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1.
Water Environ Res ; 96(3): e11009, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38444297

RESUMEN

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are an emerging issue in wastewater treatment. High-temperature thermal processes, incineration being time-tested, offer the opportunity to destroy and change the composition of PFAS. The fate of PFAS has been documented through wastewater sludge incinerators, including a multiple hearth furnace (MHF) and a fluidized bed furnace (FBF). The dewatered wastewater sludge feedstock averaged 247- and 1280-µmol targeted PFAS per sample run in MHF and FBF feed, respectively. Stack emissions (reportable for all targeted PFAS from MHF only) averaged 5% of that value with shorter alkyl chain compounds comprising the majority of the targeted PFAS. Wet scrubber water streams accumulated nonpolar fluorinated organics from the furnace exhaust with an average of 0.740- and 0.114-mol F- per sample run, for the MHF and FBF, respectively. Simple alkane PFAS measured at the stack represented 0.5%-4.5% of the total estimated facility greenhouse gas emissions. PRACTITIONER POINTS: The MHF emitted six short chain PFAS from the stack, which were shorter alkyl chain compounds compared with sludge PFAS. The FBF did not consistently emit reportable PFAS from the stack, but contamination complicated the assessment. Five percent of the MHF sludge molar PFAS load was reported in the stack. MHF and FBF wet scrubber water streams accumulated nonpolar fluorinated organics from the furnace exhaust. Ultra-short volatile alkane PFAS measured at the stack represented 0.5%-4.5% of the estimated facility greenhouse gas emissions.


Asunto(s)
Fluorocarburos , Gases de Efecto Invernadero , Aguas del Alcantarillado , Aguas Residuales , Alcanos , Incineración , Agua
2.
Chemosphere ; 262: 127900, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32799152

RESUMEN

Sequencing batch reactors (SBRs) were operated for 36 days to simulate the potential wastewater treatment impacts as well as fate and transport of per- and polyfluoroalkyl substances (PFAS) that could be associated with a release of alcohol resistant aqueous film forming foam (AR-AFFF) from on-site methanol fire suppression systems. The results of this study indicate that two days of exposure to AFFF were associated with small reductions in mixed liquor solids content and nitrification rates. No impacts on denitrification or biological phosphorus removal were observed. The addition of AFFF was associated with increases in 6:2 fluorotelomer sulfonate (6:2 FTS) in influent, effluent, and solids samples in the SBR. The following biotransformation pathway is proposed: an unidentified fluorotelomer precursor quickly degraded to 6:2 FTS, which then slowly degraded to several identified degradation intermediates and terminal, short-chain perfluorocarboxylic acid products. Data for 6:2 FTS, which was used as a proxy for AFFF-associated PFAS, were extrapolated to estimate that a removal of approximately 70% of AFFF via effluent and solids wasting would occur after 4 days at a full-scale treatment plant. This information can be used to better understand potential impacts on downstream processes, including potable reuse and biosolids production.


Asunto(s)
Fluorocarburos/análisis , Eliminación de Residuos Líquidos , Aguas Residuales/química , Contaminantes Químicos del Agua/análisis , Biotransformación , Incendios , Agua
3.
J Microbiol Methods ; 178: 106068, 2020 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-32980335

RESUMEN

Collection System Investigation Microbial Source Tracking (CSI-MST) is a novel, sensitive approach for identifying sewer infrastructure deficiencies using molecular markers. This method requires both a detailed understanding of collection and conveyance system infrastructure and quickly turned around molecular data to advise an adaptive, targeted in-pipe approach to detect deficiencies. Here we explain the CSI-MST approach and provide several case study examples of how this approach can be adapted to different scale watersheds to identify potential sewer infrastructure issues. This approach has been used to locate and confirm the remediation of numerous needed infrastructure repairs in the southeastern Virginia region. The selected case studies presented here serve as a proof of concept-this methodology can be adopted by other utilities and municipalities to address necessary wastewater infrastructure repairs in different regions.

4.
Water Res ; 186: 116296, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32841929

RESUMEN

Wastewater-based epidemiology (WBE) has been used to analyze markers in wastewater treatment plant (WWTP) influent to characterize emerging chemicals, drug use patterns, or disease spread within communities. This approach can be particularly helpful in understanding outbreaks of disease like the novel Coronavirus disease-19 (COVID-19) when combined with clinical datasets. In this study, three RT-ddPCR assays (N1, N2, N3) were used to detect severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in weekly samples from nine WWTPs in southeastern Virginia. In the first several weeks of sampling, SARS-CoV-2 detections were sporadic. Frequency of detections and overall concentrations of RNA within samples increased from mid March into late July. During the twenty-one week study, SARS-CoV-2 concentrations ranged from 101 to 104 copies 100 mL-1 in samples where viral RNA was detected. Fluctuations in population normalized loading rates in several of the WWTP service areas agreed with known outbreaks during the study. Here we propose several ways that data can be presented spatially and temporally to be of greatest use to public health officials. As the COVID-19 pandemic wanes, it is likely that communities will see increased incidence of small, localized outbreaks. In these instances, WBE could be used as a pre-screening tool to better target clinical testing needs in communities with limited resources.


Asunto(s)
Infecciones por Coronavirus , Coronavirus , Pandemias , Neumonía Viral , Betacoronavirus , COVID-19 , Humanos , SARS-CoV-2 , Virginia/epidemiología , Monitoreo Epidemiológico Basado en Aguas Residuales
5.
Rev. peru. med. exp. salud publica ; 29(4): 469-476, oct.-dic. 2012. ilus, graf, mapas, tab
Artículo en Español | LILACS, LIPECS | ID: lil-662933

RESUMEN

Objetivos. Determinar la diversidad genética de aislamientos peruanos de Leptospira spp. mediante electroforesis en gel de campo pulsado (PFGE). Materiales y métodos. Se estandarizó la metodología de PFGE propuesta por Galloway y Levett (2008). Se elaboró una base de datos con los perfiles de PFGE de 65 cepas de referencia y se aplicó la técnica en 111 aislamientos de Leptospira spp. obtenidos en Perú entre 2002 y 2010. Resultados. Se determinó gran diversidad genética de serovares de Leptospira spp. circulantes en nuestro país. Se identificaron 57 serovares, 47 en 97 aislamientos patógenos. Los serovares más frecuentes fueron Icterohaemorrhagiae/Copenhageni (n=24) y Canicola (n=7). Las especies más frecuentes fueron L. santarosai (49,5%) y L. interrogans (37,1%). La distribución de especies, clusters y serovares varió según la fuente del aislamiento, el contexto ambiental y la procedencia. Conclusiones. Existe gran diversidad de serovares circulantes en el Perú, la cual está relacionada a la especie, el reservorio, el contexto ambiental y la procedencia del aislamiento. Se evidencia las relaciones genéticas y epidemiológicas entre aislamientos de diferentes fuentes, lo cual está relacionada a la especie, el reservorio, el contexto ambiental y la procedencia del aislamiento.


Objectives. Determine the genetic diversity of Peruvian isolations of Leptospira spp. through Pulsed Field Gel Electrophoresis (PFGE). Materials and methods. The PFGE methodology proposed by Galloway and Levett (2008) was standardized. A database including the PFGE profiles of 65 reference strains was prepared, and the technique was applied in 111 isolates of Leptospira spp. obtained in Peru between 2002 and 2010. Results. A great generic diversity of serovars of circulating Leptospira spp. was determined in our country. 57 serovars were identified, 47 out of 97 pathogen isolates. Most frequent serovars were Icterohaemorrhagiae/Copenhageni (n=24) and Canicola (n=7). The most frequent species were L. santarosai (49,5%) and L. interrogans (37,1%). The distribution of species, clusters and serovars changed according to the source of isolate, the environmental context and the origin. Conclusions. There is great diversity of circulating serovars in Peru. There are genetic and epidemiological relations among isolates of different sources, and this is related to species, reservoir, environmental context and the origin of the isolate.


Asunto(s)
Animales , Humanos , Variación Genética , Leptospira/genética , Electroforesis en Gel de Campo Pulsado , Leptospira/aislamiento & purificación , Perú
6.
Rev Peru Med Exp Salud Publica ; 29(4): 469-76, 2012.
Artículo en Español | MEDLINE | ID: mdl-23338631

RESUMEN

OBJECTIVES: Determine the genetic diversity of Peruvian isolations of Leptospira spp. through Pulsed Field Gel Electrophoresis (PFGE). MATERIALS AND METHODS: The PFGE methodology proposed by Galloway and Levett (2008) was standardized. A database including the PFGE profiles of 65 reference strains was prepared, and the technique was applied in 111 isolates of Leptospira spp. obtained in Peru between 2002 and 2010. RESULTS: A great generic diversity of serovars of circulating Leptospira spp. was determined in our country. 57 serovars were identified, 47 out of 97 pathogen isolates. Most frequent serovars were Icterohaemorrhagiae/Copenhageni (n=24) and Canicola (n=7). The most frequent species were L. santarosai (49,5%) and L. interrogans (37,1%). The distribution of species, clusters and serovars changed according to the source of isolate, the environmental context and the origin. CONCLUSIONS: There is great diversity of circulating serovars in Peru. There are genetic and epidemiological relations among isolates of different sources, and this is related to species, reservoir, environmental context and the origin of the isolate.


Asunto(s)
Variación Genética , Leptospira/genética , Animales , Electroforesis en Gel de Campo Pulsado , Humanos , Leptospira/aislamiento & purificación , Perú
8.
Rev. peru. med. exp. salud publica ; 26(4): 441-448, oct.-dic. 2009. ilus, tab, graf
Artículo en Español | LILACS, LIPECS | ID: lil-564535

RESUMEN

Objetivos. Determinar la magnitud de un brote y los factores asociados a la presencia de leptospirosis en la localidadde residencia de un menor de edad que presentó un cuadro de síndrome ictérico hemorrágico. Materiales y métodos.Fueron entrevistados y examinados niños y adolescentes de la zona de residencia del caso índice que frecuentaban unafuente común de infección entre los meses de enero y febrero del 2004. Se realizaron exámenes de ELISA IgM, MAT, PCR y cultivo para el diagnóstico de leptospirosis. Resultados. Fueron incluidos 77 sujetos entre 2 a 18 años de edad, siendo confirmados 21 casos (27,3 por ciento). Los signos y síntomas de los casos confirmados fueron fiebre, cefalea, mialgias, dolor abdominal, náusea, vómitos e hiporexia. Tres de ellos presentaron ictericia, hemorragia y falla renal. El análisis bivariado mostró que aquellos que estuvieron en contacto con la fuente de infección de agua clara (cristalina) tuvieron un OR=3,26(IC95 por ciento 1,22 a 8,72) y el contacto con perros en la fuente de agua un OR de 5,63 (IC95 por ciento 1,40 a 22,63). Conclusiones. Se confirmó un brote de leptospirosis dentro de un contexto epidemiológico nuevo relacionados a una fuente común de agua subterránea y asociada al contacto con perros dentro de esta fuente. Esta investigación permitirá ampliar el conocimiento acerca de esta patología, así como considerar la leptospirosis como causa de enfermedad febril aguda.


Objectives. Identify the frequency and risk factors of leptospirosis outbreak in the locality of residence of an index casewith icterohemorrhagic syndrome. Material and methods. Were interviewed and examined children and teenagers fromresidence area of index case who frequented a common source of infection between January and February, 2004. Allof them were screened for leptospirosis using IgM-ELISA and microscopic agglutination test (MAT), PCR and culture.Results. Were enrolled 77 subjects between 2 to 18 years old, only 21 (27.3 per cent) were confirmed cases. The signs and symptoms of the confirmed cases were fever, headache, myalgia, abdominal pain, nausea, vomiting and anorexia. Three of them presented with jaundice, bleeding and renal failure. The presence of contact with the source of infection of underground water (OR=3.26, 95 per centIC 1.22 to 8.72), and the contact with dogs in the water source of infection (OR = 5.63, 95 per cent IC = 1.40 to 22.63) were identified as significant factors associated with leptospirosis. Conclusions. It wasconfirmed an outbreak of leptospirosis in a new epidemiological context related to a common source of underground water and associated by contact with dogs in the same source. This data will allow to expand the knowledge about this disease as well as to consider leptospirosis as an important cause of acute febrile disease.


Asunto(s)
Humanos , Brotes de Enfermedades , Factores de Riesgo , Leptospira interrogans serovar canicola , Leptospirosis , Estudios Transversales , Estudios Observacionales como Asunto , Perú
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