This document is the first systematic discussion of the most important lessons of the APPJ Project of the European Union, which was implemented between the years 1993 and 2001. The project was prepared to respond to the emergency health situation of the cholera epidemic of 1991. The proposed project was to comment on building autonomous systems of drinking water in peri-urban areas not served by the SEDAPAL drinking water network. Lessons learned include: 1) It is not enough to build drinking water systems; 2) It is essential to ensure the existence of units that manage the system efficiently. 3) It is important to operate a monitoring program of the autonomous systems in Lima. This document has been divided into five chapters and three annexes. The first chapter presents the background of the project, the features of the proposal and phases their execution. The second deals with processes that led to major improvements in the construction of the autonomous systems of drinking water. The third chapter discusses the various aspects and factors influencing the sustainability of water systems. The fourth chapter discusses the role of institutional actors involved directly or indirectly in the sustainability of building water systems. Finally, the fifth chapter presents conclusions and lessons. The document ends with three annexes: the first is information on costs and volume of sales of systems visited; the second is a summary of the information status of systems visited, and the third is a list of NGOs who have participated in the implementation of the project.

This document is the first systematic discussion of the most important lessons of the APPJ Project of the European Union, which was implemented between the years 1993 and 2001. The project was prepared to respond to the emergency health situation of the cholera epidemic of 1991. The proposed project was to comment on building autonomous systems of drinking water in peri-urban areas not served by the SEDAPAL drinking water network. Lessons learned include: 1) It is not enough to build drinking water systems; 2) It is essential to ensure the existence of units that manage the system efficiently. 3) It is important to operate a monitoring program of the autonomous systems in Lima. This document has been divided into five chapters and three annexes. The first chapter presents the background of the project, the features of the proposal and phases their execution. The second deals with processes that led to major improvements in the construction of the autonomous systems of drinking water. The third chapter discusses the various aspects and factors influencing the sustainability of water systems. The fourth chapter discusses the role of institutional actors involved directly or indirectly in the sustainability of building water systems. Finally, the fifth chapter presents conclusions and lessons. The document ends with three annexes: the first is information on costs and volume of sales of systems visited; the second is a summary of the information status of systems visited, and the third is a list of NGOs who have participated in the implementation of the project.

In the present study, a new ultrasound assisted extraction (UAE) method was developed for preconcentration of selenite, Se(iv), from sample matrices prior to analysis. The method is based on complex formation between phenoxazine dye, resazurin, and triiodide, I₃⁻, which is produced by oxidation of iodide with Se(iv) in the presence of cetylpyridinium chloride (CPC) at pH 5.0, and then the extraction of the complex into the micellar phase of the extracting agent. The proposed process offers good sensitivity, ease of use and short analysis time. The variables affecting complex formation and extraction efficiency were studied and optimized in detail. Under optimal conditions, a good linear relationship was obtained in the range of 2.5–120 μg L⁻¹ with a detection limit of 0.76 μg L⁻¹. The precision was found to be 3.5% (n: 5, 10 and 40 μg L⁻¹). After preconcentration of a 15 mL sample, a sensitivity enhancement factor of 34.1 was obtained. The method offers good sensitivity, ease of use and short analysis time. Total inorganic Se was determined after the reduction of Se(vi) to Se(iv) using hydrochloric acid. The validation was evaluated by analysis of two standard reference materials (SRMs) and the recovery test. Finally, the method was successfully applied to the determination of inorganic Se in selected samples, and recoveries higher than 93.7% to 103% were obtained.

OBJECTIVES: To carrying out an integrated analysis on regional environment and human health in China and to detect the association between longevity and daily element intake from food and drinking water. DESIGN: Cross-sectional study. SETTING: All the 18 cities and counties in Hainan Province. MEASUREMENTS: The distribution of elderly population and longevity indexes at a county level in Hainan Province were investigated. Quality of food and drinking water in Hainan was evaluated by comparing the chemical elements with National Standards. In addition, the association between element concentrations in food and water and longevity was examined using spearman’s rank correlation. RESULTS: The proportion of elderly people is higher in the northern part of the province compared with southern counties. Food contributes a greater proportion of daily element intake than drinking water. Compared with the National Standards, reaching rates for elements were over 85% for both food and drinking water. There was a positive correlation between daily intake of Cu, Se, and Zn from food and water and aging and longevity indexes, and a negative correlation between Pb intake and these indexes. CONCLUSION: The quality of food and water in Hainan Province are good and that, compared with water, food is a more important source of trace elements. An appropriate supply of Cu, Se, and Zn is important, whereas excessive intake of Pb should be avoided. The findings also provide basic data to support further studies on regional variations in longevity and their relationship to diet and drinking water.

Selenium is a trace element essential for the proper functioning of human body. Since it can only be obtained through our diet, knowing its concentrations in different food products is of particular importance. The measurement of selenium content in complex food matrices has traditionally been a challenge due to the very low concentrations involved. Some of the difficulties may arise from the abundance of various compounds, which are additionally present in examined material at different concentration levels. The solution to this problem is the efficient separation/preconcentration of selenium from the analyzed matrix, followed by its reliable quantification. This review offers an insight into cloud point extraction, a separation technique that is often used in conjunction with spectrometric analysis. The method allows for collecting information on selenium levels in waters of different complexity (drinking water, river and lake waters), beverages (wine, juices), and a broad range of food (cereals, legumes, fresh fruits and vegetables, tea, mushrooms, nuts, etc.).

Determination of selenium compounds in air, soil, water, and food samples is of interest as selenium's bioavailability and toxicity depend on its concentration level. Among analytical approaches, electrochemical sensors are more favorable due to their simplicity, time-saving, cost-effectiveness, and high sensitivity. In this study, we report electrochemical determination and analysis of selenium at the surface of a pencil graphite electrode modified with a sensing composite film composed of acetophenone (2,4-dinitrophenyl)hydrazone, polypyrrole, and copper nanoparticles. To produce durable films, cyclic voltammetry technique, as a facile modification procedure, was used. The electrochemical response of the fabricated modified electrode to selenium was evaluated using cyclic and square wave voltammetry techniques. The modified electrode presented excellent electrocatalytic ability with favorable electrochemical parameters (α = 0.24, log kₛ = 3.27 s⁻¹, and Γ = 3.74 × 10⁻⁷ mmol cm⁻²) for the reduction of selenium in acidic media with optimized pH of 2 and working potential of around −0.85 V (vs. SCE). The scanning electron microscopy images of the modified surfaces proved the formation of aggregates in nanoscale, indicating successful electrodeposition and electro-polymerization processes to modify the pencil graphite surface. This revealed a linear electrochemical response to selenium within the concentration range from 50 nM to 110 nM with the limit of detection (LOD) of 16.58 nM. The analytical application of the new sensor was also examined with respect to its applicability in food samples, such as milk, and water samples, including food wastewater samples, suggesting valid determination of selenium without any side interference.

A green vortex assisted based liquid-liquid microextraction (VA-LLME) method was developed for preconcentration of selenium. Ammonium pyrrolidine dithiocarbamate (APDC) was used to form a hydrophobic complex with selenium in natural water, agricultural soil and food samples by GFAAS. Whereas Triton X-114, a nonionic surfactant and 1-butyl-3-methylimidazolium hexafluorophosphate ionic liquid were used for Se extraction as a dispersing medium. The conical flasks contents were shack on a vortex mixer to increase the extraction efficiency. Multivariate techniques were used to evaluate extraction parameters; pH, vortex time, APDC amount, volume of ionic liquid and Triton X-114 and centrifugation rate on the recovery of Se. The central composite design (CCD) was used for further optimization of the essential extraction parameters. The enhancement factor and limit of detection were obtained as 98.7 and 0.07 µg L⁻¹. The certified reference materials was used for accuracy of method and the related standard deviation was found to be 3.51%. The resulted data indicated that concentrations of Se in all types of water samples were below the permissible limit recommended by WHO.

Although fish is widely consumed by humans for its nutritional properties, accumulation of heavy metals can pose serious health hazards. Widespread common carp Cyprinus carpio is cultured worldwide and represents an economically important species for fisheries in several countries. These include Turkey, where C. carpio often makes for a large part of the sales of the locally marketed fish and also for a traditional dish. This study provides a review of bioaccumulation of metals in tissues of C. carpio from water bodies of Anatolia and also includes reference to worldwide studies. From 42 water bodies across the region, 27 metals in total were studied, of which Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were the most widely analysed, mainly in the muscle, liver and gill tissues. Amongst the potentially toxic metals, Cd, Cr and Pb occurred in several water bodies at concentrations not only above maximum allowed limits but also higher relative to other water bodies worldwide, even though As, Hg and Ni were also sometimes present at potentially hazardous concentrations. The essential metals Cu, Fe, Mn, Se and Zn were detected at various concentrations, with the latter two occasionally above limit. All water bodies flagged as having especially critical (i.e. above limit) concentrations of toxic metals supported C. carpio fisheries from highly populated regions, raising concern about food safety and calling for preventative measures. Given the significantly lower bioaccumulation levels in the muscle relative to the liver and gill tissues, it is suggested that consumption of C. carpio as fillets may be safer than after processing into e.g. meat balls and sausages. The limits of 1.0 μg/g for Cr and 1.15 μg/g for Se, currently lacking from the Turkish food safety legislation, are proposed, and it is suggested that a similar meta-analytical approach as adopted in this study may benefit other countries where C. carpio represents an important fisheries resource.

A newly synthesized polystyrene-g-polyoleic acid-g-polyethylene glycol graft copolymer (PoleS-PEG) was used as adsorbent in the solid phase microextraction of selenium ions by using electrothermal atomic absorption spectrometry (ETAAS). Neodymium magnet was used for separation of analyte ions. Various analytical parameters such as pH, adsorbent amount, mixing time, eluent solution, sample volume, etc. were optimized. The matrix effects of some cations and anions were also studied. The capacity of the adsorbent was found 11.5 mg g−1. The preconcentration factor was found to be 50. The detection limit (LOD) and quantification limit (LOQ) were found 6.06 ng L−1 and 20 ng L−1, respectively. The calibration curve was linear in the range of 0.02–4.0 μg L−1. Relative standard deviation was found 3.2%. The accuracy of the method was provided by using standard reference materials. The optimized method was successfully applied to natural water and food samples.

In the current study, we have developed a green water switchable liquid–liquid microextraction method for separation, preconcentration, and estimation of selenium concentration in the real samples. First time introducing the water switchable liquid–liquid microextraction method to determine the trace level selenium in different food and soft drink samples. Water switchable medium was formed by the reaction of diethylenetriamine base when exposed to uniformed pressure of carbon dioxide. After being exposed to carbon dioxide, water switchable medium reversibly exchanges in two separated aqueous and organic phases. Advantages of carbon dioxide uses are cheap, environmental friendly, non-accumulation, removable, and require the opaque materials for operating container. Water switchable phenomena occurred easily from low polarity to high polarity organic solvent. Experimental variables of the water switchable liquid–liquid microextraction (LLME) method were optimized into its optimum values such as pressure, pH, centrifugation speed, extraction time, and concentration of complexing agent. The certified reference material of Canada Lake Water (TMDA-53.3) and CS-M-3 Mushroom (Boletus edulis) was used for validation of the present water switchable LLME method. Enhancement factor and limit of detection were obtained 85.5 and 0.018 μg kg⁻¹, respectively. Developed green water switchable LLME method was successfully applied for assessment of total selenium in tomato, pumpkin seed, mushroom, garlic, rice, pistachio, chickpea, hazelnut, walnut, apple juice, and ice tea samples.