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1.
Chemosphere ; 262: 127808, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32755693

RESUMO

In terms of investigating the authentic plant biomonitoring and phytoextraction potentials, the samples of soils and shoots of the sun spurge (SS) and common nettle (CN), were collected near several polluted water bodies in the close vicinity of the copper mining/metallurgical complex in Bor (Serbia) and characterized with regard to the content of heavy metal(oid)s: As, Cd, Pb, Cu, and Zn. The methods applied in this work such as inductively coupled plasma-mass spectrometry, one-way analysis of variance, Pearson's correlation study, hierarchical cluster analysis, and the calculation of bioaccumulation rates (expressed through the so called mobility ratios, MRs), provided very informative data on the potentials of both investigated pioneer species. The most important findings were: 1) In most cases, SS was more effective in metal extraction/translocation/bioaccumulation than CN, and especially with regard to Cu; in this particular case, extremely high concentrations were recorded and also, some significant MRs were calculated, which may be a signal of its promising potential for Cu-phytoremediation, practically, Cu-phytoextraction; however, generally, the values of most calculated MRs were very low (<1, for both plants); 2) The shoots of both plants reflected soundly the current status of metal presence in the studied environment and they can be recommended for seasonal screenings of a general level of metal pollution in the areas of interest; however, specifically, they cannot reflect quite correctly the level of soil pollution; 3) Soil Cu, and As were detected in alarming concentrations.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/análise , Poluentes do Solo/análise , Biodegradação Ambiental , Monitoramento Biológico , Cobre/análise , Metalurgia , Mineração , Plantas , Sérvia , Solo/química , Poluição da Água/análise
2.
Chemosphere ; 262: 127801, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32791366

RESUMO

In this study, cost-effective cellulosic biomass based activated wood charcoal was developed from Japanese Sugi tree (Cryptomeria japonica) by concentrated nitric acid modification for adsorption of Cs from contaminated water. The physicochemical properties of specimens were investigated using N2 adsorption-desorption isotherms (BET method), FESEM, FTIR, and XPS spectra analysis. The experimental results revealed that the surface area of the raw wood charcoal was significantly decreased after boiling nitric acid modification. However, several oxygen-containing acidic function groups (-COOH, -CO) were introduced on the surface. The adsorption study confirmed that the equilibrium contact time was 1 h, the optimum adsorption pH was neutral to alkaline and the suitable adsorbent dose was 1:100 (solid: liquid). The maximum Cs was removed when the concentration of Na and K were lower (5.0 mM) with Cs in solution. The Cs adsorption processes well approved by the Langmuir isotherm and pseudo-second-order kinetic models and the maximum adsorption capacity was 35.46 mgg-1. The Cs adsorption mechanism was clearly described and it was assumed that the adsorption was strongly followed by chemisorptions mechanism based on the adsorbent surface properties, kinetic model and Langmuir isotherm model. Most importantly, about 98% of volume reduction was obtained by burning (500 °C) the Cs adsorbed charcoal, which ensured safe storage and disposal of radioactive waste. Therefore, this study can offer a guideline to produce a functional adsorbent for effective Cs removal and safe radioactive waste disposal.


Assuntos
Césio/química , Poluentes Químicos da Água/química , Madeira/química , Adsorção , Biomassa , Carvão Vegetal/química , Concentração de Íons de Hidrogênio , Cinética , Ácido Nítrico , Propriedades de Superfície , Poluentes Químicos da Água/análise , Poluição da Água/análise
3.
J Environ Manage ; 277: 111413, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33035938

RESUMO

Surface waters listed on impaired waters (303 d) lists due to pathogen contamination pose a significant environmental and public health burden. The need to address impairments through the Total Maximum Daily Load (TMDL) process has resulted in method developments that successfully identify nonpoint fecal pollution sources by maximizing available resources to improve water quality. However, the ability of those methods to effectively and universally identify sources of fecal pollution requires further evaluation. The objective of this research was to assess the usefulness of a previously described multivariate statistical approach to identify common patterns influencing fate and transport of fecal pollutants from sources to receiving streams using the Tuckasegee River watershed in Western North Carolina as a test watershed. Two streams were routinely monitored using a targeted sampling approach to assess fecal pollution extent and identify nonpoint sources using canonical correlation and canonical discriminant analyses. Fecal pollution in the watershed varied spatially and temporally with significantly higher fecal coliform concentrations observed in Scott Creek (f = 9.49, p = 0.002) and during the summer months (f = 14.8, p < 0.0001). Canonical correlations described 62-67% of water quality variability and indicate that fecal pollution in portions of the watershed are influenced by stormwater runoff and fecal indicator bacteria resuspension from sediment, while fecal pollution in other portions are influenced by soil erosion and surface runoff. Canonical discriminant analyses indicate that LULC significantly influences the nature and extent of fecal pollution. These results demonstrate that chemical parameters are useful predictors of fecal pollution and can help identify nonpoint fecal pollution sources in relation to land use patterns and land management practices. This approach to water quality monitoring program design and data analysis may effectively and efficiently identify parameters that best predict fecal pollution to aid in development and implementation of effective TMDLs to remediate impaired waters.


Assuntos
Monitoramento Ambiental , Rios , Fezes , Análise Multivariada , North Carolina , Microbiologia da Água , Poluição da Água/análise , Qualidade da Água
4.
J Environ Manage ; 277: 111342, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33080433

RESUMO

Water quality is continuously changing because of anthropogenic origin of point and diffuses (non-point) pollution sources. Most of the time diffuse sources are not considered for rationalization of sampling sites as their accurate estimation is tedious and data intensive. The estimation of diffuse pollution is conventionally carried out using observed water quality data. These conventional approaches are data intensive and demands detailed information for a considerably long-time horizon and hence becomes challenging to implement in data-scarce regions. Also, diffuse pollution sources are characterized by spatio-temporal heterogeneity as they depend upon seasonal behavior of precipitation. The present study proposes an innovative semi-empirical approach of Seasonal Export Coefficients (SECs) for estimation of diffuse pollution loads, especially for tropical countries like India. This approach takes into account the effect of seasonality on the estimation of diffuse pollution loads, by considering seasonal heterogeneity of terrain and precipitation impact factors and land use applications. This seasonal heterogeneity is then tested for its possible impact on rationalization of water quality monitoring locations for Kali River basin in India. The SECs are estimated for available water quality dataset of 1999-2000 and are further used for simulation of nutrient loading for experimental years 2004-2005, 2009-2010, and 2014-2015. The resulting SECs for Kali river basin are: 2.03 (agricultural), 1.44 (fallow), and 0.92 (settlement) for monsoonal nitrate; while for non-monsoonal nitrate, SECs are 0.51 (agricultural), 0.23 (fallow), and 0.10 (settlement). The monsoonal phosphate SECs for land use classes - agricultural, fallow and settlement are 1.01, 0.68, and 0.25, while non-monsoonal phosphate SECs are 0.27, 0.14 and, 0.03 respectively. The seasonal variation of diffuse pollution sources is effectively captured by SECs. The proposed approach, by considering both point and diffuse pollution, is found efficient in determining optimum locations and number of monitoring sites where seasonal variations are found evident during experimental years.


Assuntos
Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental , Índia , Racionalização , Rios , Estações do Ano , Água , Poluentes Químicos da Água/análise , Poluição da Água/análise
5.
Environ Monit Assess ; 192(12): 745, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33141366

RESUMO

The increasingly serious water pollution of rivers has attracted wide attention from all countries in the world. Investigating spatial variations of water pollution and source apportionment is particularly important for the effective management of river quality. The water samples collected every two months at 31 sampling sites containing 12 water quality parameters during 2018 and 2019 were analyzed to investigate the spatial patterns and the apportionment of the pollutants in the Tuo River. Cluster analysis (CA), pollution index (PI), factor analysis (FA), principal component analysis (PCA), and absolute principal component score-multiple linear regression (APCS-MLR) were used in the current study. The PI found that the Tuo River was most severely polluted with phosphorus and nitrogen. Additionally, compared with that in 2018, the water quality in the Tuo River has significantly improved in 2019. The CA divided the sampling sites into three categories, which are defined as clean, low-polluted, and moderate-polluted areas, respectively. FA/PCA resulted in four latent pollution sources, explaining 74.09% of the total variance. The contributions of the identified pollution sources to pollutants were realized using APCS-MLR. Most variables were mainly affected by the pollution of agricultural runoff, industrial wastewater, domestic sewage, and soil weathering. According to the results, we can also find that agricultural runoff and industrial wastewater were dominating in the Tuo River. These results provide a scientific basis for formulating more reasonable and strict pollution control strategies for the Tuo River.


Assuntos
Rios , Poluentes Químicos da Água , China , Monitoramento Ambiental , Análise de Componente Principal , Poluentes Químicos da Água/análise , Poluição da Água/análise , Qualidade da Água
6.
J Environ Qual ; 49(3): 603-612, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016399

RESUMO

There is growing recognition of the importance of involving stakeholders in solution-oriented multidisciplinary environmental research projects. Management of nutrients to address water pollution is a wicked problem requiring multidisciplinary research and participation of stakeholders. Here, we frame participatory research as shared discovery, a deliberative, focused engagement process that serves as a directional guide for how research unfolds during the entire span of a project. We explore its application within a 5-yr, multidisciplinary research project seeking innovative solutions to nutrient management challenges in four agriculturally influenced small watersheds in the Chesapeake Bay basin. This process involved deliberate development of a stakeholder engagement strategy and structure, which included a specific research team dedicated to implementing shared discovery throughout. Recognizing that stakeholders involved in nutrient and watershed management engage at multiple scales, we developed a biscalar approach to engage stakeholders at both a regional or state policy level and within the local study watersheds. Early collaboration allowed stakeholders to be participatory in developing research questions and shaping research design, which made research results more applicable to the identified problems. The biscalar framework for engagement was a novel approach that allowed researchers to incorporate both broader policy concepts into research and local concerns and concepts specific to the small study watersheds, allowing solutions to be tailored to local needs. Although infusing research with stakeholder engagement and input from the outset is a time-consuming process, it bolsters research design and products and leads to greater application of research to solve nutrient pollution-a wicked problem indeed.


Assuntos
Pessoal Administrativo , Participação dos Interessados , Humanos , Nutrientes , Poluição da Água/prevenção & controle
7.
Environ Monit Assess ; 192(11): 677, 2020 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-33025276

RESUMO

Local water quality indices (WQIs) are usually developed by modifying internationally recognized indices, which are considered reference index. In previous works on WQIs, the performance of local and reference indices has not been compared with each other. Therefore, the question crosses the mind whether using local or international indicators individually can show all qualitative aspects of a water resource. In this study, it was aimed to make this comparison between NSFWQIm (National Sanitation Foundation Water Quality Index) as the reference index and IRWQIsc (Iranian Water Quality Index for Surface Water Resource-Conventional Parameters) as the local one through a case study (Sefidroud River in northern Iran). Based on the results, the indices' performance in representing the seasonal and spatial fluctuations of the river water quality was almost similar. However, the water quality scores obtained by the two indices were somewhat different. Based on NSFWQIm, the average water quality score of the river was about 49.0, by which the water was categorized in "bad" class, while IRWQIsc represented an average score of 56.1, which corresponds to "fairly good" class. Therefore, NSFWQIm identified the water quality with stricter criteria than IRWQIsc, regarding the public health. On the other hand, according to relative standard deviations (0.17 for NSFWQIm, 0.21 for IRWQIsc) of the obtained water qualities, IRWQIsc better distinguished between high and low water qualities of the river. Accordingly, in order to better interpret the quality conditions of surface water resources in Iran, it is necessary to use both indices since NSFWQIm (reference index) attracts attention to stricter international standards and requirements, while IRWQIsc (local index) causes more focus on seasons or locations with the worst water quality.


Assuntos
Rios , Qualidade da Água , Monitoramento Ambiental , Irã (Geográfico) , Poluição da Água/análise
8.
Artigo em Inglês | MEDLINE | ID: mdl-32872245

RESUMO

Air and water pollution have detrimental effects on health, while physical activity opportunities have a positive relationship. The purpose of this study was to explore whether physical activity opportunities moderate the relationships among air and water pollution, and measures of health. Aggregate data were collected at the county level in the United States (n = 3104). Variables included the mean daily density of fine particle matter (air pollution), reported cases of health-related drinking water violations (water pollution), subjective ratings of poor or fair health (overall health), the number of physically and mentally unhealthy (physical and mental health, respectively), and the percentage of people living in close proximity to a park or recreation facility (access to physical activity). Air and water pollution have a significant positive effect on all measures of residents' poor health, while physical activity opportunities only have a negative effect on overall health and physical health. Access to physical activity only moderates the relationship between air pollution and all health outcomes. Since physical activity behavior can be more rapidly changed than some causes of pollution, providing the resident population with better access to physical activity can represent an effective tool in environmental health policy.


Assuntos
Poluentes Atmosféricos/efeitos adversos , Poluição do Ar/efeitos adversos , Exercício Físico/fisiologia , Material Particulado/efeitos adversos , Poluição da Água , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Água Potável , Poluição Ambiental , Nível de Saúde , Humanos , Saúde Mental , Material Particulado/análise , Estados Unidos
9.
Mar Pollut Bull ; 160: 111546, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32898736

RESUMO

Urban beaches are frequently impacted from multiple sources of fecal contamination. This along with high beach usage underscores the importance of appropriate management that protects swimmer health. The USEPA has enabled the use of QMRA as a tool for quantifying swimmer health risk and setting site-specific water quality objectives. This study illustrates the challenges associated with human and non-human source identification and how these challenges influence the decision of whether QMRA at typical urban beaches for water quality management is appropriate. In this study, a similar and correlated spatial relationship with elevated Enterococcus and avian-specific markers was observed, suggesting shorebirds as a primary source of FIB. However, human-associated markers were also detected frequently but at low concentrations. Ultimately, a QMRA was not conducted because pathogen loading from potential human sources could not be confidently quantified, having consequences for health risk in receiving waters where recreational contact occurs.


Assuntos
Microbiologia da Água , Poluição da Água , Praias , Monitoramento Ambiental , Fezes , Humanos , Medição de Risco , Poluição da Água/análise , Qualidade da Água
10.
Bioresour Technol ; 318: 124044, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32889120

RESUMO

Three plant biomasses (miscanthus, ryegrass and wheat) have been considered for the preparation of five different sorbents evaluated for their potential to sorb cadmium and lead and four emergent organic compounds (diclofenac, sulfamethoxazole, 17α-ethynylestradiol and triclosan) from artificially contaminated water. Lab-created cartridges were filled with each sorbent and all experiments were systematically compared to activated charcoal Norit®. Results from activated charcoal, wheat straw and acidified wheat straw were supported by the Langmuir and Freundlich models. Wheat straw ashes were an excellent metal extractor that exceeded the potential of well-known activated charcoal. Acidified sorbents (wheat and ryegrass) were very effective in eliminating the selected emerging organic contaminants displaying equipotent or superior activity compared to activated charcoal. These results open the way for further in natura studies by proposing new biosource materials as new effective tools in the fight against water pollution.


Assuntos
Poluentes Ambientais , Lolium , Poluentes do Solo , Adsorção , Biomassa , Carvão Vegetal , Solo , Poluentes do Solo/análise , Triticum , Poluição da Água
11.
Sci Total Environ ; 741: 140071, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32887015

RESUMO

The application of quantitative polymerase chain reaction (qPCR) based microbial source tracking (MST) marker genes are increasingly being used to identify contaminating sources and inform management decisions. In this study, we assessed interlaboratory agreement on duplicate environmental water samples collected from estuarine and freshwater locations, by comparing results of qPCR based testing for Bacteroides HF183, crAssphage CPQ_056, and pepper mild mottle virus (PMMoV). The overall agreements (co-detection and non-co-detection) between CSIRO Land and Water (CLW) laboratory and Sydney Water (SW) laboratory for the HF183, crAssphage CPQ_056 and PMMoV marker genes for duplicate water samples were 74, 75 and 74%, respectively. Cohene's kappa (k) revealed fair to moderate agreements and acceptable relative percent difference (RPD) values of <15% for duplicate samples. The pooled mean abundances of HF183, CPQ_056, and PMMoV in measurable samples at the CLW laboratory were 5.19 ± 0.93, 5.12 ± 0.82, and 4.42 ± 0.65 log10 copies/L, respectively. However, the pooled mean abundances were significantly lower at the SW laboratory, HF183 (4.58 ± 0.84 log10 copies/L), crAssphage CPQ_056 (4.20 ± 0.63 log10 copies/L), and PMMoV (3.89 ± 0.41 log10 copies/L). At individual sample level, most of the paired samples had <1 log10 difference. Significant positive Spearman rank correlations were obtained between two laboratories for the HF183 (Rs = 0.65; p < 0.05), CPQ_056 (Rs = 0.79; p < 0.05), and PMMoV (Rs = 0.54; p < 0.05) marker genes. Several factors such as standards, qPCR platforms, PCR inhibitors, nucleic acid extraction efficiency and low levels of targets in some samples may have contributed to the observed discrepancies. Results presented in this study highlight the importance of standardized protocol, laboratory equipment (such as digital PCR), sample processing strategies and appropriate quality controls that may need implementation to further improve accuracy and precision of results between laboratories.


Assuntos
Rios , Esgotos , Monitoramento Ambiental , Fezes , Água Doce , Microbiologia da Água , Poluição da Água/análise
12.
Water Sci Technol ; 82(2): 351-363, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32941176

RESUMO

The migration of nitrogen (N) and phosphorous (P) from farmland to river not only results in fertilizer inefficiency, but also aggravates water pollution and eutrophication. It is of great significance to construct a reasonable vegetation buffer zone between the river and farmland to protect water quality. By using constructed buffer strips and runoff hydrometric devices, quantitative research was conducted on removal loads of N and P in a field experiment of different vegetated and slope strips. Results showed that removal rates of TN, NH4+-N, and TP by different vegetated strips were 2-3 times higher than the control group. The removal ratios of seepage accounted for 73.6%, 66.9%, 73.9% of total seepage and runoff in three vegetated strips, respectively. On the 2% gradient strips with Cynodon dactylon, the removal ratios of TN, NH4+-N, and TP were 36%, 34%, 37%, which were higher than that with 5% gradient, respectively. And removal ratios from the seepage of 2%, 3%, 4%, and 5% gradient strips were 71.66%, 68.14%, 64.39%, and 61.93% of the total, respectively. The conclusion can provide the basis of vegetation and slope optimization for the design and construction of a riparian buffer zone, so as to control non-point source pollution effectively.


Assuntos
Nitrogênio/análise , Fósforo , Fertilizantes , Rios , Poluição da Água
13.
Chemosphere ; 258: 127412, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32947661

RESUMO

The objective of this study was development of a simple and reliable microbial toxicity test based on fermentative bacteria to assess heavy metal (Hg2+, Cu2+, Cr6+, Ni2+, As5+, or Pb2+)-contaminated water. The dominant species of test organisms used in this study was a spore-forming fermentative bacterium, Clostridium guangxiense. Toxicity of water was assessed based on inhibition of fermentative gas production of the test organisms, which was analyzed via a syringe method. Overall, the fermentative bacteria-based test kits satisfactorily identified increased toxicity of water as water was contaminated with high amounts of heavy metals; however, levels of inhibition were dissimilar depending on the species of metals. Inhibitory effects of Hg2+, Cu2+, Cr6+, and Ni2+ were considerably greater than those of As5+ and Pb2+. The 24 h half-maximum effective concentrations (EC50) for Hg2+, Cu2+, Cr6+, Ni2+, As5+, and Pb2+ were analyzed to be 0.10, 0.51, 1.09, 3.61, 101.33, and 243.45 mg/L, respectively, confirming that Hg2+, Cu2+, Cr6+, and Ni2+ are more toxic to fermentative gas production than As5+ and Pb2+. The fermentative bacteria-based toxicity test represents an improvement over other existing toxicity tests because of ease of end-point measurement, high reproducibility, and favorable on-site field applicability. These advantages make the fermentative bacteria-based test suitable for simple and reliable toxicity screening for heavy metal-contaminated water.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Poluentes Químicos da Água/toxicidade , Bactérias , Clostridium , Fermentação , Mercúrio/análise , Metais Pesados/análise , Reprodutibilidade dos Testes , Poluentes Químicos da Água/análise , Poluição da Água/análise
15.
Sci Total Environ ; 747: 141124, 2020 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-32795790

RESUMO

Fecal contamination is observed downstream of municipal separate storm sewer systems in coastal North Carolina. While it is well accepted that wet weather contributes to this phenomenon, less is understood about the contribution of the complex hydrology in this low-lying coastal plain. A quantitative microbial assessment was conducted in Beaufort, North Carolina to identify trends and potential sources of fecal contamination in stormwater receiving waters. Fecal indicator concentrations were significantly higher in receiving water downstream of a tidally submerged outfall compared to an outfall that was permanently submerged (p < 0.001), though tidal height was not predictive of human-specific microbial source tracking (MST) marker concentrations at the tidally submerged site. Short-term rainfall (i.e. <12 h) was predictive of E. coli, Enterococcus spp., and human-specific MST marker concentrations (Fecal Bacteroides, BacHum, and HF183) in receiving waters. The strong correlation between 12-hr antecedent rainfall and Enterococcus spp. (r = 0.57, p < 0.001, n = 92) suggests a predictive model could be developed based on rainfall to communicate risk for bathers. Additional molecular marker data indicates that the delivery of fecal sources is complex and highly variable, likely due to the influence of tidal influx (saltwater intrusion from the estuary) into the low-lying stormwater pipes. In particular, elevated MST marker concentrations (up to 2.56 × 104 gene copies HF183/mL) were observed in standing water near surcharging street storm drain. These data are being used to establish a baseline for stormwater dynamics prior to dramatic rainfall in 2018 and to characterize the interaction between complex stormwater dynamics and water quality impairment in coastal NC.


Assuntos
Estuários , Qualidade da Água , Monitoramento Ambiental , Escherichia coli , Fezes , Humanos , North Carolina , Esgotos , Microbiologia da Água , Poluição da Água/análise
16.
Water Res ; 184: 116132, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777635

RESUMO

A novel concept for fecal pollution analysis was applied at alluvial water resources to substantially extend the information provided by fecal indicator bacteria (FIB). FIB data were linked to river connectivity and genetic microbial source tracking (MST). The concept was demonstrated at the Danube River and its associated backwater area downstream of the city of Vienna, using a comprehensive 3-year data set (10 selected sites, n = 317 samples). Enumeration of Escherichia coli (ISO 16649-2), intestinal enterococci (ISO 7899-2) and Clostridium perfringens (ISO 14189) revealed a patchy distribution for the investigation area. Based on these parameters alone a clear interpretation of the observed fecal contamination patterns was not possible. Comparison of FIB concentrations to river connectivity allowed defining sites with dominating versus rare fecal pollution influence from the River Danube. A strong connectivity gradient at the selected backwater sites became obvious by 2D hydrodynamic surface water modeling, ranging from 278 days (25%) down to 5 days (<1%) of hydraulic connectivity to the River Danube within the 3-year study period. Human sewage pollution could be identified as the dominating fecal source at the highly connected sites by adding information from MST analysis. In contrast, animal fecal pollution proofed to be dominating in areas with low river connectivity. The selection of genetic MST markers was focusing on potentially important pollution sources in the backwater area, using human (BacHum, HF183II), ruminant (BacR) and pig (Pig2Bac) -associated quantitative PCR assays. The presented approach is assumed to be useful to characterize alluvial water resources for water safety management throughout the globe, by allocating fecal pollution to autochthonous, allochthonous, human or animal contamination components. The established river connectivity metric is not limited to bacterial fecal pollution, but can be applied to any type of chemical and microbiological contamination.


Assuntos
Microbiologia da Água , Recursos Hídricos , Animais , Bactérias , Monitoramento Ambiental , Fezes , Humanos , Rios , Suínos , Poluição da Água/análise
17.
Water Res ; 184: 116161, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810770

RESUMO

Current fecal indicators for environmental health monitoring are primarily based on fecal indicator bacteria (FIB) which do not accurately represent viral pathogens. There is a need for highly abundant, human-associated viral fecal indicators to represent viral pathogens in sewage-contaminated water. In the present study, we evaluate the abundance of the emerging viral fecal indicator crAssphage in 156 Italian wastewater samples collected between 2014 and 2018. Samples were collected using two separate viral concentration methods, glycine-CF and PEG-dextran and qPCR assays were run for crAssphage (CPQ56) and Human Polyomavirus (HPyV) and endpoint PCR assays were run for Human Bocavirus (HBoc) and Hepatitis E Virus (HepE). CrAssphage was detected in 96% of samples and no statistically significant difference was observed in crAssphage abundance between concentration methods (p = 0.39). CrAssphage concentrations also did not correlate with location (latitude) or size (load and capacity) of the wastewater treatment plant. HPyV detection rates with the glycine-CF and PEG-dextran methods were 64% and 100%, respectively, and the concentrations of HPyV were statistically significantly influenced by the concentration method (p < 0.0001). CrAssphage was measured at significantly higher concentrations than HPyV for both concentration methods (p < 0.0001). The observed concentration ranges were 3.84-7.29 log10GC/100 mL for crAssphage and 3.45-5.17 log10GC/100 mL for HPyV. There was a strong positive correlation between crAssphage and HPyV abundance for both concentration methods; however, the slope of the correlation depended on the concentration method. CrAssphage presence correlated with the presence of HBoc in samples concentrated with glycine-CF, but did not correlate with the presence of HBoc concentrated with the PEG-dextran method or with the presence of HepE. Overall, these results demonstrate that crAssphage is an abundant viral fecal indicator in wastewater with statistically significant correlation with human viral pathogens (e.g., HPyV) and viral concentration methods influence the interpretation of fecal viral indicator detection.


Assuntos
Águas Residuárias , Poluição da Água , Biomarcadores , Monitoramento Ambiental , Fezes , Humanos , Itália , Esgotos , Microbiologia da Água , Poluição da Água/análise
18.
Water Res ; 184: 116109, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32818744

RESUMO

This study aimed to determine the prevalence and abundance of sewage and animal fecal contamination of sediment at seven estuarine locations in Sydney, NSW, Australia. Sediment samples were tested for the occurrence of microbial targets including molecular marker genes of enterococci (ENT), Bacteroides HF183 (HF183), Methanobrevibacter smithii (nifH), human adenovirus (HAdV) and emerging sewage-associated marker genes crAssphage (CPQ_056) and Lachnospiraceae (Lachno3) and animal feces-associated marker genes, including avian feces-associated Helicobacter spp. (GFD), canine-feces associated Bacteroides (DogBact), cattle-feces associated (cowM2) and horse feces-associated Bacteroides (HoF597). Results from this study showed that urban estuarine sediment can act as a reservoir of fecal indicator bacteria (FIB) and several microbial source tracking (MST) marker genes, including previously unreported Lachno3. The sewage-associated marker gene CPQ_056 was most prevalent, in 63.8% of sediment samples, while the avian associated marker gene GFD had the highest mean abundance. The GFD marker gene was highly abundant and widely detected in sediment samples from all seven locations compared to the other animal feces-associated marker genes. In all, 31 (44.9%) sediment samples were positive for at least two sewage-associated marker genes. However, the non-quantifiable detection of the HAdV marker gene did not always align with the detection of two or more sewage-associated marker genes. In addition, the most frequent wet weather overflow exposure occurred at locations that did not have a consistent pattern of detection of the sewage-associated marker genes, suggesting sediments may not be a suitable measure of recent sewage contamination. To assist water quality and public health managers better understand past microbial contamination of estuarine sediment, further studies seem justified to explore the role of decay of MST marker genes in sediment. Further work is also needed on the role of resuspension of MST marker genes from sediment during storm events to the water column as a source of contamination for both the GFD and sewage-associated marker genes.


Assuntos
Poluição da Água , Qualidade da Água , Animais , Austrália , Bovinos , Cães , Monitoramento Ambiental , Fezes , Cavalos , Humanos , Prevalência , Esgotos , Água , Microbiologia da Água , Poluição da Água/análise
19.
Sci Total Environ ; 743: 140531, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32758812

RESUMO

The performance of eight microbial source tracking (MST) markers was evaluated in a low-resource, tropical community located in Iquitos, Peru. Fecal samples from humans, dogs, cats, rats, goats, buffalos, guinea-pigs, chickens, ducks, pigeons, and parrots were collected (n = 117). All samples were tested with human (BacHum, HF183-Taqman), dog (BactCan), pig (Pig-2-Bac), and avian (LA35, Av4143, ND5, cytB) markers using quantitative PCR (qPCR). Internal validity metrics were calculated using all animal fecal samples, as well as animal fecal samples contextually relevant for the Peruvian Amazon. Overall, Pig-2-Bac performed best, with 100% sensitivity and 88.5% specificity to detect the correct fecal source. Human-associated markers showed a sensitivity of 80.0% and 76.7%, and specificity of 66.2% and 67.6%. When limiting the analysis to contextually relevant animal fecal samples for the Peruvian Amazon, Av143 surpassed cytB with 95.7% sensitivity and 81.8% specificity. BactCan demonstrated 100% sensitivity and 47.4% specificity. The gene copy number detected by BacHum and HF183-Taqman were positively correlated (Pearson's correlation coefficient: 0.785), as well as avian markers cytB with Av4143 (Pearson's correlation coefficient: 0.508) and nd5 (Pearson's correlation coefficient: 0.949). These findings suggest that markers such as Av4143, Pig2Bac, cytb and BacHum have acceptable performance to be impactful in source attribution studies for zoonotic enteric disease transmission in this and similar low-resource communities.


Assuntos
Galinhas , Monitoramento Ambiental , Animais , Biomarcadores , Gatos , Cães , Fezes , Cobaias , Humanos , Peru , Ratos , Microbiologia da Água , Poluição da Água/análise
20.
Water Res ; 186: 116311, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32836148

RESUMO

Perfluorochemicals (PFCs) are a set of chemicals containing C-F bonds, which are concerned due to their bioaccumulation property, persistent and toxicological properties. Photocatalytic approaches have been widely studied for the effective removal of PFCs due to the mild operation conditions. This review aims to provide a comprehensive and up-to-date summary on the homogenous and heterogeneous photocatalytic processes for PFCs removal. Specifically, the homogenous photocatalytic methods for remediating PFCs are firstly discussed, including generation of hydrated electrons (eaq‒) and its performance and mechanisms for photo-reductive destruction of PFCs, the active species responsible for photo-oxidative degradation of PFCs and the corresponding mechanisms, and metal-ion-mediated (Fe(III) mainly used) processes for the remediation of PFCs. The influences of molecular structures of PFCs and water matrix, such as dissolved oxygen, humic acid, nitrate, chloride on the homogenous photocatalytic degradation of PFCs are also discussed. For heterogeneous photocatalytic processes, various semiconductor photocatalysts used for the decomposition of perfluorooctanoic acid (PFOA) are then discussed in terms of their specific properties benefiting photocatalytic performances. The preparation methods for optimizing the performance of photocatalysts are also overviewed. Moreover, the photo-oxidative and photo-reductive pathways are summarized for remediating PFOA in the presences of different semiconductor photocatalysts, including active species responsible for the degradation. We finally put forward several key perspectives for the photocatalytic removal of PFCs to promote its practical application in PFCs-containing wastewater treatment, including the treatment of PFCs degradation products such as fluoride ion, and the development of noble-metal free photocatalysts that could efficiently remove PFCs under solar light irradiation.


Assuntos
Compostos Férricos , Águas Residuárias , Substâncias Húmicas , Poluição da Água
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