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41.
食品安全管理存在问题及其对策研究   总被引:11,自引:1,他引:11  
食品是人类赖以生存和发展的重要物质基础。当前食品安全形势严峻,面临来自多方面的挑战。食物中毒、滥用杀虫剂、采用新技术和新工艺等带来的食品安全问题,还有生产流通环节的问题。笔者论述了食品安全的定义及内涵;介绍国内、外食品安全现状的基础上,分析了食品安全的重要性;进而提出了食品安全的可行性对策:完善我国食品安全法律法规与标准体系,建立和健全食品安全管理的专门机构,加强食品流通秩序的管理,构建系统的食品安全教育培训体系,加强社会监督,发挥消费者在食品安全问题中的积极作用等。  相似文献   
42.
This paper explores linkages between food security and crisis in different contexts, outlining the policy and institutional conditions needed to manage food security during a crisis and to rebuild the resilience of food systems in periods of relative peace. The paper reviews experiences over the past decade of countries in protracted crisis and draws lessons for national and international policy. It assesses the different alternatives on offer in fragile countries to address, for example, the disruption of institutional mechanisms and the decreasing level of support offered by international donors with respect to longer-term expectations. It proposes a Twin Track Approach to enhance food security resilience through specific policies for protracted crises that link immediate hunger relief interventions with a long-term strategy for sustainable growth. Finally, the article analyses policy options and the implications for both short- and longer-term responses vis-à-vis the three dimensions of food security: availability; access; and stability.  相似文献   
43.
气浮+生物接触氧化工艺处理食品加工废水   总被引:2,自引:0,他引:2  
通过气浮 生物接触氧化工艺处理速冻食品加工废水的实验、设计和工程运行,结果表明:废水COD去除率能达到97%以上,使得最终出水的COD<100mg/l.该工艺对冲击负荷有较强的适应性.  相似文献   
44.
How do youth learn through participation in efforts to study and change the school food system? Through our participatory youth action research (YPAR) project, we move beyond the “youth as consumer” frame to a food justice youth development (FJYD) approach. We track how a group of youth learned about food and the public policy process through their efforts to transform their own school food systems by conducting a participatory evaluation of farm-to-school efforts in collaboration with university and community partners. We used the Photovoice research method, placing cameras in the hands of young people so that they themselves could document and discuss their concerns and perspectives. The research was designed to gain insight about youths’ knowledge of food, health, and community food systems. Drawing upon the youth group’s insights, we build a framework for building critical consciousness through FJYD.  相似文献   
45.
应用自动化前处理设备和气相色谱串联四级杆质谱仪建立了淡水鱼体中10种有机磷阻燃剂的检测方法。该方法先采用自动索氏提取仪进行样品的提取,再应用凝胶渗透色谱净化仪和florisil柱对提取液进行两级净化,最后用气相色谱串联四级杆质谱法(多反应监测模式)对样品中的有机磷阻燃剂(OPFRs)定性定量。实验表明,凝胶渗透色谱净化系统在以乙酸乙酯∶环己烷(1∶1,V/V)为流动相,流速为5.0 m L·min-1的条件下,收集OPFRs的最佳时间为900~1 680 s;方法的检出限为0.002~0.192 ng·g~(-1)湿重,加标水平为5.000 ng·g~(-1)湿重时,平均加标回收率为48.7%~122%,相对偏差除磷酸三乙酯(TEP)(17.7%)和磷酸三(1,3-二氯异丙基)酯(TDCP)(11.9%)外均小于10%。应用该方法测定采集于东江某污水处理厂入河排污口的鱼类样品时,回收率指示物(d27-TBP)的回收率为82.4%~114%,鱼类样品中∑OPFRs的浓度范围为nd~6.41 ng·g~(-1)湿重。  相似文献   
46.
Although fish is a healthy alternative for meat, it can be a vehicle for mercury (Hg), including in its most toxic organic form, methylmercury (MeHg). The objective of the present study was to estimate the risk to human health caused by the consumption of sushi and sashimi as commercialized by Japanese food restaurants in the city of Campinas (SP, Brazil). The total Hg content was determined by atomic absorption spectrometry with thermal decomposition and amalgamation, and the MeHg content calculated considering that 90% of the total Hg is in the organic form. The health risk was estimated from the values for the provisional tolerable weekly ingestion (PTWI) by both adults and children. The mean concentrations for total Hg were: 147.99, 6.13, and 3.42 µg kg?1 in the tuna, kani, and salmon sushi samples, respectively, and 589.09, 85.09, and 11.38 µg kg?1 in the tuna, octopus and salmon sashimi samples, respectively. The tuna samples showed the highest Hg concentrations. One portion of tuna sashimi exceeded the PTWI value for MeHg established for children and adults. The estimate of risk for human health indicated that the level of toxicity depended on the type of fish and size of the portion consumed.  相似文献   
47.
The aim of the research is to evaluate pesticide residue contamination of fresh and frozen fruits and vegetables, agricultural raw material, purchased from Polish farmers for production of frozen fruits and vegetables, and the estimation of the multiresidue method effectiveness expressed as the proportion of pesticides detected in food samples to the total number of pesticides analyzed by multiresidue methods. A total of 144 samples (of black currants, red currants, raspberries, cherries, strawberries, blackberries, cauliflowers and broccoli) were analyzed using LC-MS/MS method for the determination of 60 pesticides. QuEChERS extraction, matrix-matched calibration and dynamic multiple reaction monitoring method were used. Residues of 15 compounds, mainly fungicides and insecticides, were detected in 46 samples. The percentage of samples with residues above the maximum residue levels (MRL) was 15%, whereas samples with residues below MRL were 17%. A total of 13 samples contained more than one pesticide residue. Pesticide residues were detected most often in samples of black currants (50%), broccoli (36.4%), raspberries (29%) and red currants (21.8%). The most frequently detected pesticides were carbendazim and acetamiprid. The proportion of pesticides detected during our study to the total number of analyzed pesticides amounted to 25%. It was compared to literature findings. For three fourth of multiresidue methods, the proportion was below 50% for methods developed for the analysis of less than 100 pesticides, and below 30% for methods developed for the analysis of more than 100 pesticides. It appears that a lot of efforts and means is lost on pesticides never or rarely detected in examined samples. The workload and cost effectiveness of the development and application of multiresidue methods along with the range of pesticides covered by the method should be carefully and thoroughly considered anytime when a new method or workflow is developed. Including non-targeted screenings in pesticide residue control seems to be an alternative worth considering.  相似文献   
48.
One in 6 species (13,465 species) on the International Union for Conservation of Nature (IUCN) Red List is classified as data deficient due to lack of information on their taxonomy, population status, or impact of threats. Despite the chance that many are at high risk of extinction, data‐deficient species are typically excluded from global and local conservation priorities, as well as funding schemes. The number of data‐deficient species will greatly increase as the IUCN Red List becomes more inclusive of poorly known and speciose groups. A strategic approach is urgently needed to enhance the conservation value of data‐deficient assessments. To develop this, we reviewed 2879 data‐deficient assessments in 6 animal groups and identified 8 main justifications for assigning data‐deficient status (type series, few records, old records, uncertain provenance, uncertain population status or distribution, uncertain threats, taxonomic uncertainty, and new species). Assigning a consistent set of justification tags (i.e., consistent assignment to assessment justifications) to species classified as data deficient is a simple way to achieve more strategic assessments. Such tags would clarify the causes of data deficiency; facilitate the prediction of extinction risk; facilitate comparisons of data deficiency among taxonomic groups; and help prioritize species for reassessment. With renewed efforts, it could be straightforward to prevent thousands of data‐deficient species slipping unnoticed toward extinction.  相似文献   
49.
Food and food-related waste is a high priority in terms of waste minimisation in New Zealand. Over the summer of 2012–2013, a survey of 147 participants was conducted on a range of views and practices related to environmental challenges and understandings. The survey, undertaken in Palmerston North, New Zealand, captured a wide socio-demographic. This article focuses on respondents’ food practices from purchase, to plate, to disposal and the environmental implications of these practices. The survey data have allowed an enriched understanding of both individual and structural level challenges as well as incentives towards improving environmental practices in relation to household food waste minimisation. The results indicated that, in keeping with other research in this area, food waste increases according to the number of individuals in a household, and in particular the number of younger people. Also, while the majority of participants were at least “somewhat concerned” about their households’ environmental impact, over three quarters of participant households put food waste into their rubbish bin. Some solutions and directions to further progress research, policy, and practice in this area are offered, and include the need for more direct and personalised communication regarding waste minimisation, along with the provision of kerbside food waste collections. It is clear that individual- or household-level changes are important and must be supported systemically by both local body and state level legislation and initiatives, if there is to be any substantial decline in food waste going to landfill.  相似文献   
50.
This paper discusses the extent to which charity-led initiatives can contribute to capacity building for food justice in England. The paper draws on evaluations of two projects run by the charity Garden Organic: the Master Gardener Programme, operating a network of volunteers who mentor households, schools and community groups to support local food growing, and the Sowing New Seeds programme, which engages “Seed Stewards” to work with communities to encourage the growing and cooking of “exotic” crops. Based on qualitative data about peoples’ motivations for participation and the benefits that are experienced, we interpret these projects as examples of capacity building for food justice. We suggest that whilst currently depoliticised, the “quiet” process of reskilling and awareness raising that occurs through shared gardening projects could have transformative potential for people’s relationship with food. Finally, we use our findings to raise critical questions and propose future research about food justice concepts and practices.  相似文献   
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