Aerobic Denitrification Promoting by Actinomycetes Coculture: Investigating Performance, Carbon Source Metabolic Characteristic, and Raw Water Restoration.

The coculture theory that promotes denitrification relies on effectively utilizing the resources of low-efficiency denitrification microbes. Here, the strains Streptomyces sp. PYX97 and Streptomyces sp. TSJ96 were isolated and showed lower denitrification capacity when cultured individually. However, the coculture of strains PYX97 and TSJ96 enhanced nitrogen removal (removed 96.40% of total nitrogen) and organic carbon reduction (removed 92.13% of dissolved organic carbon) under aerobic conditions. Nitrogen balance analysis indicated that coculturing enhanced the efficiency of nitrate converted into gaseous nitrogen reaching 70.42%. Meanwhile, the coculturing promoted the cell metabolism capacity and carbon source metabolic activity. The coculture strains PYX97 and TSJ96 thrived in conditions of C/N = 10, alkalescence, and 150 rpm shaking speed. The coculturing reduced total nitrogen and CODMn in the raw water treatment by 83.32 and 84.21%, respectively. During this treatment, the cell metabolic activity and cell density increased in the coculture strains PYX97 and TSJ96 reactor. Moreover, the coculture strains could utilize aromatic protein and soluble microbial products during aerobic denitrification processes in raw water treatment. This study suggests that coculturing inefficient actinomycete strains could be a promising approach for treating polluted water bodies.

Raw Water and ALS: A Unifying Hypothesis for the Environmental Agents Involved in ALS.

Different studies identified the presence of several altered genes in familial and sporadic amyotrophic lateral sclerosis (ALS) forms. The experimental data, together with the epidemiological data, would seem to suggest the existence of molecular mechanisms (e.g., axonal transport) related to these genes, together with a susceptibility of the same genes to certain environmental factors that would therefore suggest an impact of the environment on the etiopathogenesis of ALS. In our review, we considered the most relevant environmental clusters around the world, collecting different hypotheses and underlining common environmental factors among the different clusters. Moreover, further epidemiological data identified a higher risk of ALS in professional athletes and, in particular, in soccer and football players. Despite this increased risk of ALS highlighted by the epidemiological evidence in aforementioned sports, the mechanisms remain unclear. At last, the use of raw water has been associated with ALS risk. The aim of the present review is to characterize a possible relationship between these clusters, to be explored in the context of the interaction between genetic and environmental factors on the etiopathogenesis of ALS.

Health risk assessment of lake water contaminated with microcystins for fruit crop irrigation and farm animal drinking.

The health risks linked to the consumption of microcystin-accumulating crops have been increasing worldwide in toxic cyanobloom-occurring regions. The bioaccumulation of microcystins (MCs) in agricultural produce at environmentally realistic concentrations is poorly investigated. In this field study, we assessed the health risks of MCs in raw water used for irrigating fruit crops (bioaccumulation) and watering farm animals in the Lalla Takerkoust agricultural region (Marrakesh, Morocco). Thus, MCs were extracted from water and fruit samples and quantified by enzyme-linked immunosorbent assay in order to calculate the health risk indicators. MCs posed a high health-risk level to poultry and horses, with estimated daily intakes (EDI) being 14- and 19-fold higher than the recommended limits (3.1 and 2.3 µg MC-LR L-1), respectively. Furthermore, pomegranate posed the same level of risk, with EDI being 22- and 53-fold higher than the limit dose (0.04 µg MC-LR kg-1) for adults and children, respectively. There was an urgent need for guidelines regarding water use and management in MC-polluted areas, besides the setup of nature-based tools for toxin removal from raw water used in farming practices. Moreover, MCs could contaminate the human food chain, which implies further investigations of their potential accumulation in livestock- and poultry-based food.

[Distribution Characteristics and Health Risk Assessment of Emerging Contaminants from Raw Water to Drinking Water in Shanghai].

By monitoring the distribution of emerging contaminants in drinking water from the source to the tap, the concentration of algal toxins, endocrine disruptors, and antibiotics in each water supply link were determined, and the health risks of emerging contaminants to the human body were evaluated. The results showed that algal toxins in the waterworks inflow were mainly MC-RR and MC-LR, whereas the only endocrine disruptors in the waterworks inflow were bisphenol-s and estrone. The algal toxins, endocrine disruptors, and antibiotics were removed effectively after the water treatment process in the waterworks. During the monitoring period, florfenicol (FF) was mainly detected, except in January 2020 when a large number of sulfa antibiotics were detected. The removal effect of FF was obviously correlated with the form of chlorine. Compared with that of combined chlorine disinfection, free chlorine disinfection had a better effect on the removal of FF. The health risk numbers of algal toxins, endocrine disruptors, and antibiotics were far less than 1, especially in the secondary water supply. The results showed that the three emerging contaminants in drinking water did not pose a direct threat to human health.

Aerobic denitrification of oligotrophic source water driven by reduced metal manganese.

The lack of organic electron donors limits the potential utility of aerobic denitrification in treatment of oligotrophic source water. Here, reduced manganese (Mn) was used as an inorganic electron donor to improve the denitrification of oligotrophic source water under the high dissolved oxygen condition (7-9 mg L-1). Over 30 days, the total nitrogen removed by the treatment with reduced Mn was 76.21 ± 2.11% (maximum), substantially higher than that of the control treatment, which was 41.48 ± 2.33%. Furthermore, the addition of Mn resulted in the directional evolution of the microbial community. Water samples with Mn added showed a higher abundance of Limnohabitans, the dominant denitrifying genus, reaching 51.02%, 36.79%, and 20.19% (with 30, 50, and 70 g Mn, respectively), versus only 5.54% in the control. In biofilm, Mn promoted Hydrogenophaga and Brevundimonas growth while Pseudarthrobacter growth was promoted by 30 and 50 g Mn, but inhibited by 70 g Mn. This study demonstrates an improved performance in aerobic denitrification of water sources through the use of inorganic electron donors.

Aerobic denitrifying using actinobacterial consortium: Novel denitrifying microbe and its application.

The aerobic denitrifying capacity of actinomycete strain has been investigated recently, while little is known about nitrogen and carbon substrate removal by mix-cultured aerobic denitrifying actinobacteria (Mix-CADA) community. Hence, three Mix-CADA consortiums, named Y23, X21, and Y27, were isolated from urban lakes to investigate their aerobic denitrification capacity, and their removal efficiency for nitrate and dissolved organic carbon were >97 % and 90 %, respectively. Illumina Miseq sequencing revealed that Streptomyces was the most dominant genus in the Mix-CADA consortium. Network analysis indicated that Streptomyces exfoliates, as the core species in the Mix-CADA consortium, majorly contributed to dissolved organic carbon and total nitrogen reduction. Moreover, the three Mix-CADA consortiums could remove 78 % of the total nitrogen and 61 % of the permanganate index from the micro-polluted l water. Meanwhile, humic-like was significantly utilized by three Mix-CADA consortiums, whereas Mix-CADA Y27 could also utilize aromatic protein and soluble microbial by-product-like in the micro-polluted raw water purification. In summary, this study will offer a novel perspective for the purification of micro-polluted raw water using the Mix-CADA consortium.

Micro-polluted water resources treatment by PVDF-TiO2 membrane combined with Fe2+/sodium dithionite (DTN)/O2 pre-oxidation process.

Modifying PVDF membrane by blending hydrophilic nano TiO2 has been highly concerning, but its practical application is not well investigated. In this study, PVDF-TiO2 membrane was employed in two modes to treat micro-polluted raw water for the first time, direct membrane filtration and pre-oxidation assists membrane filtration. At two filtration modes, the PVDF-TiO2 membrane had comparable rejection capability to the unmodified PVDF membrane, as the removal of permanganate index (CODMn) was 0.26-0.72 mg/L, UV254 was 0.0070-0.0618 cm-1, turbidity was 1.60-4.49 NTU, and the total number of colonies was 360-23,780 CFU/mL. As for raw water treatment, using Fe2+/sodium dithionite (DTN)/O2 system as the pre-oxidation process to assist the filtration of the PVDF-TiO2 membrane was feasible. After optimization, the applicable conditions of the Fe2+/DTN/O2 process were DTN dosage at 100 mg/L and a CFe/CDTN of 1:4. As a result, the effluent qualities of the PVDF-TiO2 membrane significantly improved. It was investigated that atrazine (ATZ), CODMn, UV254, and turbidity reduced, which was realized by the synergic effects of the pre-oxidation by free radicals and flocculation by iron. Pre-oxidation of the Fe2+/DTN/O2 process could also enhance the permeability of the PVDF-TiO2 membrane from 53.6 to 58.0 L/(m2·h), nearly two times the PVDF membrane. Besides, the practical fouling of the PVDF-TiO2 membrane was stably alleviated by the reduced Rt, Rre, and Rir, mainly due to constraining the internal pore fouling effectively.

Chromophoric dissolved organic compounds in urban watershed and conventional water treatment process: evidence from fluorescence spectroscopy and PARAFAC.

This study aimed to investigate the origin, quantity, and composition of chromophoric dissolved organic matter (CDOM) from two urbanized watersheds (Cikapundung and Cimahi River), examine how CDOM compounds and absorbances change along the process of two different conventional WTPs (WTP Dago and Cimahi) using PARAFAC, and identify absorbance as potential surrogate parameters for CDOM compounds. Samples were collected from intake, secondary treatment, and filter outlets. PARAFAC was conducted based on two data scenarios: (1) from rainy and dry seasons in Cikapundung river and WTP Dago and (2) from the two rivers and two WTPs during rainy season. Tryptophan-like (C1A) and humic-like (C2A) compounds were identified based on scenario-1 analysis. For scenario-2, humic-like (C1B), peak-M (C2B), and tryptophan-like (C3B) were the main compounds. CDOM compound quantity is consistent with the fluorescence index (FI) and biological index (BIX) which confirmed sewage and animal manure pollution in both watersheds. The best overall removal of CDOM compound occurred in WTP Dago in rainy season. The high concentration of tryptophan-like in Cikapundung River in dry season and in Cimahi River in rainy season has worsen the WTP capability to reduce CDOM. Scenario-1 has shown that in WTP Dago, the potential surrogate parameter for C1A was A240 in rainy season (r = 0.60; p < 0.01) and A410 in dry season (r = - 0.43, p < 0.05). Based on scenario-2, for the WTP Dago in rainy season, C1B strongly correlated with A254 (r = 0.86; p < 0.01), C2B has the strongest correlation with A298 (r = 0.93; p < 0.01), and C3B correlated well with A240 (r = 0.59; p < 0.01). In WTP Cimahi, during rainy season, all compounds correlated well with all measured absorbances, with the strongest correlation with A298.

[Determination of 107 typical pesticides and metabolites in raw water and drinking water by online-solid phase extraction coupled with ultra performance liquid chromatography-triple quadrupole mass spectrometry].

In order to monitor the risk of pesticide pollutants in drinking water, an analytical method based on online-solid phase extraction coupled with ultra performance liquid chromatography-triple quadrupole mass spectrometry (online-SPE-UPLC-MS/MS) was established for the simultaneous rapid screening and determination of 107 pesticides and metabolites (organophosphorus, organic nitrogen, organic heterocycle, carbamate, amide, benzoyl urea, neonicotinoid, etc.) in raw water and drinking water. Different injection volumes (5, 10, and 15 mL) were compared. The detection response increased with an increase in the injection volume, but the matrix effect also became more pronounced. Under the premise of ensuring the sensitivity of the method and meeting the detection requirements, the injection volume was selected as 5 mL. Accordingly, the samples were filtered through a 0.22-µm hydrophilic polytetrafluoroethylene filter, and then, 5 mL samples were injected into the online-SPE system by the automatic sampler. After adsorption on an X Bridge C18 online-SPE column, the samples were washed with pure water and eluted by gradient elution using acetonitrile and 0.1% formic acid aqueous solution as the mobile phases, with separation on an ACQUITY HSS T3 column. The samples were detected by multiple reaction monitoring with electrospray ionization in positive and negative ion modes, and quantified by an external standard method. Using raw water and drinking water as the sample matrices, the accuracy and precision of the method were verified. The 107 pesticides and metabolites showed good linear relationships in different ranges with correlation coefficients (r2)>0.995. The limits of detection (LODs, S/N=3) of the method were 0.03-1.5 ng/L, and the limits of quantification (LOQs, S/N=10) were 0.1-5.0 ng/L. The target pesticides were spiked at concentration levels of 1, 20, and 50 ng/L. The spiked recoveries of the 107 targets in raw water and drinking water samples were 60.6%-119.8% and 61.2%-119.0%, respectively. The corresponding relative standard deviations (RSDs, n=6) were 0.3%-18.6% and 0.4%-17.1%. The pesticide residues in raw water and drinking water were determined by this method. Amide herbicides, triazine herbicides, triazole insecticides, carbamate insecticides, and neonicotinoid insecticides had high detection rates. The detected concentrations ranged from 0.1 to 97.1 ng/L in raw water and from 0.1 to 93.6 ng/L in drinking water. The sample consumption of online-SPE method was lower than that in the traditional off-line SPE methods, which greatly improved the convenience of sample collection, storage, and transportation. The samples only need to be filtered before injection and analysis. The method is simple to operate and shows good reproducibility. With this online-SPE method, only 23 min were required from online enrichment to detection completion. The developed method has the advantages of high analytical speed and high sensitivity. The method is suitable for the trace analysis and determination of 107 typical pesticides in raw water and drinking water, which effectively improves the detection efficiency of pesticides in water and has high potential for practical application. It can extend technical support for the pollution-level analysis of typical pesticides and metabolites in drinking water and provide an objective basis for human health risk assessment.

Insights into the Seasonal Olfactory Mechanism of Geosmin in Raw Water of Huangpu River.

Since the 1990s, the raw water of Huangpu River in Shanghai, China, has intermittently encountered off-flavor contamination. In this work, the concentrations of typical odor, geosmin, in raw water of Huangpu River are found to shift along with the seasons. However, microbes recognized as the producer of geosmin such as Cyanobacteria and Actinobacteria are not consistent with the shift of geosmin. Cyanobacteria blooms in summer rather than winter, whereas Actinobacteria thrives in winter. Representational difference analysis (RDA) reveals that microbes associated with blooming algae have positive co-occurrence correlations with the concentrations of geosmin and nutrients in winter, whereas those within Cyanobacteria and Planctomycete are in a positive correlation with temperature and thrive in summer. This causes the concentration of geosmin in raw water to appear to depend on the abundance of Actinobacteria rather than that of Cyanobacteria. However, combining with the synthesis and storage properties of geosmin in algae, as well as the decomposition properties of algae with Actinobacteria, geosmin might be synthesized by Cyanobacteria in summer, which is stored in cells of Cyanobacteria and released only via the decomposition of Actinobacteria in winter. This potential olfactory mechanism of geosmin is quite different from that derived from pure culture of odor producers or correlation analysis of bacteria and odors; thus, providing insights into the mechanism of practical off-flavor events.

Chemical, radiological and microbiological characterization of a drinking water source: a case study.

This study examined water samples from a local stream in Central Serbia, which was consumed as drinking water. The chemical parameters (chemical oxygen demand, COD; pH, total concentration of dissolved substances and electrical conductivity), the concentration of major, trace and radioactive elements in the water as well as the content of those from the environment, were examined. In addition, the microbiological quality of the water was inspected. The water samples were acidic (pH from 5·27-5·69) and COD ranged in upper permissible limits (up to 6·25 mg O2 l-1 [WR]). The concentrations of major, trace and radioactive elements, including radon, were below maximum contaminant levels. The water contained a higher number of total coliform bacteria (TCB) than it was allowed (˃10 colony-forming units (CFU) in 100 ml of water) as well as enterococci and Escherichia coli. The characterization of the isolated bacteria indicated that two isolates demonstrated proteolytic activity, while full antibiotic resistance was not detected. The isolates showed moderate to strong ability to produce biofilm, while the isolates of E. coli were nonpathogenic. The results indicated that examined water samples were not microbiologically and chemically safe, therefore, the usage of analysed water was not recommended as a water supply. Further research needs to include more frequent monitoring in order to propose measures for the improvement of the water quality and prevention of health risks for consumers.

Algae-containing raw water treatment and by-products control based on ClO2 preoxidation-assisted coagulation/precipitation process.

Eutrophication has become a great concern in recent years with the algae blooms in source water resulting in a serious threat posing to the safety of drinking water. Chlorine dioxide (ClO2) has been served as an alternative oxidant for preoxidation or disinfection during drinking water treatment process due to its high oxidation efficiency and low risk of organic by-products formation. However, the generation of inorganic by-products including chlorite (ClO2-) and chlorate (ClO3-) has become a potential problem when applied in drinking water treatment. In this study, ClO2 preoxidation-assisted coagulation/precipitation process was applied to improve the raw water quality, especially algae, turbidity, chemical oxygen demand (CODMn), and UV254, and explore the formation mechanisms of inorganic by-products. It was found that the polymeric aluminum chloride (PAC) and ClO2 have shown the best raw water treatment performance with the optimal dosage of 10 mg/L and 0.8 mg/L, respectively. Moreover, the initial pH also has exhibited a notable influence on pollutants treatment and by-products generation. Due to the adverse influence of algae and natural organic matters (NOM) and the generation of by-products, it was significant to investigate their inhibition effect on the water quality and the production of ClO2- and ClO3- in the ClO2 preoxidation-assisted coagulation/precipitation process. Moreover, it was applicable of this process to apply for the algae-containing raw water (calculated as Chl.a lower than 50 µg/L) treatment with the ClO2 dosage of less than 0.8 mg/L to achieve optimum treatment performance and minimum by-products generation.

Identification of enteric viruses from raw water using fluoro-immuno-magnetic separation coupled to RT-PCR. / Identificación de virus entéricos en aguas crudas usando separación inmunomagnética acoplada a RT-PCR

INTRODUCTION: Enteric viruses have been associated with the production of a variety of diseases transmitted by the fecal-oral route and carried through contaminated food and water. Given their structure and composition, they are highly resistant to environmental conditions and most of the chemical agents used in the purification processes. Therefore, the systematic monitoring of raw water is necessary to ensure its quality especially when it is used for producing drinking water for human consumption. OBJECTIVE: We identified the presence of rotavirus and hepatitis A virus by means of the fluoro-immuno-magnetic separation technique (FIMS) in raw water taken from four purification plants and their water supplies in the department of Norte de Santander. MATERIALS AND METHODS: The viruses were captured and separated from the water samples using magnetic microparticles functionalized with monoclonal anti-Hepatitis A and anti-Rotavirus antibodies. Confocal microscopy was used to monitor the viral concentration process and transmission electron microscopy for the morphological visualization of the separated viruses. The reverse transcriptase-coupled polymerase chain reaction (RT-PCR) was applied to confirm the presence of pathogens. RESULTS: The two enteric viruses were identified in the majority of the analyzed water samples including water supply sources. CONCLUSION: We determined that the FIMS technique together with RT-PCR is highly effective for the detection of viral pathogens in complex matrices such as raw water.

Introducción. Los virus entéricos se asocian con una serie de enfermedades transmitidas por vía fecal-oral en alimentos o agua contaminada. Dada su estructura y composición, son muy resistentes a las condiciones ambientales y a la mayoría de los agentes químicos empleados en los procesos de potabilización, por lo cual es necesario un monitoreo sistemático del agua cruda para asegurar su calidad, máxime cuando se emplea como materia prima en la producción de agua potable para consumo humano. Objetivo. Determinar la presencia de rotavirus y del virus de la hepatitis A mediante la técnica de separación fluoro-inmuno-magnética en agua cruda procedente de cuatro plantas de potabilización y sus fuentes hídricas en el departamento de Norte de Santander. Materiales y métodos. Los virus fueron capturados y separados a partir de las muestras de agua, empleando micropartículas magnéticas funcionalizadas con anticuerpos monoclonales anti-hepatitis A y anti-rotavirus. Se empleó microscopía confocal para hacer el seguimiento del proceso de concentración viral y, microscopía electrónica de transmisión, para la visualización morfológica de los virus separados. La reacción en cadena de la polimerasa acoplada a transcriptasa inversa (RT-PCR) se utilizó para confirmar la presencia de los patógenos. Resultados. Los dos virus entéricos se detectaron en la mayoría de las muestras de agua analizadas, incluidas las de sus fuentes hídricas. Conclusión. La técnica de separación fluoro-inmuno-magnética acoplada a RT-PCR fue altamente efectiva en la detección de patógenos virales en matrices complejas como el agua cruda.

Applicability of a Combined DAF-MF Process to Respond to Changes in Reservoir Water Quality through a Two-Year Pilot Plant Operation.

The optimal operating conditions of a combined dissolved air flotation (DAF)-microfiltration (MF) process to respond to changes in raw water quality were investigated by operating a pilot plant for two years. Without DAF pre-treatment (i.e., MF alone), MF operated stably with a transmembrane pressure (TMP) increase of 0.24 kPa/d when the turbidity of raw water was low and stable (max. 13.4 NTU). However, as the raw water quality deteriorated (max. 76.9 NTU), the rate of TMP increase reached 43.5 kPa/d. When DAF pre-treatment was applied (i.e., the combined DAF-MF process), the MF process operated somewhat stably; however, the rate of TMP increase was relatively high (i.e., 0.64 kPa/d). Residual coagulants and small flocs were not efficiently separated by the DAF process, exacerbating membrane fouling. Based on the particle count analysis of the DAF effluent, the DAF process was optimised based on the coagulant dose and hydraulic loading rate. After optimisation, the rate of TMP increase for the MF process stabilised at 0.17 kPa/d. This study demonstrates that the combined DAF-MF process responded well to substantial changes in raw water quality. In addition, it was suggested that the DAF process must be optimised to avoid excessive membrane fouling.

Identification of enteric viruses from raw water using fluoro-immuno-magnetic separation coupled to RT-PCR / Identificación de virus entéricos en aguas crudas usando separación inmuno-magnética acoplada a RT-PCR

Abstract | Introduction: Enteric viruses have been associated with the production of a variety of diseases transmitted by the fecal-oral route and carried through contaminated food and water. Given their structure and composition, they are highly resistant to environmental conditions and most of the chemical agents used in the purification processes. Therefore, the systematic monitoring of raw water is necessary to ensure its quality especially when it is used for producing drinking water for human consumption. Objective: We identified the presence of rotavirus and hepatitis A virus by means of the fluoro-immuno-magnetic separation technique (FIMS) in raw water taken from four purification plants and their water supplies in the department of Norte de Santander. Materials and methods: The viruses were captured and separated from the water samples using magnetic microparticles functionalized with monoclonal anti-Hepatitis A and anti-Rotavirus antibodies. Confocal microscopy was used to monitor the viral concentration process and transmission electron microscopy for the morphological visualization of the separated viruses. The reverse transcriptase-coupled polymerase chain reaction (RT-PCR) was applied to confirm the presence of pathogens. Results: The two enteric viruses were identified in the majority of the analyzed water samples including water supply sources. Conclusion: We determined that the FIMS technique together with RT-PCR is highly effective for the detection of viral pathogens in complex matrices such as raw water.

Resumen | Introducción. Los virus entéricos se asocian con una serie de enfermedades transmitidas por vía fecal-oral en alimentos o agua contaminada. Dada su estructura y composición, son muy resistentes a las condiciones ambientales y a la mayoría de los agentes químicos empleados en los procesos de potabilización, por lo cual es necesario un monitoreo sistemático del agua cruda para asegurar su calidad, máxime cuando se emplea como materia prima en la producción de agua potable para consumo humano. Objetivo. Determinar la presencia de rotavirus y del virus de la hepatitis A mediante la técnica de separación fluoro-inmuno-magnética en agua cruda procedente de cuatro plantas de potabilización y sus fuentes hídricas en el departamento de Norte de Santander. Materiales y métodos. Los virus fueron capturados y separados a partir de las muestras de agua, empleando micropartículas magnéticas funcionalizadas con anticuerpos monoclonales anti-hepatitis A y anti-rotavirus. Se empleó microscopía confocal para hacer el seguimiento del proceso de concentración viral y, microscopía electrónica de transmisión, para la visualización morfológica de los virus separados. La reacción en cadena de la polimerasa acoplada a transcriptasa inversa (RT-PCR) se utilizó para confirmar la presencia de los patógenos. Resultados. Los dos virus entéricos se detectaron en la mayoría de las muestras de agua analizadas, incluidas las de sus fuentes hídricas. Conclusión. La técnica de separación fluoro-inmuno-magnética acoplada a RT-PCR fue altamente efectiva en la detección de patógenos virales en matrices complejas como el agua cruda.

Detection of Toxoplasma gondii in water for human consumption from water wells (jagüeyes) in the rural area of the municipality of Sincelejo / [Detección de Toxoplasma gondii en agua para el consumo humano proveniente de jagüeyes del área rural del municipio de Sincelejo].

Introduction: Toxoplasmosis is an orally-transmitted zoonosis that may appear after consuming food contaminated with any infective form of Toxoplasma gondii. Its transmission by water has been reported in several countries including Colombia. The rural population of Sincelejo could be at risk of contracting toxoplasmosis through this route given that they lack potable water. Objective: To evaluate T. gondii contamination in water for human consumption from water wells (jagüeyes) in the rural area of Sincelejo and establish its relationship with different social determinants of health in the study area. Materials and methods: Using nested PCR we evaluated 96 water samples obtained from 48 farms located in eight rural townships in Sincelejo. We took two samples in each farm: one of raw water from water wells and the other intended for direct consumption. We conducted a survey on each farm to collect information on the physical characteristics of dwellings, the presence of cats, and the availability and uses of water. Statistical relationships were evaluated through Fisher tests. Results: Of the 96 samples analyzed, 13 were contaminated with T. gondii (13.5%): Nine corresponded to raw water and four to water for direct consumption. No statistical association was found between the positive samples and the social determinants of health under evaluation (p>0.05). Conclusion: The rural population of Sincelejo could be at risk of contracting toxoplasmosis through the use and/or consumption of water from its water wells. The contamination of these water bodies by T. gondii may be influenced by unstudied social determinants.

Introducción. La toxoplasmosis es una zoonosis que se transmite por vía oral al consumir alimentos contaminados con cualquier forma infectiva de Toxoplasma gondii. Su transmisión por agua ha sido documentada en varios países, incluido Colombia. Al no disponer de agua potable, la población rural de Sincelejo podría estar en riesgo de contraer toxoplasmosis por esta vía. Objetivo. Evaluar la contaminación por T. gondii del agua para consumo humano proveniente de jagüeyes de la zona rural de Sincelejo y establecer su relación con diferentes determinantes sociales de la salud en el área de estudio. Materiales y métodos. Mediante PCR anidada, se evaluaron 96 muestras de agua obtenidas en 48 fincas ubicadas en ocho corregimientos rurales de Sincelejo. En cada finca se obtuvieron dos muestras: una de agua cruda de jagüey y otra destinada al consumo directo. En cada finca se hizo una encuesta para recolectar información sobre características físicas de la vivienda, presencia de gatos, y disponibilidad de agua y sus usos. Las relaciones estadísticas se evaluaron con el test de Fisher. Resultados. De las 96 muestras analizadas, 13 resultaron contaminadas con T. gondii (13,5 %): nueve de agua cruda y cuatro de agua para el consumo directo. No se encontró asociación estadística entre las muestras positivas y los determinantes sociales de la salud evaluados (p>0,05). Conclusión. La población rural de Sincelejo podría estar en riesgo de contraer toxoplasmosis por el uso y consumo del agua proveniente de sus jagüeyes. La contaminación de estos cuerpos de agua por T. gondii puede estar influenciada por otros determinantes sociales de la salud no contemplados aquí.

Field study on the transportation characteristics of PFASs from water source to tap water.

Perfluoroalkyl substances (PFASs) can occur in water sources, pass through drinking water treatment plants (DWTPs), drinking water distribution systems (DWDSs), to the consumer taps. This investigation was carried out to present the transportation behaviors of 17 PFASs, involving seven DWTPs with different water sources, raw water transportation modes, treatment processes, and DWDS structures in eastern and northern China. The results showed that the long-distance raw water transportation pipelines removed a certain extent of PFASs from raw water, probably due to the accumulation of loose deposits. The long-distance, open-channel South-to-North water diversion increased PFAS contamination risk. In the DWTPs, granular activated carbon (GAC) adsorption and ultraviolet radiation removed less than 25% of PFASs, but ozonation-biological activated carbon (O3-BAC) was superior to GAC alone in removing PFASs. Loose deposits couldsignificantly influence PFAS accumulation and release within branch-structured DWDSs. In loop-structured DWDSs, finished water with different PFAS characteristics could mix along the pipeline, with the corresponding DWTP as the center, ultimately forming a relatively uniform distribution in the entire DWDS.

Diatomite-enhanced coagulation for algal removal in polluted raw water: performance optimization and pilot-scale study.

Algae blooms have seriously threatened the health of aquatic ecosystems and the safety of drinking water. In this study, diatomite-enhanced coagulation technology was developed to improve the removal of algae and other pollutants. The dosage and ratio of diatomite and aluminum salts were optimized to 40mg/L and 1:1 which achieved algal removal efficiency of 98.8±0.65%. The effect of environmental factors was studied and it shows that cell density, pH, and temperature had a significant impact on algal removal. The mechanism of diatomite-enhanced coagulation was speculated to be adsorption bridging and sweep flocculation. Pilot-scale equipment was set up to verify the performance of diatomite-enhanced coagulation in engineering applications on algae polluted raw water. Results showed a better removal efficiency of algae, NH4+-N, NO2--N, and CODMn and lower operation cost than the actual operation in the Waterwork Corporation were achieved with good application prospects and promotion value.

Detección de Toxoplasma gondii en agua para el consumo humano proveniente de jagüeyes del área rural del municipio de Sincelejo / Detection of Toxoplasma gondii in water for human consumption from water wells (jagüeyes) in the rural area of the municipality of Sincelejo

Resumen | Introducción. La toxoplasmosis es una zoonosis que se transmite por vía oral al consumir alimentos contaminados con cualquier forma infectiva de Toxoplasma gondii. Su transmisión por agua ha sido documentada en varios países, incluido Colombia. Al no disponer de agua potable, la población rural de Sincelejo podría estar en riesgo de contraer toxoplasmosis por esta vía. Objetivo. Evaluar la contaminación por T. gondii del agua para consumo humano proveniente de jagüeyes de la zona rural de Sincelejo y establecer su relación con diferentes determinantes sociales de la salud en el área de estudio. Materiales y métodos. Mediante PCR anidada, se evaluaron 96 muestras de agua obtenidas en 48 fincas ubicadas en ocho corregimientos rurales de Sincelejo. En cada finca se obtuvieron dos muestras: una de agua cruda de jagüey y otra destinada al consumo directo. En cada finca se hizo una encuesta para recolectar información sobre características físicas de la vivienda, presencia de gatos, y disponibilidad de agua y sus usos. Las relaciones estadísticas se evaluaron con el test de Fisher. Resultados. De las 96 muestras analizadas, 13 resultaron contaminadas con T. gondii(13,5 %): nueve de agua cruda y cuatro de agua para el consumo directo. No se encontró asociación estadística entre las muestras positivas y los determinantes sociales de la salud evaluados (p>0,05). Conclusión. La población rural de Sincelejo podría estar en riesgo de contraer toxoplasmosis por el uso y consumo del agua proveniente de sus jagüeyes. La contaminación de estos cuerpos de agua por T. gondii puede estar influenciada por otros determinantes sociales de la salud no contemplados aquí.

Abstract | Introduction:Toxoplasmosis is an orally-transmitted zoonosis that may appear after consuming food contaminated with any infective form of Toxoplasma gondii. Its transmission by water has been reported in several countries including Colombia. The rural population of Sincelejo could be at risk of contracting toxoplasmosis through this route given that they lack potable water. Objective: To evaluate T. gondii contamination in water for human consumption from water wells (jagüeyes) in the rural area of Sincelejo and establish its relationship with different social determinants of health in the study area. Materials and methods: Using nested PCR we evaluated 96 water samples obtained from 48 farms located in eight rural townships in Sincelejo. We took two samples in each farm: one of raw water from water wells and the other intended for direct consumption. We conducted a survey on each farm to collect information on the physical characteristics of dwellings, the presence of cats, and the availability and uses of water. Statistical relationships were evaluated through Fisher tests. Results: Of the 96 samples analyzed, 13 were contaminated with T. gondii (13.5%): Nine corresponded to raw water and four to water for direct consumption. No statistical association was found between the positive samples and the social determinants of health under evaluation (p>0.05). Conclusion: The rural population of Sincelejo could be at risk of contracting toxoplasmosis through the use and/or consumption of water from its water wells. The contamination of these water bodies by T. gondii may be influenced by unstudied social determinants.

Is Chronic Exposure to Raw Water a Possible Risk Factor for Amyotrophic Lateral Sclerosis? A Pilot Case-Control Study.

BACKGROUND: The etiopathogenesis of amyotrophic lateral sclerosis (ALS) is still largely unknown. METHODS: We performed a case-control study (33 cases and 35 controls) in Umbria, Italy. We investigated associations between common lifestyle, clinical factors, as well as environmental exposures potentially implicated with ALS onset. Face-to-face interviews were carried out. All cases were recruited and diagnosed according to El Escorial criteria. Case-control comparisons were made for educational and residential status, occupational exposures, and clinical and lifestyle factors prior to cases' dates of diagnosis. RESULTS: Our results showed an increased risk of ALS for subjects chronically exposed to raw water use (odds ratio (OR) = 6.55, 95% confidence interval (CI): 2.24-19.12). Garden activities showed a tight association with ALS as well, very likely as a consequence of chronic raw water exposure. Indeed, we could exclude an impact for pesticides, as no significant differences were observed in pesticide exposure in the two groups interviewed. However, cases were more often exposed to fertilizers. After adjustment for age, sex, and heavy physical activities, exposure to raw water was still associated with increased ALS risk (OR = 4.74, 95% CI: 1.33-16.85). DISCUSSION: These findings suggest an association between ALS and exposure to raw water, which should be further investigated for the presence of chemicals interfering with nervous system functionality.