scholarly journals Occurrence of Cryptosporidium oocysts in US wastewaters

2006 ◽  
Vol 4 (4) ◽  
pp. 437-452 ◽  
Author(s):  
Randi M. McCuin ◽  
Jennifer L. Clancy
Keyword(s):  
Internal Control ◽  
Secondary Effluent ◽  
Method Performance ◽  
The Us ◽  
Secondary Effluents ◽  
Cryptosporidium Oocysts ◽  
Wastewater Samples ◽  
Gamma Irradiated ◽  
Red Dye ◽  
Texas Red

Wastewater samples collected from ten wastewater facilities across the US were analyzed to determine the occurrence of indigenous Cryptosporidium oocysts using methods based on modifications of USEPA Method 1622. Wastewater facilities participating in this study ranged in size from 0.6 to 193 mgd average daily flow. A total of 289 wastewater samples were analyzed over a 15-month period. ColorSeed is a commercial product containing gamma-irradiated Cryptosporidium oocysts that have been permanently stained with a Texas Red dye. ColorSeed was used as an internal control with each sample to assess method performance. In 500 ml sample volumes, mean ColorSeed recoveries in raw influents and primary effluents were 26.1±17.7% and 33.0±17.9%, respectively. In 10 liter volumes of secondary effluent, mean ColorSeed recovery was 25.0±16.6%. Volumes analyzed for tertiary effluent samples ranged from 14.8 l to 131.3 l resulting in a mean ColorSeed recovery of 48.8±14.5%. Indigenous oocysts were detected in 30% of raw influents, 46% of primary effluents, 58% of secondary effluents and 19% of tertiary effluents analyzed. Indigenous oocyst concentrations ranged from <2 to 86 /liter across all wastewater matrices tested.

scholarly journals Development of a Method for Detection of Giardia duodenalis Cysts on Lettuce and for Simultaneous Analysis of Salad Products for the Presence of Giardia Cysts and Cryptosporidium Oocysts

2007 ◽  
Vol 73 (22) ◽  
pp. 7388-7391 ◽  
Author(s):  
N. Cook ◽  
R. A. B. Nichols ◽  
N. Wilkinson ◽  
C. A. Paton ◽  
K. Barker ◽  
...  
Keyword(s):  
Internal Control ◽  
Giardia Duodenalis ◽  
Immunomagnetic Separation ◽  
Internal Controls ◽  
Food Sample ◽  
Simultaneous Analysis ◽  
Natural Food ◽  
Cryptosporidium Oocysts ◽  
Natural Foods ◽  
Texas Red

ABSTRACT We report a method for detecting Giardia duodenalis cysts on lettuce, which we subsequently use to examine salad products for the presence of Giardia cysts and Cryptosporidium oocysts. The method is based on four basic steps: extraction of cysts from the foodstuffs, concentration of the extract and separation of the cysts from food materials, staining of the cysts to allow their visualization, and identification of cysts by microscopy. The concentration and separation steps are performed by centrifugation, followed by immunomagnetic separation using proprietary kits. Cyst staining is also performed using proprietary reagents. The method recovered 46.0% ± 19.0% (n = 30) of artificially contaminating cysts in 30 g of lettuce. We tested the method on a variety of commercially available natural foods, which we also seeded with a commercially available internal control, immediately prior to concentration of the extract. Recoveries of the Texas Red-stained Giardia cyst and Cryptosporidium oocyst internal controls were 36.5% ± 14.3% and 36.2% ± 19.7% (n = 20), respectively. One natural food sample of organic watercress, spinach, and rocket salad contained one Giardia cyst 50 g−1 of sample as an indigenous surface contaminant.

scholarly journals Occurrence of SARS-CoV-2 RNA in Six Municipal Wastewater Treatment Plants at the Early Stage of COVID-19 Pandemic in The United States

Pathogens ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 798
Author(s):  
Samendra P. Sherchan ◽  
Shalina Shahin ◽  
Jeenal Patel ◽  
Lauren M. Ward ◽  
Sarmila Tandukar ◽  
...  
Keyword(s):  
United States ◽  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Wastewater Treatment Plants ◽  
Quantitative Polymerase Chain Reaction ◽  
The United States ◽  
Secondary Effluent ◽  
Untreated Wastewater ◽  
Treatment Processes ◽  
Wastewater Samples

In this study, we investigated the occurrence of Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) RNA in primary influent (n = 42), secondary effluent (n = 24) and tertiary treated effluent (n = 34) collected from six wastewater treatment plants (WWTPs A–F) in Virginia (WWTP A), Florida (WWTPs B, C, and D), and Georgia (WWTPs E and F) in the United States during April–July 2020. Of the 100 wastewater samples analyzed, eight (19%) untreated wastewater samples collected from the primary influents contained SARS-CoV-2 RNA as measured by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) assays. SARS-CoV-2 RNA were detected in influent wastewater samples collected from WWTP A (Virginia), WWTPs E and F (Georgia) and WWTP D (Florida). Secondary and tertiary effluent samples were not positive for SARS-CoV-2 RNA indicating the treatment processes in these WWTPs potentially removed SARS-CoV-2 RNA during the secondary and tertiary treatment processes. However, further studies are needed to understand the log removal values (LRVs) and transmission risks of SARS-CoV-2 RNA through analyzing wastewater samples from a wider range of WWTPs.

scholarly journals Sulphate-Crosslinked Chitosan as an Adsorbent for the Removal of Congo Red Dye From Aqueous Solution

2018 ◽  
Vol 11 ◽  
pp. 117862211881168 ◽  
Author(s):  
Christine Jeyaseelan ◽  
Nisha Chaudhary ◽  
Ravin Jugade
Keyword(s):  
Adsorption Capacity ◽  
Congo Red ◽  
Water Bodies ◽  
X Ray ◽  
Modified Chitosan ◽  
Freundlich Adsorption Isotherm ◽  
Pseudo Second Order ◽  
Crosslinked Chitosan ◽  
Wastewater Samples ◽  
Red Dye

Dyes are a major cause of concern nowadays as large quantities are being released into water bodies causing pollution. In this article, modified chitosan (sulphate crosslinked) has been studied for the removal of Congo red (a benzidine-based anionic diazo dye) which is a toxic dye introduced into water bodies from textile industries. Sulphate-crosslinked chitosan (SCC) was prepared in the laboratory and the characterization of SCC was done by Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Various parameters such as pH, contact time, adsorbent dosage, and concentration of adsorbent were optimized. The adsorption capacity was determined at pH 3.0, at which the percentage recovery was about 90% and followed Freundlich adsorption isotherm with an adsorption capacity of 91.8 mg/g. The adsorption followed pseudo-second-order kinetics. Various thermodynamic parameters were also determined for the change in adsorption with temperature. The SCC was regenerated with NaOH and showed good recycling capacity. The modified chitosan was applied for the removal of Congo red from industrial wastewater samples (spiked).

Tertiary treatment of Berlin WWTP effluents with ferrate (Fe(VI))

2013 ◽  
Vol 68 (7) ◽  
pp. 1665-1671 ◽  
Author(s):  
U. Hübner ◽  
M. Jekel
Keyword(s):  
Surface Waters ◽  
Major Product ◽  
Advanced Treatment ◽  
Dual Function ◽  
Secondary Effluent ◽  
Tertiary Treatment ◽  
Efficient Removal ◽  
Promising Alternative ◽  
Secondary Effluents ◽  
The Eu

New and higher standards in the EU water framework directive necessitate advanced treatment of secondary effluents for reduction of trace organic compounds (TrOCs) and nutrients before the discharge into receiving surface waters. Due to its dual function as oxidant and coagulant, ferrate is considered as a promising alternative for tertiary treatment. The oxidation of selected TrOCs and simultaneous flocculation of phosphates by ferrate was tested in batch experiments with secondary effluent from Berlin Ruhleben. The concentrations of carbamazepine (CBZ) and diclofenac were reduced by >90% with ferrate dosages of 6 mg/L as Fe. CBZ was transformed to 1-(2-benzaldehyde)-4-hydro-(1H,3H)-quinazoline-2-one, which is known as the major product from the reaction of CBZ with ozone. In contrast to ozonation, no further transformation of this product was observed. The concentration of ibuprofen was not reduced by ferrate treatment. For efficient removal of 60–100 μg/L phosphate-P to values <20 μg/L, ferrate dosages of 3–4 mg/L as Fe were sufficient.

Influence of US EPA 1622 method successive steps on the viability of Cryptosporidium oocysts

2000 ◽  
Vol 41 (7) ◽  
pp. 189-196 ◽  
Author(s):  
K. Guyot ◽  
M. F. Gireaudot-Liepmann ◽  
A. Cabon ◽  
I. Riveau-Ricard ◽  
M. Lange ◽  
...  
Keyword(s):  
Water Samples ◽  
Tap Water ◽  
High Recovery ◽  
The Us ◽  
Cryptosporidium Oocysts ◽  
Cartridge Filter ◽  
Us Epa ◽  
Cryptosporidium Parvum Oocysts ◽  
Elution Step

Viable Cryptosporidium parvum oocysts were processed by the US EPA 1622 method to determine if the procedure that requires successive filtration, elutionand centrifugation alters their integrity and viability (determined by in vitro excystation). Oocyst seeded in tap water samples were also used to evaluate recovery efficiencies and impact of the whole procedure on oocyst viability. Filtration through Envirochek Gelman cartridge was found not to damage oocysts. The use of Laureth-12 buffer during the elution step was shown to lead to greater spontaneous oocysts excystation than other phosphate buffers containing between 80 and/or SDS (like the Gelman buffer). However, this drawback was widely balanced against the best efficiency of this buffer to elute oocysts captured by the cartridge filter and therefore against its high recovery efficiency. Thus, in water samples in which the oocyst concentration is expected to be low, it is more advantageous to employ the Laureth-12 buffer for the elution through it can influence viability. Centrifugation speeds (1,000–5,000 g) did not alter oocysts.

scholarly journals Influence of the Sarbanes-Oxley Act on Financial Reporting Quality: An Overview of EU Firms Cross-Listed in the USA

2021 ◽  
Author(s):  
Ujkan Bajra ◽  
Rrustem Asllanaj
Keyword(s):  
Financial Reporting ◽  
Internal Control ◽  
Reporting Quality ◽  
Financial Reporting Quality ◽  
Publicly Traded ◽  
Publicly Traded Companies ◽  
Sarbanes Oxley ◽  
Novel Approach ◽  
The Us ◽  
The Usa

Abstract This paper investigate whether compliance with the Sarbanes–Oxley Act of 2002 (SOX) Sect. 302 (financial reporting) and 404 (internal controls) enhances financial reporting quality (FRQ). This study focuses on EU publicly traded companies that are cross-listed in the US markets. Using a novel approach with respect to operationalization of the SOX, the empirical research integrated into this paper advances the understanding of financial reporting quality for both practitioners and policymakers. The study argues that financial reporting quality increased after SOX entered into force but, notably, we find that FRQ improves with compliance with SOX302 but not with SOX404. Examination of the latter relationship at the subsection level also reveals that compliance with certain SOX requirements is not satisfactory. We find that three out of six subsections of SOX302 are directly associated with financial reporting, while subsections (1), (5) and (6) of SOX302 are not related with FRQ, indicating that the management team, albeit not entirely, provides a reliable financial reporting systems. We also find that compliance with some SOX404’s subsections has been relatively low (i.e. subsections (1) and (3) of SOX404)), suggesting that corporations have not established and are not maintaining suitable internal control systems over financial reporting.

Whistleblowing in India: evidence from accounting students and professionals

2020 ◽  
Vol 28 (1) ◽  
pp. 126-146
Author(s):  
Richard G. Brody ◽  
Gaurav Gupta ◽  
Todd White
Keyword(s):  
Internal Control ◽  
Accounting Students ◽  
Western World ◽  
Accounting Ethics ◽  
Content Type ◽  
Accounting Professionals ◽  
The Us ◽  
English Speaking ◽  
Logistic Regressions ◽  
Univariate Analyses

Purpose The purpose of this paper is to examine whistleblowing behavior in the accounting community (students and professionals) in an emerging economy – India. Design/methodology/approach Using a case-based approach, data were collected from 263 accounting students and 268 accounting professionals in India. Findings Using multivariate and univariate analyses of variance and logistic regressions, the authors provided evidence on how accounting students and professionals behave in a whistleblowing environment. Specifically, the authors found mixed results when comparing the behavior of accounting students and professionals in a whistleblowing scenario. All subjects reflected a more collectivist attitude, although professionals were more concerned about “fixing” the identified internal control problem (a “shared” problem). Both groups expressed a firm desire to collect more evidence against the likely fraudster. Practical implications In this era of global offshoring of services including accounting, the current study makes significant contributions to the accounting ethics literature and the accounting profession by analyzing whistleblowing behavior from an Indian perspective – a highly underrepresented area in the accounting ethics literature. The study aims to guide companies and investors in the US and elsewhere that do business in India. Originality/value While the accounting literature has plenty of research on whistleblowing in the Western world, there is a dearth of literature on whistleblowing in India. This paper is among the first to document whistleblowing behavior in India, a country that prides itself on its vast availability of English-speaking and technically sound accounting professionals.

Genotoxicity of Organic Substances in Municipal Sewage and Its Ozonated Products

1992 ◽  
Vol 25 (11) ◽  
pp. 285-291 ◽  
Author(s):  
Y. Ono ◽  
I. Somiya ◽  
M. Kawamura ◽  
K. Uenishi
Keyword(s):  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Test System ◽  
Municipal Sewage ◽  
Secondary Effluent ◽  
Gel Chromatography ◽  
Organic Substances ◽  
Industrial Wastewaters ◽  
Umu Test ◽  
Secondary Effluents

Some organic substances contaminated in industrial wastewaters are not easily decomposed through biological treatment plant. In order to investigate the genotoxicity of the substances which remain in effluent from a municipal sewage treatment plant receiving industrial wastewaters, bacterial and mammalian assays were applied to the concentrated samples of secondary effluent. Ozonation was applied to decompose hard-biodegradable organic matters and to decrease its genotoxic intensity. Genotoxicity was surveyed for the concentrated samples using umu test system which can detect the umuDC genes that are known to cause error-prone repair. Positive results were observed in the case of Sep-pak-methanol extracts of secondary effluents with microsomal activation. Results of umu test showed negative in the ozonated samples of the effluent. Genotoxic substances in secondary effluents were decomposed by ozone into non-genotoxic substances. The concentrated sample was fractionated by gel chromatography using Sephadex LH-20 which can separate the molecule in the range from 100 to 5,000. A fraction of the effluent was determined as positive in umu test. The substances were detected in the range of over 5,000 molecular size.

scholarly journals Detection of Giardia and Cryptosporidium cysts/oocysts in watersheds and drinking water sources in Brazil urban areas

2009 ◽  
Vol 8 (2) ◽  
pp. 399-404 ◽  
Author(s):  
Maria Tereza Pepe Razzolini ◽  
Thaís Filomena da Silva Santos ◽  
Veridiana Karmann Bastos
Keyword(s):  
Drinking Water ◽  
Water Samples ◽  
Urban Areas ◽  
Water Sources ◽  
Raw Water ◽  
Protozoan Parasites ◽  
The Us ◽  
Cryptosporidium Oocysts ◽  
Us Epa ◽  
Giardia Cysts

The protozoan parasites Giardia and Cryptosporidium have been described as important waterborne disease pathogens, and are associated with severe gastrointestinal illnesses. The objective of this paper was to investigate the presence of Giardia cysts and Cryptosporidium oocysts in samples from watershed catchments and treated water sources. A total of 25 water samples were collected and examined according to the US EPA—Method 1623, 2005, consisting of 12 from drinking water and 13 from raw water. Positive samples from raw water for Giardia cysts and Cryptosporidium oocysts were 46.1 and 7.6%, respectively. In finished water, positive samples were 41.7% for Giardia cysts and 25.0% for Cryptosporidium oocysts. Concentrations of Giardia cysts found in raw water samples ranged from “not detected” to 3.4 cysts/L, whereas concentrations of Cryptoporidium oocysts ranged from “not detected” to 0.1 oocysts/L. In finished water, Giardia concentrations ranged from “not detected” to 0.06 cysts/L, and Cryptosporidium, from “not detected” to 0.01 oocysts/L. Concentrations of Giardia cysts and Cryptosporidium oocysts were not high in the samples analyzed. Nevertheless, the results of this study highlight the need to monitor these organisms in both raw and drinking water.

scholarly journals Tailing propensity in the ultraviolet disinfection of trickling filter and activated sludge wastewater treatment processes

2017 ◽  
Vol 76 (3) ◽  
pp. 623-632 ◽  
Author(s):  
Thiam C. Tan ◽  
Yaldah Azimi ◽  
Ramin R. Farnood
Keyword(s):  
Activated Sludge ◽  
Suspended Particle ◽  
Uv Disinfection ◽  
Distribution Data ◽  
Trickling Filter ◽  
Floc Size ◽  
Sludge Flocs ◽  
Filter System ◽  
Secondary Effluents ◽  
Wastewater Samples

In this paper, the effect of suspended flocs on the tailing of ultraviolet (UV) disinfection kinetics of secondary effluents was examined. To achieve this goal, final effluents produced in two processes for treating wastewater; namely, a trickling filter system and an activated sludge system, were collected and their UV disinfection were compared. Tailing of the UV dose response curve was controlled by the fraction of flocs that are both culturable and UV-resistant, referred to as the ‘tailing propensity’. Using this parameter, the contribution of various floc size fractions in reducing the UV disinfection efficiency of wastewater samples was quantified. Activated sludge flocs larger than 125 μm exhibited as much as 35 times greater tailing propensity than smaller flocs in the range of 20–25 μm. Within a fixed size range, the tailing propensity of flocs generated in the trickling filter system was 3 to 8 times higher than that of activated sludge flocs, and this difference increased with the floc size. A mathematical model was developed to predict the UV disinfection of secondary effluents from suspended particle size distribution data. The model showed good agreement with experimental results.

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