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Access to safe drinking water is a human right, crucial to combat inequalities, reduce poverty and allow sustainable development. In many areas of the world, however, this right is not guaranteed, in part because of the lack of easily deployable diagnostic tools. Low-cost and simple methods to test water supplies onsite can protect vulnerable communities from the impact of contaminants in drinking water. Ideally such devices would also be easy to dispose of so as to leave no trace, or have a detrimental effect on the environment. To this aim, we here report the first paper microbial fuel cell (pMFC) fabricated by screen-printing biodegradable carbon-based electrodes onto a single sheet of paper, and demonstrate its use as a shock sensor for bioactive compounds (e.g. formaldehyde) in water. We also show a simple route to enhance the sensor performance by folding back-to-back two pMFCs electrically connected in parallel. This promising proof of concept work can lead to a revolutionizing way of testing water at point of use, which is not only green, easy-to-operate and rapid, but is also affordable to all.

As a cost-effective alternative to silver nanoparticles, we have investigated the use of copper nanoparticles in paper filters for point-of-use water purification. This work reports an environmentally benign method for the direct in situ preparation of copper nanoparticles (CuNPs) in paper by reducing sorbed copper ions with ascorbic acid. Copper nanoparticles were quickly formed in less than 10 minutes and were well distributed on the paper fiber surfaces. Paper sheets were characterized by x-ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, and atomic absorption spectroscopy. Antibacterial activity of the CuNP sheets was assessed for by passing Escherichia coli bacteria suspensions through the papers. The effluent was analyzed for viable bacteria and copper release. The CuNP papers with higher copper content showed a high bacteria reduction of log 8.8 for E. coli. The paper sheets containing copper nanoparticles were effective in inactivating the test bacteria as they passed through the paper. The copper levels released in the effluent water were below the recommended limit for copper in drinking water (1 ppm).

The water demand for human activities is rapidly increasing in developing countries. Under these circumstances, preserving aquatic ecosystems should be a priority which requires the development of quality criteria. In this study we perform a preliminary prioritization of the risky substances based on reported ecotoxicological studies and guidelines for the Biobio watershed (Central Chile). Our specific aims are (1) reviewing the scientific information on the aquatic pollution of this watershed, (2) determining the presence and concentration of potential toxic substances in water, sediment and effluents, (3) searching for quality criteria developed by other countries for the selected substances and (4) prioritizing the most risky substances by means of deterministic ecotoxicological risk assessment. We found that paper and mill industries were the main sources of point pollution, while forestry and agriculture were mostly responsible for non-point pollution. The most risky organic substances in the water column were pentachlorophenol and heptachlor, while the most relevant inorganic ones were aluminum, copper, unionized ammonia and mercury. The most risky organic and inorganic substances in the sediment were phenanthrene and mercury, respectively. Our review highlights that an important effort has been done to monitor pollution in the Biobio watershed. However there are emerging pollutants and banned compounds—especially in sediments—that require to be monitored. We suggest that site-specific water quality criteria and sediment quality criteria should be developed for the Biobio watershed, considering the toxicity of mixtures of chemicals to endemic species, and the high natural background level of aluminum in the Biobio.

Groundwater resources are important sources of drinking water in Africa, and they are hugely important in sustaining urban livelihoods and supporting a diverse range of commercial and agricultural activities. Groundwater has an important role in improving health in sub-Saharan Africa (SSA). An estimated 250 million people (40% of the total) live in urban centres across SSA. SSA has experienced a rapid expansion in urban populations since the 1950s, with increased population densities as well as expanding geographical coverage. Estimates suggest that the urban population in SSA will double between 2000 and 2030. The quality status of shallow urban groundwater resources is often very poor due to inadequate waste management and source protection, and poses a significant health risk to users, while deeper borehole sources often provide an important source of good quality drinking water. Given the growth in future demand from this finite resource, as well as potential changes in future climate in this region, a detailed understanding of both water quantity and quality is required to use this resource sustainably. This paper provides a comprehensive assessment of the water quality status, both microbial and chemical, of urban groundwater in SSA across a range of hydrogeological terrains and different groundwater point types. Lower storage basement terrains, which underlie a significant proportion of urban centres in SSA, are particularly vulnerable to contamination. The relationship between mean nitrate concentration and intrinsic aquifer pollution risk is assessed for urban centres across SSA. Current knowledge gaps are identified and future research needs highlighted.Les ressources en eaux souterraines sont des sources importantes d’eau potable en Afrique, et elles sont d’une énorme importance pour les êtres vivants en milieu urbain et pour le soutien d’une gamme diversifiée d’activités commerciales et agricoles. Les eaux souterraines jouent un rôle important en améliorant la santé en Afrique sub-saharienne (ASS). 250 millions de personnes environ (40% du total) vivent dans des centres urbains à travers l’ASS. L’ASS a connu une expansion rapide de ses populations urbaines depuis les années 1950, avec une augmentation à la fois des densités de population et de leur extension géographique. Les estimations prévoient un doublement de la population urbaine de l’ASS entre 2000 et 2030. L’état qualitatif des ressources en eau souterraine urbaines peu profondes est souvent très pauvre du fait de l’insuffisance de la gestion des déchets et de la protection de la ressource, et pose un risque sanitaire significatif pour les utilisateurs, alors que des ressources plus profondes captées par forage fournissent souvent une source importante d’eau potable de bonne qualité. Etant donné la croissance de la demande future de cette ressource limitée, ainsi que le changement climatique potentiel dans cette région dans le futur, une compréhension détaillée de la quantité et la qualité de cette ressource est exigée pour son utilisation durable. Cet article fournit une évaluation complète de l’état qualitatif, à la fois microbien et chimique, des eaux souterraines urbaines en ASS à travers une gamme de contextes hydrogéologiques et de différents types de point d’eaux souterraines. Les terrains du sous-sol de faible emmagasinement, qui sont situés sous une proportion significative de centres urbains en ASS, sont particulièrement vulnérables à la contamination. Le rapport entre la concentration moyenne en nitrate et le risque intrinsèque de pollution des aquifères est évalué pour les centres urbains de l’ASS. Des lacunes actuelles en matière de connaissances sont identifiées et les besoins de recherches futurs sont mis en évidence.Los recursos hídricos subterráneos son una fuente importante de agua potable en África y son sumamente importantes para mantener los medios de subsistencia urbanos y para apoyar una amplia gama de actividades comerciales y agrícolas. El agua subterránea tiene un papel importante en la mejora de la salud en el África Subsahariana (SSA). Se calcula que 250 millones de personas (40% del total) viven en centros urbanos en el África Subsahariana. El SSA ha experimentado una rápida expansión en las poblaciones urbanas desde la década de 1950, con el aumento de la densidad de población, así como la ampliación de la cobertura geográfica. Las estimaciones sugieren que la población urbana en África Subsahariana se duplicará entre 2000 y 2030. El estado de calidad del agua subterránea somera es a menudo muy pobre debido a la gestión inadecuada de los desechos y de la protección de las fuentes, representando un riesgo significativo para los usuarios, mientras que los pozos más profundos proporcionan una fuente importante de agua potable de buena calidad. Dado el crecimiento de la demanda futura de este recurso finito, así como los cambios potenciales en el clima futuro en esta región, una comprensión detallada de su cantidad y calidad es necesaria para utilizar este recurso de manera sostenible. Este artículo ofrece una evaluación integral del estado de la calidad del agua, tanto microbiana como química, del agua subterránea urbana en el SSA a lo largo de una serie de terrenos hidrogeológicos y diferentes tipos de puntos de agua subterránea. Los basamentos de bajo almacenamiento, que subyacen a una proporción significativa de los centros urbanos del África Subsahariana, son particularmente vulnerables a la contaminación. Se evalúa la relación entre la concentración media de nitratos y el riesgo intrínseco de contaminación acuífera para los centros urbanos a través de la SSA. Se identifican las deficiencias actuales de conocimientos y se destacan las necesidades de futuras investigaciones.地下水资源是非洲重要的饮用水源,在维系城市生计和支撑各种商业和农业活动中至关重要。地下水在改善撒哈拉以南非洲民众健康方面发挥着重要作用。在撒哈拉以南非洲,预计有2.5亿人居住在城市地区(占总数的40 %)。自从上世纪50年代,本区域城市人口快速膨胀,密度不断增加,面积不断扩大。估测结果显示,撒哈拉以南非洲的城市人口在2000年至2030年间将翻一番。由于废物管理不当及水源污染,城市浅层地下水源水质常常非常差,对用水者产生很大的健康风险,而较深钻井水源常常提供重要的高质量饮水水源。考虑到此有限水源的基础上将来需求的增长以及本地区将来的气候潜在变化,需要详细了解水量和水质状况,以便可持续利用水源。本文从微生物和化学上综合评价了撒哈拉以南非洲各种水质状况地形及不同地下水水点类型的水质状况。在撒哈拉以南非洲,水存储量低的基岩地形在城市中心占有很大的比例,特别容易受到污染。对整个撒哈拉以南非洲的城市中心平均硝酸盐含量和固有的含水层污染风险之间的关系进行了评价。明确了目前的认识空白,并强调了将来的研究需求。.As águas subterrâneas são fontes importantes de água para consumo na África, e são amplamente importantes para sustentar o modo de vida urbano e dar suporte a uma amplitude diversa de atividades comerciais e agrícolas. As águas subterrâneas têm um papel importante no desenvolvimento da saúde na África subsaariana (ASS). São estimadas 250 milhões de pessoas (40% do total) vivendo nos centros urbanos na ASS. ASS tem vivenciado uma rápida expansão na população urbana desde os anos 50, com aumento das densidades populacionais assim como expansão da cobertura geográfica. As estimativas sugerem que a população urbana na ASS dobrará entre 2000 e 2030. As condições de qualidade dos aquíferos livres em áreas urbanas estão frequentemente muito pobres por causa do gerenciamento de perdas e proteção das fontes inadequados, e apresenta um risco significativo à saúde dos usuários, enquanto poços mais profundos frequentemente fornecem fontes importantes de água potável de boa qualidade. Dado o crescimento na demanda futura desse recurso finito, assim como mudanças potenciais no clima futuro da região, um entendimento detalhado da sua quantidade e qualidade é necessário para o uso sustentável deste recurso. Esse estudo fornece uma avaliação compreensiva das condições de qualidade da água, tanto microbiológica quanto química, das águas subterrâneas urbanas na ASS por uma gama de terrenos hidrogeológicos e diferentes tipos pontuais de águas subterrâneas. Terrenos de menor armazenamento de base, que fundamentam uma porção significante dos centros urbanos da ASS, são particularmente vulneráveis a contaminação. A relação entre a concentração média de nitrato e o risco intrínseco de poluição do aquífero é avaliado para os centros urbanos na ASS. Lacunas do conhecimento atual foram identificadas e destaca-se a necessidade de pesquisas futuras.

The connections between forest products operations and water resources in the United States is considered and, where possible, quantified. Manufacture of wood, pulp, and paper products and the influences of forest management and forest products manufacture on water quality are discussed. Most fresh water in the US originates in forested areas. Responsible harvesting strategies, best management practices, and forest re-growth combine to minimize or eliminate changes in water availability and degradation of water quality due to harvesting. Relative to alternative land uses and large-scale disturbance events, forested areas produce the highest quality of fresh water. Water inputs for the manufacture of forest products total about 5.8 billion m3 per year, an amount equal about 0.4% of the surface and groundwater yield from timberland. Approximately 88% of water used in manufacturing is treated and returned directly to surface waters, about 11% is converted to water vapor and released during the manufacturing process, and 1% is imparted to products or solid residuals. Extensive study and continued monitoring of treated effluents suggest few or no concerns regarding the compatibility of current effluents with healthy aquatic systems.

Agro-based pulp and paper mills in India are one of the most polluting industries; in addition, they are high consumers of raw water. Growing scarcity of high quality freshwater as well as stringent regulatory standards is compelling these units to explore appropriate water management options. Based on data obtained through a questionnaire survey and plant visits, this work provides an overview of the water use and effluent treatment status in Indian agro-residue and recycled pulp and paper mills. The challenges faced by this sector are reviewed and practices adopted by progressive units to minimize freshwater use are illustrated through case studies.

Paper mill effluents may contain polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) that are normally generated due to chlorinated bleaching of pulp and paper. We used the semipermeable membrane device (SPMD) to monitor PCDD/F levels upstream and downstream of a paper mill on the Androscoggin River, in Jay (ME). Following the 36 day deployment, SPMD dialysis and cleanup, the samples were analyzed by HRGC/HRMS. Total concentrations of PCDD/Fs in SPMDs (sum of all tetra-through octachlorinated congeners) ranged from 4.71 pg g(-1) to 26.26 pg g(-1). Five out of the targeted 17 toxic congeners were detected, including: 2,3,7,8-TCDF; 1,2,3,7,8-PeCDF; 2,3,4,7,8-PeCDF; 1,2,3,4,6,7,8-HpCDD and OCDD. Permeability reference compounds (PRCs) were used for in situ calibration of the SPMD sampling rate (Rs). In all sites, water concentrations were the highest for OCDD (0.081-0.103 pg l(-1)), and the lowest for 1,2,3,7,8-PeCDF (0.005-0.009 pg l(-1)). There was not a consistent pattern of upstream-downstream gradient in the PCDD/F levels. This suggested that processes other than the mill in Jay (multiple sources, river dynamics) governed the flux of PCDD/Fs in the sampling locations. The SPMD results were validated by comparison to other studies on the Androscoggin River and elsewhere, confirming the potential of the device as a useful monitoring technique for PCDD/Fs in large river systems.

India has a large number of paper manufacturing units, with mills varying in size of operations and type of product, scattered all over the length and breadth of the country. Present study deals with the survey of four different pulp and paper mills (Mill A, Mill B, Mill C and Mill D) in India, differing in their scale of operation as well as raw material usage. Physico-chemical characterization of wastewaters produced by different processing units like digestor house liquors, bleaching section, paper machine backwaters, combined inlet to the ETP and outlet to ETP, for all the four mills, was conducted. Different parameters like pH, Color, COD, BOD, percent Na, SAR, TDS and Total hardness were analyzed and compared. Highly significant differences were thus found between all the processing units of all four mills with p values < 0.01. This evaluation showed that though these mills have effluent treatment facilities installed in their premises, improvements are still needed to increase their efficiencies for treating the discharged wastewaters.

This synthesis report details the process, outputs and intermediate outcomes of the World Bank’s Water and Sanitation Program (WSP) Technical Assistance (TA) to Support Government of India for implementation of the National Urban Sanitation Policy (P131963). The objective of this TA was to (i) strengthen urban sanitation services and target the urban poor by development of strategies for regulation, funds allocation, improved accountability mechanisms and implementation of inclusive sanitation policies at national level and in at least five states, with two of these low-income states (LIS). This was to be supplemented with (ii) enabling design and use of improved performance monitoring systems by Government of India, 3 states and 300 urban local bodies by 2015, and (iii) strengthen capacity of local urban government institutions to provide improved – inclusive and sustainable – sanitation services for all. This TA provides the building blocks for sustainable sanitation improvements which are being adopted and implemented as part of another TA (P131967) in Madhya Pradesh and Tripura to pilot and operationalize City Sanitation Plans (CSPs) towards outcome oriented sector improvements. The areas addressed in this TA include the following specific goals of the NUSP: open defecation free cities, and integrated city-wide sanitation. The TA provided assistance to central government and the states in putting in place various elements identified as necessary for sector improvement, including planning, provisioning and monitoring processes. The TA also identified the need for the cities to see opportunities for financial recovery of investments through reuse and recycle strategies, to strengthen the incentive for investment in sanitation improvements.

As receiving water quality models are being used to address dissolved oxygen issues requiring an increased degree of resolution, a more refined characterization of effluent CBOD can become an important aspect of the analysis. The selection and use of kinetic models to identify effluent specific parameters can have a significant impact on this characterization. This study modeled effluents from six pulp and paper facilities in order to reassess the kinetic models, the data, and experimental design used for a typical effluent characterization. The dual first order model fit these effluents with significantly less error than the traditional first order model suggesting a significant fraction of the CBOD is slowly degradable. Because the dual first order model produces a more refined characterization of CBOD kinetics than the first order model, it places an increased demand upon the data used to inform the parameter estimates. Therefore, analysis of the precision of the parameter estimates and methods for improving estimation precision via experimental design are also discussed.

A further closure of the water circuit in paper mills with a relative high optimization of their water network is limited by the increase of contamination in the water and runnability problems of the paper machine. Therefore, new strategies for saving water must be focussed on the treatment of final effluents of the paper mill, aiming to obtain high quality water that may replace fresh water use in some applications. An appropriate treatment train performed at pilot scale, consisting on a previous clarification stage followed by anaerobic and aerobic treatments, ultrafiltration, and reverse osmosis, made possible producing the highest water quality from the final effluent of the mill. Anaerobic pre-treatment showed very good performance assisting the aerobic stage on removing organics and sulphates, besides it produced enough biogas for being considered as cost-effective. Permeate recovery depended on the silica content of the paper mill effluent, and it was limited to a 50–60%. The reject of the membranes fully met the legislation requirements imposed to effluents arriving to municipal wastewater treatment plants.