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Indoor environmental quality in chemistry and chemical engineering laboratories at Izmir Institute of Technology
2015
Indoor air pollution in university research laboratories may be important to building occupants, especially for those who work in the laboratories. In this study, indoor air quality (IAQ) and indoor environmental comfort were investigated in research laboratories of two departments at a university. PM2.5, PM10, TVOC (total volatile organic compounds), and CO concentrations, and three comfort variables which are temperature, relative humidity, and CO2 were measured. PM2.5 concentration was determined gravimetrically by collecting particles on glass fiber filters, whereas the remaining pollutants and comfort variables were measured using a monitoring device. IAQ measurements showed that levels of all pollutants were under the limits in both of the departments except for TVOC in one laboratory which had a mean concentration of 182ppb. The comfort variables were in the comfort ranges for laboratories in both of the departments except for temperature in one laboratory with a mean value of 30 °C. In conclusion, measures are needed for extensive uses of organic solvents because ventilation may not be sufficient to keep VOC concentrations within the limits, and to provide thermal comfort.
Show more [+] Less [-]A review of standards and guidelines set by international bodies for the parameters of indoor air quality
2015
Abdul–Wahab, Sabah Ahmed | Chin Fah En, Stephen | Elkamel, Ali | Ahmadi, Lena | Yetilmezsoy, Kaan
Standards and guidelines as defined by various international agencies are employed by the researchers to evaluate an acceptable quality of air in indoor as well as outdoor environments. The main objective of this paper is to establish a comprehensive review of Indoor Air Quality (IAQ) guidelines and other standard values that are implemented currently. For this purpose, the present study summarizes the main standards and guidelines related to key indoor air pollutants and levels of thermal comfort developed by different agencies around the world. These agencies and organizations include the American Society of Heating, Refrigerating and Air– Conditioning Engineers (ASHRAE), the Hong Kong Environmental Protection Department (HKEPD), the World Health Organization (WHO), and the National Health and Medical Research Council (NHMRC) of Australia. Common indoor air pollutants that are found to frequently affect indoor populations are, carbon dioxide (CO2), nitrogen dioxide (NO2), formaldehyde (HCHO), carbon monoxide (CO), sulfur dioxide (SO2), and particulate matter in sizes <2.5 and 10 μm (PM2.5 and PM10, respectively). Other factors that affect IAQ are the moisture content of the air (i.e., relative humidity), the temperature of the indoor air, and the air speed or movement. Sick building syndrome (SBS) describes the various interactions between these major pollutants and factors of IAQ that cause adverse health effects on humans. In addition, this paper reviews various stipulated guidelines that are implemented by the relevant regulatory institutions and agencies to prevent SBS.
Show more [+] Less [-]Temporal and spatial distribution of tropospheric NO2 over Northeast Asia using OMI data during the years 2005–2010
2015
Kim, Deok–Rae | Lee, Jae–Bum | Keun Song, Chang | Kim, Seung–Yeon | Ma, Young–ll | Lee, Kyung–Mi | Cha, Jun–Seok | Lee, Sang–Deok
This study aimed to examine the main characteristics of tropospheric nitrogen dioxide (NO2) concentrations over the Northeast Asia, using the Ozone Monitoring Instrument (OMI) data from 2005 to 2010. The annual mean NO2 concentrations (AMNC) had an increasing trend mainly due to increasing NO2 emissions in China except during the 2008 Beijing Olympic Games period, while the reduction policies of South Korea and Japan have led it to be stagnant or decreased. To investigate further regional characteristics of NO2 increasing trends in China, we divided our study area into 6 geographical regions (sectors 1–6) and then considering 4 different socio–economic levels (groups 1–4) among main cities in Eastern regions (sector 2 and 4) where the concentrations level is the highest in China and NO2 concentrations show continued increasing trend. Especially OMI NO2 and emissions consistently showed that metropolitan/big—sized and developed cities (group 1), such as Beijing and Shanghai, had an increasing trend of NO2 concentrations until 2007 and decreasing thereafter, while small/mid–sized and developing cities (groups 2 and 3) kept a continuous increasing trend over all periods. The seasonal change in NO2 concentrations showed the apparent increasing trend in winter and no significant trend in summer in all groups except for group 1. These results indicate that an increase in AMNC in Northeast Asia was mainly attributed to the increasing NO2 concentrations in winter in groups 2 and 3. Therefore, it strongly suggests the importance of the NO2 management for groups 2 and 3 to improve air quality in the Northeast Asia.
Show more [+] Less [-]Human impact on atmospheric precipitation in a protected area in Western Poland. Results of long–term observations: Concentrations, deposition and trends
2015
Walna, Barbara
The paper presents the results of long–term measurements of rain chemistry in the woodland area of the Wielkopolski National Park (Western Poland) experiencing some human impact. The ions predominating in precipitation turned out to be those of ammonium and sulfates, which is indicative of human impact related with agriculture and animal breeding as well as with SO2 emissions. In the period 2002–2013 it is possible to identify, for both precipitation and throughfall, statistically significant decreasing trends in the concentrations and deposition of sulfates, ammonium and potassium, and an increasing trend for fluoride. Both bulk deposition and throughfall of N was higher than that of S. The deposition of nitrogen with throughfall was near to the critical load. High levels of acid–forming ions were observed in both, the winter and late–spring seasons, which proves not only the impact of heating but also of the local industry. Notable is the simultaneous occurrence of extremely high levels of acid–forming ions in some precipitation events, which might have many important implications for the soil, water and biota. There was a change in the pattern of atmospheric chemistry observed as a statistically significant downward trend in the rates of ionic concentration equivalents.
Show more [+] Less [-]Evaluation of the relationship between allergic diseases in school children at Seoul's roadside elementary schools and air pollution
2015
Lee, Chungsoo | Kim, Hohyun | Lim, Youngwook | Yang, Jiyeon | Yu, Seungdo | Lee, Jungsub | Chang, Junyoung | Son, Hyerim | Park, Jungwon | Shin, Dongchun
An elementary school is an important public place for children and it is where they spend most of their days. The objective of this study was to survey the environmental conditions at schools and to assess the relationship between air pollution and allergic diseases using the International Study of Asthma and Allergies in Childhood questionnaire. Nine elementary schools were selected and subsequently classified into three groups. The selection included two schools with no traffic-related or other pollutants, four schools situated near roads with six lanes, and three schools situated near beltways. Allergic diseases were assessed in a total of 6301 students. School zones with critical exposure to pollutants were selected within each school and were evaluated based on the levels of particulate matter, fine particulate matter, ozone, carbon monoxide, carbon dioxide, nitrogen dioxide, sulfur dioxide and black carbon. O3 and PM10 exposures were significantly associated with the prevalence of lifetime symptoms and diagnosis of asthma. O3 and PM10 exposures were also associated with lifetime symptoms, diagnosis, and 1-year physician diagnosis prevalence of allergic rhinitis. BC exposure was significantly associated with the rates of 1-year treatment of disease for allergic rhinitis. For schools located near sources of air pollution, the prevalence of lifetime symptoms for atopic dermatitis was significantly increased. Some symptoms of allergies were significantly increased at schools surrounded by a higher traffic volume. This study provides additional evidence that exposure to school zone air pollutants and traffic volume put school children at risk for childhood allergic diseases. Thus, strategies and actions are necessary to protect children in schools from exposure to environmental pollutants. In addition, future analysis to evaluate the relationship between traffic-related air pollution and the development of allergic diseases at more advanced ages are needed to confirm or refute these associations.
Show more [+] Less [-]Diesel particulate matter and coal dust from trains in the Columbia River Gorge, Washington State, USA
2015
Jaffé, Daniel | Putz, Justin | Hof, Greg | Hof, Gordon | Hee, Jonathan | Lommers-Johnson, Dee Ann | Gabela, Francisco | Fry, Juliane L. | Ayres, Benjamin | Kelp, Makoto | Minsk, Madison
We examined the emissions of diesel particulate matter (DPM) and coal dust from trains in the Columbia River Gorge (CRG) in Washington State by measuring PM1, PM2.5, CO2, and black carbon (BC) during the summer of 2014. We also used video cameras to identify the train type and speed.During the two-month period, we identified 293 freight trains and 74 coal trains that gave a PM2.5 enhancement of more than 3.0 μg/m3. We found an average PM2.5 enhancements of 8.8 and 16.7 μg/m3, respectively, for freight and coal trains. For most freight trains (52%), and a smaller fraction of coal trains (11%), we found a good correlation between PM2.5 and CO2. Using this correlation, we calculated a mean DPM emission factor (EF) of 1.2 gm/kg fuel consumed, with an uncertainty of 20%.For four coal trains, the videos revealed large plumes of coal dust emanating from the uncovered coal cars. These trains also had the highest peak PM2.5 concentrations recorded during our study (53–232 μg/m3). Trains with visible coal dust were observed for 5.4% of all coal trains, but 10.3% when the effective wind speed was greater than 90 km/h. We also found that nearly all coal trains emit coal dust based on (1) statistically higher PM2.5 enhancements from coal trains compared to freight trains; (2) the fact that most coal trains showed a weak correlation between PM2.5 and CO2, whereas most freight trains showed a strong relationship; (3) a statistically lower BC/PM2.5 enhancement ratio for coal trains compared to freight trains; and (4) a statistically lower PM1/PM2.5 enhancement ratio for coal trains compared to freight trains. Our results demonstrate that, on average, passage of a diesel powered open-top coal train result in nearly twice as much respirable PM2.5 compared to passage of a diesel-powered freight train.
Show more [+] Less [-]Clam predator protection is effective and necessary for food production
2015
Shellfish aquaculture is a widely practiced way of producing food for human consumption in coastal areas. When farming intertidal clams, farmers commonly protect young seedling clams from predatory losses by covering farmed plots with netting or screening. Recent discussion of the effectiveness of protective nets or screens and their environmental effects has raised questions concerning the utility of the practice. We provide data based on a review of more than 35 peer-reviewed articles, as well as our own research that demonstrates the efficacy of predator protection for clam farms in various habitats around the world. In addition, we evaluate the effects of screening on temperature, and comment on ancient practices of clam gardening as conducted in the Pacific Northwest.
Show more [+] Less [-]Marine debris ingestion by albatrosses in the southwest Atlantic Ocean
2015
Jiménez, Sebastián | Domingo, Andrés | Brazeiro, Alejandro | Defeo, Omar | Phillips, Richard A.
Plastics and other marine debris affect wildlife through entanglement and by ingestion. We assessed the ingestion of marine debris by seven albatross species in the southwest Atlantic by analyzing stomach contents of birds killed in fisheries. Of the 128 specimens examined, including four Diomedea species (n=78) and three Thalassarche species (n=50), 21 (16.4%) contained 1–4 debris items, mainly in the ventriculus. The most common type was plastic fragments. Debris was most frequent in Diomedea species (25.6%) and, particularly, Diomedea sanfordi (38.9%) and very rare in Thalassarche species (2.0%), presumably reflecting differences in foraging behavior or distribution. Frequency of occurrence was significantly higher in male than female Diomedea albatrosses (39.3% vs. 18.0%). Although levels of accumulated debris were relatively low overall, and unlikely to result in gut blockage, associated toxins might nevertheless represent a health risk for Diomedea albatrosses, compounding the negative impact of other human activities on these threatened species.
Show more [+] Less [-]Drivers and annual estimates of marine wildlife entanglement rates: A long-term case study with Australian fur seals
2015
McIntosh, Rebecca R. | Kirkwood, Roger | Sutherland, Duncan R. | Dann, Peter
Methods of calculating wildlife entanglement rates are not standardised between studies and often ignore the influence of observer effort, confounding comparisons. From 1997–2013 we identified 359 entangled Australian fur seals at Seal Rocks, south-eastern Australia. Most entanglement materials originated from commercial fisheries; most frequently entangling pups and juveniles. Using Generalized Additive Mixed Models, which incorporated observer effort and survey frequency, we identified that entanglements were observed more frequently amongst pups from July to October as they approached weaning. Neither the decline in regional fishing intensity nor changing seal population size influenced the incidence of entanglements. Using the models, we estimated that 302 (95% CI=182–510) entangled seals were at Seal Rocks each year, equivalent to 1.0% (CI=0.6–1.7%) of the site population. This study highlights the influence of observer effort and the value of long-term datasets for determining the drivers of marine debris entanglements.
Show more [+] Less [-]Sample port design for ballast water sampling: Refinement of guidance regarding the isokinetic diameter
2015
Wier, Timothy P. | Moser, Cameron S. | Grant, Jonathan F. | First, Matthew R. | Riley, Scott C. | Robbins-Wamsley, Stephanie H. | Drake, Lisa A.
By using an appropriate in-line sampling system, it is possible to obtain representative samples of ballast water from the main ballast line. An important parameter of the sampling port is its “isokinetic diameter” (DISO), which is the diameter calculated to determine the velocity of water in the sample port relative to the velocity of the water in the main ballast line. The guidance in the U.S. Environmental Technology Verification (ETV) program protocol suggests increasing the diameter from 1.0× DISO (in which velocity in the sample port is equivalent to velocity in the main line) to 1.5–2.0× DISO. In this manner, flow velocity is slowed—and mortality of organisms is theoretically minimized—as water enters the sample port. This report describes field and laboratory trials, as well as computational fluid dynamics modeling, to refine this guidance. From this work, a DISO of 1.0–2.0× (smaller diameter sample ports) is recommended.
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