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Chemical characterization and source apportionment of PM2.5 personal exposure of two cohorts living in urban and suburban Beijing
2019
Shang, Jing | Khuzestani, Reza Bashiri | Tian, Jingyu | Schauer, James J. | Hua, Jinxi | Zhang, Yang | Cai, Tianqi | Fang, Dongqing | An, Jianxiong | Zhang, Yuanxun
In the study, personal PM₂.₅ exposures and their source contributions were characterized for 159 subjects living in the Beijing Metropolitan area. The exposures and sources were examined as functions of residential location, season, vocation, cigarette smoking, and time spent outdoors. Sampling was performed for two categories of volunteers, guards and students, that lived in urban and suburban areas of Beijing. Samples were collected using portable PM₂.₅ monitors during summer and winter. Exposure measurements were supplemented with a questionnaire that tracked personal activity and time spent in microenvironments that may have impacted exposures. Simultaneously, ambient PM₂.₅ data were obtained from national network stations located at the Gucheng and Huairouzhen sites. These data were used as a comparison against the personal PM₂.₅ exposures and produced poor correlations between personal and ambient PM₂.₅. These results demonstrate that individual behavior strongly affects personal PM₂.₅ exposure. Six primary sources of personal PM₂.₅ exposure were determined using a positive matrix factorization (PMF) source apportionment model. These sources included Roadway Transport Source, Soil/Dust Source, Industrial/Combustion Source, Secondary Inorganic Source, Cd Source, and Household Heating Source. Averaged across all subjects and seasons, the highest source contribution was Secondary Inorganic Source (24.8% ± 32.6%, AVG ± STD), whereas the largest primary ambient source was determined to be Roadway Transport (20.9% ± 13.6%). Subjects were classified according to the questionnaire and were used to help understand the relationship between personal activity and source contribution to PM₂.₅ exposure. In general, primary ambient sources showed only significant spatial and seasonal differences, while secondary sources differed significantly between populations with different personal behavior. In particular, Cd source was found to be related to smoking exposure and was the most unpredictable source, with significant differences between populations of different sites, vocations, smoking exposures, and outdoor time.
Mostrar más [+] Menos [-]Assessment of ultrafine particles in primary schools: Emphasis on different indoor microenvironments
2019
Slezakova, Klara | Fernandes, Eduardo de Oliveira | Pereira, Maria do Carmo
Due to the negative health impacts, significant efforts have been directed towards investigating ultrafine particle (UFP) exposure in various indoor environments. As children spend approximately one third of their time in schools, educatory environments deserve particular attention; however, majority of past research has focused on UFP assessment in classrooms. Thus, this work aims to expand the characterization of UFP in primary schools by considering different indoor and outdoor school microenvironments and estimating inhalation doses for the respective students (6–11yrs old). Real-time UFP measurements were daily conducted (9:00–17:30) in 20 primary schools in Oporto (January–April 2014; October–February 2015) in classrooms, canteens, gyms, libraries, and concurrently outdoors. Overall, UFP concentrations showed large temporal and spatial variations. For classrooms (n = 73), median UFP (1.56 × 10³–16.8 × 10³ # cm⁻³) were lower than the corresponding levels in ambient air of schools (1.79 × 10³–24.1 × 10³ # cm⁻³). Outdoor emissions contributed to indoor UFP (indoor-to-outdoor ratios I/O of 0.0.30–0.85), but ventilation, room characteristics and its occupancy were identified as important parameters contributing to overall indoor UFP levels. Considering specific indoor school microenvironments, canteens were the microenvironment with the highest UFP levels (5.47 × 10³–36.4 × 10³ # cm⁻³), cooking conducted directly on school grounds resulted in significantly elevated UFP in the respective classrooms (p < 0.05); the lowest UFP were found in libraries (4.45 × 10³–8.50 × 10³ # cm⁻³) mostly due to the limited occupancies. Although students spend majority of their school time in classrooms (66–71%), classroom exposure was not consistently the predominant contributor to school total UFP inhalation dose (29–75%). Outdoor exposure contributed 23–70% of school dose (depending on UFP levels in ambient levels and/or conducted activities) whereas short periods of lunch break accounted for 8–40%. Therefore, when evaluating UFP exposure in educatory settings other microenvironments beyond classrooms should be an integral part of the study.
Mostrar más [+] Menos [-]Manganese and lead levels in settled dust in elementary schools are correlated with biomarkers of exposure in school-aged children
2018
Rodrigues, Juliana L.G. | Bandeira, Matheus J. | Araújo, Cecília F.S. | dos Santos, Nathália R. | Anjos, Ana Laura S. | Koin, Ng Lai | Pereira, Laiz C. | Oliveira, Sérgio S.P. | Mergler, Donna | Menezes-Filho, José A.
Previously, we showed that manganese (Mn) levels in settled dust in elementary schools increased at a rate of 34.1% per km closer to a ferro-manganese alloy plant in the rainy season. In this study, we investigated how this environmental pollution indicator varied in the dry season and if there was an association with Mn biomarker levels in school-aged children. Dust samples were collected with passive samplers (disposable Petri dishes) placed in interior and exterior environments of 14 elementary schools. Occipital hair, toenails and blood samples were collected from 173 students aged 7–12 years from three of these schools, with varying distance from the industrial plant. Mn and lead (Pb) levels were measured by graphite furnace atomic absorption spectrometry. Mn concentration geometric means (GM) in dust fall accumulation in interior environments of schools located at 2, 4, 6 and > 6 km-radii from the plant were 2212, 584, 625 and 224 μg Mn/m2/30 days, respectively. The modelled rate of change of dust Mn levels decreases by 59.8% for each km further from the plant. Pb levels in settled dust varied between 18 and 81 μg/m2/30 days with no association with distance from the plant. Blood lead levels median (range) were 1.2 μg/dL (0.2–15.6), of which 97.8% were <5 μg/dL. Mn in hair and toenails were 0.66 μg/g (0.16–8.79) and 0.86 μg/g (0.15–13.30), respectively. Mn loading rates were positively associated with log MnH (β = 1.42 × 10−5, p < 0.001) after adjusting for children's age; and also with log MnTn (β = 2.31 × 10−5, p < 0.001) independent of age. Mn loading rates explained 18.5% and 28.5% of the variance in MnH and MnTn levels, respectively. School-aged children exposure to Mn, independently of age, increases significantly with school proximity to the ferro-manganese alloy plant.
Mostrar más [+] Menos [-]Pet exposure in utero and postnatal decreases the effects of air pollutants on hypertension in children: A large population based cohort study
2018
Lawrence, Wayne R. | Yang, Mo | Lin, Shao | Wang, Si-Quan | Liu, Yimin | Ma, Huimin | Chen, Duo-Hong | Yang, Bo-Yi | Zeng, Xiao-Wen | Hu, Liwen | Dong, Guang-Hui
The effect of ambient air pollution exposure on childhood hypertension has emerged as a concern in China, and previous studies suggested pet ownership is associated with lower blood pressure (BP). However, limited information exists on the interactive effects pet ownership and air pollution exposure has on hypertension. We investigated the interactions between exposure to pet ownership and air pollutants on hypertension in Chinese children. 9354 students in twenty-four elementary and middle schools (aged 5–17 years) in Northeastern China were evaluated during 2012–2013. Four-year average concentrations of particulate matter with aerodynamic diameter of ≤10 μm (PM10), SO2, NO2, and O3, were collected in the 24 districts from 2009 to 2012. Hypertension was defined as average diastolic or systolic BP (three time measurements) in the 95th percentile or higher based on height, age, and sex. To examine effects, two-level regression analysis was used, controlling covariates. Consistent interactions between exposure to pet and air pollutants were observed. Compared to children exposed to pet, those not exposed exhibited consistently stronger effects of air pollution. The highest odds ratios (ORs) per 30.6 μg/m3 increase in PM10 were 1.79 (95%confidence interval [95%CI]: 1.29–2.50) in children without current pet exposure compared to 1.24 (95%CI: 0.85–1.82) in children with current pet exposure. As for BP, only O3 had an interaction for all exposure to pet ownership types, and showed lower BP in children exposed to pet. The increases in mean diastolic BP per 46.3 μg/m3 increase in O3 were 0.60 mmHg (95%CI: 0.21, 0.48) in children without pet exposure in utero compared with 0.34 mmHg (95%CI: 0.21, 0.48) in their counterparts. When stratified by age, pet exposure was more protective among younger children. In conclusion, in this large population-based cohort, pet ownership is associated with smaller associations between air pollution and hypertension in children, suggesting pet ownership reduces susceptibility to the health effects of pollutants.
Mostrar más [+] Menos [-]Integrating science education and marine conservation through collaborative partnerships
2015
Martin, Jeannie Miller | Higgins, Katie | Lee, Kristin | Stearns, Kira | Hunt, Lori
The Georgia Sea Turtle Center has a mission of conservation based rehabilitation, research, and education. Marine debris is a serious threat to marine species. In an effort to educate local students, the GSTC obtained a grant to provide educational opportunities to local third graders. Third and fourth grade classes in Glynn County, Georgia were offered a Garbage in the Water program and 964 students were reached. After programming, students showed a statistically significant (p<.0001) increase in test scores between the pre and posttests. This success led to repeat funding for additional programming for first grades as well as a formalized relationship with the Glynn County School District. As part of this relationship the Georgia Sea Turtle Center is now the official field trip location for all third grades in the district.
Mostrar más [+] Menos [-]Influence of indoor air quality on sleep quality of university students in Lisbon
2022
Ramos, João | Belo, Joana | Silva, Dario | Diogo, Carlos | Almeida, Susana Marta | Canha, Nuno
Sleep is a crucial aspect of the human daily life since it allows us to recover from physical and psychological fatigue and its lack can bring several consequences to human health. People spend around one third of their life sleeping but, despite that, their exposure to pollutants during sleep is often neglected. Specifically, students typically change their habits after entering university, due to the freedom that they are allowed at this stage of their lives. These habits often include their sleep patterns, which not only affects their health, but their academic performance as well. This study aimed to assess the indoor air quality (IAQ) that university students are exposed to in their sleeping environment and how it affects their sleep quality. Firstly, an online survey, based in standardized questionnaires, was conducted to a sample of 1040 individuals to characterize sleep habits and, ultimately, to provide an overview of the sleep quality of the Portuguese population. Students were one of the population groups that showed worse results: only 31% had good sleep quality and only 62% showed good sleep health. Afterwards, a study to assess sleep quality (by actigraphy and standardized questionnaires) and IAQ (by a monitoring unit based in low-cost sensors) during the sleeping period of two consecutive nights of 13 students in Lisbon university dorms was conducted. Mean levels of CO₂ and VOCs above the established legislation were found during sleep, indicating that ventilation conditions were not sufficient to keep an acceptable IAQ. Temperature was also out of the acceptable comfort range during 44% of the sleeping time. The perceived sleep quality of students was found to be negatively associated with the number of awakenings and the mean levels of carbon dioxide and relative humidity during the sleeping period. These results confirm previous findings where some IAQ parameters may influence the sleep quality of the individuals, highlighting the importance to focus on the IAQ of sleeping environments as a strategy to improve sleep quality of individuals.
Mostrar más [+] Menos [-]Can we enhance amphibians’ habitat restoration in the post-mining areas?
2016
Klimaszewski, Krzysztof | Pacholik, Ewa | Snopek, Adam
The study was aimed to evaluate the selected improvements of nature restoration in a depleted gravel pit. The study site consisted of four water reservoirs of different shapes and sizes, flooded after the gravel extraction ended. Ecological succession monitoring, conducted by the Warsaw University of Life Sciences students associated in the Student Scientific Association of Animal Sciences Faculty since the completion of mining, have focused on amphibians. A twofold approach upheld amphibian species population dynamics, as well as selected habitat elements. The restoration practices dedicated to habitat conditions enhancing have been proved to be definitely effective and useful for similar sites.
Mostrar más [+] Menos [-]Interactions between dietary habits and home environmental exposures on respiratory symptoms in Romanian school children: an analysis of data from the SINPHONIE project
2020
Lawrence, Wayne R. | Lin, Shao | Lin, Ziqiang | Gurram, Namratha | Neamtiu, Iulia A. | Csobod, Eva | Gurzau, Eugen
In this study, we investigated the interactions between household pollutants and dietary habits on children’s respiratory health. Our cross-sectional study collected self-reported information including health symptoms (allergy-like, asthma-like, and flu-like symptoms), home characteristics, dietary habits, and demographic information from questionnaires administered to parents of 280 school children in Romania. Unconditional logistic regression and stratified analyses were used to assess the interactions between dietary factors and environmental exposures on health symptoms among children, controlling for sociodemographic characteristics and co-exposures. We found that frequency of fruit consumption had significant interaction with residing near heavy traffic on allergy-like symptoms among children (p = 0.036). However, no association was observed by frequency of fruit consumption. Although no significant interaction was observed, we found that students with infrequent fruit consumption and residing near heavy traffic roads had elevated odds of asthma-like (POR 6.37; 95% CI 1.22, 33.29) and flu-like symptoms (POR 3.75; 95% CI 1.12, 11.86) than those who frequently consumed fruits. Likewise, low vegetable consumption was associated with increased asthma-like symptoms (POR 2.93; 95% CI 1.04, 8.24). Increased odds of asthma-like symptoms were observed among school children that resided near heavy traffic roads and frequently consumed milk (POR 2.80; 95% CI 1.24, 6.31) and yoghurt (POR 2.86; 95% CI 1.05, 7.75) compared to those that infrequently consumed dairy. Our findings suggest that frequent fruit and vegetable consumption may mitigate the negative effects of exposure to heavy traffic near dwelling on respiratory symptoms in Romanian children.
Mostrar más [+] Menos [-]Impact of urbanization factors on mortality due to unintentional injuries using panel data regression model and spatial-temporal analysis
2020
Pu, Haixia | Li, Bin | Luo, Dongqi | Wang, Shaobin | Wang, Zhaolin | Zhao, Wei | Zheng, Lingyu | Duan, Ping
Unintentional injuries pose a great risk for human health in China. Few studies have focused on unintentional injuries at national level from urbanization perspective. The panel data of mortality rate of transportation accidents (TA), fall and drowning and sinking (DS) is investigated, and urbanization development index is collected. Global Moran’s I and linear regression of panel data are applied to determine the spatial distribution and spatial influencing factors of unintentional injuries. The results are the following: (1) The unintentional injury such as TA, fall, and DS shows clear non-uniformity of spatial distribution and relative immobility through time. (2) A 10,000 tons increase in SO₂ emission amount (SO₂ EA) and emission of smoke and dust (ESD) can result in 15.7 and 12.5 increases in TA death in eastern region, respectively. Meanwhile, A 10,000 tons increase in NOₓ emission amount can cause 15.1 increase in TA death in western region. For every 100 billion yuan increase in GDP, the fall death can reduce by 8.4 in central region. One bed increase in number of hospital beds per 10,000 population (NHBP) is favorable for decreasing in fall death by 16.7 in eastern region. However, increase in number of workers enjoying industrial injury (NEWII) does not reduce the fall death in eastern region. (3) For every 1 ten thousand people increase in number of students in ordinary high schools (NSOHS) is conductive to reducing DS death by 7.8 in the western region. Our findings show that there exist spatial differences for urbanization influencing TA, fall, and DS death in eastern, western, and central regions. This study is expected to provide a reference for unintentional injuries control in those three regions.
Mostrar más [+] Menos [-]Decomposition of passive smoking inequality in Iranian children and adolescents: the CASPIAN-V Study
2019
Rarani, Mostafa Amini | Heshmat, Ramin | Djalalinia, Shirin | Motlagh, Mohammad Esmaeil | Ziaodini, Hasan | Mahdavi-Gorabi, Armita | Taheri, Majzoubeh | Ahadi, Zeinab | Qorbani, Mostafa | Kelishadi, Roya
To investigate the socioeconomic inequality in passive smoking in Iranian children and adolescents. Through a multistage random cluster sampling method, a representative sample of 14,400 school students, aged 6–18 years, were enrolled from urban and rural areas of 30 provinces of Iran. Using a non-linear principal component analysis (NLPCA), the correlated variables were summarized as socioeconomic status (SES). Normalized concentration index (NCI) was used to measure inequality in passive smoking at national and regional SES levels. We decomposed total socioeconomic inequality in passive smoking into explanatory variables to identify the main contributors of inequality in passive smoking in the population studied. Data of 12,327 students and parents were complete for the current study. The response rate was 85.6% (50.9% boys, 71.2% urban residents). About 44% of Iranian students were exposed to passive smoking. The NCI for passive smoking at a national level was − 0.043 (95% confidence interval − 0.035, − 0.012), indicating that passive smoking was more concentrated among poorer children and adolescents. This inequality was statistically significant at a national level and in all regions except for regions with lower middle- and lowest SES levels. Considering the decomposition analysis, the household SES (63%), mothers’ educational level (37%), fathers’ educational level (29%), and school type (18%) made the largest positive contribution to inequality in passive smoking of children and adolescents. Passive smoking was distributed unequally among Iranian children and adolescents; it was more concentrated among socioeconomically disadvantaged families. Public health policies attentions should be given to reduce passive smoking among low SES children and adolescents living with illiterate or low-educated parents.
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