The Experts below are selected from a list of 4512 Experts worldwide ranked by ideXlab platform
Deborah H Bennett - One of the best experts on this subject based on the ideXlab platform.
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ranking cancer risks of organic Hazardous Air Pollutants in the united states
Environmental Health Perspectives, 2007Co-Authors: Miranda Loh, Jonathan I Levy, John D Spengler, Andres E Houseman, Deborah H BennettAbstract:BackgroundIn this study we compared cancer risks from organic Hazardous Air Pollutants (HAPs) based on total personal exposure summed across different microenvironments and exposure pathways.Method...
L Sally J Liu - One of the best experts on this subject based on the ideXlab platform.
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spatial temporal and cancer risk assessment of selected Hazardous Air Pollutants in seattle
Environment International, 2011Co-Authors: Alison C Cullen, L Sally J Liu, Hal Westberg, John WilliamsonAbstract:In the Seattle Air Toxics Monitoring Pilot Program, we measured 15 Hazardous Air Pollutants (HAPs) at 6 sites for more than a year between 2000 and 2002. Spatial-temporal variations were evaluated with random-effects models and principal component analyses. The potential health risks were further estimated based on the monitored data, with the incorporation of the bootstrapping technique for the uncertainty analysis. It is found that the temporal variability was generally higher than the spatial variability for most Air toxics. The highest temporal variability was observed for tetrachloroethylene (70% temporal vs. 34% spatial variability). Nevertheless, most Air toxics still exhibited significant spatial variations, even after accounting for the temporal effects. These results suggest that it would require operating multiple Air toxics monitoring sites over a significant period of time with proper monitoring frequency to better evaluate population exposure to HAPs. The median values of the estimated inhalation cancer risks ranged between 4.3x10(-5) and 6.0x10(-5), with the 5th and 95th percentile levels exceeding the 1 in a million level. VOCs as a whole contributed over 80% of the risk among the HAPs measured and arsenic contributed most substantially to the overall risk associated with metals
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cancer risk assessment of selected Hazardous Air Pollutants in seattle
Environment International, 2009Co-Authors: Alison C Cullen, Timothy V Larson, John Williamson, L Sally J LiuAbstract:The risk estimates calculated from the conventional risk assessment method usually are compound specific and provide limited information for source-specific Air quality control. We used a risk apportionment approach, which is a combination of receptor modeling and risk assessment, to estimate source-specific lifetime excess cancer risks of selected Hazardous Air Pollutants. We analyzed the speciated PM(2.5) and VOCs data collected at the Beacon Hill in Seattle, WA between 2000 and 2004 with the Multilinear Engine to first quantify source contributions to the mixture of Hazardous Air Pollutants (HAPs) in terms of mass concentrations. The cancer risk from exposure to each source was then calculated as the sum of all available species' cancer risks in the source feature. We also adopted the bootstrapping technique for the uncertainty analysis. The results showed that the overall cancer risk was 6.09 x 10(-5), with the background (1.61 x 10(-5)), diesel (9.82 x 10(-6)) and wood burning (9.45 x 10(-6)) sources being the primary risk sources. The PM(2.5) mass concentration contributed 20% of the total risk. The 5th percentile of the risk estimates of all sources other than marine and soil were higher than 110(-6). It was also found that the diesel and wood burning sources presented similar cancer risks although the diesel exhaust contributed less to the PM(2.5) mass concentration than the wood burning. This highlights the additional value from such a risk apportionment approach that could be utilized for prioritizing control strategies to reduce the highest population health risks from exposure to HAPs
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source apportionment of pm2 5 and selected Hazardous Air Pollutants in seattle
Science of The Total Environment, 2007Co-Authors: Timothy V Larson, John Williamson, Hal Westberg, L Sally J LiuAbstract:The potential benefits of combining the speciated PM(2.5) and VOCs data in source apportionment analysis for identification of additional sources remain unclear. We analyzed the speciated PM(2.5) and VOCs data collected at the Beacon Hill in Seattle, WA between 2000 and 2004 with the Multilinear Engine (ME-2) to quantify source contributions to the mixture of Hazardous Air Pollutants (HAPs). We used the 'missing mass', defined as the concentration of the measured total particle mass minus the sum of all analyzed species, as an additional variable and implemented an auxiliary equation to constrain the sum of all species mass fractions to be 100%. Regardless of whether the above constraint was implemented and/or the additional VOCs data were included with the PM(2.5) data, the models identified that wood burning (24%-31%), secondary sulfate (20%-24%) and secondary nitrate (15%-20%) were the main contributors to PM(2.5). Using only PM(2.5) data, the model distinguished two diesel features with the 100% constraint, but identified only one diesel feature without the constraint. When both PM(2.5) and VOCs data were used, one additional feature was identified as the major contributor (26%) to total VOC mass. Adding VOCs data to the speciated PM(2.5) data in source apportionment modeling resulted in more accurate source contribution estimates for combustion related sources as evidenced by the less 'missing mass' percentage in PM(2.5). Using the source contribution estimates, we evaluated the validity of using black carbon (BC) as a surrogate for diesel exhaust. We found that BC measured with an aethalometer at 370 nm and 880 nm had reasonable correlations with the estimated concentrations of diesel particulate matters (r>0.7), as well as with the estimated concentrations of wood burning particles during the heating seasons (r=0.56-0.66). This indicates that the BC is not a unique tracer for either source. The difference in BC between 370 and 880 nm, however, correlated well exclusively with the estimated wood smoke source (r=0.59) and may be used to separate wood smoke from diesel exhaust. Thus, when multiple BC related sources exist in the same monitoring environment, additional data processing or modeling of the BC measurements is needed before these measurements could be used to represent the diesel exhaust.
William W Nazaroff - One of the best experts on this subject based on the ideXlab platform.
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inhalation of Hazardous Air Pollutants from environmental tobacco smoke in us residences
Journal of Exposure Science and Environmental Epidemiology, 2004Co-Authors: William W Nazaroff, Brett C SingerAbstract:In the United States, 48 million adults smoke 3.5–5 × 1011 cigarettes/year. Many cigarettes are smoked in private residences, causing regular environmental tobacco smoke (ETS) exposure to roughly 31 million nonsmokers (11% of the US population), including 16 million juveniles. (Upper bound estimates are 53 million exposed nonsmokers including 28 million juveniles.) ETS contains many chemical species whose industrial emissions are regulated by the US federal government as Hazardous Air Pollutants (HAPs). In this paper, average daily residential exposures to and intakes of 16 HAPs in ETS are estimated for US nonsmokers who live with smokers. The evaluation is based on material-balance modeling; utilizes published data on smoking habits, demographics, and housing; and incorporates newly reported exposure-relevant emission factors. The ratio of estimated average exposure concentrations to reference concentrations is close to or greater than one for acrolein, acetaldehyde, 1,3-butadiene, and formaldehyde, indicating potential for concern regarding noncancer health effects from chronic exposures. In addition, lifetime cancer risks from residential ETS exposure are estimated to be substantial (∼2–500 per million) for each of five known or probable human carcinogens: acetaldehyde, formaldehyde, benzene, acrylonitrile, and 1,3-butadiene. Cumulative population intakes from residential ETS are compared for six key compounds against ambient sources of exposure. ETS is found to be a dominant source of environmental inhalation intake for acrylonitrile and 1,3-butadiene. It is an important cause of intake for acetaldehyde, acrolein, and formaldehyde, and a significant contributor to intake for benzene.
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inhalation of Hazardous Air Pollutants from environmental tobacco smoke in us residences
Journal of Exposure Science and Environmental Epidemiology, 2004Co-Authors: William W Nazaroff, Brett C SingerAbstract:In the United States, 48 million adults smoke 3.5-5 x 10(11) cigarettes/year. Many cigarettes are smoked in private residences, causing regular environmental tobacco smoke (ETS) exposure to roughly 31 million nonsmokers (11% of the US population), including 16 million juveniles. (Upper bound estimates are 53 million exposed nonsmokers including 28 million juveniles.) ETS contains many chemical species whose industrial emissions are regulated by the US federal government as Hazardous Air Pollutants (HAPs). In this paper, average daily residential exposures to and intakes of 16 HAPs in ETS are estimated for US nonsmokers who live with smokers. The evaluation is based on material-balance modeling; utilizes published data on smoking habits, demographics, and housing; and incorporates newly reported exposure-relevant emission factors. The ratio of estimated average exposure concentrations to reference concentrations is close to or greater than one for acrolein, acetaldehyde, 1,3-butadiene, and formaldehyde, indicating potential for concern regarding noncancer health effects from chronic exposures. In addition, lifetime cancer risks from residential ETS exposure are estimated to be substantial ( approximately 2-500 per million) for each of five known or probable human carcinogens: acetaldehyde, formaldehyde, benzene, acrylonitrile, and 1,3-butadiene. Cumulative population intakes from residential ETS are compared for six key compounds against ambient sources of exposure. ETS is found to be a dominant source of environmental inhalation intake for acrylonitrile and 1,3-butadiene. It is an important cause of intake for acetaldehyde, acrolein, and formaldehyde, and a significant contributor to intake for benzene.
Miranda Loh - One of the best experts on this subject based on the ideXlab platform.
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ranking cancer risks of organic Hazardous Air Pollutants in the united states
Environmental Health Perspectives, 2007Co-Authors: Miranda Loh, Jonathan I Levy, John D Spengler, Andres E Houseman, Deborah H BennettAbstract:BackgroundIn this study we compared cancer risks from organic Hazardous Air Pollutants (HAPs) based on total personal exposure summed across different microenvironments and exposure pathways.Method...
He-zhong Tian - One of the best experts on this subject based on the ideXlab platform.
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atmospheric emission inventory of Hazardous Air Pollutants from biomass direct fired power plants in china historical trends spatial variation characteristics and future perspectives
Science of The Total Environment, 2021Co-Authors: Shumin Lin, He-zhong Tian, Yan Hao, Shuhan Liu, Lining Luo, Xiaoxuan Bai, Wei Liu, Shuang Zhao, Jiming Hao, Zhihui GuoAbstract:Abstract The agricultural and forestry biomass direct-fired power generation represents an important technology to promote the low-carbon energy transition and agricultural waste reuse in China. In recent years, emissions of Hazardous Air Pollutants (HAPs) caused by the rapid biomass industrialization have attracted increasing attention. To investigate the characteristics of HAPs emitted from biomass power plants in China, a multiple-year comprehensive emission inventory including NOx, SO2, PM, PM10, PM2.5, and trace elements (As, Cd, Cr, Cu, Hg, Pb, Zn) has been established for the period of 2006–2017. As a result of the emission standard (GB13223-2011), emissions of conventional HAPs have declined since 2014. The results show that national total emissions in 2017 were estimated at 29,516.0 t of NOx, 14,192.1 t of SO2, 4100.7 t of PM, 2353.9 t of PM10, 1630.6 t of PM2.5, 3057.2 kg of As, 1622.8 kg of Cd, 8285.8 kg of Cr, 54,443.4 kg of Cu, 132.9 kg of Hg, 66,325.8 kg of Pb, and 175,587.9 kg of Zn, respectively. The majority of HAPs emissions have been concentrated in eastern, northeastern, and central areas of mainland China. Shandong, Heilongjiang, and Anhui represent the top three provinces with the highest HAPs emissions from 2012 to 2017. Besides, the future emissions in 2025 and 2035 under the ultra-low emission policy are predicted with scenario analysis.
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historical and future emission of Hazardous Air Pollutants haps from gas fired combustion in beijing china
Environmental Science and Pollution Research, 2017Co-Authors: Yifeng Xue, He-zhong Tian, Lei Nie, Zhen Zhou, Jing Yan, Linglong ChengAbstract:The consumption of natural gas in Beijing has increased in the past decade due to energy structure adjustments and Air pollution abatement. In this study, an integrated emission inventory of Hazardous Air Pollutants (HAPs) emitted from gas-fired combustion in Beijing was developed for the period from 2000 to 2014 using a technology-based approach. Future emission trends were projected through 2030 based on current energy-related and emission control policies. We found that emissions of primary HAPs exhibited an increasing trend with the rapid increase in natural gas consumption. Our estimates indicated that the total emissions of NO X , particulate matter (PM)10, PM2.5, CO, VOCs, SO2, black carbon, Pb, Cd, Hg, As, Cr, Cu, Ni, Zn, polychlorinated dibenzo-p-dioxins and dibenzofurans, and benzo[a]pyrene from gas-fired combustion in Beijing were approximately 22,422 t, 1042 t, 781 t, 19,097 t, 653 t, 82 t, 19 t, 0.6 kg, 0.1 kg, 43 kg, 52 kg, 0.3 kg, 0.03 kg, 4.3 kg, 0.6 kg, 216 μg, and 242 g, respectively, in 2014. To mitigate the associated Air pollution and health risks caused by gas-fired combustion, stricter emission standards must be established. Additionally, combustion optimization and flue gas purification system could be used for lowering NO X emissions from gas-fired combustion, and gas-fired facilities should be continuously monitored based on emission limits.
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atmospheric emission inventory of Hazardous Air Pollutants from china s cement plants temporal trends spatial variation characteristics and scenario projections
Atmospheric Environment, 2016Co-Authors: Shenbing Hua, He-zhong Tian, Chuanyong Zhu, Jiajia Gao, Kun Wang, Yifeng Xue, Yong Wang, Shiheng Duan, Junrui ZhouAbstract:Abstracts A multiple-year comprehensive emission inventory of typical Hazardous Air Pollutants (HAPs) from China's cement industry for the period 1980–2012, has been established by using technology-based dynamic emission factors and detailed annual plant-specific cement production from different types of kilns. Our results show that the total emissions of various HAPs (SO 2 , NO X , CO, PM, Hg, Cd, Cr, Pb, Zn, As, Ni and Cu) have rapidly increased by about 1–21 times at an annual average growth rate of 1–10% over the past three decades. Remarkably uneven spatial allocation features of these Pollutants among provinces are observed. HAPs emissions are primarily concentrated in the eastern and coastal provinces due to the concentration of cement plants and their huge volume of coal consumption. We predict the future emission trends of HAPs through 2050 based on industry construction and policy guidance, and our scenario analysis indicates that HAPs emissions will drop substantially because of the combined effects of cement production yields reduction and the increasing application rate of various Air pollution control devices. The study suggests that highlighted attention should be paid to this energy-intensive industry to ensure stricter emission standards are implemented for these HAPs emissions in the future.
