Crop residue open burning is an important emission source of ambient particles in China.This study analyzed the particle emission characteristics of crop residue open burning through combustion experiments with a nove...Crop residue open burning is an important emission source of ambient particles in China.This study analyzed the particle emission characteristics of crop residue open burning through combustion experiments with a novel open combustion simulation device using three typical crop straws in north China(corn,wheat,and rice).Particle samples size ranging from 0.006–9.890μm were collected by an Electrical Low Pressure Impactor plus,a high size-resolution instrument capable of dividing particles into 14 size stages.The size distributions of organic carbon(OC),elemental carbon(EC),water-soluble ions,and elements were analyzed,and source chemical profiles were constructed for PM0.1,PM1,PM2.5,and PM10.The number concentration of particles was concentrated in the Aiken nuclei mode(0.006–0.054μm),accounting for 75%of the total number,whereas the mass concentration was concentrated in the accumulation mode(0.054–0.949μm),accounting for 85.43%of the mass loading.OC,EC,Cl−,and K(include total K and water-soluble K)were the major chemical components of the particles,whose mass percentage distributions differed from those of other components.These fivemain components exhibited a bell-shaped size distribution in the 0.006–9.890μm range,whereas the other components exhibited a U-shaped distribution.Among the chemical profiles for PM0.1–PM10,OC was the most important component at 10–30%,followed by EC at 2%–8%.The proportions of K^(+),Cl^(−),and K varied substantially in different experimental groups,ranging from 0–15%,and K+and Cl−were significantly correlated(r=0.878,α=0.000).展开更多
With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high sp...With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high spatial resolution of 0.25°× 0.25° and a temporal resolution of1 month was established based on the moderate resolution imaging spectroradiometer（MODIS） Thermal Anomalies/Fire Daily Level3 Global Product（MOD/MYD14A1）. Agriculture mechanization ratios and regional crop-specific grain-to-straw ratios were introduced to improve the accuracy of related activity data. Locally observed emission factors were used to calculate the primary pollutant emissions. MODIS satellite data were modified by combining them with county-level agricultural statistical data, which reduced the influence of missing fire counts caused by their small size and cloud cover. The annual emissions of CO2, CO, CH4,nonmethane volatile organic compounds（NMVOCs）, N2O, NOx, NH3, SO2, fine particles（PM2.5）,organic carbon（OC）, and black carbon（BC） were 150.40, 6.70, 0.51, 0.88, 0.01, 0.13, 0.07, 0.43,1.09, 0.34, and 0.06 Tg, respectively, in 2012. Crop residue open burning emissions displayed typical seasonal and spatial variation. The highest emission regions were the Yellow-Huai River and Yangtse-Huai River areas, and the monthly emissions were highest in June（37%）.Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of within ±126% for N2O to a high of within ± 169% for NH3.展开更多
Open burning of municipal solid waste(MSW)is a common practice in Nigeria.Emission of compounds of polycyclic aromatic hydrocarbon(PAHs)in ambient air and ash residues from burning of these wastes pose a great danger ...Open burning of municipal solid waste(MSW)is a common practice in Nigeria.Emission of compounds of polycyclic aromatic hydrocarbon(PAHs)in ambient air and ash residues from burning of these wastes pose a great danger to the environment.This study investigated the contribution of open burning of MSW to the levels of PAHs in ambient air and ash residues from the burning site.Ash samples were obtained from six sampling locations at a MSW burning site.Polyurethane foam passive samplers were used in collecting ambient air samples.Quantification of PAHs was carried out using GC-MS operated in selected ion monitoring mode.The trend of ambient concentration of PAHs was;ΣPAHs AS-A(4.023)>AS-B(3.798)>AS-D(3.468)>AS-C(3.288),while average concentration of PAHs in the ash was 6.12 mg/kg.Concentrations of PAHs in ash samples ranged from 5.69-6.34 mg/kg.Principal component analysis(PCA)showed that most of the PAHs in the ambient were from MSW combustion.The results obtained suggest that concerted effort of the government and the relevant stakeholders is required to safeguard the environment and humans from PAH pollution from open burning of MSW.展开更多
Open biomass burning(OBB)has a significant impact on the heavy haze pollution in Northeast China(NEC)in recent years,which requires the investigation of the spatiotemporal variations of OBB with different vegetation t...Open biomass burning(OBB)has a significant impact on the heavy haze pollution in Northeast China(NEC)in recent years,which requires the investigation of the spatiotemporal variations of OBB with different vegetation types to better monitor and control OBB in NEC.The MODIS C6 fire and land cover products,together with the emissions inventory from the Global Fire Assimilation System,were used in this study.The changes in the total number of MODIS fire points in NEC from 2003 to 2017 demonstrated a fluctuating but generally rising trend,with a peak during 2013–2017.Most fire points concentrated in two key periods,i.e.March–April(37%)and October–November(46%).The total number of crop residue burnings in March–April was basically slightly fluctuating and increased sharply from 2013,whilst the number in October–November had a fluctuating and upward trend until 2015,when a decline appeared.The amount of OBB in March–April was higher than that in October–November during 2016–17.OBB in Heilongjiang Province comprised a major proportion of all fires,which accounted for 70.7%from 2003 to 2017;however,the proportion was only 66.2%during 2013–2017.The largest proportion of all fires was in cropland(90.8%),then forest(5.3%)and grassland(3.1%).The cumulative emissions of fine particulate matter,nitrogen oxides,and ammonia from agricultural open burning in NEC reached 78.43 Gg,24.9 Gg,and 13.7 Gg for March–April during 2013–17,respectively,which were close to those in October–November.展开更多
Black carbon(BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions(BCAn) ...Black carbon(BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions(BCAn) and open biomass burning(BCBB) transported to Xishuangbanna in 2017. Haze months, between haze and clean months, and clean months in Xishuangbanna were defined according to daily PM_(2.5)concentrations of >75, 35–75, and<35 μg/m^(3), respectively. Results showed that the transport efficiency density(TED) of BC transported to Xishuangbanna was controlled by the prevailing winds in different seasons.The yearly contributions to the effective emission intensity of BCAnand BCBBtransported to Xishuangbanna were 52% and 48%, respectively. However, when haze occurred in Xishuangbanna, the average BCAnand BCBBcontributions were 23% and 77%, respectively. This suggests that open biomass burning(BB) becomes the dominant source in haze months. Myanmar, India, and Laos were the dominant source regions of BC transported to Xishuangbanna during haze months, accounting for 59%, 18%, and 13% of the total, respectively. Furthermore, India was identified as the most important source regions of BCAntransported to Xishuangbanna in haze months, accounting for 14%. The two countries making the greatest contributions to BCBBtransported to Xishuangbanna were Myanmar and Laos in haze months, accounting for 55% and 13%, respectively. BC emissions from Xishuangbanna had minimal effects on the results of the present study. It is suggested that open BB in Myanmar and Laos, and anthropogenic emissions in India were responsible for poor air quality in Xishuangbanna.展开更多
Atmospheric particulate and polycyclic aromatic hydrocarbons （PAHs） size distribution were measured at Jhu-Shan （a rural site） and Sin-Gang （a town site） in central Taiwan during the rice straw burning and non-b...Atmospheric particulate and polycyclic aromatic hydrocarbons （PAHs） size distribution were measured at Jhu-Shan （a rural site） and Sin-Gang （a town site） in central Taiwan during the rice straw burning and non-burning periods. The concentrations of total PAHs accounting for a roughly 58% （34%） increment in the concentrations of total PAHs due to rice-straw burning. Combustion-related PAHs during burning periods were 1.54-2.57 times higher than those during non-burning periods. The mass median diameter （MMD） of 0.88-1.21 μm in the particulate phase suggested that rice-straw burning generated the increase in coarse particle number. Chemical mass balance （CMB） receptor model analyses showed that the primary pollution sources at the two sites were similar. However, ricestraw burning emission was specifically identified as a significant source of PAH during burning periods at the two sites. Open burning of rice straws was estimated to contribute approximately 6.3%-24.6% to total atmospheric PAHs at the two sites.展开更多
Air samples were collected simultaneously at Guiyu （an electronic waste recycling site）, three urban sites in Hong Kong and two urban sites in Guangzhou, southeast China on August 20, 2004 and January 24, 2005, resp...Air samples were collected simultaneously at Guiyu （an electronic waste recycling site）, three urban sites in Hong Kong and two urban sites in Guangzhou, southeast China on August 20, 2004 and January 24, 2005, respectively. Seventeen congeners of PCDD/Fs （polychlorinated dibenzo-p-dioxins dibenzofurans） were measured. The results showed that the concentration of PCDD/Fs in Guiyu was 6,721 fg/m3, which was 1.5 times of Guangzhou and 3.1 times of Hong Kong sites. TEQ （total toxic equivalent） of Guiyu, Guangzhou and Hong Kong air samples were 598, 202 and 137 fg I-TEQ/m3, respectively. A clear seasonal variation of PCDD/Fs in the air was found in both Guangzhou and Hong Kong sites. The concentration of 2,3,7,8-TCDD （2,3,7,8-Tetrachlorodibenzodioxin） in Guiyu was 54 fg/m3, higher than the whole year standard of 30 fg/m3 imposed by USA （Indiana, Kansas and Washington）. This was primarily due to the incomplete combustion of e-wastes （e.g., plastic chips, wire insulations, PVC （polyvinyl chloride polymer） materials and metal scraps）.展开更多
The current barrier to acquisition and utilization of viable waste-to-energy (WTE) technologies at remote or deployed expeditionary sites requires high capital and operation & maintenance costs. The impacts to env...The current barrier to acquisition and utilization of viable waste-to-energy (WTE) technologies at remote or deployed expeditionary sites requires high capital and operation & maintenance costs. The impacts to environment and human health of differing expeditionary waste management strategies were compared using the Life Cycle Assessment software SimaPro 8.0. Emissions of individual waste management scenarios were compiled from peer-reviewed literature, converted to values compatible with SimaPro’s waste scenario inputs, and the calculated impacts compared using SimaPro’s pre-loaded methodologies. These calculated impacts and the economic impacts confirm that open-air burning of waste is not only dangerous to humans and the environment, but is also not cost-effective. Considering the economic effects and the mitigated human and environmental health impacts, WTE technologies may be a viable waste management strategy for the future.展开更多
The management of electronic waste(e-waste),which can be a source of both useful materials and toxic substances,depending on the processing method,is important for promoting material cycling.In this study,we used the ...The management of electronic waste(e-waste),which can be a source of both useful materials and toxic substances,depending on the processing method,is important for promoting material cycling.In this study,we used the dioxin-responsive chemical-activated luciferase gene expression(DR-CALUX)assay combined with gas chromatographyehigh-resolution mass spectrometry to evaluate the levels of dioxin-like compounds in surface soils and river sediments collected in and around an e-waste-processing village in northern Vietnam.The WHO-TEQs(Toxic equivalents)of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs),coplanar polychlorinated biphenyls(Co-PCBs),and polybrominated dibenzo-pdioxins and dibenzofurans(PBDD/Fs)in soils collected in January 2012 ranged from 0.29 to 310 pg/g(median 2.9 pg/g,n=32),and the WHO-TEQs in sediments ranged from 0.96 to 58 pg/g(median 4.4 pg/g,n=8).Dioxin-like activities(CALUX-TEQs[2,3,7,8-TCDD equivalent])in soils collected in January 2012,2013,and 2014 ranged from<30 to 4300 pg/g(median<30 pg/g,n=96),and the activities in sediments ranged from<30 to 4000 pg/g(median 33 pg/g,n=24).Dioxin-like compounds accumulated in samples collected around e-waste-processing areas such as open-burning sites and e-waste-processing workshops,and the compounds may be transported from their sources to surrounding areas over the course of several years.Some of the CALUX-TEQs,but not WHO-TEQs,values were higher than the maximum acceptable WHO-TEQs promulgated by various authorities,indicating that all dioxin-like compounds should be evaluated in samples collected from e-waste-processing areas.Our findings suggest that open burning and open storage of e-waste should be prohibited and that wastewater treatment should be implemented at each workshop to reduce contamination by dioxin-like compounds from e-waste.展开更多
The setting up of a country or region-based inventory is considered a crucial step toward the elimination of worldwide persistent organic pollutants(POPs)contamination.Moreover,the need of comparable emission inventor...The setting up of a country or region-based inventory is considered a crucial step toward the elimination of worldwide persistent organic pollutants(POPs)contamination.Moreover,the need of comparable emission inventories at city or region level is widely recognized to develop evidence-based policies accounting for the relation between emissions and institutional,socio-economic and demographic characteristics at small scale level.Due to the low spatial and temporal resolution of the available measurements,highly variable air concentrations of several POPs have been observed in Latin American and Caribbean countries.This paper presents a high resolution spatially disaggregated atmospheric emission inventory for selected POPs in order to assess the environmental fate of some of these compounds in a finer resolution.As study case we estimated releases to air of POPs in a typical mid-size urban conglomeration in Argentina.Inventoried compounds were total polychlorinated biphenyls(PCBs),total polybrominated diphenyl ethers(PBDEs),total dichlorodiphenyltrichloroethane(DDT)on a sum basis,hexachlorobenzene(HCB)and dioxins and furans(PCDD/Fs),for which emissions were estimated in 0.92 kg/year,1.65 kg/year,4.2E-02 kg/year(total sum of congeners),0.86 kg/year and 4.4E-02 kg/year respectively,values that are in accordance with the geographic and economic context.Although emitting sources are quite varied,there are very clear trends,particularly in relation to open burning of municipal solid waste and agrochemical use as major contributors.Overall,the inventory provides valuable data for the analysis of the heterogeneity of POP emissions and the necessary inputs for air quality modeling.展开更多
Inappropriate e-waste-processing operation is a serious issue in developing countries since the early 2000's.Field research was conducted to clarify its influences and diffuse toxic substances in the environment a...Inappropriate e-waste-processing operation is a serious issue in developing countries since the early 2000's.Field research was conducted to clarify its influences and diffuse toxic substances in the environment at e-waste-processing sites in a village in northern Vietnam from 2012 to 2014.We investigated surface soil samples collected from e-waste-processing sites,open burning sites,and rice paddy sites.Sediment samples and water samples were also collected from a river that runs through the village.The hazardous metal concentration in soil and river sediment samples indicated that 7 elements(Ca,Cu,Mo,Ni,Pb,Sn,and Zn)had high concentrations as a result of e-waste-processing.Most notably,Pb and Cu had high concentrations in soil samples(Pb:26e2200 mg/kg,Cu:22e3000 mg/kg).The results of a multivariate analysis indicated that these 7 elements were closely correlated with e-waste-processing.Concentrations of hazardous metals showed an upward trend where e-waste-processing occurred during the 3-year study period,although it was not significant statistically at present.Open burning activity had a great influence on Cu accumulation,and maximum Cu concentrations increased from 340 mg/kg in 2012e3000 mg/kg in 2014 in soil samples from open-burning sites.There were large differences in the dominant hazardous metal depending on the type of e-waste-processing workshop because hazardous metal composition was influenced by the types of e-waste and the processing procedures.It is necessary to avoid e-waste processing in open-air environment to control emissions of hazardous substances.Especially,open burning should be prohibited.展开更多
This study analyzed the characteristics of air pollution and specific pollution periods within the HarbinChangchun(HC)metropolitan area during 2014e2020.Regarding annual,seasonal,and monthly variations of the six po...This study analyzed the characteristics of air pollution and specific pollution periods within the HarbinChangchun(HC)metropolitan area during 2014e2020.Regarding annual,seasonal,and monthly variations of the six pollutants,the change trend in 11 cities of HC showed strong consistency in spatial distribution.The western cities(Songyuan,Daqing,and Siping)were vulnerable to dust storms from Inner Mongolia.The concentrations of all air pollutants,except O3-8h,showed downward fluctuation trends from 2014 to 2018 and remained stable from 2018 to 2020 in terms of annual variations.The interannual trend of significant reductions in SO2 and SO2/PM2.5 during the heating period indicated that strict emission reduction measures posed by the government were highly successful.The ratio of PM2.5/SO2 was used to identify open biomass burning(OBB),which showed a double peak(OctobereNovember(OcteNov),MarcheApril(MareApr)).The burning prohibition shifted the OBB from OcteNov to Mar eApr.展开更多
基金supported by the National Key Research and Development Program of China(No.2016YFC0208500)the Tianjin Science and Technology Program(No.18ZXSZSF00160)the Fundamental Research Funds for the Central Universities of China(Nos.ZB19500210,ZB19000804).
文摘Crop residue open burning is an important emission source of ambient particles in China.This study analyzed the particle emission characteristics of crop residue open burning through combustion experiments with a novel open combustion simulation device using three typical crop straws in north China(corn,wheat,and rice).Particle samples size ranging from 0.006–9.890μm were collected by an Electrical Low Pressure Impactor plus,a high size-resolution instrument capable of dividing particles into 14 size stages.The size distributions of organic carbon(OC),elemental carbon(EC),water-soluble ions,and elements were analyzed,and source chemical profiles were constructed for PM0.1,PM1,PM2.5,and PM10.The number concentration of particles was concentrated in the Aiken nuclei mode(0.006–0.054μm),accounting for 75%of the total number,whereas the mass concentration was concentrated in the accumulation mode(0.054–0.949μm),accounting for 85.43%of the mass loading.OC,EC,Cl−,and K(include total K and water-soluble K)were the major chemical components of the particles,whose mass percentage distributions differed from those of other components.These fivemain components exhibited a bell-shaped size distribution in the 0.006–9.890μm range,whereas the other components exhibited a U-shaped distribution.Among the chemical profiles for PM0.1–PM10,OC was the most important component at 10–30%,followed by EC at 2%–8%.The proportions of K^(+),Cl^(−),and K varied substantially in different experimental groups,ranging from 0–15%,and K+and Cl−were significantly correlated(r=0.878,α=0.000).
基金supported by the Environmental Protection Ministry of China for Research of Characteristics and Controlling Measures of VOCs Emissions from Typical Anthropogenic Sources (No. 2011467003)the Natural Science Foundation key project (grant no. 91544106)
文摘With the objective of reducing the large uncertainties in the estimations of emissions from crop residue open burning, an improved method for establishing emission inventories of crop residue open burning at a high spatial resolution of 0.25°× 0.25° and a temporal resolution of1 month was established based on the moderate resolution imaging spectroradiometer（MODIS） Thermal Anomalies/Fire Daily Level3 Global Product（MOD/MYD14A1）. Agriculture mechanization ratios and regional crop-specific grain-to-straw ratios were introduced to improve the accuracy of related activity data. Locally observed emission factors were used to calculate the primary pollutant emissions. MODIS satellite data were modified by combining them with county-level agricultural statistical data, which reduced the influence of missing fire counts caused by their small size and cloud cover. The annual emissions of CO2, CO, CH4,nonmethane volatile organic compounds（NMVOCs）, N2O, NOx, NH3, SO2, fine particles（PM2.5）,organic carbon（OC）, and black carbon（BC） were 150.40, 6.70, 0.51, 0.88, 0.01, 0.13, 0.07, 0.43,1.09, 0.34, and 0.06 Tg, respectively, in 2012. Crop residue open burning emissions displayed typical seasonal and spatial variation. The highest emission regions were the Yellow-Huai River and Yangtse-Huai River areas, and the monthly emissions were highest in June（37%）.Uncertainties in the emission estimates, measured as 95% confidence intervals, range from a low of within ±126% for N2O to a high of within ± 169% for NH3.
文摘Open burning of municipal solid waste(MSW)is a common practice in Nigeria.Emission of compounds of polycyclic aromatic hydrocarbon(PAHs)in ambient air and ash residues from burning of these wastes pose a great danger to the environment.This study investigated the contribution of open burning of MSW to the levels of PAHs in ambient air and ash residues from the burning site.Ash samples were obtained from six sampling locations at a MSW burning site.Polyurethane foam passive samplers were used in collecting ambient air samples.Quantification of PAHs was carried out using GC-MS operated in selected ion monitoring mode.The trend of ambient concentration of PAHs was;ΣPAHs AS-A(4.023)>AS-B(3.798)>AS-D(3.468)>AS-C(3.288),while average concentration of PAHs in the ash was 6.12 mg/kg.Concentrations of PAHs in ash samples ranged from 5.69-6.34 mg/kg.Principal component analysis(PCA)showed that most of the PAHs in the ambient were from MSW combustion.The results obtained suggest that concerted effort of the government and the relevant stakeholders is required to safeguard the environment and humans from PAH pollution from open burning of MSW.
基金partially supported by the National Natural Science Foundation of China grant number 41775162
文摘Open biomass burning(OBB)has a significant impact on the heavy haze pollution in Northeast China(NEC)in recent years,which requires the investigation of the spatiotemporal variations of OBB with different vegetation types to better monitor and control OBB in NEC.The MODIS C6 fire and land cover products,together with the emissions inventory from the Global Fire Assimilation System,were used in this study.The changes in the total number of MODIS fire points in NEC from 2003 to 2017 demonstrated a fluctuating but generally rising trend,with a peak during 2013–2017.Most fire points concentrated in two key periods,i.e.March–April(37%)and October–November(46%).The total number of crop residue burnings in March–April was basically slightly fluctuating and increased sharply from 2013,whilst the number in October–November had a fluctuating and upward trend until 2015,when a decline appeared.The amount of OBB in March–April was higher than that in October–November during 2016–17.OBB in Heilongjiang Province comprised a major proportion of all fires,which accounted for 70.7%from 2003 to 2017;however,the proportion was only 66.2%during 2013–2017.The largest proportion of all fires was in cropland(90.8%),then forest(5.3%)and grassland(3.1%).The cumulative emissions of fine particulate matter,nitrogen oxides,and ammonia from agricultural open burning in NEC reached 78.43 Gg,24.9 Gg,and 13.7 Gg for March–April during 2013–17,respectively,which were close to those in October–November.
基金supported by the National Natural Science Foundation of China (Nos. 41705109 and 41805098)State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex (No. SCAPC_(2)02001)+1 种基金State Key Laboratory of Severe Weather & Key Laboratory for Atmospheric Chemistry (No. 2018B04)Tsinghua National Laboratory for Information Science and Technology。
文摘Black carbon(BC) has importance regarding aerosol composition, radiative balance, and human exposure. This study adopted a backward-trajectory approach to quantify the origins of BC from anthropogenic emissions(BCAn) and open biomass burning(BCBB) transported to Xishuangbanna in 2017. Haze months, between haze and clean months, and clean months in Xishuangbanna were defined according to daily PM_(2.5)concentrations of >75, 35–75, and<35 μg/m^(3), respectively. Results showed that the transport efficiency density(TED) of BC transported to Xishuangbanna was controlled by the prevailing winds in different seasons.The yearly contributions to the effective emission intensity of BCAnand BCBBtransported to Xishuangbanna were 52% and 48%, respectively. However, when haze occurred in Xishuangbanna, the average BCAnand BCBBcontributions were 23% and 77%, respectively. This suggests that open biomass burning(BB) becomes the dominant source in haze months. Myanmar, India, and Laos were the dominant source regions of BC transported to Xishuangbanna during haze months, accounting for 59%, 18%, and 13% of the total, respectively. Furthermore, India was identified as the most important source regions of BCAntransported to Xishuangbanna in haze months, accounting for 14%. The two countries making the greatest contributions to BCBBtransported to Xishuangbanna were Myanmar and Laos in haze months, accounting for 55% and 13%, respectively. BC emissions from Xishuangbanna had minimal effects on the results of the present study. It is suggested that open BB in Myanmar and Laos, and anthropogenic emissions in India were responsible for poor air quality in Xishuangbanna.
基金The Central Taiwan University of Science and Technology supported this work under the grant 94-INS-024
文摘Atmospheric particulate and polycyclic aromatic hydrocarbons （PAHs） size distribution were measured at Jhu-Shan （a rural site） and Sin-Gang （a town site） in central Taiwan during the rice straw burning and non-burning periods. The concentrations of total PAHs accounting for a roughly 58% （34%） increment in the concentrations of total PAHs due to rice-straw burning. Combustion-related PAHs during burning periods were 1.54-2.57 times higher than those during non-burning periods. The mass median diameter （MMD） of 0.88-1.21 μm in the particulate phase suggested that rice-straw burning generated the increase in coarse particle number. Chemical mass balance （CMB） receptor model analyses showed that the primary pollution sources at the two sites were similar. However, ricestraw burning emission was specifically identified as a significant source of PAH during burning periods at the two sites. Open burning of rice straws was estimated to contribute approximately 6.3%-24.6% to total atmospheric PAHs at the two sites.
文摘Air samples were collected simultaneously at Guiyu （an electronic waste recycling site）, three urban sites in Hong Kong and two urban sites in Guangzhou, southeast China on August 20, 2004 and January 24, 2005, respectively. Seventeen congeners of PCDD/Fs （polychlorinated dibenzo-p-dioxins dibenzofurans） were measured. The results showed that the concentration of PCDD/Fs in Guiyu was 6,721 fg/m3, which was 1.5 times of Guangzhou and 3.1 times of Hong Kong sites. TEQ （total toxic equivalent） of Guiyu, Guangzhou and Hong Kong air samples were 598, 202 and 137 fg I-TEQ/m3, respectively. A clear seasonal variation of PCDD/Fs in the air was found in both Guangzhou and Hong Kong sites. The concentration of 2,3,7,8-TCDD （2,3,7,8-Tetrachlorodibenzodioxin） in Guiyu was 54 fg/m3, higher than the whole year standard of 30 fg/m3 imposed by USA （Indiana, Kansas and Washington）. This was primarily due to the incomplete combustion of e-wastes （e.g., plastic chips, wire insulations, PVC （polyvinyl chloride polymer） materials and metal scraps）.
文摘The current barrier to acquisition and utilization of viable waste-to-energy (WTE) technologies at remote or deployed expeditionary sites requires high capital and operation & maintenance costs. The impacts to environment and human health of differing expeditionary waste management strategies were compared using the Life Cycle Assessment software SimaPro 8.0. Emissions of individual waste management scenarios were compiled from peer-reviewed literature, converted to values compatible with SimaPro’s waste scenario inputs, and the calculated impacts compared using SimaPro’s pre-loaded methodologies. These calculated impacts and the economic impacts confirm that open-air burning of waste is not only dangerous to humans and the environment, but is also not cost-effective. Considering the economic effects and the mitigated human and environmental health impacts, WTE technologies may be a viable waste management strategy for the future.
基金supported by the Society for the Promotion of Science and Environment Research and Technology Development Fund(no.3K133010 and no.3K153001)of the Ministry of the Environment,Japansupported by the Ministry of Education,Culture,Sports,Science and Technology,Japan(MEXT)to a project on Center of Excellence for Cooperative and Collaborative Studies e Leading Academia in Marine and Environmental Research(LaMer).
文摘The management of electronic waste(e-waste),which can be a source of both useful materials and toxic substances,depending on the processing method,is important for promoting material cycling.In this study,we used the dioxin-responsive chemical-activated luciferase gene expression(DR-CALUX)assay combined with gas chromatographyehigh-resolution mass spectrometry to evaluate the levels of dioxin-like compounds in surface soils and river sediments collected in and around an e-waste-processing village in northern Vietnam.The WHO-TEQs(Toxic equivalents)of polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs),coplanar polychlorinated biphenyls(Co-PCBs),and polybrominated dibenzo-pdioxins and dibenzofurans(PBDD/Fs)in soils collected in January 2012 ranged from 0.29 to 310 pg/g(median 2.9 pg/g,n=32),and the WHO-TEQs in sediments ranged from 0.96 to 58 pg/g(median 4.4 pg/g,n=8).Dioxin-like activities(CALUX-TEQs[2,3,7,8-TCDD equivalent])in soils collected in January 2012,2013,and 2014 ranged from<30 to 4300 pg/g(median<30 pg/g,n=96),and the activities in sediments ranged from<30 to 4000 pg/g(median 33 pg/g,n=24).Dioxin-like compounds accumulated in samples collected around e-waste-processing areas such as open-burning sites and e-waste-processing workshops,and the compounds may be transported from their sources to surrounding areas over the course of several years.Some of the CALUX-TEQs,but not WHO-TEQs,values were higher than the maximum acceptable WHO-TEQs promulgated by various authorities,indicating that all dioxin-like compounds should be evaluated in samples collected from e-waste-processing areas.Our findings suggest that open burning and open storage of e-waste should be prohibited and that wastewater treatment should be implemented at each workshop to reduce contamination by dioxin-like compounds from e-waste.
基金supported by the National Scientific and Technical Research Council(CONICET,PIP#11220110100673)National Agency for Scientific and Technological Promotion(ANPCyT),Universidad Tecnologica Nacional(Grant Project#PID UTN IFI1487 Cod.25/JC01)Argentina,Universidad Nacional de Cuyo and Organization for Prohibition of Chemical Weapons.
文摘The setting up of a country or region-based inventory is considered a crucial step toward the elimination of worldwide persistent organic pollutants(POPs)contamination.Moreover,the need of comparable emission inventories at city or region level is widely recognized to develop evidence-based policies accounting for the relation between emissions and institutional,socio-economic and demographic characteristics at small scale level.Due to the low spatial and temporal resolution of the available measurements,highly variable air concentrations of several POPs have been observed in Latin American and Caribbean countries.This paper presents a high resolution spatially disaggregated atmospheric emission inventory for selected POPs in order to assess the environmental fate of some of these compounds in a finer resolution.As study case we estimated releases to air of POPs in a typical mid-size urban conglomeration in Argentina.Inventoried compounds were total polychlorinated biphenyls(PCBs),total polybrominated diphenyl ethers(PBDEs),total dichlorodiphenyltrichloroethane(DDT)on a sum basis,hexachlorobenzene(HCB)and dioxins and furans(PCDD/Fs),for which emissions were estimated in 0.92 kg/year,1.65 kg/year,4.2E-02 kg/year(total sum of congeners),0.86 kg/year and 4.4E-02 kg/year respectively,values that are in accordance with the geographic and economic context.Although emitting sources are quite varied,there are very clear trends,particularly in relation to open burning of municipal solid waste and agrochemical use as major contributors.Overall,the inventory provides valuable data for the analysis of the heterogeneity of POP emissions and the necessary inputs for air quality modeling.
文摘Inappropriate e-waste-processing operation is a serious issue in developing countries since the early 2000's.Field research was conducted to clarify its influences and diffuse toxic substances in the environment at e-waste-processing sites in a village in northern Vietnam from 2012 to 2014.We investigated surface soil samples collected from e-waste-processing sites,open burning sites,and rice paddy sites.Sediment samples and water samples were also collected from a river that runs through the village.The hazardous metal concentration in soil and river sediment samples indicated that 7 elements(Ca,Cu,Mo,Ni,Pb,Sn,and Zn)had high concentrations as a result of e-waste-processing.Most notably,Pb and Cu had high concentrations in soil samples(Pb:26e2200 mg/kg,Cu:22e3000 mg/kg).The results of a multivariate analysis indicated that these 7 elements were closely correlated with e-waste-processing.Concentrations of hazardous metals showed an upward trend where e-waste-processing occurred during the 3-year study period,although it was not significant statistically at present.Open burning activity had a great influence on Cu accumulation,and maximum Cu concentrations increased from 340 mg/kg in 2012e3000 mg/kg in 2014 in soil samples from open-burning sites.There were large differences in the dominant hazardous metal depending on the type of e-waste-processing workshop because hazardous metal composition was influenced by the types of e-waste and the processing procedures.It is necessary to avoid e-waste processing in open-air environment to control emissions of hazardous substances.Especially,open burning should be prohibited.
基金This work was supported by the National Natural Science Foundation of China(41805097).
文摘This study analyzed the characteristics of air pollution and specific pollution periods within the HarbinChangchun(HC)metropolitan area during 2014e2020.Regarding annual,seasonal,and monthly variations of the six pollutants,the change trend in 11 cities of HC showed strong consistency in spatial distribution.The western cities(Songyuan,Daqing,and Siping)were vulnerable to dust storms from Inner Mongolia.The concentrations of all air pollutants,except O3-8h,showed downward fluctuation trends from 2014 to 2018 and remained stable from 2018 to 2020 in terms of annual variations.The interannual trend of significant reductions in SO2 and SO2/PM2.5 during the heating period indicated that strict emission reduction measures posed by the government were highly successful.The ratio of PM2.5/SO2 was used to identify open biomass burning(OBB),which showed a double peak(OctobereNovember(OcteNov),MarcheApril(MareApr)).The burning prohibition shifted the OBB from OcteNov to Mar eApr.
