Discharges of 131I coming from hospitals and outpatients in the sanitary sewage system of Bogotá.

An integral sampling methodology was applied to the sewerage network of Bogotá by inspecting wells that carry sanitary water from institutions that use 131I in nuclear medicine treatments to determine the areas of the city with activity of this radioisotope, which may reach the Salitre wastewater treatment plant and are subsequently discharged into the Bogotá river. The areas evaluated included the location of authorized institutions that use 131I in nuclear medicine and their patients. A total of 13 wells were sampled in the city, each with three samples, and the characterization of the samples was performed using the technique of high-resolution gamma spectrometry with Ge-HP detector and covered the relevant aspects that must be considered to make a complete characterization of the presence of the isotope studied. Among these factors are the season of the year with precipitation, pipe flow, location of the nuclear medicine facilities, existence of decay systems, number of rooms for treatment with 131I and water trajectory through the sewage system. Based on the results obtained, it was possible to identify potential sources of radioisotope 131I that are exceeding the discharge limits established by Colombian regulations (i.e., 19 Bq/L at the discharge point). From the 13 wells sampled, radioisotope 131I was detected in 11 of them. From the assessed wells, 3 were connected to facilities in which activity was found to be above the discharges limit allowed in Colombia for the sanitary sewer. This research complements the study on traceability of 131I in Bogotá-Colombia that begins with its importation by radiopharmacies who distribute it to hospital patients and outpatients, continuing its trajectory through management systems or homes to the sewage system of Bogotá, field that had not been studied. It allows inferring the degree of compliance with Colombian regulations and serves as a basis for evaluating regulatory changes in the levels of 131I dispensing in water networks. Further studies are required to assess the potential impacts of these materials on the local population.

Impacto da privatização da água e do esgoto nas tarifas e no acesso aos serviços no Brasil / The impact of water and sewer privatization on tariffs and access in Brazil / El impacto de la privatización del agua y del alcantarillado en las tarifas y en el acceso a los servicios en Brasil

Resumo Este trabalho se propõe a verificar o impacto das concessões à iniciativa privada dos serviços de saneamento sobre o acesso à água e ao esgoto tratados, bem como sobre as tarifas cobradas por esses serviços. O presente estudo se faz relevante à luz das recentes alterações legislativas no setor, à guisa da Lei n. 14.026/2020, e da necessidade de universalização do saneamento. Como método, foi utilizado o modelo diferenças em diferenças, para dados de 3.536 municípios brasileiros retirados do Sistema Nacional de Informações sobre Saneamento (SNIS), abrangendo o período de 1998 a 2019. Os resultados mostram impacto positivo e estatisticamente significativo dos prestadores privados (em relação aos públicos) sobre o acesso aos serviços de água, esgoto e tratamento de esgoto. Ademais, foi observado impacto positivo e estatisticamente significativo na tarifa praticada quando da concessão à iniciativa privada dos serviços, em comparação aos preços cobrados por prestadores públicos.

Abstract This paper aims to verify the impact of water and sewer services privatization on access and the tariffs charged for them. This paper is relevant mainly due to the sector's recent legal changes that resulted in Law n. 14.026/2020 and the need to universalize sanitation services in Brazil. The differences-in-differences method was employed to estimate the impact, using data from 3.536 Brazilian municipalities extracted from SNIS, the Brazilian National Sanitation Information System, for the years 1998-2019. The results show private sector operators' positive and statistically significant impact (compared to their public peers) on water and sewage services - including sewer treatment. Also, it detected a positive and statistically significant effect on the tariffs charged for those services once privatization occurs, compared to the prices charged by public sector operators.

Resumen Este trabajo se propone evaluar el impacto de las concesiones a la iniciativa privada de los servicios de saneamiento en el acceso al agua y al alcantarillado y su tratamiento, así como en las tarifas que se cobren por estos servicios. El trabajo se hace relevante a la luz de los recientes cambios legislativos en el sector, como la Ley n.o 14.026 de 2020 y de la necesidad de universalizar el saneamiento. Para el análisis se utilizó el modelo de diferencias con datos de 3536 municipios brasileños extraídos del Sistema Nacional de Información sobre Saneamiento (SNIS) que cubren el período 1998-2019. Los resultados indicaron un impacto positivo y estadísticamente significativo de los proveedores privados (en relación con los públicos) en el acceso a los servicios de agua, alcantarillado y tratamiento del alcantarillado. Además, se observó un impacto positivo y estadísticamente significativo en la tarifa cuando los servicios se concesionaron a la iniciativa privada en comparación con los precios que cobraban los proveedores públicos.

Effect of Sewerage on the Contamination of Soil with Pathogenic Leptospira in Urban Slums.

Leptospirosis is an environmentally transmitted zoonotic disease caused by pathogenic Leptospira spp. that affects poor communities worldwide. In urban slums, leptospirosis is associated with deficient sanitary infrastructure. Yet, the role of sewerage in the reduction of the environmental contamination with pathogenic Leptospira has not been explored. Here, we conducted a survey of the pathogen in soils surrounding open and closed sewer sections in six urban slums in Brazil. We found that soils surrounding conventionally closed sewers (governmental interventions) were 3 times less likely to contain pathogenic Leptospira (inverse OR 3.44, 95% CI = 1.66-8.33; p < 0.001) and contained a 6 times lower load of the pathogen (0.82 log10 units difference, p < 0.01) when compared to their open counterparts. However, no differences were observed in community-closed sewers (poor-quality closings performed by the slum dwellers). Human fecal markers (BacHum) were positively associated with pathogenic Leptospira even in closed sewers, and rat presence was not predictive of the presence of the pathogen in soils, suggesting that site-specific rodent control may not be sufficient to reduce the environmental contamination with Leptospira. Overall, our results indicate that sewerage expansion to urban slums may help reduce the environmental contamination with the pathogen and therefore reduce the risk of human leptospirosis.

Surveillance of SARS-CoV-2 in sewage and wastewater treatment plants in Mexico.

The SARS-CoV-2 virus causing COVID-19 is spread in sewage by the stool of infected individuals, and viral material in sewage can be quantified using molecular tools. This study aimed to monitor the presence of SARS-CoV-2 RNA in sewage in Mexico based on RdRP, S, and N gene analysis. The influent, effluent, and activated sludge from two domestic wastewater treatment plants (WWTP) were evaluated from the early stage of the epidemic to July 2020. Additionally, sampling points in sewer systems were examined, comparing two different RNA-concentration methods: centrifugal ultrafiltration and adsorption-based methods. The adsorption method resulted in RNA titration that was two orders of magnitude higher than with ultrafiltration (up to 3.38 log10 copies RdRP gene/mL of sewage). The surveillance of SARS-CoV-2 RNA in the influent of two WWTP correlated with the cumulative COVID-19 cases in Queretaro city. The higher RNA level in secondary sludge compared to influent suggests that viral RNA becomes concentrated in activated sludge. This result supports SARS-CoV-2 RNA removal in WWTP, where all effluent samples were negative for virus quantification. This work proves that wastewater-based epidemiology is a very valuable tool in developing countries where diagnostic tests for COVID-19 are limited.

Relationship between Physicochemical Characteristics and Pathogenic Leptospira in Urban Slum Waters.

Leptospirosis, a zoonosis caused by pathogenic Leptospira, primarily affects tropical, developing regions, especially communities without adequate sanitation. Outbreaks of leptospirosis have been linked with the presence of pathogenic Leptospira in water. In this study, we measured the physicochemical characteristics (temperature, pH, salinity, turbidity, electrical conductivity, and total dissolved solids (TDS)) of surface waters from an urban slum in Salvador, Brazil, and analyzed their associations with the presence and concentration of pathogenic Leptospira reported previously. We built logistic and linear regression models to determine the strength of association between physicochemical parameters and the presence and concentration of Leptospira. We found that salinity, TDS, pH, and type of water were strongly associated with the presence of Leptospira. In contrast, only pH was associated with the concentration of the pathogen in water. The study of physico-chemical markers can contribute to a better understanding of the occurrence of Leptospira in water and to the identification of sources of risk in urban slum environments.

Remoção simultânea de material orgânico, nitrogênio e fósforo em um reator em bateladas sequenciais com biofilme de leito móvel operado pelo processo anaeróbio-anóxico-óxico / Simultaneous removal of organic material, nitrogen and phosphorus in a reactor in batches of mobile bed biofilm sequencing by the anaerobic-anoxic-oxic process

RESUMO Neste estudo, foi avaliado o desempenho de um reator em bateladas sequenciais com biofilme de leito móvel operado pelo processo anaeróbio-anóxico-óxico (A2O), aplicado à remoção simultânea de material orgânico, nitrogênio e fósforo de esgoto sanitário. Utilizaram-se dois reatores com volume útil de 36 L cada, sendo que um deles recebeu anéis plásticos móveis do tipo Kaldnes®, com área superficial específica estimada em 310 m2/m3 que ocuparam 50% do volume útil do reator (denominado aqui de MBSBBR). O estudo foi conduzido com tempo de retenção de sólidos (TRS) de 12 dias, tempo de retenção hidráulico (TRH) de 6 horas, taxa de alimento/microrganismo (A/M) de 0,4 a 0,5 gDQO/SSV.d, oxigênio dissolvido (OD) na faixa de 0,3-0,8 mgO2/L e taxas de aplicação de carga orgânica, nitrogênio e fósforo de 47,2 gDQO/L.d, 5,4 gNTK/L.d e 0,4 gP/L.d, respectivamente. Os resultados de eficiência de remoção de demanda química de oxigênio (DQO), N-NH3 e fósforo foram de 91,1, 90,5 e 85,4% para o reator MBSBBR e de 89,5, 91,6 e 84,4% para o reator RBS, respectivamente. Os resultados do teste estatístico de ANOVA foram aplicados às principais variáveis estudadas, e os valores convergiram para valores de f observado < f crítico . Dessa forma, considera-se que houve similaridade de desempenho nos reatores MBSBBR e RBS. Conclui-se que a introdução do meio suporte não trouxe benefícios ao tratamento em termos de remoção de nutrientes. No entanto, o estudo mostrou que é possível de se obter elevada remoção de nitrogênio, em baixas concentrações de OD, o que se torna vantajoso para o tratamento de esgoto com elevada concentração de nitrogênio.

ABSTRACT In this study, the performance of a reactor in sequential batch with mobile bed biofilm operated by the anaerobic-anoxic-oxic (A2O) process, applied to the simultaneous removal of organic material, nitrogen and phosphorus from sanitary sewage was evaluated. Two reactors with a useful volume of 36 liters each were used, one of them receiving Kaldnes® type mobile plastic rings, with a specific surface area estimated at 310 m2/m3, which occupied 50% of the reactor's useful volume (MBSBBR). The study was conducted with 12-day solid retention time (SRT), 6 hour hydraulic retention time (HRT), food/microorganism (F/M) ratio of 0.4 to 0.5 gCOD/VSS.d, dissolved oxygen (DO) in the range of 0.3-0.8 mgO2/L and application rates of organic load, nitrogen and phosphorus of 47.2 gCOD/L.d, 5.4 gTNK/L.d and 0.4 gP/L.d, respectively. The efficiency of chemical oxygen demand (COD), N-NH3 and Phosphorus removal was of 91.1%, 90.5% and 85.4% for the MBSBBR reactor and 89.5%, 91.6% and 84.4% for the RBS reactor, respectively. The results of the statistical ANOVA test were applied to the main variables studied and the values converged to values of f observed < f critical . In this way, it is considered that there was a similarity of performance between the MBSBBR and RBS reactors. It is concluded that the introduction of the support medium did not bring benefits to the treatment in terms of nutrient removal. However, the study showed that it is possible to obtain high nitrogen removal at low concentrations of DO, which is advantageous for the sewage treatment with high nitrogen concentration.

Avaliação da multirresistência a antibióticos e produção de ESBL e carbapenemases em bacilos gram-negativos de efluente hospitalar e urbano / Evaluation of antibiotic multi-resistance and production of ESBL and carbapenemases in gram-negative bacilli of hospital and urban effluent

A multirresistência aos antibióticos observada em bacilos gram-negativos é um grave problema de saúde pública devido a alta morbidade e mortalidade apresentada, especialmente em instituições assistenciais de saúde. Como consequência do intenso uso de antibióticos, a multirresistência a esses fármacos é principalmente mediada por enzimas hidrolisantes, onde destaca-se as enzimas ?-lactamases, principal mecanismo de resistência aos ?-lactâmicos verificado em bacilos gram-negativos. Os esgotos de origem hospitalar e de estações de tratamento de esgoto (ETE) são considerados como reservatórios de bactérias multirresistentes pela presença de antibióticos que as selecionam e por favorecem a transmissão de determinantes de resistência. Nesse sentido, o presente estudo objetivou avaliar a multirresistência a antibióticos e a produção de enzimas ?-lactamases em bacilos gram-negativos isolados de efluente hospitalar e da estação de tratamento de esgoto, na cidade de Ribeirão Preto, SP. No hospital terciário, amostras de esgotos foram coletadas dos ambulatórios, das enfermarias e da junção do esgoto hospitalar. Na ETE, amostras foram coletadas na caixa de entrada do esgoto bruto e após ao tratamento. Dez microlitros foram semeados em ágar MacConkey, SalmonellaShigella, Cetrimide e TCBS e a identificação dos bacilos gram-negativos foi realizada pelo kit Bactray®. O teste de susceptibilidade aos antibióticos foi realizado pelo método de discodifusão em ágar. A detecção fenotípica de bacilos produtores de ESBL foi realizada pelos testes de sinergia de disco-duplo e disco combinado com ácido clavulânico, e para detecção de isolados produtores de carbapenemases foi utilizado os testes de disco combinado com ácido fenilborônico e EDTA e o teste Blue Carba. A PCR foi utilizada para amplificação dos genes codificadores de ESBL e carbapenemases. No total, 45 bacilos gram-negativos foram isolados, sendo as espécies Klebsiella pneumoniae e Pseudomonas aeruginosa as de maiores prevalências. Ampla resistência foi verificada aos antibióticos ?-lactâmicos, sendo a resistência ao aztreonam, a cefepime e a cefotaxima mais expressiva nos isolados do esgoto hospitalar, com diferenças estatisticamente significante (p<0,05). O fenótipo multidroga resistente foi atribuído a 33,3%, nos isolados exclusivamente do esgoto hospitalar, com diferença estatisticamente significante (p = 0,0025) em relação aos isolados do esgoto da ETE. Genes de ?-lactamases foram encontrados em 35,6% das bactérias, sendo o blaKPC e blaTEM os de maiores ocorrências, ambos em 17,8% dos isolados, e os genes blaSHV e blaCTX-M em 13,3% e 8,9%. Somente em um isolado de Enterobacter cloacae no esgoto tratado da ETE foi identificado o gene blaSHV, os demais isolados portadores dos genes de ?-lactamases foram encontrados no esgoto hospitalar. Os dados obtidos neste estudo são importantes levando em consideração que no Brasil o esgoto hospitalar pode ser lançado in natura na rede coletora municipal, no entanto, acredita-se que tal permissão favorece a disseminação da multirresistência bacteriana, posto que, os resultados demonstram alta frequência de bactérias portadoras de genes de resistência a antibióticos no esgoto hospitalar estudado. Assim, a implementação do tratamento de efluentes hospitalares, especialmente os de hospitais terciários, e adicionalmente ao tratamento da ETE evitaria a propagação dessas bactérias no ambiente e de impactar negativamente os recursos hídricos

Antibiotic multi-resistance observed in Gram-negative bacilli is a serious public health problem due to high morbidity and mortality, especially in health care institutions. As a consequence of the intense use of antibiotics, multi-resistance to these drugs is mainly mediated by hydrolyzing enzymes, in which ?-lactamases, the main ?-lactam resistance mechanism observed in Gramnegative bacilli, are prominent. Hospital sewage and wastewater treatment plants (WWTP) are considered reservoirs of multiresistant bacteria by the presence of antibiotics that select these bacteria and favor the transmission of resistance determinants. In this sense, the present study aimed to evaluate the antibiotics multi-resistance and the production of ?-lactamase enzymes in Gram-negative bacilli isolated from hospital effluent and the wastewater treatment plants in Ribeirão Preto city, SP. In the tertiary hospital, sewage samples from the outpatient clinics, rooms patients and the hospital sewage junction were collected. In the WWTP, raw and treated sewage were collected. Ten microliters were seeded on MacConkey, Salmonella-Shigella, Cetrimide and TCBS agar and the identification of Gram-negative bacilli was performed by the Bactray® kit. Antibiotic susceptibility test was performed by agar-diffusion method. Phenotypic detection of ESBL-producing bacilli was performed by double-disc and discsynergy tests combined with clavulanic acid, and for the detection of carbapenemase-producing isolates the combined disk tests with phenylboronic acid and EDTA and Blue Carba test were used. PCR amplification of ESBL and carbapenemases-encoding genes was used. In total, 45 Gram-negative bacilli were isolated, and Klebsiella pneumoniae and Pseudomonas aeruginosa being the most prevalent. Extensive resistance was verified to ?-lactam antibiotics and resistance to aztreonam, cefepime and cefotaxime was more pronounced in hospital sewage isolates, with statistically significant differences (p<0.05). Multidrug-resistant phenotype was attributed to 33.3% in isolates exclusively from hospital sewage, with a statistically significant difference (p = 0.0025) in relation to the sewage isolates from the WWTP. ?-lactamase genes were found in 35.6% of the bacteria, with blaKPC and blaTEM having the highest occurrences, both in 17.8% of the isolates, and the blaSHV and blaCTX-M genes in 13.3% and 8, 9%. Only in an isolate of Enterobacter cloacae in the treated sewage from WWTP was the blaSHV gene identified, the other isolates carrying the ?-lactamases genes were found in hospital sewage. The data obtained in this study are important considering that in Brazil the hospital sewage can be released in nature in municipal collection network, however, it is believed that such permission favors the dissemination of bacterial multi-resistance, since, the results show high frequency of bacteria carrying antibiotic resistance genes in the hospital sewer studied. Thus, the implementation of treatment of hospital effluents, especially those in tertiary hospitals, and in addition to the treatment of WWTP would prevent the spread of these bacteria in the environment and negatively impact water resources

Wastewater-based epidemiology in low Human Development Index states: bias in consumption monitoring of illicit drugs.

Wastewater-based epidemiology is a promising approach worldwide, and its application is currently being developed in non-advanced economies. This technology, based on known toxicokinetic data initially used to detect illicit drugs in well-managed and maintained local sewer networks, has been extended to assess other products such as pesticides, alcohol, flame retardants, nicotine, and other substances. This technology is also used in countries with non-advanced economies. The present review aims to support future wastewater-based epidemiology in such countries by providing toxicokinetic data for locally used narcotic drugs that are expected or known to be emerging in developed countries, outlining the excretion differences due to human polymorphism, and summarising the practical obstacles due to the coverage, maintenance efficiency, or type of local sewage network.Case study feedback from Martinique is presented as an example; the Martinique field study complies with the Organisation for Economic Co-operation and Development standards for health issues, but not with regard to population and urban dynamics.

Caracterização da biota de protozoários e sua função depurativa na lagoa de estabilização da estação de tratamento de esgoto de Bandeirantes – PR / Characterization of the protozoan biota and its depurating function in the stabilization pond of the Bandeirantes water treatment plant, Paraná State

Os protozoários são, usualmente, maiores que as bactérias e podem se alimentar das mesmas. Isto faz com que os protozoários constituam-se em importantes degraus na pirâmide alimentar, possibilitando que organismos maiores se alimentem indiretamente das bactérias que, de outra forma, seriam um alimento inacessível (VON SPERLING, 1996). Este estudo objetivou a caracterização físico-química e microbiológica da lagoa de estabilização da ETE Bandeirantes - PR, analisando sua inter-relação e nível de estratificação, relacionando os parâmetros físico-químicos e microbiológicos, a variação populacional dos protozoários frente a valores de matéria orgânica e microbióta bacteriana do esgoto e dos vários estratos da lagoa anaeróbia. A identificação de protozoários foi feita conforme metodologia empregada por Pace e Orcutt (1981) e Foissnere Berger (1996). As análises físico-químicas foram realizadas conforme metodologia padronizada por Clesceri et al. (2000); e as análises microbiológicas foram realizadas por metodologia padronizada conforme CETESB, (NT.L5.214), 1992; CETESB, (NT. L5.201), 1986; CETESB, (NT.L5.221), 1984. As coletas e análises foram realizadas em triplicata, no mês de outubro de 2003. A análise qualitativa do zooplâncton revelou a presença de onze gêneros de ciliados e organismos da classe nematoda distribuídos em diferentes pontos e estratos. A distribuição aleatória do zooplâncton está relacionada com parâmetros físico-químicos e valores quantitativos de bactérias eterotróficas, coliformes totais e fecais. O gênero Chilodontopsis foi o protozoário mais encontrado e estava presente em pontos com altos valores de contagem de bactérias, o que denota sua característica ecológica de preferência alimentar por bactérias, conforme Foissner e Berger (1996).

The protozoans are usually bigger than the bacteria and can feed themselves of the same ones. This consequence is that the protozoan consists in an important step in the alimentary pyramid, making possible that bigger organisms feeds the bacteria it self indirectly which, in the other hand, would be an in accessible food form (VON SPERLING, 1996). This study aim characterize microbiological physicist-chemistry profile in a lagoon of stabilization of the Sewer Plant Bandeirantes - PR, analyzing its interrelation and level of stratification, relating the parameters microbiological physicistchemistries and the protozoa’s population variation front the values of bacterial and organic substance of the sewer, and some stratus of the anaerobic lagoon. The identification of protozoan was made in agreement the methodology used for Pace and Orcutt (1981) and Foissner and Berger (1996). The physicist-chemistries analysis had been carried through in agreement standardized methodology for Clesceri et al. (2000); e the microbiological analysis had been carried through by standardized methodology, as CETESB (NT.L5.214), 1992; CETESB, (NT L5.201), 1986; CETESB,(NT.L5.221), 1984. The samplings and analysis were realized intriplicate in October of 2003. The qualitative analysis of zooplankton disclosed to the presence of eleven kinds of ciliates organisms and Nematoda class organisms distributed in different points and stratus. The random distribution of zooplankton is related with physicistchemistries parameters and quantitative values of heterotrophic bacteria, total and fecal coliformes. The Chilodontopsis sort was the greater found and was present in points with high values of counting of bacteria, what it denotes its ecological characteristic of alimentary preference for bacteria, as referenced by Foissner and Berger (1996).