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Source apportionment and heavy metal health risk (HMHR) quantification from sources in a southern city in China, using an ME2-HMHR model
2016
Peng, Xing | Shi, Guoliang | Liu, Guirong | Xu, Jiao | Tian, YingZe | Zhang, Yufen | Feng, YinChang | Russell, Armistead G.
Heavy metals (Cr, Co, Ni, As, Cd, and Pb) can be bound to PM adversely affecting human health. Quantifying the source impacts on heavy metals can provide source-specific estimates of the heavy metal health risk (HMHR) to guide effective development of strategies to reduce such risks from exposure to heavy metals in PM2.5 (particulate matter (PM) with aerodynamic diameter less than or equal to 2.5 μm). In this study, a method combining Multilinear Engine 2 (ME2) and a risk assessment model is developed to more effectively quantify source contributions to HMHR, including heavy metal non-cancer risk (non-HMCR) and cancer risk (HMCR). The combined model (called ME2-HMHR) has two steps: step1, source contributions to heavy metals are estimated by employing the ME2 model; step2, the source contributions in step 1 are introduced into the risk assessment model to calculate the source contributions to HMHR. The approach was applied to Huzou, China and five significant sources were identified. Soil dust is the largest source of non-HMCR. For HMCR, the source contributions of soil dust, coal combustion, cement dust, vehicle, and secondary sources are 1.0 × 10−4, 3.7 × 10−5, 2.7 × 10−6, 1.6 × 10−6 and 1.9 × 10−9, respectively. The soil dust is the largest contributor to HMCR, being driven by the high impact of soil dust on PM2.5 and the abundance of heavy metals in soil dust.
Show more [+] Less [-]Wintertime haze deterioration in Beijing by industrial pollution deduced from trace metal fingerprints and enhanced health risk by heavy metals
2016
Lin, Yu-Chi | Xu, Shijie | Chou, Charles C.-K. | Zhang, Renjian | Wu, Yunfei | Kao, Shuh-Ji | Luo, Li | Huang, Chao-Hao | Lin, Shuen-Hsin | Huang, Yi-Tang
Airborne particulate matter (PM) was collected in Beijing between 24 February and 12 March 2014 to investigate chemical characteristics and potential industrial sources of aerosols along with health risk of haze events. Results showed secondary inorganic aerosol was the major contributor to PM2.5 during haze days. Utilizing specific elements, including Fe, La, Tl and As, as fingerprinting tracers, four emission sources, namely iron and steel manufacturing, petroleum refining, cement plant, and coal combustion were explicitly identified; their elevated contributions to PM during haze days were also estimated. The average cancer risk from exposure to inhalable PM toxic metals was 1.53 × 10⁻⁴ on haze days, which is one order of magnitude higher than in other developed cities. These findings suggested heavy industries emit large amounts of not only primary PM but also precursor gas pollutants, leading to secondary aerosol formation and harm to human health during haze days.
Show more [+] Less [-]Distribution, sources and ecological risk assessment of PAHs in historically contaminated surface sediments at Bhavnagar coast, Gujarat, India
2016
Dudhagara, Dushyant R. | Rajpara, Rahul K. | Bhatt, Jwalant K. | Gosai, Haren B. | Sachaniya, Bhumi K. | Dave, Bharti P.
The concentration, distribution and ecological risk of polycyclic aromatic hydrocarbons (PAHs) have been investigated in surface sediments near Bhavnagar coast. The concentration of ∑PAHs ranged from 5.02 to 981.18 μg g−1 dry weight, indicating heavy pollution compared to other historically polluted study sites. It was found to be introduced via mixed origins such as burning of gas, oil, coal, production of petrochemicals, cement, and rubber tires. Domestic fuel burning and motor vehicles are also culprits for air pollution. Industrial effluents and accidental oil spillage can also be considered. PAHs can be exposed through air, water, soil and food sources including ingestion, inhalation, and dermal content in both occupational and non-occupational levels by single or sometimes multiple exposures routes concomitantly. Furthermore, diagnostic ratios, statistical principal component analysis (PCA) and hierarchical cluster analysis (HCA) models have confirmed that the sources of PAHs were both - petrogenic and pyrogenic. For both the sites, assessment of ecological risk of the elevated levels of these pollutants has been exercised based on toxic equivalency factors (TEFs) and risk quotient (RQ) methods. The composite results indicated accurately that both the sites, bears potentially acute and chronic health hazards such as decreased immune functionality, genotoxicity, malignancy and developmental malfunctions in humans. The sites studied here and the workers have been exposed to hazardous pollutants for a longer period of time. Evidences indicate that mixtures of PAHs are carcinogenic to humans, based on occupational studies on workers, exposed to these pollutants. Hence, the present study and statistical approaches applied herein clearly indicate the historic mix routes of PAHs that resulted in magnified concentrations leading to high ecosystem risk. Thus, the scientific communities are urged to develop strategies to minimize the concentrations of PAHs from the historically impacted coastlines, thereby concerning for the future investigations and restoration of these sites.
Show more [+] Less [-]SPECIEUROPE: The European data base for PM source profiles
2016
Pernigotti, Denise | Belis, Claudio A. | Spanò, Luca
A new database of atmospheric particulate matter emission source profiles in Europe (SPECIEUROPE) developed in the framework of the Forum for air quality modeling in Europe (FAIRMODE, Working Group 3) is accessible at the website http://source-apportionment.jrc.ec.europa.eu/Specieurope/index.aspx. It contains the chemical composition of particulate matter emission sources reported in the scientific literature and reports drafted by competent authorities. The first release of SPECIEUROPE consists of 151 measured (original), 13 composite (merging different subcategories of similar sources), 6 calculated (from stoichiometric composition) and 39 derived (results of source apportionment studies) profiles. Each profile is related to one or more source categories or subcategories. The sources with the highest PM relative mass toxic pollutants such as PAHs are fuel oil burning, ship emissions, coke burning and wood burning. Heavy metals are most abundant in metal processing activities while halogens are mostly present in fertilizer production, coal burning and metallurgic sector. Anhydrosugars are only measured in biomass and wood burning source categories, because are markers for these categories. The alkaline earth metals are mostly present in road dust, cement production, soil dust and sometimes coal burning. Source categories like traffic and industrial, which contain heterogeneous subcategories, show the greatest internal variability.The relationships between sources profiles were also explored using a cluster analysis approach based upon the Standardized Identity Distance (SID) indicator. The majority of profiles are allocated in 8 major clusters. Some of the clusters include profiles mainly from one source category (e.g. wood burning) while others, such as industrial source profiles, are more heterogeneous and spread over three different clusters.
Show more [+] Less [-]Use of Amendments to Restore Ecosystem Function to Metal Mining-Impacted Sites: Tools to Evaluate Efficacy
2016
Brown, Sally L. | Chaney, Rufus L.
As in situ use of amendments for restoration of metal-contaminated mining sites becomes increasingly accepted, the expected level of ecosystem function at these sites will increase. Use of appropriate tools to measure both the level and value of that function is critical to expand use of this approach. For these sites, amendment mixtures must reduce metal availability in situ and restore ecosystem function. Combinations of mixtures, typically consisting of a material with high metal binding capacity (cyclonic ashes, municipal biosolids, or other materials rich in Fe, Al, or Mn oxides), material to adjust soil pH (sugar beet lime, cement kiln dust, dolomitic limestone), and an organic residual to provide soil structure and nutrients (composts, animal manures, municipal biosolids) have been tested in multiple lab and field trials on metal-contaminated sites. This review focuses on field tests of this approach with the goal of providing methods to quantify reduction of hazard and restoration of functional systems. Methods to evaluate success of amendments including extractions to measure changes in metal availability, microbial function and diversity, phytoavailability of metals, and earthworm and small mammal assays are discussed. In most cases, measures of metal availability and ecosystem function are related. For example, surveys of small mammals on restored sites provide information on metal availability as well as suitability of restored habitat. Additional measures of ecosystem function including soil fertility, physical properties, and diversity of habitat are described. Finally, measures of the value of this approach for restoring ecosystems are detailed.
Show more [+] Less [-]Chemical Properties of Various Chimney Ejecting Fly Ashes
2016
For the purpose of clarifying the chemical nature of fly ashes, the raw fly ashes were collected from the stacks of 17 fixed sources consisting of 15 municipal waste incinerators, a metal melting factory, and a cement plant all of which are located in the western Japan from Nov. 2000 to Jan. 2007. The municipal waste incinerators were successfully classified into four groups in terms of the relative mass ratios between chloride, potassium, and sodium. Sodium, potassium, and calcium were found abundantly in fly ashes collected from all four types of municipal waste incinerators. The theoretical estimation of chlorine form suggested that the form of NaCI, KCl, MgCl, and CaCl₂ accounted for approximately 55 % of total chlorine in raw fly ash. Trace heavy metals (i.e., Zn, Mn, Pb, Cu, Cr, Ni, and V) were preferentially enriched in the ambient PM₂.₅ which was strongly influenced by regional stationary sources (including municipal waste incinerators). The water-soluble OC to TC fraction in the fly ashes of municipal waste incinerator, metal furnace, and cement plant was estimated as 56.8, 79.0, and 89.6 %, respectively.
Show more [+] Less [-]Leaf structural traits of tropical woody species resistant to cement dust
2016
Siqueira-Silva, Advanio Inácio | Pereira, Eduardo Gusmão | Modolo, Luzia Valentina | Paiva, Elder Antonio Sousa
Cement industries located nearby limestone outcrops in Brazil have contributed to the coating of cement dust over native plant species. However, little is known about the extent of the response of tropical woody plants to such environmental pollutant particularly during the first stages of plant development and establishment. This work focused on the investigation of possible alterations in leaf structural and ultrastructural traits of 5-month-old Guazuma ulmifolia Lam. (Malvaceae), 6-month-old Myracrodruon urundeuva Allemão (Anacardiaceae), and 9-month-old Trichilia hirta L. (Meliaceae) challenged superficially with cement dust during new leaf development. Leaf surface of plants, the soil or both (leaf plus soil), were treated (or not) for 60 days, under controlled conditions, with cement dust at 2.5 or 5.0 mg cm⁻². After exposure, no significant structural changes were observed in plant leaves. Also, no plant death was recorded by the end of the experiment. There was also some evidence of localized leaf necrosis in G. ulmifolia and T. hirta, leaf curling in M. urundeuva and T. hirta, and bulges formation on epidermal surface of T. hirta, after cement dust contact with plant shoots. All species studied exhibited stomata obliteration while T. hirta, in particular, presented early leaf abscission, changes in cellular relief, and organization and content of midrib cells. No significant ultrastructural alterations were detected under the experimental conditions studied. Indeed, mesophyll cells presented plastids with intact membrane systems. The high plant survival rates, together with mild morphoanatomic traits alterations in leaves, indicate that G. ulmifolia is more resistant to cement dust pollutant, followed by M. urundeuva and T. hirta. Thus, the three plant species are promising for being used to revegetate areas impacted by cement industries activities.
Show more [+] Less [-]Technical feasibility study of a low-cost hybrid PAC-UF system for wastewater reclamation and reuse: a focus on feedwater production for low-pressure boilers
2016
Amosa, Mutiu Kolade | Jami, Mohammed Saedi | Alkhatib, Ma’an Fahmi R. | Majozi, Thokozani
This study has applied the concept of the hybrid PAC-UF process in the treatment of the final effluent of the palm oil industry for reuse as feedwater for low-pressure boilers. In a bench-scale set-up, a low-cost empty fruit bunch-based powdered activated carbon (PAC) was employed for upstream adsorption of biotreated palm oil mill effluent (BPOME) with the process conditions: 60 g/L dose of PAC, 68 min of mixing time and 200 rpm of mixing speed, to reduce the feedwater strength, alleviate probable fouling of the membranes and thus improve the process flux (productivity). Three polyethersulfone ultrafiltration membranes of molecular weight cut-off (MWCO) of 1, 5 and 10 kDa were investigated in a cross-flow filtration mode, and under constant transmembrane pressures of 40, 80, and 120 kPa. The permeate qualities of the hybrid processes were evaluated, and it was found that the integrated process with the 1 kDa MWCO UF membrane yielded the best water quality that falls within the US EPA reuse standard for boiler-feed and cooling water. It was also observed that the permeate quality is fit for extended reuse as process water in the cement, petroleum and coal industries. In addition, the hybrid system’s operation consumed 37.13 Wh m⁻³ of energy at the highest applied pressure of 120 kPa, which is far lesser than the typical energy requirement range (0.8–1.0 kWh m⁻³) for such wastewater reclamation.
Show more [+] Less [-]Effects of bypass system on PCDD/F emission and chlorine circulation in cement kilns
2016
Zhan, Ming-Xiu | Fu, Jianying | Chen, Tong | Li Yeqing, | Zhang, Jiang | Li, Xiao-Dong | Yan, Jian-Hua | Buekens, Alfons
A bypass at the kiln inlet allows the effective reduction of alkali chloride cycles and thus perhaps affects the emission of PCDD/Fs. Effects of bypass system on PCDD/F emission and chlorine circulation were studied in two typical dry cement kilns with 5000 ton/day clinker capacity in China and named CK1 and CK2, respectively. Firstly, the emission level of PCDD/Fs with the operation of bypass system was estimated in CK1, to certify that bypass system has a perfect adaption to the cement kiln regarding the PCDD/F emission even with the refuse derived fuel (RDF) as the replacement of fuel. On the other hand, the operating conditions in the CK2 were scrutinised by monitoring the concentrations of SO₂, NH₃ and HCl. In addition, the characteristics of raw meal, clinker, bag filter ash and bypass ash were also investigated by Energy Dispersive Spectrometer (EDS), metal and chlorine analysis. The balance of chlorine showed that 18 % of the possible accumulated chlorine could be ejected from the cement kiln system when 2 % of kiln exhaust gas was extracted. Furthermore, the emission level of PCDD/Fs in the main flue gas also decreased from 0.037 ± 0.035 ng I-TEQ/Nm³ to 0.019 ± 0.007 ng I-TEQ/Nm³ with a reduction efficiency of 48.2 %. Most importantly, PCDD/F emission from the bypass system was proven to have rather minor effect on the total emission factor. The congener distributions of PCDD/Fs were also analysed in the flue gas and fly ash, before and after application of bypass system, to find cues to the formation mechanism.
Show more [+] Less [-]Volcano-related materials in concretes: a comprehensive review
2016
Cai, Gaochuang | Noguchi, Takafumi | Degée, Hervé | Zhao, Jun | Kitagaki, Ryoma
Massive volcano-related materials (VRMs) erupted from volcanoes bring the impacts to natural environment and humanity health worldwide, which include generally volcanic ash (VA), volcanic pumice (VP), volcanic tuff (VT), etc. Considering the pozzolanic activities and mechanical characters of these materials, civil engineers propose to use them in low carbon/cement and environment-friendly concrete industries as supplementary cementitious materials (SCMs) or artificial/natural aggregates. The utilization of VRMs in concretes has attracted increasing and pressing attentions from research community. Through a literature review, this paper presents comprehensively the properties of VRMs and VRM concretes (VRMCs), including the physical and chemical properties of raw VRMs and VRMCs, and the fresh, microstructural and mechanical properties of VRMCs. Besides, considering environmental impacts and the development of long-term properties, the durability and stability properties of VRMCs also are summarized in this paper. The former focuses on the resistance properties of VRMCs when subjected to aggressive environmental impacts such as chloride, sulfate, seawater, and freezing–thawing. The latter mainly includes the fatigue, creep, heat-insulating, and expansion properties of VRMCs. This study will be helpful to promote the sustainability in concrete industries, protect natural environment, and reduce the impacts of volcano disaster. Based on this review, some main conclusions are discussed and important recommendations regarding future research on the application of VRMs in concrete industries are provided.
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