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The role of community participation for sustainable integrated neglected tropical diseases and water, sanitation and hygiene intervention programs: A pilot project in Tanzania.

Soc Sci Med; 202: 28-37, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29501716


Strategies aimed at reducing the prevalence of neglected tropical diseases (NTDs) in Tanzania including those attributed to water, sanitation and hygiene (WASH) problems have been largely top-down in nature. They have focused on strengthening the governance of NTD-WASH programs by integrating different vertical disease programs and improving the efficiency of report-generation. In this paper, we argue for community participation as an effective strategy for developing sustainable village health governance. We present the results of a pilot undertaken between November 2015 and April 2016 in which we adopted a mixed methods case study approach to implement an Enhanced Development Governance (EDG) model using existing village governance structures. Our results show that the EDG model was associated with a statistically significant reduction in the prevalence of schistosomiasis and diarrhoea, and has led to an increase in awareness of WASH interventions for sustaining gains in NTD control. We identify five key social processes enacted by the EDG model that have led to improved health benefits related to frequency of meetings and attendance, promotion of health and sanitation awareness, income-generating activities, self-organising capabilities, and interaction between village bodies. These findings hold important implications for conceptualising the role of community participation in sustaining NTD-WASH intervention programs and for sensitising institutional and policy reform.

Industrial wastewater treatment with a bioelectrochemical process: assessment of depuration efficiency and energy production.

Water Sci Technol; 77(1-2): 134-144, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29339612


Development of renewable energy sources, efficient industrial processes, energy/chemicals recovery from wastes are research issues that are quite contemporary. Bioelectrochemical processes represent an eco-innovative technology for energy and resources recovery from both domestic and industrial wastewaters. The current study was conducted to: (i) assess bioelectrochemical treatability of industrial (dairy) wastewater by microbial fuel cells (MFCs); (ii) determine the effects of the applied organic loading rate (OLR) on MFC performance; (iii) identify factors responsible for reactor energy recovery losses (i.e. overpotentials). For this purpose, an MFC was built and continuously operated for 72 days, during which the anodic chamber was fed with dairy wastewater and the cathodic chamber with an aerated mineral solution. The study demonstrated that industrial effluents from agrifood facilities can be treated by bioelectrochemical systems (BESs) with >85% (average) organic matter removal, recovering power at an observed maximum density of 27 W m . Outcomes were better than in previous (shorter) analogous experiences, and demonstrate that this type of process could be successfully used for dairy wastewater with several advantages.

How immediate and significant is the outcome of training on diversified diets, hygiene and food safety? An effort to mitigate child undernutrition in rural Malawi.

Public Health Nutr; 21(6): 1156-1166, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29338801


OBJECTIVE: The present study examined the impacts of training on nutrition, hygiene and food safety designed by the Nutrition Working Group, Child Survival Collaborations and Resources Group (CORE). DESIGN: Adapted from the 21d Positive Deviance/Hearth model, mothers were trained on the subjects of appropriate complementary feeding, water, sanitation and hygiene (WASH) practices, and aflatoxin contamination in food. To assess the impacts on child undernutrition, a randomised controlled trial was implemented on a sample of 179 mothers and their children (<2 years old) in two districts of Malawi, namely Mzimba and Balaka. Settings A 21d intensive learning-by-doing process using the positive deviance approach. SUBJECTS: Malawian children and mothers. RESULTS: Difference-in-difference panel regression analysis revealed that the impacts of the comprehensive training were positive and statistically significant on the Z-scores for wasting and underweight, where the effects increased constantly over time within the 21d time frame. As for stunting, the coefficients were not statistically significant during the 21d programme, although the level of significance started increasing in 2 weeks, indicating that stunting should also be alleviated in a slightly longer time horizon. CONCLUSIONS: The study clearly suggests that comprehensive training immediately guides mothers into improved dietary and hygiene practices, and that improved practices take immediate and progressive effects in ameliorating children's undernutrition.

Determination of Appropriate Service Delivery Level for Quantitative Attributes of Household Toilets in Rural Settlements of India from Users' Perspective.

Environ Manage; 61(4): 637-649, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29330609


Improvement of quality of sanitation services in rural settlements is an important development goal in developing countries including India and accordingly several strategies are adopted which promote the demand and use of household toilets through creating awareness and providing subsidies to poor people for construction of household toilets with service-level standards specified from experts' perspective. In many cases, users are unsatisfied with the quality of toilets constructed using subsidies and the same remain unused. Users' satisfaction depends on their perceptions of service quality of individual attributes and overall service quality of the household toilets, which is an important determinant of sustainability and sustained use of toilets. This study aims to assess and benchmark the appropriate service delivery level for quantitative attributes of rural household toilets based on user perception. The service quality is determined with the help of level of service (LOS) scales developed using successive interval scaling technique, the zone of tolerance (ZOT), and users satisfaction level (USL) which relates service delivery levels with user satisfaction directly. The study finds that the service quality of most of the attributes of household toilets constructed using subsidies is perceived as poor. The results also suggest that most of the users expect to have a toilet with the service level of attributes ranging between LOS A and LOS B.

Enhancing nitrogen removal efficiency in a dyestuff wastewater treatment plant with the IFFAS process: the pilot-scale and full-scale studies.

Water Sci Technol; 77(1-2): 70-78, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29339605


The activated sludge (AS) process is widely applied in dyestuff wastewater treatment plants (WWTPs); however, the nitrogen removal efficiency is relatively low and the effluent does not meet the indirect discharge standards before being discharged into the industrial park's WWTP. Hence it is necessary to upgrade the WWTP with more advanced technologies. Moving bed biofilm processes with suspended carriers in an aerobic tank are promising methods due to enhanced nitrification and denitrification. Herein, a pilot-scale integrated free-floating biofilm and activated sludge (IFFAS) process was employed to investigate the feasibility of enhancing nitrogen removal efficiency at different hydraulic retention times (HRTs). The results showed that the effluent chemical oxygen demand (COD), ammonium nitrate (NH -N) and total nitrogen (TN) concentrations of the IFFAS process were significantly lower than those of the AS process, and could meet the indirect discharge standards. PCR-DGGE and FISH results indicated that more nitrifiers and denitrifiers co-existed in the IFFAS system, promoting simultaneous nitrification and denitrification. Based on the pilot results, the IFFAS process was used to upgrade the full-scale AS process, and the effluent COD, NH -N and TN of the IFFAS process were 91-291 mg/L, 10.6-28.7 mg/L and 18.9-48.6 mg/L, stably meeting the indirect discharge standards and demonstrating the advantages of IFFAS in dyestuff wastewater treatment.

Culturally appropriate organization of water and sewerage projects built through public private partnerships.

PLoS One; 12(12): e0188905, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29200432


This paper contributes to the pursuit of socially sustainable water and sanitation infrastructure for all people by discovering statistically robust relationships between Hofstede's dimensions of cross-cultural comparison and the choice of contract award types, project type, and primary revenue sources. This analysis, which represents 973 projects distributed across 24 low- and middle-income nations, uses a World Bank dataset describing high capital cost water and sewerage projects funded through private investment. The results show that cultural dimensions explain variation in the choice of contract award types, project type, and primary revenue sources. These results provide empirical evidence that strategies for water and sewerage project organization are not culturally neutral. The data show, for example, that highly individualistic contexts are more likely to select competitive contract award types and to depend on user fees to provide the primary project revenue stream post-construction. By selecting more locally appropriate ways to organize projects, project stakeholders will be better able to pursue the construction of socially sustainable water and sewerage infrastructure.

Optimizing household survey methods to monitor the Sustainable Development Goals targets 6.1 and 6.2 on drinking water, sanitation and hygiene: A mixed-methods field-test in Belize.

PLoS One; 12(12): e0189089, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29216244


BACKGROUND: The Sustainable Development Goals (SDGs) require household survey programmes such as the UNICEF-supported Multiple Indicator Cluster Surveys (MICS) to enhance data collection to cover new indicators. This study aims to evaluated methods for assessing water quality, water availability, emptying of sanitation facilities, menstrual hygiene management and the acceptability of water quality testing in households which are key to monitoring SDG targets 6.1 and 6.2 on drinking Water, Sanitation and Hygiene (WASH) and emerging issues. METHODS: As part of a MICS field test, we interviewed 429 households and 267 women age 15-49 in Stann Creek, Belize in a split-sample experiment. In a concurrent qualitative component, we conducted focus groups with interviewers and cognitive interviews with respondents during and immediately following questionnaire administration in the field to explore their question comprehension and response processes. FINDINGS: About 88% of respondents agreed to water quality testing but also desired test results, given the potential implications for their own health. Escherichia coli was present in 36% of drinking water collected at the source, and in 47% of samples consumed in the household. Both questions on water availability necessitated probing by interviewers. About one quarter of households reported emptying of pit latrines and septic tanks, though one-quarter could not provide an answer to the question. Asking questions on menstrual hygiene was acceptable to respondents, but required some clarification and probing. CONCLUSIONS: In the context of Belize, this study confirmed the feasibility of collecting information on the availability and quality of drinking water, emptying of sanitation facilities and menstrual hygiene in a multi-purpose household survey, indicating specific areas to improve question formulation and field protocols. Improvements have been incorporated into the latest round of MICS surveys which will be a major source of national data for monitoring of SDG targets for drinking water, sanitation and hygiene and emerging issues for WASH sector programming.

Evaluating the efficiency of carbon utilisation via bioenergetics between biological aerobic and denitrifying phosphorus removal systems.

PLoS One; 12(10): e0187007, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29065157


There are two biological systems available for removing phosphorus from waste water, conventional phosphorus removal (CPR) and denitrifying phosphorus removal (DPR) systems, and each is characterized by the type of sludge used in the process. In this study, we compared the characteristics associated with the efficiency of carbon utilization between CPR and DPR sludge using acetate as a carbon source. For DPR sludge, the heat emitted during the phosphorus release and phosphorus uptake processes were 45.79 kJ/mol e- and 84.09 kJ/mol e-, respectively. These values were about 2 fold higher than the corresponding values obtained for CPR sludge, suggesting that much of the energy obtained from the carbon source was emitted as heat. Further study revealed a smaller microbial mass within the DPR sludge compared to CPR sludge, as shown by a lower sludge yield coefficient (0.05 gVSS/g COD versus 0.36 gVSS/g COD), a result that was due to the lower energy capturing efficiency of DPR sludge according to bioenergetic analysis. Although the efficiency of anoxic phosphorus removal was only 39% the efficiency of aerobic phosphorus removal, the consumption of carbon by DPR sludge was reduced by 27.8% compared to CPR sludge through the coupling of denitrification with dephosphatation.

Constructed wetlands and solar-driven disinfection technologies for sustainable wastewater treatment and reclamation in rural India: SWINGS project.

Water Sci Technol; 76(6): 1474-1489, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28953474


SWINGS was a cooperation project between the European Union and India, aiming at implementing state of the art low-cost technologies for the treatment and reuse of domestic wastewater in rural areas of India. The largest wastewater treatment plant consists of a high-rate anaerobic system, followed by vertical and horizontal subsurface flow constructed wetlands with a treatment area of around 1,900 m and a final step consisting of solar-driven anodic oxidation (AO) and ultraviolet (UV) disinfection units allowing direct reuse of the treated water. The implementation and operation of two pilot plants in north (Aligarh Muslim University, AMU) and central India (Indira Gandhi National Tribal University, IGNTU) are shown in this study. The overall performance of AMU pilot plant during the first 7 months of operation showed organic matter removal efficiencies of 87% total suspended solids, 95% 5-day biological oxygen demand (BOD ) and 90% chemical oxygen demand, while Kjeldahl nitrogen removal reached 89%. The UV disinfection unit produces water for irrigation and toilet flushing with pathogenic indicator bacteria well below WHO guidelines. On the other hand, the AO disinfection unit implemented at IGNTU and operated for almost a year has been shown to produce an effluent of sufficient quality to be reused by the local population for agriculture and irrigation.

Estimation of the removal efficiency of heavy metals and nutrients from ecological drainage ditches treating town sewage during dry and wet seasons.

Environ Monit Assess; 189(9): 434, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28779427


Vegetated drainage ditches (ecological drainage ditches, EDD) are commonly used for the treatment of nutrients, suspended solids, and pesticides, from agricultural lands and aquaculture effluent. However, their effectiveness to remove heavy metals/metalloids (HM/Ms) and fate remains largely unexplored. In addition, there exists some uncertainty concerning the performance of the EDD in treating HM/Ms. This study presents a thorough assessment on the removal efficiencies of HM/Ms and identifies the parameters affecting the HM/Ms removal process in the EDD receiving primary domestic sewage for 13 years. The mean concentrations of the studied HM/Ms in sediments were lower than those reported in the aquatic ecosystems affected by coal-mine drainage and industrial wastewaters. The results also showed that the concentrations of the selected HM/Ms in ditch sediment were generally far higher than the soil background values of Sichuan basin. Concentrations of all the studied HM/Ms and nutrients in water entering the EDD were significantly higher than the effluent. The annual mean removal efficiencies of Ni, Cu, Cr, Zn, Cd, Pb, As, Fe, Al, Mn, N, and P in the ecological drainage ditch were 50.6, 56.1, 63.3, 79.3, 67.5, 80.1, 60.3, 52.6, 19.8, 24.3, 72.0, and 59.7%, respectively. The study also displayed that dissolved oxygen levels at the outlet were significantly (p < 0.001) higher after passing into the EDD system. The pH was kept at neutral or alkaline. Removal of HM/Ms and nutrients was seasonal, generally peaking in the growing season. Sedimentation was the major mechanism removing HM/Ms within the EDD system. EDD was found to possess a favorable influence at mitigating HM/Ms and nutrients in situ and can be successfully utilized to resolve this type of environmental pollution.

Greenlandic water and sanitation-a context oriented analysis of system challenges towards local sustainable development.

Artigo em Inglês | MEDLINE | ID: mdl-28849342


Today, as Greenland focuses on more economic and cultural autonomy, the continued development of societal infrastructure systems is vital. At the same time, pressure is put on the systems by a lack of financial resources and locally based professional competences as well as new market-based forms of organization. Against this background, the article discusses the challenges facing Greenland's self-rule in relation to further develop the existing water and wastewater systems so that they can contribute to the sustainable development of Greenland. The article reviews the historical development of the water supply and wastewater system. This leads to an analysis of the sectorisation, which in recent decades has reorganized the Greenlandic infrastructures, and of how this process is influencing local sustainable development. The article discusses the socio-economic and human impacts and points to the need for developing the water and sanitation system to support not only hygiene and health, but also local sustainable development.

Consumer Perceptions of the Safety of Ready-to-Eat Foods in Retail Food Store Settings.

J Food Prot; 80(8): 1364-1377, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28722484


To better understand how consumers perceive food safety risks in retail food store settings, a survey was administered to 1,041 nationally representative participants who evaluated possible food safety risks depicted in selected photographs and self-reported their perceptions, attitudes, and behaviors. Participants were shown 12 photographs taken at retail stores portraying either commonly perceived or actual food safety contributing factors, such as cross-contamination, product and equipment temperatures, worker hygiene, and/or store sanitation practices. Participants were then asked to specifically identify what they saw, comment as to whether what they saw was safe or unsafe, and articulate what actions they would take in response to these situations. In addition to the survey, focus groups were employed to supplement survey findings with qualitative data. Survey respondents identified risk factors for six of nine actual contributing factor photographs >50% of the time: poor produce storage sanitation (86%, n = 899), cross-contamination during meat slicing (72%, n = 750), bare-hand contact of ready-to-eat food in the deli area (67%, n = 698), separation of raw and ready-to-eat food in the seafood case (63%, n = 660), cross-contamination from serving utensils in the deli case (62%, n = 644), and incorrect product storage temperature (51%, n = 528). On a scale of 1 to 5, where 1 was very unsafe and 5 was very safe, a significant difference was found between average risk perception scores for photographs of actual contributing factors (score of ca. 2.5) and scores for photographs of perceived contributing factors (score of ca. 2.0). Themes from the focus groups supported the results of the survey and provided additional insight into consumer food safety risk perceptions. The results of this study inform communication interventions for consumers and retail food safety professionals aimed at improving hazard identification.

Effect of reflux ratio on nitrogen removal in a novel upflow microaerobic sludge reactor treating piggery wastewater with high ammonium and low COD/TN ratio: Efficiency and quantitative molecular mechanism.

Bioresour Technol; 243: 922-931, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28738547


A novel upflow microaerobic sludge reactor (UMSR) was constructed to treat manure-free piggery wastewater with high NH -N and low COD/TN ratio. In the light of the potential effect of effluent reflux ratio (RR) on nitrogen removal, performance of the UMSR was evaluated at 35°C and hydraulic retention time 8h with RR decreased from 45 to 25 by stages. A COD, NH -N and TN removal of above 77.1%, 80.0% and 86.6%, respectively, was kept with a RR over 35. To get an effluent of TN not more than 80mg/L with a TN load removal above 0.88kg/(m ·d), the RR should be at least 34. Real-time quantitative polymerase chain reaction of functional bacteria revealed that the RR of less than 34 stimulated ammonium oxidation but badly inhibited anammox, the dominant nitrogen removal pathway, resulting in the remarkable decrease of nitrogen removal in the reactor.

Sustainable pyrolytic sludge-char preparation on improvement of closed-loop sewage sludge treatment: Characterization and combined in-situ application.

Chemosphere; 184: 1043-1053, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28662548


Aiming at closed-loop sustainable sewage sludge treatment, an optimal and economical pyrolytic temperature was found at 400-450 °C considering its pyrolysis efficiency of 65%, fast cracking of hydrocarbons, proteins and lipids and development of aromatized porous structure. Fourier-transform infrared (FTIR) and X-ray diffraction (XRD) tests demonstrated the development of adsorptive functional groups and crystallographic phases of adsorptive minerals. The optimal sludge-char, with a medium specific surface area of 39.6 m g and an iodine number of 327 mgI g , performed low heavy metals lixiviation. The application of sludge-char in raw sewage could remove 30% of soluble chemical oxygen demand (SCOD), along with an acetic acid adsorption capacity of 18.0 mg g . The developed mesopore and/or macropore structures, containing rich acidic and basic functional groups, led to good biofilm matrices for enhanced microbial activities and improved autotrophic nitrification in anoxic stage of an A/O reactor through adsorbed extra carbon source, and hence achieved the total nitrogen (TN) removal up to 50.3%. It is demonstrated that the closed-loop sewage sludge treatment that incorporates pyrolytic sludge-char into in-situ biological sewage treatment can be a promising sustainable strategy by further optimization.

Piloting water quality testing coupled with a national socioeconomic survey in Yogyakarta province, Indonesia, towards tracking of Sustainable Development Goal 6.

Int J Hyg Environ Health; 220(7): 1141-1151, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28743592


There remains a pressing need for systematic water quality monitoring strategies to assess drinking water safety and to track progress towards the Sustainable Development Goals (SDG). This study incorporated water quality testing into an existing national socioeconomic survey in Yogyakarta province, Indonesia; the first such study in Indonesia in terms of SDG tracking. Multivariate regression analysis assessed the association between faecal and nitrate contamination and drinking water sources household drinking water adjusted for wealth, education level, type of water sources and type of sanitation facilities. The survey observed widespread faecal contamination in both sources for drinking water (89.2%, 95%CI: 86.9-91.5%; n=720) and household drinking water (67.1%, 95%CI: 64.1-70.1%; n=917) as measured by Escherichia coli. This was despite widespread improved drinking water source coverage (85.3%) and commonly self-reported boiling practices (82.2%). E.coli concentration levels in household drinking water were associated with wealth, education levels of a household head, and type of water source (i.e. vender water or local sources). Following the proposed SDG definition for Target 6.1 (water) and 6.2 (sanitation), the estimated proportion of households with access to safely managed drinking water and sanitation was 8.5% and 45.5%, respectively in the study areas, indicating substantial difference from improved drinking water (82.2%) and improved sanitation coverage (70.9%) as per the MDGs targets. The greatest contamination and risk factors were found in the poorest households indicating the urgent need for targeted and effective interventions here. There is suggested evidence that sub-surface leaching from on-site sanitation adversely impacts on drinking water sources, which underscores the need for further technical assistance in promoting latrine construction. Urgent action is still needed to strengthen systematic monitoring efforts towards tracking SDG Goal 6.

Novel Stokesian Metrics that Quantify Collision Efficiency, Floc Strength, and Discrete Settling Behavior.

Water Environ Res; 89(7): 586-597, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28641670


Novel parameters were developed to predict the effluent quality and settling behavior in clarifiers that cannot conventionally be achieved using either the conventional flux theory or overflow rates. Simple batch experiments based on the critical settling velocity (CSV) selection were used as the basis for the development of three novel parameters: intrinsic settling classes (ISC), threshold of flocculation/flocculation limitation (TOF/α), and floc strength. ISC was proven to accurately (±2%) determine the granule fraction and discrete particle distribution. TOF quantified the minimum solids concentration needed to form large flocs and was directly linked to collision efficiency. In hybrid systems, an exponential fitting on a CSV matrix was proposed to quantify the collision efficiency of flocs (α). Shear studies were conducted to quantify floc strength. The methods were applied to a wide spectrum of sludge types to show the broad applicability and sensitivity of the novel methods.

Enabling the sustainable Faecal Sludge Management service delivery chain-A case study of dense settlements in Kigali, Rwanda.

Int J Hyg Environ Health; 220(6): 960-973, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28596087


The lack of access to basic sanitation is a global concern and alarmingly prevalent in low- and middle- income countries. In the densely populated settlements of these countries, on-site sanitation systems are usually the only feasible option because dwellers there have no sewers in place to connect to. Using on-site sanitation facilities results in an accumulation of faecal sludge which needs to be properly managed to ensure the well-being of the users as well as the surrounding environment. Unfortunately, often the conditions for faecal sludge management (FSM) within dense settlements are adverse and thus hamper sustainable FSM. We use the normative framework of the FSM enabling environment to gather empirical evidence from densely populated settlements of Kigali city in Rwanda to examine current FSM practices and the extent to which these are being influenced and affected by the setting within which they are taking place. The analysis of the study findings confirms that the existing conditions for FSM in these settlements are inadequate. The specific constraints that hinder the achievement of sustainable FSM include limited government focus on the sanitation sector, high turnover of staff in relevant government institutions, pit sludge management is not placed on the sanitation projects agenda, the existing relevant bylaws are not pro-poor oriented, a lack of clear responsibilities, a lack of relevant local professional training opportunities, unaffordability of FSM services and an inhibition to discuss FSM. Drawing on the involved stakeholders' own perceptions and suggestions, we identify possible approaches to overcome the identified constraints and to allow all actors in the FSM chain to contribute effectively to the management of faecal sludge in densely populated low-income urban settlements. Finally, our study also presents a contribution to the theoretical conceptualisation of the enabling environment for sustainable FSM.

Bacteriophage removal efficiency as a validation and operational monitoring tool for virus reduction in wastewater reclamation: Review.

Water Res; 121: 258-269, 2017 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-28551509


The multiple-barrier concept is widely employed in international and domestic guidelines for wastewater reclamation and reuse for microbiological risk management, in which a wastewater reclamation system is designed to achieve guideline values of the performance target of microbe reduction. Enteric viruses are one of the pathogens for which the target reduction values are stipulated in guidelines, but frequent monitoring to validate human virus removal efficacy is challenging in a daily operation due to the cumbersome procedures for virus quantification in wastewater. Bacteriophages have been the first choice surrogate for this task, because of the well-characterized nature of strains and the presence of established protocols for quantification. Here, we performed a meta-analysis to calculate the average log reduction values (LRVs) of somatic coliphages, F-specific phages, MS2 coliphage and T4 phage by membrane bioreactor, activated sludge, constructed wetlands, pond systems, microfiltration and ultrafiltration. The calculated LRVs of bacteriophages were then compared with reported human enteric virus LRVs. MS2 coliphage LRVs in MBR processes were shown to be lower than those of norovirus GII and enterovirus, suggesting it as a possible validation and operational monitoring tool. The other bacteriophages provided higher LRVs compared to human viruses. The data sets on LRVs of human viruses and bacteriophages are scarce except for MBR and conventional activated sludge processes, which highlights the necessity of investigating LRVs of human viruses and bacteriophages in multiple treatment unit processes.

A high-efficiency denitrification bioreactor for the treatment of acrylonitrile wastewater using waterborne polyurethane immobilized activated sludge.

Bioresour Technol; 239: 472-481, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28544987


The performance of a laboratory-scale, high-efficiency denitrification bioreactor (15L) using activated sludge immobilized by waterborne polyurethane in treating acrylonitrile wastewater with high concentration of nitrate nitrogen (249mg/L) was investigated. The bioreactor was operated at 30°C for 220days. Batch denitrification experiments showed that the optimal operation parameters were C/NO -N molar ratio of 2.0 using sodium acetate as electron donor and carrier filling rate of 20% (V/V) in the bioreactor. Stable performance of denitrification was observed with a hydraulic retention time of 30 to 38h. A volumetric removal rate up to 2.1kgN/m ·d was achieved with a total nitrogen removal efficiency of 95%. Pyrosequencing results showed that Rhodocyclaceae and Pseudomonadaceae were the dominant bacterial families in the immobilized carrier and bioreactor effluent. The overall microbial diversity declined as denitrifiers gradually dominated and the relative abundance of other bacteria decreased along with testing time.

Examining the safety of menstrual cups among rural primary school girls in western Kenya: observational studies nested in a randomised controlled feasibility study.

BMJ Open; 7(4): e015429, 2017 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-28473520


OBJECTIVE: Examine the safety of menstrual cups against sanitary pads and usual practice in Kenyan schoolgirls. DESIGN: Observational studies nested in a cluster randomised controlled feasibility study. SETTING: 30 primary schools in a health and demographic surveillance system in rural western Kenya. PARTICIPANTS: Menstruating primary schoolgirls aged 14-16 years participating in a menstrual feasibility study. INTERVENTIONS: Insertable menstrual cup, monthly sanitary pads or 'usual practice' (controls). OUTCOME MEASURES: vaginal colonization, growth on sampled used cups, toxic shock syndrome or other adverse health outcomes. RESULTS: Among 604 eligible girls tested, no adverse event or TSS was detected over a median 10.9 months follow-up. prevalence was 10.8%, with no significant difference over intervention time or between groups. Of 65 positives at first test, 49 girls were retested and 10 (20.4%) remained positive. Of these, two (20%) sample isolates tested positive for toxic shock syndrome toxin-1; both girls were provided pads and were clinically healthy. Seven per cent of cups required replacements for loss, damage, dropping in a latrine or a poor fit. Of 30 used cups processed for growth, 13 (37.1%, 95% CI 21.1% to 53.1%) had growth. growth was greatest in newer compared with established users (53%vs22.2%, p=0.12). CONCLUSIONS: Among this feasibility sample, no evidence emerged to indicate menstrual cups are hazardous or cause health harms among rural Kenyan schoolgirls, but large-scale trials and post-marketing surveillance should continue to evaluate cup safety.
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