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Trends of production, consumption and environmental emissions of Decabromodiphenyl ether in mainland China Texto completo
2020
Chen, Yuan | Li, Jinhui | Tan, Quanyin
Decabromodiphenyl ether (DecaBDE) is a brominated flame retardant belonging to the group of polybrominated diphenyl ethers. DecaBDE has been widely used for various applications, such as plastics, textiles, and building and construction materials. Limited information on DecaBDE production and usage inventory has been elaborated, however. Therefore, this work aimed to produce a preliminary emissions inventory of DecaBDE in mainland China by estimating production and consumption amounts of DecaBDE, and characterizing its emission factors during production and usage, based on industrial investigation and theoretical prediction. It was indicated that the total production of DecaBDE reached 464.68 thousand metric tons (kt), of which 62.72 kt were exported, since the beginning of its production. Shandong and Jiangsu provinces dominate the production, with proportions of 77.95% and 18.45%, respectively. The production stage releases most of the DecaBDE to the atmosphere, with an emissions factor of 23 ± 1.9 kg/t, followed by 20 ± 0.9 kg/t DecaBDE to waste water and 16 ± 1.0 kg/t DecaBDE as solid residue. DecaBDE emissions in the consumption stage—namely the plastic production process—are 0.17 ± 0.06–0.23 ± 0.08 kg DecaBDE to the atmosphere and 1.72 ± 0.58–2.29 ± 0.77 kg DecaBDE to solid residue, for each metric ton of plastic produced. The total annual DecaBDE emissions to waste water are 93.98–1140.9 mg—negligible. The results showed that the sources of DecaBDE environmental pollution are its manufacturing and flame-retardant plastic modification plants, which are easily overlooked by both the government and the public. Yet DecaBDE emissions elimination and the environmentally sound management of the DecaBDE waste generated from these two processes are crucial for environmental protection.
Mostrar más [+] Menos [-]Indoor vs. outdoor airborne element array: A novel approach using moss bags to explore possible pollution sources Texto completo
2019
Capozzi, F. | Di Palma, A. | Adamo, P. | Sorrentino, M.C. | Giordano, S. | Spagnuolo, V.
This study investigated by the moss-bag approach the pattern of air dispersed elements in 12 coupled indoor/outdoor exposure sites, all located in urban and rural residential areas. The aims were to discriminate indoor vs. outdoor element composition in coupled exposure sites and find possible relation between moss elemental profile and specific characteristics of each exposure site.Elements were considered enriched when in 60% of the sites, post-exposure concentration exceeded pre-exposure concentration plus two folds the standard deviation. Of the 53 analyzed elements, 15 (As, B, Ca, Co, Cr, Cu, Mn, Mo, Ni, Sb, Se, Sn, Sr, V, Zn) were enriched in moss exposed outdoor, whereas a subset of 7 elements (As, B, Cr, Mo, Ni, Se, V) were enriched also in indoor moss samples. The cluster analysis of the sites based on all elements, clearly separated samples in two groups corresponding to mosses exposed indoor and outdoor, with the latter generally exceeding the first. Among outdoor sites, urban were most impacted than rural; whereas other factors (e.g., heating and cooking systems, building material, residence time and family life style) could affect element profile of indoor environments. Based on the indoor/outdoor ratio, As derived from outdoor and indoor sources, B, Mo and Se were enriched mostly in outdoor sites; Ni, Cr and V were specifically enriched in most indoor samples, supporting the presence of indoor emitting sources for these elements. A PCA of all indoor sites based on enriched elements and site characteristics showed that traffic affected indoor pollution in urban areas. The moss bag approach provided useful information for a global assessment of human exposure.
Mostrar más [+] Menos [-]Solute pools in Nikanotee Fen watershed in the Athabasca oil sands region Texto completo
2017
Simhayov, Reuven B. | Price, Jonathan S. | Smeaton, Christina M. | Parsons, Chris | Rezanezhad, Fereidoun | Van Cappellen, Philippe
Overburden and tailings materials from oil sands production were used as construction materials as part of a novel attempt to create a self-sustaining, peat accumulating fen-upland ecosystem. To evaluate the potential for elemental release from the construction materials, total elemental concentrations in the tailings sand, petroleum coke and peat used to construct a fen ecosystem were determined using microwave-assisted acid digestions and compared to a leaching experiment conducted under environmentally-relevant conditions. A comparison of solid phase to aqueous Na, Ca, S and Mg concentrations showed they were highly leachable in the materials. Given that the concentrations of these elements can affect plant community structure, it is important to understand their leachability and mobility as they migrate between materials used to construct the system. To that end, a mass balance of aqueous Na, Ca, S and Mg was conducted based on leaching experiments and materials analysis coupled with existing data from the constructed system. The data indicate that there is a large pool of leachable Na, Ca, S and Mg in the system, estimated at 27 t of Na, 14 t of Ca, 37.3 t of S and 8.8 t of Mg. Since recharge mainly drives the fen-upland system water regime, and discharge in the fen, evapo-accumulation of these solutes on the surface may occur.
Mostrar más [+] Menos [-]Pentachlorophenol from an old henhouse as a dioxin source in eggs and related human exposure Texto completo
2016
Piskorska-Pliszczynska, Jadwiga | Strucinski, Pawel | Mikolajczyk, Szczepan | Maszewski, Sebastian | Rachubik, Jaroslaw | Pajurek, Marek
High levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were detected in free-range eggs, and these levels reached a concentration of 29.84 ± 7.45 pg of WHO-TEQ/g of fat. This value exceeded the EU maximum permitted level of 2.5 pg of WHO-TEQ/g of fat for PCDD/F congeners by twelve-fold. A chemical analysis (HRGC-HRMS) revealed elevated amounts of OCDD, OCDF, HxCDD, HpCDD and HpCDF. During the investigation, samples of feed, soil, wall scrapings, wooden ceiling of the henhouse and tissues from laying hens were examined for dioxin contents (30 samples altogether). The long and complicated investigation found that the source of dioxins in the poultry farm was pentachlorophenol-treated wood, which was used as structural components in the 40-year-old farm building adapted to a henhouse. The wooden building material contained PCDD/Fs at a concentration of 3922.60 ± 560.93 pg of WHO-TEQ/g and 11.0 ± 2.8 μg/kg of PCP. The potential risk associated with dioxin intake was characterized by comparing the theoretically calculated weekly and monthly intakes with the toxicological reference values (TRVs), namely the Tolerable Weekly Intake (TWI) and Provisional Tolerable Monthly Intake (PTMI) values of 14 pg of WHO-TEQ/kg of bw and 70 pg of WHO-TEQ/kg of bw, respectively. The intake of dioxins estimated for high egg consumers (approximately 5–6 eggs/week) exceeded the TWI and PTMI values, which may pose a risk of delayed adverse health effects. The estimated dose of PCDD/Fs and DL-PCBs for children consuming 5 eggs per week exceeded the TWI by as much as 450% because of their nearly 5-fold-lower body weight. Although the dioxin intake estimated for the average consumption of eggs in the general population did not exceed any of the TRVs applied (58.7% TWI and 51.1% PTMI), such a situation should be considered unacceptable from a public health perspective because eggs are not the only source of these contaminants.
Mostrar más [+] Menos [-]Quality of roof-harvested rainwater – Comparison of different roofing materials Texto completo
2012
Lee, Ju Young | Bak, Gippeum | Han, Mooyoung
The objective of the study reported in this paper was to assess the quality of harvested rainwater on the basis of the roofing materials used and the presence of lichens/mosses on the roofing surface. Four pilot structures with different roofing materials (i.e., wooden shingle tiles, concrete tiles, clay tiles [Gi-Wa] and galvanized steel) were installed in a field. The galvanized steel was found to be the most suitable for rainwater harvesting applications, with their resulting physical and chemical water quality parameters meeting the Korean guidelines for drinking water quality (e.g., pH (5.8–8.5), TSS <500 mg/L, NO₃ ⁻ < 10 mg/L, SO₄ ²⁻ < 200 mg/L, Al < 0.2 mg/L, Cu < 1 mg/L, Fe < 0.3 mg/L, Pb < 0.05 mg/L, Zn < 1 mg/L, and E. coli (No detection)). In the galvanized steel case, the relatively high water quality was probably due to ultraviolet light and the high temperature effectively disinfecting the harvested rainwater. It was also found that the presence of lichens and mosses may adversely affect the physical, chemical and microbiological quality of rainwater.
Mostrar más [+] Menos [-]Hydrogen fluoride damage to vegetation from peri-urban brick kilns in Asia: A growing but unrecognised problem? Texto completo
2012
Ahmad, Muhammad Nauman | van den Berg, Leon J.L. | Shah, Hamid Ullah | Masood, Tariq | Büker, Patrick | Emberson, Lisa | Ashmore, Mike
The rapid urbanisation of many cities in south and south-east Asia has increased the demand for bricks, which are typically supplied from brick kilns in peri-urban areas. We report visible foliar damage to mango, apricot and plum trees in the vicinity of traditional Bull’s Trench brick kilns in Peshawar, Pakistan. Visible injury symptoms, hydrogen fluoride concentrations in air, and foliar fluoride concentrations were all greater in the vicinity of brick kilns than at more distant sites, indicating that fluoride emissions from brick kilns were the main cause of damage. Interviews with local farmers established the significant impact of this damage on their livelihoods. Since poorly regulated brick kilns are often found close to important peri-urban agricultural areas, we suggest that this may be a growing but unrecognised environmental problem in regions of Asia where emission control in brick kilns has not been improved.
Mostrar más [+] Menos [-]Pedogenesis, geochemical forms of heavy metals, and artifact weathering in an urban soil chronosequence, Detroit, Michigan Texto completo
2011
Howard, Jeffrey L. | Olszewska, Dorota
An urban soil chronosequence in downtown Detroit, MI was studied to determine the effects of time on pedogenesis and heavy metal sequestration. The soils developed in fill derived from mixed sandy and clayey diamicton parent materials on a level late Pleistocene lakebed plain under grass vegetation in a humid-temperate (mesic) climate. The chronosequence is comprised of soils in vacant lots (12 and 44 years old) and parks (96 and 120 years old), all located within 100m of a roadway. An A-horizon 16cm thick with 2% organic matter has developed after only 12 years of pedogenesis. The 12 year-old soil shows accelerated weathering of iron (e.g. nails) and cement artifacts attributed to corrosion by excess soluble salts of uncertain origin. Carbonate and Fe-oxide are immobilizing agents for heavy metals, hence it is recommended that drywall, plaster, cement and iron artifacts be left in soils at brownfield sites for their ameliorating effects.
Mostrar más [+] Menos [-]Painted surfaces - Important sources of polychlorinated biphenyls (PCBs) contamination to the urban and marine environment Texto completo
2009
Jartun, Morten | Ottesen, Rolf Tore | Steinnes, Eiliv | Volden, Tore
A study of a large number of samples of flaking old paint from various buildings in Bergen, Norway (N = 68) suggests that paint may be the most important contemporary source of PCBs in this urban environment with concentrations of PCB7 up to 3.39 g/kg. Twenty-three of the samples were collected from a single building, and the concentrations were found to vary over 3 orders of magnitude. In addition, 16 concrete samples from a large bridge previously coated with PCB-containing paint were collected and separated into outer- and inner samples indicating that PCBs are still present in high concentrations subsequent to renovation. PCBs were found in several categories of paint from wooden and concrete buildings, potentially introduced to the environment by natural weathering, renovation, and volatilization. Consequently, this dispersion may lead to increased levels of PCBs in urban atmospheres, soils, and harbor sediments where high concentrations have resulted in Governmental advice against consumption of certain seafood. Paint from structures built during the period 1950-1970 may be the most important source of PCBs in an urban environment.
Mostrar más [+] Menos [-]Synthetic TiO2 nanoparticle emission from exterior facades into the aquatic environment Texto completo
2008
Kaegi, R. | Ulrich, A. | Sinnet, B. | Vonbank, R. | Wichser, A. | Zuleeg, S. | Simmler, H. | Brunner, S. | Vonmont, H. | Burkhardt, M. | Boller, M.
We present direct evidence of the release of synthetic nanoparticles from urban applications into the aquatic environment. We investigated TiO2 particles as these particles are used in large quantities in exterior paints as whitening pigments and are to some extent also present in the nano-size range. TiO2 particles were traced from exterior facade paints to the discharge into surface waters. We used a centrifugation based sample preparation which recovers TiO2 particles between roughly 20 and 300 nm. Analytical electron microscopy revealed that TiO2 particles are detached from new and aged facade paints by natural weather conditions and are then transported by facade runoff and are discharged into natural, receiving waters. Microscopic investigations are confirmed by bulk chemical analysis. By combining results from microscopic investigations with bulk chemical analysis we calculated the number densities of synthetic TiO2 particles in the runoff. The release of synthetic TiO2 particles from exterior applications into the aquatic environment is demonstrated.
Mostrar más [+] Menos [-]Numerical analysis and modeling of two-loop experimental setup for measurements of radon diffusion rate through building and insulation materials Texto completo
2020
Szajerski, Piotr | Zimny, Arkadiusz
Radon is a natural radioactive gas present in the environment, which is considered as the second most important lung cancer cause worldwide. Currently, radon gas is under focus and was classified as contaminant of emerging concern, which is responsible for serious biological/health effects in human. In presented work we propose the numerical model and analysis method for radon diffusion rate measurements and radon transport parameters determination. The experimental setup for radon diffusion was built in a classical, two chamber configuration, in which the radon source and outlet reservoirs are separated by the sample being tested. The main difference with previously known systems is utilization of only one radon detector, what was achieved by a careful characterization of the Rn-222 source and development of a numerical model, which allows for exact determination of radon transport parameters by fitting simulated radon concentration profile in the outlet reservoir to experimental data. For verification of the developed system, several insulation materials commonly used in building industry and civil engineering, as well as, common building materials (gypsum, hardened cement paste, concrete) were tested for radon diffusion rate through these barriers. The results of radon transmittance, permeability and diffusion coefficients for investigated materials are in compliance with values known previously from the literature. The analysis method is fast and efficient, and requires measurement period varying from a dozen or so hours up to 2–3 days depending on material properties. The described method is entirely based on a numerical analysis of the proposed differential equation model using freely available SCILAB software and experimental data obtained during sample measurements.
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