The increasing demand for water, energy and food, and the interdependence of these systems could lead to potential human conflict in the future. This was seen in the food crisis of 2008, which stirred a renewed interest in taking a "systems" approach to managing resources. The initial flurry of activities led to many nexus frameworks, but there remains a gap between theory and its implementation. This paper tries to look at various frameworks and unpacks the concept of nexus in order to develop matrices to help quantify and understand the interlinkages between the nexus systems. It suggests multi-level and multi-system indices to measure the health of nexus systems and to identify the weak links. It is hoped that such frameworks can be used at country level, and eventually be used to measure and rank countries on the health of their systems. The paper suggests a questionnaire that can be used (after modifying for local conditions) to collect country-level institutional and political-economy data (which is difficult to get from online resources) to be used in the framework | A. Sood, A. Nicol, I. Arulingam, 'Unpacking the water-energy-environment-food nexus: working across systems', pp.43p, International Water Management Institute (IWMI), 2019

Reclaimed water has been identified as a viable and cost-effective solution to water shortages impacting agricultural production. However, lack of consumer acceptance for foods irrigated with reclaimed and treated water remains one of the greatest hurdles for widespread farm-level adoption. Using survey data from 760 participants in the mid-Atlantic region of the U.S., this paper examines consumer preferences for six sources of reclaimed irrigation water and identifies statistically significant relationships between consumers’ demographic characteristics and their preferences for each type of reclaimed water. Key findings suggest that adult consumers prefer rain water to all other sources of reclaimed water. Women are less likely than men to prefer reclaimed irrigation water sources and are particularly concerned about the use of black and brackish water. Consumers who had heard about reclaimed water before are more likely to accept its use. Drawing on evidence from survey and experimental research, this paper also identifies disgust, neophobia and safety concerns as the key issues that lead consumers to accept or reject foods produced with reclaimed water. Finally, we identify avenues for future research into public acceptance of reclaimed water based on our analysis and evidence from prior research.

Colin J. Chartres, 'Will improving the productivity of "green" water lead to food security?', 2014

To explore the perceptions of food access by African American women in Flint, MI.Using womanist theory, in which African American women's experiential knowledge centered the analysis, 8 focus groups were conducted during fall/spring, 2014–2015. Seventeen mothers aged 21–50 years with children aged <18 years and 13 women aged >60 years comprised the groups.The high cost of water, poor availability of healthy foods in inner-city stores, and limited transportation were barriers to accessing healthy food. Conversely, receiving food from food giveaways, friends, and family, as well as access to transportation facilitated food access. These women also reported discriminatory experiences and diet-related health concerns. Participants were keenly aware of available free community resources and gender, racial, and income barriers to accessing them.Understanding these barriers and facilitators provides information to aid local food policy assistance decisions and inform community-based interventions, especially given the lead contamination of water and the purported importance of a healthy diet to sequester lead.

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.

A dispersive liquid–liquid microextraction procedure for lead(II) as its 5-(4-dimethylaminobenzylidene) rhodanine complex has been established prior to its microsampling flame atomic absorption spectrometric determination. The influences of various analytical parameters including pH, solvent type and volume, dispersive solvent type and volume, 5-(4-dimethylaminobenzylidene) rhodanine amount, salt effect, and centrifugation time and speed were investigated. The effects of certain alkali, alkaline earth, and transition metal ions on the quantitative extraction of lead(II) were also studied. Quantitative recoveries were obtained at pH 6. The enrichment factor was calculated as 125. The detection limit for lead is 1.1 μg/L. The accuracy of the method was tested with the additions recovery test and analysis of the standard reference materials (SPS-WW2 waste water, NIST SRM 1515 apple leaves, and TMDA-51.3 fortified water). Applications of the present procedure were tested by analyzing water and food samples.

In this study, ultralayered Co₃O₄ adsorbent was synthesized and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The surface area of the solid material was found to be 75.5m²g⁻¹ by BET method. The ultralayered Co₃O₄ was used for the first time as an effective adsorbent for the preconcentration of the Pb(II) ions in various samples prior to flame atomic absorption detection. Analytical parameters affecting the solid phase extraction of Pb(II) such as pH, adsorption and elution contact time, eluent volume and concentration, sample volume and common matrix ions were investigated. The recovery values for Pb(II) were found to be ≥92% even in the presence of 75,000mgL⁻¹ Na(I), 75,000mgL⁻¹ K(I), and 75,000mgL⁻¹ Ca(II) ions. 10s vortexing time was enough for both adsorption and elution contact times. The elution was easily made with 2mL of 2.0molL⁻¹ HNO₃. The reusability (170 cycles) and adsorption capacity (35.5mgg⁻¹) of ultralayered Co₃O₄ were excellent. The preconcentration factor of the method and detection limit were found to be 175 and 0.72µgL⁻¹, respectively. The described method was validated with certified reference material (RM 8704 Buffalo River Sediment, BCR-482 Licken and SPS-WW1 Batch 111-Wastewater) and spiked real samples. It was also applied for the preconcentration of Pb(II) ions in various water (well water, mineral water, waste water and sea water), food (cauliflower and barley), street sediment and tobacco samples.

A new biosorbent material from eggshell membrane was synthesized through thiol functionalization, which is based on the reduction of disulfide bonds in eggshell membrane by ammonium thioglycolate. The thiol-functionalized eggshell membrane was characterized, and its application as an adsorbent for removal of Cr(VI), Hg(II), Cu(II), Pb(II), Cd(II), and Ag(I) from aqueous water has been investigated. The experimental results revealed that the adsorption abilities of the thiol-functionalized eggshell membrane toward Cr(VI), Hg(II), Cu(II), Pb(II), Cd(II), and Ag(I) improved 1.6-, 5.5-, 7.7-, 12.4-, 12.7-, and 21.1-fold, respectively, compared with that of the eggshell membrane control. The adsorption mechanism and adsorption performance, including the adsorption capacity and the kinetics of the thiol-functionalized eggshell membrane for the target heavy metals, were investigated. The effects of solution pH, coexisting substances, and natural water matrices were studied. The thiol-functionalized eggshell membrane can be used as column packing to fabricate a column for real wastewater purification.