was assessed in 53 communities (16 urban and 37 rural) before smoke-free laws; 12 communities passed smoke-free laws during the study period. Real-time measurements of particulate matter with 2.5 µm aerodynamic diameter or smaller (PM2.5) were taken 657 times from 586 distinct venues; about 71 venues had both pre- and post-law measurements. Predictors of log-transformed PM2.5 level were determined using multilevel modeling. With covariates of county-level percent minority population, percent with at least high school education, adult smoking rate, and venue-level smoker density, indoor air quality was associated with smoke-free policy status and venue type and their interaction. The geometric means for restaurants, bars, and other public places in communities without smoke-free policies were 22, 63, and 25 times higher than in those with smoke-free laws, respectively. Indoor air quality was not associated with urban status of venue, and none of the interactions involving urban status were significant. SHS exposure in public places did not differ by urban/rural status. Indoor air quality was associated with smoke-free law status and venue type., Implications: This study analyzed 657 measurements of indoor PM2.5 level in 53 communities in Kentucky, USA. Although indoor air quality in public places was associated with smoke-free policy status and venue type, it did not differ by urban and rural status. The finding supports the idea that population in rural communities can be protected with smoke-free policy. Therefore, it is critical to implement smoke-free policy in rural communities as well as urban areas.

An accurate understanding of the usage patterns of consumer products is important for realistic exposure assessment. Since such patterns differ by country, a Korean national database for exposure factors is needed. We determined the exposure factors of 10 consumer products (face cleanser, toothpaste, shampoo, hair conditioner, body wash, dish and laundry detergents, fabric deodorizer, antistatic spray, and shoe polish. Field survey staff visited homes and collected product use information by questionnaire. In total, 816 men and 2517 women aged 15 years and older from 2500 households completed the questionnaire. Field technicians also re-visited 85 households to investigate the circumstances of use and the reliability of the questionnaire data. Greater than 97% of the sampled population reported use of toothpaste and shampoo. Hair conditioner, body wash, and face cleanser were used by ~60% of the population and by specific age groups and genders. The amount of consumer products used was comparable between that reported in the questionnaire and that measured directly during house visits, and the ratios of usage amounts ranged from 0.75 to 1.69. The exposure factor data obtained from this study could be useful for regulatory agencies when setting safety guidelines for product use., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

There are few studies measuring exposure to outdoor tobacco smoke (OTS). Tobacco users often gather at the boundaries of tobacco-free campuses, resulting in unintended consequences. The objective of this study was to measure exposure levels from OTS on sidewalks bordering a tobacco-free university campus. Data were collected while walking along a sidewalk adjacent to a medium traffic road between May and August 2011. Monitoring occurred during "background," "stop," and "walk-through" conditions at and near hot spot area to measure fine particulate matter (< 2.5 microm; PM2.5) from OTS using a portable aerosol monitor The average PM2.5 levels during stop and walk-through conditions were significantly higher than during background conditions. PM2.5 peak occurrence rate and magnitude of peak concentration were significantly different depending on smoking occurrence. The peak occurrence rate during the stop condition was 10.4 times higher than during the background condition, and 3.1 times higher than during the walk-through condition. Average peak PM2.5 concentrations during the stop condition were 48.7% higher than during the background condition. In conclusion, individuals could be exposed to high levels of PM2.5 when stopping or even passing by smokers outdoors at the perimeter of tobacco-free campuses. The design and implementation of tobacco-free campus policies need to take into account the unintended consequences of OTS exposure at the boundaries. Implications: In this study, outdoor tobacco smoke (OTS) exposure was measured at the perimeter of tobacco-free campus. OTS exposure could be determined by peak analysis. Peak occurrence rate and peak concentration for OTS exposure were identified by using peak analysis. People could be exposed to high levels of PM2.5 when standing or even passing by smokers at the perimeter of tobacco-free campus. OTS exposure measurement in other outdoor locations with smokers is needed to support outdoor smoking regulation.

The effects of particulate pollutants on lung function in children with atopic dermatitis (AD) remain to be determined. The authors investigated the short-term effects of ambient particles on peak expiratory flow rate (PEFR) in 84 children with and without AD. Daily particulates less than 10, 2.5, and 1 μm (PM(10), PM(2.5), and PM(1)) and number concentrations of submicron particles were measured. The authors observed elevated levels of PM(10), PM(2.5), and PM(1), and accumulation-mode particles were associated with decreased PEFR in children with AD. The PEFR decrements were -2.89 L/min (95% confidence interval [CI], -4.93 to -0.89) for an interquartile-range increase of previous-day PM(10), -2.79 L/min (95% CI, -4.89 to -0.69) for PM(2.5), and -2.71 L/min (95% CI, -4.81 to -0.61) for PM(1). These results suggest that ambient fine particles may affect the pulmonary function in children with AD. The respiratory health of children with atopic skin disorders renders them more vulnerable to ambient particles than healthy subjects.

Background: Secondhand smoke accounts for a considerable proportion of deaths due to tobacco smoke. Although the existing laws ban indoor smoking in public places in Sri Lanka, the level of compliance is unknown., Methods: Fine particulate matter (PM(2.5)) levels in 20 public places in Colombo, Sri Lanka were measured by a PM monitor (Model AM510-SIDEPAK Personal Aerosol Monitor). Different types of businesses (restaurants, bars, cafés, and entertainment venues) were selected by purposive sampling. Only the places where smoking was permitted were considered., Results: The average indoor PM(2.5) ranged from 33 to 299 µg/m(3). The average outdoor PM(2.5) ranged from 18 to 83 µg/m(3). The indoor to outdoor PM(2.5) ratio ranged from 1.05 to 14.93. In all venues, indoor PM(2.5) levels were higher than the Sri Lankan ambient PM(2.5) standard of 50 µg/m(3). All indoor locations had higher PM(2.5) levels as compared to their immediate outdoor surroundings., Conclusion: The study highlights the importance of improving ventilation and enforcing laws to stop smoking in public places., (Copyright © 2012 Wiley Periodicals, Inc.)

The objectives of this study were to measure particulate pollution (PM(10), PM(2.5), and PM(1.0)) continuously (24 h/day for 7 day) using real-time exposure monitoring and to estimate total inhalation mass using breathing rate and time-activity. Breathing rates were calculated from measured heart rates. Participants were asked to record a time-activity diary every 15 min. Five microenvironments were defined based on the time-activity diary: home, workplace/school, other indoor, outdoor, and transportation. The average masses of inhaled PM(10) were 530, 316, and 280 μg/day for two office workers, a housewife, and three students, respectively; those of PM(2.5) were 316, 279, and 210 μg/day; and those of PM(1.0) were 251, 264, and 187 μg/day, respectively. We found that home and office/school microenvironments were the main contributors of PM(10), PM(2.5), and PM(1.0) inhaled mass during weekdays and weekends because dwelling time was a determinant factor for inhaled mass. Considering microenvironmental concentration, breathing rate, and dwelling time in each microenvironment, indoor home microenvironments were the largest source of particulate inhalation, followed in order by workplace, transportation, other indoor, and outdoor microenvironments. 34.6% and 69.6% of PM(10) inhalation mass were accumulated in home microenvironments during weekdays and weekends, respectively. The inhaled mass of particulate <1.0 μm (PM(1.0)) in size occupied largest, followed in order by particulate 10-2.5 μm (coarse particle) and 2.5-1.0 μm in size for all occupations.

Traditionally, use of household and personal care products has been collected through questionnaires, which is very time consuming, a burden on participants, and prone to recall bias. As part of the SUPERB Project (Study of Use of Products and Exposure-Related Behaviors), a novel platform was developed using bar codes to quickly and reliably determine what household and personal care products people have in their homes and determine the amount used over a 1-week period. We evaluated the acceptability and feasibility of our methodology in a longitudinal field study that included 47 California households, 30 with young children and 17 with an older adult. Acceptability was defined by refusal rates; feasibility was evaluated in terms of readable bar codes, useful product information in our database for all readable barcodes, and ability to find containers at both the start and end of the week. We found 63% of personal care products and 87% of the household care products had readable barcodes with 47% and 41% having sufficient data for product identification, respectively and secondly, the amount used could be determined most of the time. We present distributions for amount used by product category and compare inter- and intra-person variability. In summary, our method appears to be appropriate, acceptable, and useful for gathering information related to potential exposures stemming from the use of personal and household care products. A very low drop-out rate suggests that this methodology can be useful in longitudinal studies of exposure to household and personal care products.

Residential insecticide usage and actual application details were collected in a population-based sample of 477 households residing within 22 counties in northern California with at least one child of age ≤ 5 years between January 2006 and August 2008. Structured telephone interviews were conducted collecting information on residential use of insecticides, including outdoor sprays, indoor sprays, indoor foggers, applications by professionals, and pet flea/tick control during the previous year. Interviews also covered post-treatment behaviors, which influence post-application exposure levels. Altogether, 80% of the households applied some type of insecticide in the previous year, with half of this population using two or more application methods. Of the households using insecticides, half reported applying insecticides relatively infrequently (<4 times per year), whereas 11-13% reported high frequency of use (>24 times per year). Application frequency was temperature dependent, with significantly more applications during the warmer months from May through October. Spot treatments appeared to be the most prevalent application pattern for sprays. For one out of three of the indoor applications, children played in the treated rooms on the day of the application, and for 40% of the outdoor applications, pets played in the treated area on the day of the application. These findings describing the intensity of insecticide use and accompanying behaviors in families with young children may inform future insecticide exposure modeling efforts, and ultimately, risk assessments.

Information on time spent in microenvironments has a critical role for personal exposure to environmental pollutants. Unlike several large-scale studies in Western countries, no comprehensive research on time-activity patterns for exposure assessment has been conducted in Korea. We investigated determinants of residential indoor and transportation times of individuals over 10-years old in the Korean population. The population-based study collected time-activity patterns of 31,634 Koreans for two consecutive days. The residential indoor and transportation times were collected for a weekday and a weekend day. The impact of sociodemographic factors on time-activity was assessed using multiple linear regression models. The residential indoor times were 14.23 h for the weekday and 16.13 h for the weekend and shorter than those in Western countries. The transportation times were 1.75 h for the weekday and 1.68 h for the weekend day. The most significant factors in residential indoor time were employment status, age, monthly income, and gender for the weekday and employment status and gender for the weekend day. The factors in transportation were gender, employment status, and monthly income for the weekday and gender, employment status, age, and marriage status for the weekend day. Determinants of the time-activity pattern need to be taken into account in exposure assessment, epidemiological analyses, and exposure simulations, as well as in the development of preventive strategies. As Korean population activity patterns are substantially different from those in Western countries such as USA, Germany, and UK, this information could be critical for exposure assessment in Korea and other Asian countries.

Although ambient particulate pollutants have been shown to exacerbate existing allergic symptoms of mucous membranes including rhinitis and asthma, the effects on skin such as atopic dermatitis in childhood deserve further study. We investigated the effects of urban particulate pollutants including ultrafine particles on atopic severity in children with atopic dermatitis. We included 41 schoolchildren, 8-12 years old, who had been diagnosed with atopic dermatitis. For 67 consecutive days, all of them measured their symptoms in a diary. To assess exposure, the daily ambient mass concentrations of particulate matter less than 10, 2.5 and 1 μm (PM(10), PM(2.5) and PM(1), respectively) and concentrations of submicron particles (0.01- 1 μm) were measured at a local school. The mean mass concentrations of PM(10), PM(2.5) and PM(1) were 74.0, 57.8 and 50.8 μg/m(3), respectively. The mean concentrations were 41,335/cm(3) ultrafine particles (UFPs) and 8577/cm(3) accumulation mode (0.1-1 μm) particles. Significant associations were found between the concentrations of ultrafine particles and the itchiness symptom in children with atopic dermatitis. An interquartile range (IQR) increase in previous day ultrafine particles concentration (IQR: 28-140/m(3)) was significantly associated with a 3.1% (95% confidence interval, 0.2-6.1) increase in the itch symptom score for children with atopic dermatitis. The results suggested that the concentration of ambient ultrafine particles may exacerbate skin symptoms in children with atopic dermatitis., (Copyright © 2011. Published by Elsevier Inc.)

Given the concern over the potential for health risks associated with certain ingredients (e.g., phthalates) in personal care products, usage patterns of ∼30 types of personal care products (e.g., shampoo, sunscreen, fragrance, etc.) were collected in 604 California households through a telephone interview. Preferences in selecting products, e.g., scented or unscented, aerosol, and brand loyalty, were also investigated. Participants were recruited in three age groups, children (mostly preschoolers), their parents, and adults age 55 or older. Use frequencies of various product types varied by sex, age group, race, education, and climatic region. Product use by parent and child from the same household were correlated. Use frequencies of products in the same class (e.g., skincare) were moderately correlated, which may impact aggregate exposures. Use frequencies observed in this study were generally in the same range as those reported in the EPA Exposure Factor Handbook, but we found differences for some individual products. Our study provides additional data on population-based usage patterns of a large collection of commonly used personal care products pertaining to several age groups and socio-demographic strata. This information will be valuable for exposure and risk assessments., (Copyright © 2010 Elsevier Ltd. All rights reserved.)

Background: Exposure to toxic chemicals in the home is a growing concern. This report presents an overview of the recruitment, methods for data collection, instruments used to collect data, and participant demographics for a study examining behaviors that influence exposure to environmental toxins in the home environment, also known as SUPERB (Study of Use of Products and Exposure Related Behaviors)., Methods: The methods involved three different platforms: telephone interviews, internet-based surveys, and home-based monitoring. The purposes of SUPERB were: first, to compare data collection platforms with regard to feasibility, acceptability and reliability; and second, to provide longitudinal population-based data characterizing seasonal and long-term changes in exposure-related behaviors including food consumption, temporal-spatial activity, and household product use., Results: Two cohorts of households were enrolled: families (one parent and one child) from northern California and older individuals (age 55+) from central California. Parents (n = 499) in Northern California families were on average 36 years of age, 47.1% were Latino or nonwhite, and 10.2% took the survey in Spanish. Most of the children enrolled (n = 566) were under 6 years (82.7%). The older adults enrolled (n = 156) were, on average, 66 years of age and 23.7% were Latino or nonwhite, but only 2.6% completed the survey in Spanish., Conclusions: We found that oversampling was successful in improving recruitment of under-represented subgroups, such as those with low education, thereby increasing diversity of our study sample. Protocols that minimize participant time, e.g., use of bar scanners and scales rather than questionnaires regarding use of household products, and the implementation of these protocols by staff who built relationships of trust, resulted in high retention over a longitudinal data collection scheme. A relatively small fraction of those who volunteer for longitudinal internet surveys are consistent in filling them out. Future reports will provide critical information on cross-sectional, seasonal and longitudinal patterns of exposure related behaviors in young children, parents of young children, and older adults.

Urinary 1-hydroxypyrene (1-OHP) is a biomarker of exposure to polycyclic aromatic hydrocarbons (PAH). Effect of residence on children's PAH exposure was reported among children living near a polluted area. Instead of a snapshot assessment, however, a temporal history of exposure characteristics needs to be assessed in the studies of chronic disease development such as cancer. The urinary 1-OHP measurements were repeated to determine regional effect of ambient air pollution on 1-OHP levels over extended periods. Two sites were chosen: (a) one site located near the steel mill ("nearby" site) and (b) the other site located at a longer distance from the mill ("remote" site). Spot urinary 1-OHP levels were measured from 72 children for 3 consecutive days per month, repeated over 9-month period. Compared with remote site, the nearby site had increased the urinary 1-OHP level by 62.3% [95% confidence interval (95% CI), 39.8-88.3%]. Other statistically significant factors that contributed to the level include sex [16.5% (95% CI, 1.2-34.1%) higher for girls than boys], consumption of charbroiled meat [16.5% (95% CI, 1.1-34.2%) higher], and an increase in PM(10) [10.1% (95% CI, 4.8-15.7%) higher for the interquartile range increment]. Controlling for covariates, the 1-OHP levels were increased in the summer and fall compared with winter. The magnitude of the effects of both seasons had diminished after adjusting for PM(10). This is the first report providing seasonal and regional contributors to environmental PAH exposure, assessed by urinary 1-OHP, with higher 1-OHP levels during summer when ambient pollution was also high.

The authors assessed the impacts of two different smoke-free laws on indoor air quality. They compared the indoor air quality of 10 hospitality venues in Lexington and Louisville, Kentucky, before and after the smoke-free laws went into effect. Real-time measurements of particulate matter with aerodynamic diameter of 2.5 microm or smaller (PM2.5) were made. One Lexington establishment was excluded from the analysis of results because of apparent smoking violation after the law went into effect. The average indoor PM2.5 concentrations in the nine Lexington venues decreased 91 percent, from 199 to 18 microg/m3. The average indoor PM2.5 concentrations in the 10 Louisville venues, however, increased slightly, from 304 to 338 microg/m3. PM2.5 levels in the establishments decreased as numbers of burning cigarettes decreased. While the Louisville partial smoke-free law with exemptions did not reduce indoor air pollution in the selected venues, comprehensive and properly enforced smoke-free laws can be an effective means of reducing indoor air pollution.

Chronic exposure is often assessed using a single measurement per individual or group. However, daily levels of personal exposure can vary greatly. Chronic exposure classification by a single measurement could be significantly affected by the interpersonal and daily variations of exposures. The purpose of this study is to determine the effect of using a single personal exposure measurement on estimating long-term exposure. This study used measurements of consecutive 14 daily personal exposures to nitrogen dioxide (NO(2)) and sulfur dioxide (SO(2)) of 50 individuals in Yeochun, Korea. The daily personal exposures were measured by passive samplers. Personal exposure to NO(2) was associated with gas cooking, and personal exposure to SO(2) was associated with ambient air pollution. Mixed effects models indicated that daily variability was greater than interpersonal variability for both the pollutants. Effectiveness of using single-day personal measurements for long-term population mean exposure was supported by relatively consistent daily population averages, but multiple-day measurements might be warranted for characterizing individual exposures or high-end population exposures such as the 95th percentile. Although classification of high and low exposure groups by 1-day exposure and by 14-day exposure produced similar group totals, 20% of individual NO(2) exposures and 31% of individual SO(2) exposures were misclassified using 1-day exposures. Average values of 1-day exposure and 14-day exposure were significantly different, but the difference decreased by an increase in the number of measurements for the short-term exposure. The findings were similar for both NO(2) and SO(2), although the two air pollutants have different sources and behaviors.

An ozone (O3) exposure study was conducted in Nashville, TN, using passive O3 samplers to measure six weekly outdoor, indoor, and personal O3 exposure estimates for a group of 10- to 12-yr-old elementary school children. Thirty-six children from two Nashville area communities (Inglewood and Hendersonville) participated in the O3 sampling program, and 99 children provided additional time-activity information by telephone interview. By design, this study coincided with the 1994 Nashville/Middle Tennessee Ozone Study conducted by the Southern Oxidants Study, which provided enhanced continuous ambient O3 monitoring across the Nashville area. Passive sampling estimated weekly average outdoor O3 concentrations from 0.011 to 0.O30 ppm in the urban Inglewood community and from 0.015 to 0.042 ppm in suburban Hendersonville. The maximum 1- and 8-hr ambient concentrations encountered at the Hendersonville continuous monitor exceeded the levels of the 1- and 8-hr metrics for the O3 National Ambient Air Quality Standard. Weekly average personal O3 exposures ranged from 0.0013 to 0.0064 ppm (7-31% of outdoor levels). Personal O3 exposures reflected the proportional amount of time spent in indoor and outdoor environments. Air-conditioned homes displayed very low indoor O3 concentrations, and homes using open windows and fans for ventilation displayed much higher concentrations.

Background: In a multi-unit housing (MUH) complex, secondhand smoke (SHS) can pass from one living space to another. The aim of this study was to determine the prevalence of SHS incursion, and to establish the relationship between SHS incursion and socio-demographic and built environmental factors in MUH in Korea.Methods: A population-based sample of 2600 residents (aged ≥19 years) living in MUH from across the city of Seoul, Korea, was obtained through a web-based selection panel. The residents completed a questionnaire detailing socio-demographic factors, smoking status, frequency of SHS incursion, and built environmental factors. The presence of a personal smoke-free home rule was determined by residents declaring that no one smoked inside the home.Results: Of the 2600 participants, non-smoking residents who lived in homes with a personal smoke-free rule were selected for further analysis (n = 1784). In the previous 12 months, 74.7% of residents had experienced SHS incursion ≥1 times. A multivariate ordinal logistic regression analysis indicated that residents who spent more time at home, lived with children, supported the implementation of smoke-free regulations in MUH, lived in small homes, lived in homes with natural ventilation provided by opening a front door or the windows and front door, and lived in homes with more frequent natural ventilation were more likely to report SHS incursion into their homes.Conclusions: The majority of the non-smoking residents experienced SHS incursion, even with a personal smoke-free rule in their homes. A smoke-free policy in MUH is needed to protect residents from SHS exposure when they are at home. [ABSTRACT FROM AUTHOR]

Introduction: In South Korea, computer game rooms are subject to regulations mandating a designated nonsmoking area pursuant to Article 7 of the Enforcement Rules of the National Health Promotion Act; nonsmoking areas must be enclosed on all sides by solid and impermeable partitions. Methods: Using PM2.5 monitors (SidePak AM510) and airborne nicotine monitors, we measured concentrations in smoking and nonsmoking areas to examine whether separation of the nonsmoking areas as currently practiced is a viable way to protect the nonsmoking area from secondhand smoke exposure. Convenient samplings were conducted at 28 computer game rooms randomly selected from 14 districts in Seoul, South Korea between August and September 2009. Results: The medians (interquartile range) of PM2.5 concentrations in smoking and nonsmoking areas were 69.3 μg/m3 (34.5–116.5 μg/m3) and 34 μg/m3 (15.0–57.0 μg/m3), while those of airborne nicotine were 0.41 μg/m3 (0.25–0.69 μg/m3) and 0.12 μg/m3 (0.06–0.16 μg/m3), respectively. Concentrations of airborne nicotine and PM2.5 in nonsmoking areas were substantially positively associated with those in smoking areas. The Spearman correlation coefficients for them were 0.68 (p = .02) and 0.1 (p = 0.7), respectively. According to our modeling result, unit increase of airborne nicotine concentration in a smoking area contributed to 7 (95% CI = 2.5–19.8) times increase of the concentration in the adjacent nonsmoking area after controlling for the degree of partition left closed and the indoor space volume. Conclusions: Our study thus provides evidence for the introduction of more rigorous policy initiatives aimed at encouraging a complete smoking ban in such venues. [ABSTRACT FROM AUTHOR]