Sustainability scholars increasingly recognise that environmental and security challenges that societies face today cannot be understood in isolation from one another. The rising popularity of a nexus approach to water–energy–food–environmental security analysis reflects this trend. Yet, little is known about exactly how previously disconnected scholarship on water security, energy security, food security and environmental security have converged in this way—and how this convergence can become more holistic and analytically meaningful. This paper outlines major conceptual turns within the literature on these four concepts and reflects on the use of nexus analysis in sustainability science as well as ways forward from where we currently stand. A salient finding is that while a nexus approach suggests more integrated analyses, there is still a tendency for siloed approaches focussed on how, for example, water security connects to energy and food security rather than truly integrated approaches.

Background: Perchlorate-induced natrium-iodide symporter (NIS) interference is a well-recognized thyroid disrupting mechanism. It is unclear, however, whether a chronic low-dose exposure to perchlorate delivered by food and drinks may cause thyroid dysfunction in the long term. Thus, the aim of this review was to overview and summarize literature results in order to clarify this issue. Methods: Authors searched PubMed/MEDLINE, Scopus, Web of Science, institutional websites and Google until April 2020 for relevant information about the fundamental mechanism of the thyroid NIS interference induced by orally consumed perchlorate compounds and its clinical consequences. Results: Food and drinking water should be considered relevant sources of perchlorate. Despite some controversies, cross-sectional studies demonstrated that perchlorate exposure affects thyroid hormone synthesis in infants, adolescents and adults, particularly in the case of underlying thyroid diseases and iodine insufficiency. An exaggerated exposure to perchlorate during pregnancy leads to a worse neurocognitive and behavioral development outcome in infants, regardless of maternal thyroid hormone levels. Discussion and conclusion: The effects of a chronic low-dose perchlorate exposure on thyroid homeostasis remain still unclear, leading to concerns especially for highly sensitive patients. Specific studies are needed to clarify this issue, aiming to better define strategies of detection and prevention.

Water is a basic resource for food and fuelwood production. In general, people in rural areas of India consume carbohydrate rich staples with small amounts of animal foods. They mostly depend upon fuelwood for cooking. This study assesses the WFs for food and fuel consumption in rural India. The research question is: What is the green, blue and grey water footprint (WF) of food and cooking fuel consumption per province in rural India (m³/cap/year). It used the WF method for the quantification. Data on food and fuelwood consumption were derived from the National Sample Survey (2011–12). Foods were categorized into 6 groups: 1. Rice; 2. Wheat; 3. Oils and fats; 4. Milk; 5. Other animal foods; and 6. Others. Cooking fuel includes: 1. Fuelwood; 2. Kerosene and 3. LPG. Data related to WFs of food were derived from literature reviews and in case of fuelwood, the WFs were calculated for all the provinces of India. Finally, the total WF of per capita consumption is calculated by adding the WF of food and fuelwood. The result shows that there is a large variation in the green, blue and grey WFs for food consumption across the provinces of India. The average WF for food consumption is about 800 m³/cap/year and for fuelwood is 1630 m³/cap/year. Rice and wheat dominate the green, blue and grey WFs for food, with variations among the provinces. The green WF of rice is larger than the green WF of wheat, while wheat has a larger blue WF. For cooking fuel, the average WF of fuelwood is much larger than the WF of fossil based cooking fuels. The total WF for fuelwood is twice the WF for food, showing that in rural areas of developing countries, fuelwood is water intensive with large impact on freshwater resources. Future prospects of increasing consumption of animal products will increase WFs. However, if also cooking fuel is considered, switching to fossil cooking fuel lowers WFs far more and compensates the increase due to larger animal food consumption. The trends for cooking fuel found in India might also be relevant for other developing countries.

Freshwater use for food production is projected to increase substantially in the coming decades with population growth, changing demographics, and shifting diets. Ensuring joint food-water security has prompted efforts to quantify freshwater use for different food products and production methods. However, few analyses quantify freshwater use for seafood production, and those that do use inconsistent water accounting. This inhibits water use comparisons among seafood products or between seafood and agricultural/livestock products. This 'seafood gap' in the food-water nexus literature will become increasingly problematic as seafood consumption is growing globally and aquaculture is one of the fastest growing animal food sectors in the world. Therefore, the present study 1) reviews freshwater use concepts as they relate to seafood production; 2) provides three case studies to highlight the particular water use concerns for aquaculture, and; 3) outlines future directions to integrate seafood into the broader food-water nexus discussion. By revisiting water use concepts through a focus on seafood production systems, we highlight the key water use processes that should be considered for seafood production and offer a fresh perspective on the analysis of freshwater use in food systems more broadly | Jessica A. Gephart et al., 'The `seafood gap' in the food-water nexus literature?issues surrounding freshwater use in seafood production chains', Advances in Water Resources, vol. 110, pp.505-514, Elsevier BV, 2018

The interactive dynamics in the food, water, and energy system as a nexus (FWEN) are critical to the sustainable development of global cities, and they can be mediated by green and blue infrastructure (GBI) in the urban area. Here we provide a comprehensive literature review to examine how GBI affects FWEN in urban centers, an area which is currently understudied. In order to do this, we undertake a systematic review of the literature using a meta-analytic approach and topic modelling. Based on our synthesis, we develop a conceptual framework of the key links between urban GBI and FWEN and the direction and magnitude of the relationship. We found that GBIs can benefit food supply, energy saving, and climate change mitigation but at a price of food safety and water contamination. Well-designed urban construction can help curb the negative effects. Therefore, we need to make deliberate and integrative policy to link GBI with each element in urban FWEN. Moreover, the focus of studies on GBIFWEN links is also heterogeneous across cities: urban agriculture and food security are priorities in cities located in Africa and Asia as well as in lower income and larger cities (but not metropolitan areas), while the cooling effect of green space has been a focus for cities of middle or high income. Finally, current research focuses on isolated analysis, lacking integrated studies needed for decision making supporting tools. While isolated analyses lead to connectivity failures and can result in adverse impacts, integrated analyses can identify interdependencies of environmental resources between parts of a cycle and across different scales, which can increase resource efficiency and minimize environmental degradation. Therefore, our key findings point out the importance of linking the effects of GBI on each component of FWEN in both research and policy making.

A novel and green method was developed for enrichment of maneb (manganese ethylene-bisdithiocarbamate) with a supramolecular solvent liquid phase microextraction method. The microextraction method has been used for the first time in the literature for separation-preconcentration of maneb. 1-decanol and tetrahydrofuran were used in the supramolecular solvent formation. The Mn²⁺ content of maneb was extracted in the supramolecular solvent phase as 1-(2-pyridylazo)-2-naphthol complex at pH 12.0. Manganese concentration was determined by UV–Vis spectrophotometer at 555 nm. Then, the maneb concentration equivalent to manganese concentration was calculated. The analytical parameters which effective in the method, including pH, volume of reagents, and sample volume were optimized. The limit of detection and the limit of quantification values for maneb were calculated as 2.22 μg L⁻¹ and 7.32 μg L⁻¹, respectively. The method was successfully applied in the analysis of the maneb content of water and food samples.

Sanjiv de Silva, 'Structural vulnerability to climate change in Bangladesh: a literature review. (Project report prepared by IWMI for the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) under the project "Water-related Interventions to Reduce Vulnerability to Climate Change: Do they Address the Structural Causes of Gendered Vulnerability in the IGP (Indo Gangetic Plains)")', International Water Management Institute (IWMI), 2014