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Update of the risk assessment of nickel in food and drinking water Full text
2020
EFSA Panel on Contaminants in the Food Chain (CONTAM) | Dieter Schrenk | Margherita Bignami | Laurent Bodin | James Kevin Chipman | Jesús del Mazo | Bettina Grasl‐Kraupp | Christer Hogstrand | Laurentius (Ron) Hoogenboom | Jean‐Charles Leblanc | Carlo Stefano Nebbia | Evangelia Ntzani | Annette Petersen | Salomon Sand | Tanja Schwerdtle | Christiane Vleminckx | Heather Wallace | Thierry Guérin | Peter Massanyi | Henk Van Loveren | Katleen Baert | Petra Gergelova | Elsa Nielsen
Update of the risk assessment of nickel in food and drinking water Full text
2020
EFSA Panel on Contaminants in the Food Chain (CONTAM) | Dieter Schrenk | Margherita Bignami | Laurent Bodin | James Kevin Chipman | Jesús del Mazo | Bettina Grasl‐Kraupp | Christer Hogstrand | Laurentius (Ron) Hoogenboom | Jean‐Charles Leblanc | Carlo Stefano Nebbia | Evangelia Ntzani | Annette Petersen | Salomon Sand | Tanja Schwerdtle | Christiane Vleminckx | Heather Wallace | Thierry Guérin | Peter Massanyi | Henk Van Loveren | Katleen Baert | Petra Gergelova | Elsa Nielsen
Abstract The European Commission asked EFSA to update its previous Opinion on nickel in food and drinking water, taking into account new occurrence data, the updated benchmark dose (BMD) Guidance and newly available scientific information. More than 47,000 analytical results on the occurrence of nickel were used for calculating chronic and acute dietary exposure. An increased incidence of post‐implantation loss in rats was identified as the critical effect for the risk characterisation of chronic oral exposure and a BMDL10 of 1.3 mg Ni/kg body weight (bw) per day was selected as the reference point for the establishment of a tolerable daily intake (TDI) of 13 μg/kg bw. Eczematous flare‐up reactions in the skin elicited in nickel‐sensitised humans, a condition known as systemic contact dermatitis, was identified as the critical effect for the risk characterisation of acute oral exposure. A BMDL could not be derived, and therefore, the lowest‐observed‐adverse‐effect‐level of 4.3 μg Ni/kg bw was selected as the reference point. The margin of exposure (MOE) approach was applied and an MOE of 30 or higher was considered as being indicative of a low health concern. The mean lower bound (LB)/upper bound (UB) chronic dietary exposure was below or at the level of the TDI. The 95th percentile LB/UB chronic dietary exposure was below the TDI in adolescents and in all adult age groups, but generally exceeded the TDI in toddlers and in other children, as well as in infants in some surveys. This may raise a health concern in these young age groups. The MOE values for the mean UB acute dietary exposure and for the 95th percentile UB raises a health concern for nickel‐sensitised individuals. The MOE values for an acute scenario regarding consumption of a glass of water on an empty stomach do not raise a health concern.
Show more [+] Less [-]Update of the risk assessment of nickel in food and drinking water Full text
2020
Schrenk, Dieter | Bignami, Margherita | Bodin, Laurent | Chipman, James Kevin | del Mazo, Jesús | Grasl-Kraupp, Bettina | Hogstrand, Christer | Hoogenboom, Laurentius | Leblanc, Jean Charles | Nebbia, Carlo Stefano | Ntzani, Evangelia | Petersen, Annette | Sand, Salomon | Schwerdtle, Tanja | Vleminckx, Christiane | Wallace, Heather | Guérin, Thierry | Massanyi, Peter | Van Loveren, Henk | Baert, Katleen | Gergelova, Petra | Nielsen, Elsa
The European Commission asked EFSA to update its previous Opinion on nickel in food and drinking water, taking into account new occurrence data, the updated benchmark dose (BMD) Guidance and newly available scientific information. More than 47,000 analytical results on the occurrence of nickel were used for calculating chronic and acute dietary exposure. An increased incidence of post-implantation loss in rats was identified as the critical effect for the risk characterisation of chronic oral exposure and a BMDL10 of 1.3 mg Ni/kg body weight (bw) per day was selected as the reference point for the establishment of a tolerable daily intake (TDI) of 13 μg/kg bw. Eczematous flare-up reactions in the skin elicited in nickel-sensitised humans, a condition known as systemic contact dermatitis, was identified as the critical effect for the risk characterisation of acute oral exposure. A BMDL could not be derived, and therefore, the lowest-observed-adverse-effect-level of 4.3 μg Ni/kg bw was selected as the reference point. The margin of exposure (MOE) approach was applied and an MOE of 30 or higher was considered as being indicative of a low health concern. The mean lower bound (LB)/upper bound (UB) chronic dietary exposure was below or at the level of the TDI. The 95th percentile LB/UB chronic dietary exposure was below the TDI in adolescents and in all adult age groups, but generally exceeded the TDI in toddlers and in other children, as well as in infants in some surveys. This may raise a health concern in these young age groups. The MOE values for the mean UB acute dietary exposure and for the 95th percentile UB raises a health concern for nickel-sensitised individuals. The MOE values for an acute scenario regarding consumption of a glass of water on an empty stomach do not raise a health concern.
Show more [+] Less [-]Water–Energy–Food Nexus Framework for Promoting Regional Integration in Central Asia Full text
2020
Olimjon Saidmamatov | Inna Rudenko | Stephan Pfister | Jacek Koziel
Water–Energy–Food Nexus Framework for Promoting Regional Integration in Central Asia Full text
2020
Olimjon Saidmamatov | Inna Rudenko | Stephan Pfister | Jacek Koziel
This paper focuses on regional integration through the lenses of the Water–Food–Energy (WEF) nexus, a concept putting strong emphasis on cross-sectoral and multi-level interactions as well as on resource interdependencies. There is an extensive amount of published research focusing on the Aral Sea basin. In this paper, the authors build upon these different contributions and provide a meta-analysis of the literature of WEF nexus opportunities in Central Asia (CA) countries. This paper contributes to ongoing discussions regarding how the WEF Nexus can represent an opportunity for reinforced collaboration regarding resources management. To do so, focusing on existing literature, this paper first (1) explores how the nexus can be a relevant instrument for regional integration. Second (2), it provides an overview of water, food, energy conditions and challenges in the Aral Sea basin in particular. Third (3), synthesizing existing research, the authors identify critical variables to be considered as hurdles or leverage points for WEF nexus implementation in the Aral Sea basin. Finally (4), we go back to our initial set of questions and identify some possible avenues for future research.
Show more [+] Less [-]Water–Energy–Food Nexus Framework for Promoting Regional Integration in Central Asia Full text
2020
Olimjon Saidmamatov | Inna Rudenko | Stephan Pfister | Jacek Koziel
This paper focuses on regional integration through the lenses of the Water&ndash:Food&ndash:Energy (WEF) nexus, a concept putting strong emphasis on cross-sectoral and multi-level interactions as well as on resource interdependencies. There is an extensive amount of published research focusing on the Aral Sea basin. In this paper, the authors build upon these different contributions and provide a meta-analysis of the literature of WEF nexus opportunities in Central Asia (CA) countries. This paper contributes to ongoing discussions regarding how the WEF Nexus can represent an opportunity for reinforced collaboration regarding resources management. To do so, focusing on existing literature, this paper first (1) explores how the nexus can be a relevant instrument for regional integration. Second (2), it provides an overview of water, food, energy conditions and challenges in the Aral Sea basin in particular. Third (3), synthesizing existing research, the authors identify critical variables to be considered as hurdles or leverage points for WEF nexus implementation in the Aral Sea basin. Finally (4), we go back to our initial set of questions and identify some possible avenues for future research.
Show more [+] Less [-]Sustainable groundwater management in India needs a water-energy-food nexus approach
2020
Mukherji, Aditi
The Role of Communication in Managing Complex Water–Energy–Food Governance Systems Full text
2020
Robert A. Greer | Bryce Hannibal | Kent Portney
The Role of Communication in Managing Complex Water–Energy–Food Governance Systems Full text
2020
Robert A. Greer | Bryce Hannibal | Kent Portney
Managers of federal, state, local, and nonprofit organizations around the world are faced with the complex task of managing interconnected systems of scarce resources. One key example of this has been the recent research on the connections between water, energy, and food/agriculture, and the problem of managing these resources to be sustainable and reduce the likelihood of resource depletion. While engineering research has focused on achieving greater efficiencies in resource management, less attention has been given to issues of governance within the fragmented, decentralized, and polycentric systems that are responsible for resource delivery. The central question animating this paper is whether resource management decisions in water, energy, and food are siloed, and what theoretical frameworks can be leveraged to develop strategies to break down existing silos. Results from a survey of water agencies suggests that there is little communication between the water, energy, and food policy areas. If achieving greater nexus requires increased communication and repeated interactions, there is significant work to be done to re-think how policy and management are organized and conducted.
Show more [+] Less [-]The Role of Communication in Managing Complex Water–Energy–Food Governance Systems Full text
2020
Greer, Robert A. | Hannibal, Bryce | Portney, Kent
Managers of federal, state, local, and nonprofit organizations around the world are faced with the complex task of managing interconnected systems of scarce resources. One key example of this has been the recent research on the connections between water, energy, and food/agriculture, and the problem of managing these resources to be sustainable and reduce the likelihood of resource depletion. While engineering research has focused on achieving greater efficiencies in resource management, less attention has been given to issues of governance within the fragmented, decentralized, and polycentric systems that are responsible for resource delivery. The central question animating this paper is whether resource management decisions in water, energy, and food are siloed, and what theoretical frameworks can be leveraged to develop strategies to break down existing silos. Results from a survey of water agencies suggests that there is little communication between the water, energy, and food policy areas. If achieving greater nexus requires increased communication and repeated interactions, there is significant work to be done to re-think how policy and management are organized and conducted.
Show more [+] Less [-]The Role of Communication in Managing Complex Water–Energy–Food Governance Systems Full text
2020
Robert Greer | Bryce Hannibal | Kent Portney
Managers of federal, state, local, and nonprofit organizations around the world are faced with the complex task of managing interconnected systems of scarce resources. One key example of this has been the recent research on the connections between water, energy, and food/agriculture, and the problem of managing these resources to be sustainable and reduce the likelihood of resource depletion. While engineering research has focused on achieving greater efficiencies in resource management, less attention has been given to issues of governance within the fragmented, decentralized, and polycentric systems that are responsible for resource delivery. The central question animating this paper is whether resource management decisions in water, energy, and food are siloed, and what theoretical frameworks can be leveraged to develop strategies to break down existing silos. Results from a survey of water agencies suggests that there is little communication between the water, energy, and food policy areas. If achieving greater nexus requires increased communication and repeated interactions, there is significant work to be done to re-think how policy and management are organized and conducted.
Show more [+] Less [-]The competitive relationship between food and energy production for water in China Full text
2020
Hua, En | Wang, Xinyu | Engel, Bernard A. | Sun, Shikun | Wang, Yubao
Water, Energy and Food (WEF) are key elements of economic and social sustainable development, and present a complex nexus. Existed WEF nexus research is mainly confined to qualitative analyses, and it needs constant improvement and increases quantitative analyses. In China, water security is the most prominent problem in the WEF-nexus, which is manifested in the competitive relationship between food and energy production for water. Therefore, the matter of alleviating water resources stress has become a difficult and hot issue. After improving the existed water footprint accounting method for food and energy production, this study calculated the food water footprints (blue water footprint and green water footprint) in the 31 provinces of mainland China in 2015, as well as the blue water footprints of major energy systems (coal, oil, natural gas and thermal power generation). This study proposed water resources pressure index (IWS), water resources pressure contribution rate of food and energy (WCR), water consumption rate of food and energy (n) and competition composite index (CCI) of WEF, which were used to evaluate the consumption of water resources in food and energy production in different regions, and assess the intensity of competition for water resources in food and energy production. The results showed that the national food water footprint in 2015 was 690.8 Gm³, and the blue food water footprint was 287.8 Gm³. The main water-consuming blue energy water footprint was 18.5 Gm³, and coal production accounted for 9.9% and thermal power generation accounted for 87.6%. According to the competition indicators, the competition relationship among the administrative regions of the 31 provinces in mainland China was obtained. For example, 5 provinces had serious competition and 19 provinces had weak competition. The water consumption of the energy industry continues to grow rapidly by economic development. Corresponding measures should be taken according to the different competition levels for water resources.
Show more [+] Less [-]Decision-making and integrated assessment models of the water-energy-food nexus Full text
2020
Rising, James
Studying trade-offs in the long-term development of water-energy-food systems requires a new family of hydroeconomic optimization models. This article reviews the central considerations behind these models, highlighting the importance of water infrastructure, the foundations of a theory of decision-making, and the handling of uncertainty. Integrated assessment models (IAMs), used in climate change policy research, provide insights that can support this development. In particular, IAM approaches to intertemporal decision-making and economic valuation can improve existing models. At the same time, IAMs have weaknesses identified elsewhere and can benefit from the development of hydroeconomic models, which have complementary strengths.
Show more [+] Less [-]Economic Efficiency of Food Safety Modernization Act: Preventing Illnesses from Contaminated Water Full text
2020
Bahalou Horeh, Marziyeh | Elbakidze, Levan
Sustainable food system policies need to address environmental pressures and impacts: The example of water use and water stress Full text
2020
Vanham, Davy | Leip, Adrian
Sustainable food system policies need to address environmental pressures and impacts: The example of water use and water stress Full text
2020
Vanham, Davy | Leip, Adrian
Sustainable food systems are high on the political and research agendas. One of the three pillars of sustainability is environmental sustainability. We argue that, when defining related policies, such as policies under the European Green Deal, both environmental pressures and impacts carry important and complementary information and should be used in combination. Although the environmental focus of a sustainable food system is to have a positive or neutral impact on the natural environment, addressing pressures is necessary to achieve this goal. We show this by means of the pressure water use (or water footprint) and its related impact water stress, by means of different arguments: 1) Water use and water stress are only weakly correlated; 2) water use can be evaluated towards a benchmark, addressing resource efficiency; 3) water use is used for resource allocation assessments within or between economic sectors; 4) water amounts are needed to set fair share amounts for citizens, regions, countries or on a global level 5) the pressure water use requires less data, whereas water stress assessments have more uncertainty and 6) both provide strong communication tools to citizens, including for food packaging labelling. As a result, we present a water quantity sustainability scheme, that addresses both water use and water stress, and can be used in support of food system policies, including food package labelling.
Show more [+] Less [-]Sustainable food system policies need to address environmental pressures and impacts: The example of water use and water stress Full text
2019
VANHAM Davy | LEIP Adrian
Sustainable food systems are high on the political and research agendas. One of the three pillars of sustainability is environmental sustainability. We argue that, when defining related policies, such as policies under the European Green Deal, both environmental pressures and impacts carry important and complementary information and should be used in combination. Although the environmental focus of a sustainable food system is to have a positive or neutral impact on the natural environment, addressing pressures is necessary to achieve this goal. We show this by means of the pressure water use (or water footprint) and its related impact water stress, by means of different arguments: 1) Water use and water stress are only weakly correlated; 2) water use can be evaluated towards a benchmark, addressing resource efficiency; 3) water use is used for resource allocation assessments within or between economic sectors; 4) water amounts are needed to set fair share amounts for citizens, regions, countries or on a global level 5) the pressure water use requires less data, whereas water stress assessments have more uncertainty and 6) both provide strong communication tools to citizens, including for food packaging labelling. As a result, we present a water quantity sustainability scheme, that addresses both water use and water stress, and can be used in support of food system policies, including food package labeling. | JRC.D.2 - Water and Marine Resources
Show more [+] Less [-]Diseño de un calentador de agua de alimentación a una caldera para una central térmica | Design of a feed-water heater for a thermal power station Full text
2020
García Quintanilla, Neco | Castro Alonso, Pablo Bernardo | Alechiguerra Sánchez, Iván | Universidad de Cantabria
Resumen: El presente proyecto nace de la necesidad de conocer el funcionamiento de un calentador de agua, así como determinar y describir sus partes integrantes con el propósito de adquirir los conocimientos necesarios para diseñar y proyectar dicho equipo para la producción de electricidad en una Central Térmica. El trabajo fin de grado consta de ocho capítulos y tres anexos (A, B y C) , a continuación resumen los más representativos : 1. Introducción: En este apartado se describe el equipo a presión dentro del ciclo termodinámico y se explica la importancia dentro de este. 2. Objetivos y Alcance: Marca el objetivo fundamental que consiste en la descripción del diseño en base a la normativa vigente. 3. Exposición General de un Feed-Water Heater: En este punto se explica detalladamente cada una de las partes integrantes del equipo a diseñar, a demás de los tipos de calentadores existentes. 4. Descripción del diseño del calentador: Una vez se explican cada una de las partes integrantes del equipo a diseñar, este capitulo se encarga de los siguientes objetivos: a. Situar el equipo dentro del ciclo termodinámico de la central. b. Definir las condiciones de contorno del calentador (temperaturas, presiones, flujos masicos…etc) , es decir , se obtienen todos los parámetros necesarios de partida para poder diseñar el calentador. c. Descripción del diseño térmico que utilizan los programas actuales para diseñar este tipo de equipos en base a la normativa vigente incluyendo formulas, tablas y conocimientos básicos en base a la experiencia para un correcto diseño térmico. d. Descripción del diseño mecánico que utilizan los programas actuales para diseñar este tipo de equipos en base a la normativa vigente incluyendo formulas, tablas y conocimientos básicos en base a la experiencia para una fabricación optima en consonancia con el previo diseño térmico. 5. Resultados del diseño y Anexos B y C: Tras recibir los datos necesarios para diseñar el equipo por parte de la central térmica de costanera mostrados en el anexo B (tablas de datos de la central) , el programa de cálculo térmico realiza el cálculo optimo del equipo dando una tabla de datos como resultado conocida como data sheet, es donde se muestran los parámetros térmicos fundamentales como área de intercambio de cada zona , espesores , materiales…etc. El anexo B también muestra la tabla de datos del diseño mecánico que recoge los espesores mas significativos del equipo según los requerimientos de diseño. El anexo C muestra dos planos característicos del equipo, siendo estos resultados del diseño imprescindibles para la fabricación del mismo. 6. Análisis Económico: Determina los costes y amortización del calentador por parte de la central térmica. 7. Conclusiones: En estas se defiende: a. Materiales Elegidos. b. Coste del calentador de agua de alimentación. | Abstract: This project is born from the need to know the operation of a water heater, as well as determine and describe its integral parts in order to acquire the necessary knowledge to design and project such equipment for the production of electricity in a Thermal Power Plant. The final degree project consists of eight chapters and three annexes (A, B and C), below summarize the most representative: 1. Introduction: This section describes the pressure equipment within the thermodynamic cycle and explains the importance within it: 2. Objectives and Scope: Mark the fundamental objective that consists in the description of the design based on current regulations. 3. General Exhibition of a Feed-Water Heater: This section explains in detail each of the integral parts of the equipment to be designed, in addition to the types of existing heaters. 4. Description of the heater design: Once each of the components of the equipment to be designed is explained, this chapter takes care of the following objectives: a. Place the equipment within the thermodynamic cycle of the plant. b. Define boiler boundary conditions (temperatures, pressures, mass flows ... etc), that is, all necessary starting parameters are obtained to be able to design the boiler. c. Description of the thermal design used by current programs to design this type of equipment based on current regulations including formulas, tables and basic knowledge based on experience for proper thermal design. d. Description of the mechanical design used by current programs to design this type of equipment based on current regulations including formulas, tables and basic knowledge based on experience for optimal manufacturing in line with the previous thermal design. 5. Design results and Annexes B and C: After receiving the necessary data to design the equipment by the waterfront thermal power plant shown in Annex B (data tables of the plant), the thermal calculation program performs the calculation optimum of the equipment giving a data table as a result known as data sheet, is where the fundamental thermal parameters are shown as the exchange area of each zone, thicknesses, materials ... etc. Annex B also shows the mechanical design data table that includes the most significant thicknesses of the equipment according to the design requirements. Annex C shows two characteristic drawings of the equipment, these design results being essential for its manufacture. 6. Economic Analysis: Determines the costs and amortization of the heater by the thermal power plant. 7. Conclusions: These are defended: a. Chosen Materials. b. Feed water heater cost. | Grado en Ingeniería de los Recursos Energéticos
Show more [+] Less [-]Toxoplasmose e sua transmissão por alimentos e água Full text
2020
Flores, Larissa Gais | Cardoso, Marisa Ribeiro de Itapema
A toxoplasmose é uma zoonose causada pelo protozoário Toxoplasma gondii, que tem como hospedeiros definitivos os felídeos e diversas espécies animais como hospedeiros intermediários. No hospedeiro definitivo ocorre o ciclo intestinal, a qual resulta na produção de oocistos eliminados nas fezes. Nos hospedeiros intermediários, incluindo o homem, ocorre o ciclo extra-intestinal, formando cistos teciduais. Os felídeos eliminam pelas fezes milhões de oocistos não esporulados durante a primo-infecção, sendo esta fase auto-limitante. A esporulação ocorre no ambiente em três a cinco dias, quando em temperatura ótima. Mesmo que os felinos domésticos tenham um importante papel na manutenção no ciclo de vida do toxoplasma, o contato direto com os gatos não é elo importante da transmissão. Os casos humanos estão frequentemente associados ao consumo de alimentos: de origem vegetal ou água contaminados com oocistos eliminados por felídeos ou produtos de origem animal com presença de cistos. A toxoplasmose tem grande importância em saúde pública, pois é uma das zoonoses mais difundidas no mundo. Diversos animais (cerca de 30 espécies de aves e 300 de mamíferos), assim como humanos, podem sofrer a infecção. A soroprevalência em humanos é elevada, pois estima-se que até um terço das pessoas do mundo sejam soropositivas, apresentando a forma de infecção crônica assintomática. A primo-infecção de gestantes representa grande risco, podendo ocorrer a transmissão fetal que leva a lesões no sistema nervoso central, devido ao tropismo do protozoário por esse tecido, podendo ser fatal. Também é um problema para pacientes com imunocomprometimento severo, nos quais causa sintomas graves. A doença ocular é provavelmente a manifestação sintomática, potencialmente grave, mais comum em toxoplasmose aguda pós-natal. A retinocoroidite toxoplasmática pode ser devido a doença congênita ou adquirida pós-natal e pode estar associada com a infecção aguda ou reativação. Mesmo assim, a toxoplasmose é considerada uma zoonose ainda negligenciada no Brasil, é preocupante o fato de não existir uma política pública que faça com que os médicos dediquem mais atenção a essa doença. Apenas recentemente a toxoplasmose congênita tornou-se um agravo de notificação obrigatória. Principalmente considerando que sua transmissão através do consumo de alimentos e água contaminados estiveram associados a surtos envolvendo grande número de acometidos no país. | Toxoplasmosis is a zoonosis caused by the protozoan Toxoplasma gondii, which has felids as the definitive host; and several animal species as intermediary hosts. The intestinal cycle occurs in the definitive host, which results in the production of oocysts eliminated in the feces. In the intermediary hosts, including man, the extra intestinal cycle occurs by forming tissue cysts. Felids eliminate millions of non-sporulated oocysts in the feces during the primary infection, and this phase is self-limiting. Sporulation occurs in the environment in 3 to 5 days, when at optimum temperature. Even though domestic cats play an important role in maintaining the toxoplasma life cycle, direct contact with cats is not an important link in transmission. Human cases are often associated with the consumption of food: vegetables or water contaminated with oocysts eliminated by felids or products of animal origin with the presence of cysts. Toxoplasmosis is of great importance in public health, since it is one of the most widespread zoonosis in the world. Several animals (about 30 species of birds and 300 of mammals), as well as humans, can suffer from the infection. Seroprevalence in humans is high, and it is estimated that up to a third of the global population may be seropositive and present an asymptomatic chronic infection. The primary infection of pregnant women represents a great risk, and transmission to the fetus may occur, which leads to lesions in the central nervous system, due to the tropism of the protozoan for this tissue. This infection form can be fatal. It is also a hazard for immunocompromised patients, in which it causes severe symptoms. Eye disease is probably the most common potentially severe symptomatic manifestation in acute postnatal toxoplasmosis. Toxoplasmic retinochoroiditis can be due to a congenital or acquired postnatal disease and can be associated with an acute infection or reactivation. In spite of that, toxoplasmosis is a zoonosis still neglected in Brazil, it is worrying that there is no public policy that makes doctors pay more attention to this disease. It is only recently that congenital toxoplasmosis has become a disease of mandatory notification. Especially considering that its transmission through the consumption of contaminated food and water has been associated with outbreaks involving a large number of people affected in the country.
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