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Linking the environmental loads to the fate of PPCPs in Beijing: Considering both the treated and untreated wastewater sources
2015
Wang, Bin | Dai, Guohua | Deng, Shubo | Huang, Jun | Wang, Yujue | Yu, Gang
The environmental loads of pharmaceutical and personal care products (PPCPs) in Beijing were estimated from direct discharge of untreated wastewater and WWTP treated effluent. The annual environmental loads of 15 PPCP components ranged from 16.3 kg (propranolol) to 9.85 tons (caffeine). A fugacity model was developed to successfully estimate the PPCP pollution based on the estimated environmental load. The modeled results approximated the observed PPCP concentrations in Beijing. The untreated wastewater contributed significantly to PPCP pollution in Beijing, ranging from 46% (propranolol) to 99% (caffeine). The total environmental burden of target PPCPs ranged from 0.90 kg (propranolol) to 536 kg (caffeine). Water is the most important media for the fate of PPCPs. Monte Carlo-based concentration distributions of PPCPs are consistent with the observed results. The most important way to reduce the PPCP pollution is to both improve wastewater collection rate and adopt deep treatment technologies.
Afficher plus [+] Moins [-]Adsorption of perfluoroalkyl acids by carbonaceous adsorbents: Effect of carbon surface chemistry
2015
Zhi, Yue | Liu, Jinxia
Adsorption by carbonaceous sorbents is among the most feasible processes to remove perfluorooctane sulfonic (PFOS) and carboxylic acids (PFOA) from drinking and ground waters. However, carbon surface chemistry, which has long been recognized essential for dictating performance of such sorbents, has never been considered for PFOS and PFOA adsorption. Thus, the role of surface chemistry was systematically investigated using sorbents with a wide range in precursor material, pore structure, and surface chemistry. Sorbent surface chemistry overwhelmed physical properties in controlling the extent of uptake. The adsorption affinity was positively correlated carbon surface basicity, suggesting that high acid neutralizing or anion exchange capacity was critical for substantial uptake of PFOS and PFOA. Carbon polarity or hydrophobicity had insignificant impact on the extent of adsorption. Synthetic polymer-based Ambersorb and activated carbon fibers were more effective than activated carbon made of natural materials in removing PFOS and PFOA from aqueous solutions.
Afficher plus [+] Moins [-]A statistical model for determining impact of wildland fires on Particulate Matter (PM2.5) in Central California aided by satellite imagery of smoke
2015
Preisler, Haiganoush K. | Schweizer, Donald | Cisneros, Ricardo | Procter, Trent | Ruminski, Mark | Tarnay, Leland
As the climate in California warms and wildfires become larger and more severe, satellite-based observational tools are frequently used for studying impact of those fires on air quality. However little objective work has been done to quantify the skill these satellite observations of smoke plumes have in predicting impacts to PM2.5 concentrations at ground level monitors, especially those monitors used to determine attainment values for air quality under the Clean Air Act. Using PM2.5 monitoring data from a suite of monitors throughout the Central California area, we found a significant, but weak relationship between satellite-observed smoke plumes and PM2.5 concentrations measured at the surface. However, when combined with an autoregressive statistical model that uses weather and seasonal factors to identify thresholds for flagging unusual events at these sites, we found that the presence of smoke plumes could reliably identify periods of wildfire influence with 95% accuracy.
Afficher plus [+] Moins [-]Tracing mercury pathways in Augusta Bay (southern Italy) by total concentration and isotope determination
2015
Bonsignore, M. | Tamburrino, S. | Oliveri, E. | Marchetti, A. | Durante, C. | Berni, A. | Quinci, E. | Sprovieri, M.
The mercury (Hg) pollution of sediments is the main carrier of Hg for the biota and, subsequently, for the local fish consumers in Augusta Bay area (SE Sicily, Italy), a coastal marine system affected by relevant sewage from an important chlor-alkali factory. This relationship was revealed by the determination of Mass Dependent (MDF) and Mass Independent Fractionation (MIF) of Hg isotopes in sediment, fish and human hair samples. Sediments showed MDF but no MIF, while fish showed MIF, possibly due to photochemical reduction in the water column and depending on the feeding habitat of the species. Benthic and demersal fish exhibited MDF similar to that of sediments in which anthropogenic Hg was deposited, while pelagic organisms evidenced higher MDF and MIF due to photoreduction. Human hair showed high values of δ202Hg (offset of +2.2‰ with respect to the consumed fish) and Δ199Hg, both associated to fish consumption.
Afficher plus [+] Moins [-]Characterisation of particulate matter on airborne pollen grains
2015
Ribeiro, Helena | Guimarães, Fernanda | Duque, Laura | Noronha, Fernando | Abreu, Ilda
A characterization of the physical–chemical composition of the atmospheric PM adsorbed to airborne pollen was performed. Airborne pollen was sampled using a Hirst-type volumetric spore sampler and observed using a Field Emission Electron Probe Microanalyser for PM analysis. A secondary electron image was taken of each pollen grain and EDS spectra were obtained for individually adsorbed particles. All images were analysed and the size parameters of the particles adsorbed to pollen was determined. The measured particles’ equivalent diameter varied between 0.1 and 25.8 μm, mostly in the fine fraction. The dominant particulates identified were Si-rich, Organic-rich, SO-rich, Metals & Oxides and Cl-rich. Significant daily differences were observed in the physical–chemical characteristics of particles adsorbed to the airborne pollen wall. These differences were correlated with weather parameters and atmospheric PM concentration. Airborne pollen has the ability to adsorb fine particles that may enhance its allergenicity.
Afficher plus [+] Moins [-]Estimating evaporative vapor generation from automobiles based on parking activities
2015
Dong, Xinyi | Tschantz, Michael | Fu, Joshua S.
A new approach is proposed to quantify the evaporative vapor generation based on real parking activity data. As compared to the existing methods, two improvements are applied in this new approach to reduce the uncertainties: First, evaporative vapor generation from diurnal parking events is usually calculated based on estimated average parking duration for the whole fleet, while in this study, vapor generation rate is calculated based on parking activities distribution. Second, rather than using the daily temperature gradient, this study uses hourly temperature observations to derive the hourly incremental vapor generation rates. The parking distribution and hourly incremental vapor generation rates are then adopted with Wade–Reddy's equation to estimate the weighted average evaporative generation. We find that hourly incremental rates can better describe the temporal variations of vapor generation, and the weighted vapor generation rate is 5–8% less than calculation without considering parking activity.
Afficher plus [+] Moins [-]Medication type modifies inflammatory response to traffic exposure in a population with type 2 diabetes
2015
Rioux, Christine L. | Tucker, Katherine L. | Brugge, Doug | Mwamburi, Mkaya
The association between residential traffic exposure and change in C-reactive protein over 2-years was evaluated using multivariate linear regression including interaction models for traffic and diabetes medication use/type (insulin vs. oral hypoglycemic agents (OHAs)).The study population was Puerto Rican adults (n = 356) residing in greater Boston with type 2 diabetes. Traffic was characterized as proximity to roads with >20,000 weekday traffic volumes, and multi-directional traffic density.Increases in CRP concentration were significantly associated with residence ≤100 m of a roadway (p = 0.009) or near multiple roadways (p < 0.001), vs. further away, for individuals using insulin in stratified models, with consistent results in interaction models (p = 0.071 and p = 0.002). CRP was significantly lower with highest traffic density exposure in stratified (p = 0.03) and interaction models (p = 0.024) for individuals using OHAs.Individuals on insulin experienced increased CRP concentrations with traffic exposure over a 2-year study period, while those using OHAs did not experience increases.
Afficher plus [+] Moins [-]New observations on PAH pollution in old heavy industry cities in northeastern China
2015
Song, Ningning | Ma, Junhua | Yu, Yang | Yang, Zhifeng | Li, Yingxia
This study investigated the distinctive PAHs adsorbed on street dust near various industries in the three typical industrialized cities of Daqing (DQ), Harbin (HEB) and Jilin (JL) in northeastern China. The mean ∑PAHs concentrations in street dust of DQ, HEB and JL were 1.84, 4.87, 12.38 μg/g, respectively. Typical petroleum resource city DQ had higher proportions of low and medium ringed PAHs with higher proportions of phenanthrene (Phe), naphthalene (Nap), fluoranthene (Flua) and chrysene (Chr) at industrial sites. Typical chemical processing city JL had higher proportions of medium and high ringed PAHs with higher proportions of Flua, benz[a]anthracene (BaA), pyrene (Pyr) and benzo[a]pyrene (BaP) at industrial sites. Phe, Flua, Pyr and Chr were four major PAHs from most studied industries. The distinctive PAH emissions from the ferroalloy plant were BaA and BaP. BaA and BaP concentrations decreased by 90% at sites more than 2 km away from the ferroalloy plant.
Afficher plus [+] Moins [-]Air pollution and mortality: Effect modification by personal characteristics and specific cause of death in a case-only study
2015
Qiu, Hong | Tian, Linwei | Ho, Kin-fai | Pun, Vivian C. | Wang, Xiaorong | Yu, Ignatius T.S.
Short-term effects of air pollution on mortality have been well documented in the literature worldwide. Less is known about which subpopulations are more vulnerable to air pollution. We conducted a case-only study in Hong Kong to examine the potential effect modification by personal characteristics and specific causes of death. Individual information of 402,184 deaths of non-external causes and daily mean concentrations of air pollution were collected from 2001 to 2011. For a 10 μg/m3 increase of pollution concentration, people aged ≥∇65 years (compared with younger ages) had a 0.9–1.8% additional increase in mortality related to PM, NO2, and SO2. People dying from cardiorespiratory diseases (compared with other non-external causes) had a 1.6–2.3% additional increase in PM and NO2 related mortality. Other subgroups that were particularly susceptible were females and those economically inactive. Lower socioeconomic status and causes of cardiorespiratory diseases would increase the likelihood of death associated with air pollution.
Afficher plus [+] Moins [-]Pesticide leaching through sandy and loamy fields – Long-term lessons learnt from the Danish Pesticide Leaching Assessment Programme
2015
Rosenbom, Annette E. | Olsen, Preben | Plauborg, Finn | Grant, Ruth | Juhler, René K. | Brüsch, Walter | Kjær, Jeanne
The European Union authorization procedure for pesticides includes an assessment of the leaching risk posed by pesticides and their degradation products (DP) with the aim of avoiding any unacceptable influence on groundwater. Twelve-year's results of the Danish Pesticide Leaching Assessment Programme reveal shortcomings to the procedure by having assessed leaching into groundwater of 43 pesticides applied in accordance with current regulations on agricultural fields, and 47 of their DP. Three types of leaching scenario were not fully captured by the procedure: long-term leaching of DP of pesticides applied on potato crops cultivated in sand, leaching of strongly sorbing pesticides after autumn application on loam, and leaching of various pesticides and their DP following early summer application on loam. Rapid preferential transport that bypasses the retardation of the plow layer primarily in autumn, but also during early summer, seems to dominate leaching in a number of those scenarios.
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