scholarly journals Evaluation of Alternative Annular Denuder Systems for the Collection of Fine Aerosol Particulate Matter

2020 ◽  
Vol 2 (1) ◽  
pp. 96-110
Author(s):  
Spencer ◽  
Osborne ◽  
Van Heyst
Keyword(s):  
Particulate Matter ◽  
Environmental Protection Agency ◽  
Particle Deposition ◽  
Inorganic Aerosols ◽  
Filter Pack ◽  
Fine Aerosol ◽  
The Us ◽  
In Series ◽  
Us Epa ◽  
Annular Denuder

Due to the complex manner in which secondary inorganic aerosols (SIAs) form, a need exists to develop a methodology to measure PM2.5 emissions from agricultural operations to better understand the contribution of SIAs to the PM2.5 fraction. When sampling particulate matter (PM), annular denuder systems (ADS) are a United States Environmental Protection Agency (US EPA) approved system used to measure both gaseous and particulate components of aerosols. While collecting basic gases, such as ammonia, using nine denuders was feasibly demonstrated in poultry housing units but the ability of additional denuders to accurately collect the SIAs on the filters is yet to be demonstrated. An experiment was designed to assess particle deposition behaviors throughout three different ADS configurations. It was determined that the nine denuder configuration resulted in particles being impacted and retained, mainly in the U-bend junctions, prior to reaching the filters with only 87.2% of PM2.5 reaching the filter pack. The US EPA-prescribed ADS configuration had 99.4% of PM2.5 reaching the filters, indicating that there is an impact due to the U-Bend addition to the system. It was further demonstrated that having additional denuders in series with no U-Bend had no significant impact on PM2.5 deposition on the filters with 98.9% of PM2.5 being collected.

scholarly journals Simulation of a biogas cleaning process using different amines

2018 ◽  
Vol 27 (47) ◽  
Author(s):  
Guillermo Sepúlveda ◽  
Luis Eduardo Jaimes ◽  
Leonardo Pacheco ◽  
Carlos Alirio Díaz
Keyword(s):  
Environmental Protection Agency ◽  
Landfill Gas ◽  
Cleaning Process ◽  
Fuel Gas ◽  
Combustion Properties ◽  
The Us ◽  
Us Epa ◽  
Combustible Gases ◽  
Combustion Processes ◽  
Landfill Gas Emissions

The use of biogas generated in landfills has gained importance in developing countries like Colombia. Taking into account that this biogas presents poor combustion properties that make interchangeability with other combustible gases difficult, the elimination of gases and vapors, such as CO2 and H2O, through a cleaning process, in which the biogas is converted to biomethane, improves the biogas properties as a fuel gas for general use. In this work, we simulated the generation of biogas at El Carrasco sanitary landfill in Bucaramanga, using the US EPA (United States Environmental Protection Agency) landfill gas emissions model. Additionally, we simulated the biogas cleaning process to extract the remaining moisture using the ProMax software; for this, we used three different amines (MDEA, MEA, and DEA), followed by a glycol dehydration process. The results showed that the amine MEA produced the largest increase in the concentration of CH4 (90.37 %) for the biogas generated in the landfill. Furthermore, dehydration with glycol was an efficient process to obtain a gas with a high percentage of methane (91.47 %) and low water presence (1.27 %); this would allow the use of biomethane in conventional industrial combustion processes and power generation.

scholarly journals Geochemical Behavior of Uranium and Radon in Groundwater of Jurassic Granite Area, Icheon, Middle Korea

Water ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1278 ◽  
Author(s):  
Byong Wook Cho ◽  
Chang Oh Choo
Keyword(s):  
Standard Deviation ◽  
Environmental Protection Agency ◽  
Maximum Contaminant Level ◽  
Contaminant Level ◽  
Low Concentrations ◽  
Wide Range ◽  
The Us ◽  
Us Epa ◽  
Independent Behavior ◽  
Radon Concentrations

Uranium concentrations (a total of 82 samples) in groundwater in Icheon, middle Korea, showed a wide range from 0.02 to 1640 μg/L with a mean of 56.77 μg/L, a median of 3.03 μg/L, and a standard deviation of 228.63 μg/L. Most groundwater samples had quite low concentrations: 32.9% were below 1 μg/L, while 15.9% exceeded 30 μg/L, the maximum contaminant level (MCL) of the US EPA (Environmental Protection Agency). Radon concentrations also ranged widely from 1.48 to 865.8 Bq/L. Although the standard deviation of radon was large (151.8 Bq/L), the mean was 211.29 Bq/L and the median was 176.86 Bq/L. Overall, 64.6% of the samples exceeded the alternative maximum contaminant level (AMCL) of the US EPA (148 Bq/L). According to statistical analyses, there was no close correlations between uranium and radon, but there were correlations between uranium and redox potential (Eh) (−0.54), dissolved oxygen (DO) (−0.50), HCO3− (0.45), Sr (0.65), and SiO2 (−0.44). Radon showed independent behavior with respect to most components in groundwater. Uranium concentrations in groundwater increased with increasing water–rock interactions. Anomalously high uranium and radon concentrations in groundwater are preferentially localized in granite areas and spatial distributions are remarkably heterogeneous.

scholarly journals An assessment of the performance of the Monitor for AeRosols and GAses in ambient air (MARGA): a semi-continuous method for soluble compounds

2014 ◽  
Vol 14 (11) ◽  
pp. 5639-5658 ◽  
Author(s):  
I. C. Rumsey ◽  
K. A. Cowen ◽  
J. T. Walker ◽  
T. J. Kelly ◽  
E. A. Hanft ◽  
...  
Keyword(s):  
Linear Regression ◽  
Ambient Air ◽  
Water Soluble ◽  
Performance Goal ◽  
Filter Pack ◽  
Accuracy And Precision ◽  
The Us ◽  
Us Epa ◽  
Best Fit ◽  
A Performance

Abstract. Ambient air monitoring as part of the US Environmental Protection Agency's (US EPA's) Clean Air Status and Trends Network (CASTNet) currently uses filter packs to measure weekly integrated concentrations. The US EPA is interested in supplementing CASTNet with semi-continuous monitoring systems at select sites to characterize atmospheric chemistry and deposition of nitrogen and sulfur compounds at higher time resolution than the filter pack. The Monitor for AeRosols and GAses in ambient air (MARGA) measures water-soluble gases and aerosols at an hourly temporal resolution. The performance of the MARGA was assessed under the US EPA Environmental Technology Verification (ETV) program. The assessment was conducted in Research Triangle Park, North Carolina, from 8 September to 8 October 2010 and focused on gaseous SO2, HNO3, and NH3 and aerosol SO42-, NO3-, and NH4+. Precision of the MARGA was evaluated by calculating the median absolute relative percent difference (MARPD) between paired hourly results from duplicate MARGA units (MUs), with a performance goal of ≤ 25%. The accuracy of the MARGA was evaluated by calculating the MARPD for each MU relative to the average of the duplicate denuder/filter pack concentrations, with a performance goal of ≤ 40%. Accuracy was also evaluated by using linear regression, where MU concentrations were plotted against the average of the duplicate denuder/filter pack concentrations. From this, a linear least squares line of best fit was applied. The goal was for the slope of the line of best fit to be between 0.8 and 1.2. The MARGA performed well in comparison to the denuder/filter pack for SO2, SO42−, and NH4+, with all three compounds passing the accuracy and precision goals by a significant margin. The performance of the MARGA in measuring NO3- could not be evaluated due to the different sampling efficiency of coarse NO3- by the MUs and the filter pack. Estimates of "fine" NO3- were calculated for the MUs and the filter pack. Using this and results from a previous study, it is concluded that if the MUs and the filter pack were sampling the same particle size, the MUs would have good agreement in terms of precision and accuracy. The MARGA performed moderately well in measuring HNO3 and NH3, though neither met the linear regression slope goals. However, recommendations for improving the measurement of HNO3 and NH3 are discussed. It is concluded that SO42-, SO2, NO3-, HNO3, NH4+, and NH3 concentrations can be measured with acceptable accuracy and precision when the MARGA is operated in conjunction with the recommendations outlined in the manuscript.

scholarly journals Principles and techniques towards successful development of enzyme-linked immunosorbent assay (ELISA) for dioxin analysis

2021 ◽  
Author(s):  
Wei Zhang
Keyword(s):  
Immunosorbent Assay ◽  
Environmental Protection Agency ◽  
High Resolution Mass Spectrometry ◽  
Enzyme Linked Immunosorbent Assay ◽  
Environmental Matrices ◽  
Successful Development ◽  
Trace Level ◽  
The Us ◽  
Us Epa ◽  
Technical Details

Dioxins are highly toxic, persistent and bio-accumulative compounds. Laboratory detection of dioxins in various environmental matrices is one of the most technically demanding and expensive tasks in analytical chemistry.The cost to analyze a soil sample by conventional gas chromatography-high resolution mass spectrometry (GC-HRMS) is approximately $1,900 USC accordign to the Unisted States Environmental Protection Agency (US EPA) (Billets, 2005). As an alternative, enzyme-linked immunosorbent assay (ELISA) for dioxin analysis has been commercially available for over a decade and recognized as the US EPA Method 3025. However, assay attributes need to be examined, especially at trace level detection. In this study, sources of error in ELISA, such as background contamination and dioxin-like polycholrinated biphenyl (dl-BCB) cross-reactions have been investigated. Quality assurance data on spikes have been reviewed and the recovery was estimated to be 70%. Technical details that are crucial for the performance of dioxin in ELISA were also identified and addressed.

Removal of As, Cr and Cd by Absorptive Filtration

2013 ◽  
Vol 6 (1) ◽  
pp. 73-80 ◽  
Keyword(s):  
Environmental Protection Agency ◽  
Batch Adsorption ◽  
Solution Ph ◽  
Sand Filters ◽  
Bench Scale ◽  
Sand Surface ◽  
Iron Solution ◽  
The Us ◽  
Naoh Solution ◽  
In Series

The US Environmental Protection Agency (USEPA) recently introduced more stringent arsenic regulations by lowering the maximum contaminant level (MCL) to 10 ìg l-1 (ppb) arsenic in drinking water. During the present study, an iron solution injection sand filtration process was designed and tested to selectively remove arsenic (As(V)), chromate (Cr(VI)) and cadmium (Cd(II)) from aqueous solutions down to trace level. Bench scale sand columns with a chemical feeding system were used to conduct the filtration study. The filtration results demonstrate that As(V) could be removed by ferric solution-treated sand filters from 2,000 ìg l-1 (ppb) down to less than 5 ìg l-1 (ppb) using two sand filters connected in series (two stage filtration). During the filtration, ferric concentrations in the first and second filters were maintained at 5 and 2 ppm, respectively, through a continuous injection scheme. Bench scale filtration results suggest that Cr(VI) could also be effectively removed by injection of ferrous solution into the sand columns. Similar ferric treatment of the sand columns also significantly increased Cd(II) removal. Batch adsorption experimental results suggest that when solution pH is lower than 8, arsenate can be removed by iron-treated sand. Arsenate-saturated sand can be regenerated using a high pH (pH > 12) solution. Scanning Electron Microscope (SEM) and energy dispersive x-ray (EDX) studies suggest that very little amount of Fe on the sand surface was dissolved when the sand was regenerated using a dilute NaOH solution (pH = 13).

Trans-Epithelial Exposure Model (TEEM) - Epithelial Cells and Fibroblasts

2020 ◽  
Author(s):  
Shaun D. McCullough
Keyword(s):  
Particulate Matter ◽  
Epithelial Cells ◽  
Cell Line ◽  
Environmental Protection Agency ◽  
Airway Epithelium ◽  
Exposure Model ◽  
Protection Agency ◽  
The Us ◽  
Trade Names

Abstract This exposure model is meant to serve as an in vitro representation of trans-epithelial effects of airway diesel and particulate matter exposures on fibroblasts in the stroma. The epithelial cells in the airway epithelium are represented by 16HBE cells and the fibroblasts are represented by either the IMR90 cell line or primary fibroblasts.Disclaimer: The contents of this article have been reviewed by the US Environmental Protection Agency and approved for publication and do not necessarily represent Agency policy. Mention of trade names or commercial products does not constitute endorsement or recommendations for use.

Sludge disposal: ethics and expediency

2000 ◽  
Vol 42 (9) ◽  
pp. 1-5 ◽  
Author(s):  
P. A. Vesilind
Keyword(s):  
Environmental Protection Agency ◽  
Wastewater Treatment Plants ◽  
Health Effect ◽  
Health Protection ◽  
Wastewater Sludge ◽  
Worst Case ◽  
Regulatory Decision ◽  
Sludge Disposal ◽  
The Us ◽  
Us Epa

The United State Environmental Protection Agency (U.S. EPA) attempted to set health-based regulations for sludge disposal and used worst-case scenarios to estimate the detrimental health effect. In the absence of adequate information, this exercise led them to err so much on the conservative side that the regulations became unrealistic and would not have been accepted by the public. So the US EPA decided to do what was expedient – to establish regulations that allow most wastewater treatment plants to dispose of their sludges, knowing that these regulations are better than none at all. Such regulatory decision-making has ethical ramifications because it involves distributing costs and benefits between affected citizens. The principle of expediency as articulated by Earle Phelps calls for a regulator to optimize the benefits of health protection while minimizing costs within the constraints of technical feasibility. Phelps' expediency principle, proposed over fifty years ago, is still a useful application of ethics using scientific knowledge to set dynamic and yet enforceable environmental regulations. In the case of sludge disposal, the US EPA made an ethical decision based on the principle of expediency, weighing the moral good of human health protection versus the moral harm of taking wealth by requiring costly wastewater sludge treatment and disposal.

scholarly journals Principles and techniques towards successful development of enzyme-linked immunosorbent assay (ELISA) for dioxin analysis

2021 ◽  
Author(s):  
Wei Zhang
Keyword(s):  
Immunosorbent Assay ◽  
Environmental Protection Agency ◽  
High Resolution Mass Spectrometry ◽  
Enzyme Linked Immunosorbent Assay ◽  
Environmental Matrices ◽  
Successful Development ◽  
Trace Level ◽  
The Us ◽  
Us Epa ◽  
Technical Details

Dioxins are highly toxic, persistent and bio-accumulative compounds. Laboratory detection of dioxins in various environmental matrices is one of the most technically demanding and expensive tasks in analytical chemistry.The cost to analyze a soil sample by conventional gas chromatography-high resolution mass spectrometry (GC-HRMS) is approximately $1,900 USC accordign to the Unisted States Environmental Protection Agency (US EPA) (Billets, 2005). As an alternative, enzyme-linked immunosorbent assay (ELISA) for dioxin analysis has been commercially available for over a decade and recognized as the US EPA Method 3025. However, assay attributes need to be examined, especially at trace level detection. In this study, sources of error in ELISA, such as background contamination and dioxin-like polycholrinated biphenyl (dl-BCB) cross-reactions have been investigated. Quality assurance data on spikes have been reviewed and the recovery was estimated to be 70%. Technical details that are crucial for the performance of dioxin in ELISA were also identified and addressed.

scholarly journals Geochemical Assessment of Trace Metal Distribution and Contamination in the Surface Sediments of the Coast of Okinawa Island, Japan

2016 ◽  
Vol 6 (1) ◽  
pp. 1
Author(s):  
Ibrahima M'Bemba Diallo ◽  
Hiroaki Ishiga
Keyword(s):  
Environmental Protection Agency ◽  
Surface Sediments ◽  
Sediment Quality ◽  
Contamination Factor ◽  
Sediment Quality Guideline ◽  
Okinawa Island ◽  
X Ray ◽  
The Us ◽  
Quality Guideline ◽  
Us Epa

In this study, sediment samples were collected from the Awase tidal, the Minamigusuku, and Nakagusuku areas located in the Okinawa Island. The collected samples were analyzed using X-ray fluorescence to determine their geochemical compositions and distribution, and to assess the sediment quality in the study areas. Contamination factor (CF), geoaccumulation index (Igeo), and the United State Environmental Protection Agency Sediment Quality Guideline (US EPA SQG) were used to assess the sediment quality. The results show that the highest average concentrations of As (11mg/kg), Pb (8 mg/kg), Zn (19 mg/kg), Cu (6 mg/kg), and Cr (14mg/kg) occurred in the Minamigusuku area. The CF and Igeo values, and the US EPA SQG indicate that among the selected trace metals only As displays significant values in the study areas. The CF values of As in the Minamigusuku area show moderate enrichment, and in this same area, the Igeo values of As present significant values, ranging from moderate to considerable contaminations, implying a possible effect on the biota in this location. Compared to the US EPA SQG, the Awase tidal flat and Nakagusuku areas are moderately polluted, whereas Minamigusuku is heavily polluted, suggesting that As may possible impact the biota in these areas. Consequently, for a better sustainable development of the coast of  Okinawa Island , a regular monitoring and assessment of study areas, particularly the Minamigusuku area, is necessary to determine over time the concentration of As.

scholarly journals An assessment of the performance of the Monitor for AeRosols and GAses in ambient air (MARGA): a semi-continuous method for soluble compounds

2013 ◽  
Vol 13 (9) ◽  
pp. 25067-25124 ◽  
Author(s):  
I. C. Rumsey ◽  
K. A. Cowen ◽  
J. T. Walker ◽  
T. J. Kelly ◽  
E. A. Hanft ◽  
...  
Keyword(s):  
Linear Regression ◽  
Ambient Air ◽  
Performance Goal ◽  
Filter Pack ◽  
Accuracy And Precision ◽  
The Us ◽  
Percent Difference ◽  
Relative Percent Difference ◽  
Us Epa ◽  
Best Fit

Abstract. Ambient air monitoring as part of the US Environmental Protection Agency's (US EPA's) Clean Air Status and Trends Network (CASTNet) currently uses filter packs to measure weekly integrated concentrations. The US EPA is interested in supplementing CASTNet with semi-continuous monitoring systems at select sites to characterize atmospheric chemistry and deposition of nitrogen and sulfur compounds at higher time resolution than the filter pack. The Monitor for AeRosols and GAses in ambient air (MARGA) measures water-soluble gases and aerosols at hourly temporal resolution. The performance of the MARGA was assessed under the US EPA Environmental Technology Verification (ETV) program. The assessment was conducted in Research Triangle Park, North Carolina from 8 September–8 October 2010 and focused on gaseous SO2, HNO3 and NH3 and aerosol SO4−, NO3− and NH4+. Precision of the MARGA was evaluated by calculating the median absolute relative percent difference (MARPD) between paired hourly results from duplicate MARGA units (MUs), with a performance goal of <25%. The accuracy of the MARGA was evaluated by calculating the median absolute relative percent difference (MARPD) for each MU relative to the average of the duplicate denuder/filter pack concentrations, with a performance goal of ≤40%. Accuracy was also evaluated by using linear regression, where MU concentrations were plotted against the average of the duplicate denuder/filter pack concentrations. From this, a linear least squares line of best fit was applied. The goal was for the slope of the line of best fit to be between 0.8 and 1.2. The MARGA performed well in comparison to the denuder/filter pack for SO2, SO42− and NH4+, with all three compounds passing the accuracy and precision goals by a significant margin. The performance of the MARGA in measuring NO3− could not be evaluated due to the different sampling efficiency of coarse NO3− by the MUs and the filter pack. Estimates of "fine" NO3− were calculated for the MUs and the filter pack. Using this and results from a previous study, it is concluded that if the MUs and the filter pack were sampling the same particle size, the MUs would have good agreement in terms of precision and accuracy. The MARGA performed moderately well in measuring HNO3 and NH3, though neither met the linear regression slope goals. However, recommendations for improving the measurement of HNO3 and NH3 are discussed. It is concluded that SO42−, SO2, NO3−, HNO3, NH4+ and NH3 concentrations can be measured with acceptable accuracy and precision when the MARGA is operated in conjunction with the recommendations outlined in the manuscript.

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