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Национальные и международные правила, касающиеся уровней и типов энергии, используемой для облучения пищевых продуктов, как правило, устанавливают стандарты, которые предотвращают возможность возникновения радиоактивности в обработанных пищевых продуктах. Необходимо соблюдать осторожность, чтобы не подвергать операторов и окружающую среду воздействию радиации. Для минимизации этого риска предусмотрены блокировки и меры предосторожности. Тем не менее, имели место смерти и травмы, связанные с радиацией, среди работников таких объектов, многие из них были вызваны тем, что сами операторы перекрывали блокировки.[45]Инцидент в Декейтере, штат Джорджия, где водорастворимый цезий-137 просочился в хранилище источника, потребовав вмешательства NRC[46], привел к почти полному уничтожению этого радиоизотопа; он был заменен более дорогостоящим, нерастворимым в воде кобальтом-60.АльтернативыДругие методы борьбы с различными патогенами в пищевых продуктах включают термическую пастеризацию, обработку при сверхвысоких температурах, ультрафиолетовое излучение, озон или фумигацию окисью этилена.Насекомых-вредителей также можно уничтожить путем окуривания бромистым метилом или фосфином алюминия, нагреванием паров, принудительным подачей горячего воздуха, погружением в горячую воду или обработкой холодом. Однако долгоносик манго, сидящий в косточке плода, может быть поражен только ионизирующим излучением.Другие методы продления срока годности пищевых продуктов включают упаковку в модифицированной атмосфере, использование монооксида углерода, обезвоживание, вакуумную упаковку, замораживание и мгновенную заморозку, а также химические добавки. Однако такие методы неэффективны для продуктов, уже подвергнутых глубокой заморозке, когда в продукт может проникать только ионизирующее излучение (без повторного размораживания).Некоторые люди утверждают, что лучшей альтернативой облучению пищевых продуктов для уменьшения количества патогенных микроорганизмов является надлежащая сельскохозяйственная практика. Например, фермерам и перерабатывающим предприятиям следует улучшить методы санитарии, воду, используемую для орошения и переработки, следует регулярно проверять на наличие кишечной палочки, а производственные предприятия следует регулярно инспектировать. Следует регулировать операции по концентрированному кормлению животных вблизи сельскохозяйственных угодий, где выращивается продукция. Однако такие методы, которые также практикуются в органическом земледелии, могут только уменьшить нагрузку на почву микроорганизмами всех видов; остаточная флора, включающая патогенные микробы, всегда будет сохраняться; и обработка ионизирующим излучением может быть конечной мерой (как КПК в соответствии с концепцией ХАССП) для практического устранения таких рисков.
It has also been shown that irradiation can delay the ripening of fruits or the sprouting of vegetables. [1]Furthermore, insect pests can be sterilized using irradiation at relatively low doses[5]. In consequence, the United States Department of Agriculture has approved the use of low-level irradiation as an alternative treatment to pesticides for fruits and vegetables that are considered hosts to a number of insect pests, including fruit flies and seed weevils; US FDA has cleared among a number of other applications the treatment of hamburger patties to eliminate the residual risk of a contamination by a virulent E. coli. The United Nations Food and Agricultural Organization (FAO) has passed a motion to commit member states to implement irradiation technology for their national phytosanitary programs; the General assembly of the International Atomic Energy Agency (IAEA) has urged to make wider use of the irradiation technology; the World Health Organization (WHO) has complained that food irradiation is not available to those who need it most because of reluctance and opposition in some developed countries. And the USDA has made a number of bi-lateral agreements with developing countries to facilitate the imports of exotic fruits and to simplify the quarantine procedures.Currently, the European Union has regulated processing of food by ionizing radiation in specific directives since 1999; the situation is easily explored and the several documents and reports are accessible.[6] The 'implementing' directive contains a 'positive list' only permitting irradiation of dried aromatic herbs, spices, and vegetable seasonings[7]. However, any Member State is permitted to maintain previously granted clearances or to add new clearance as granted in other Member States, in the case the EC's Scientific Committee on Food (SCF) has given a positive vote for the respective application. Presently, six Member States (Belgium, France, Italy, Netherlands, Poland, United Kingdom) have adopted such provisions.[8]Because of the 'Single Market' of the EC, any food--even if irradiated--must be allowed to be marketed in any other Member State even if a general ban of food irradiation prevails, under the condition that the food has been irradiated legally in the state of origin. Furthermore, imports into the EC are possible from third countries if the irradiation facility had been inspected and licensed by the EC and the treatment is legal within the EC or some Member state[9] . The Scientific Committee on Food (SCF) of the EC has given a positive vote on eight categories of food to be irradiated[10]. However, in a compromise between the European Parliament and the European Commission, only dried aromatic herbs, spices, and vegetable seasonings can be found in the positive list. The European Commission was due to provide a final draft for the positive list by the end of 2000; however, this failed because of a veto from Germany and a few other Member States. In 1992[11] and in 1998[12] the SCF voted positive on a number of irradiation applications which had been allowed in some Member States before the EC Directives came into force, in order to enable those Member States to maintain the national authorizations. In 2003 (at the occasion when Codex Alimentarius was about to remove any upper dose limit for food irradiation) the SCF adopted a 'revised opinion'
[13] which in fact is just a re-confirmation and endorsement of the 1986-opinion. The cancellation of the upper dose limit is denied, and before the actual list of individual items or food classes (as in the opinions expressed in 1986, 1992 and 1998) is expanded, new individual studies into the toxicology of each of such food and for each of the proposed dose ranges is requested. After 2003 the SCF has been replaced by the new European Food Safety Authority (EFSA), which not yet has voted on processing food by ionizing radiation.Other countries including New Zealand, Australia, Thailand, India, and Mexico have permitted the irradiation of fresh fruits for fruit fly quarantine purposes amongst others. Other countries as Pakistan and Brazil have adopted the Codex Alimentarius Standard on Irradiated Food without any reservation or restriction, ie. any food to any dose.Radiation absorbed dose
Dose' is the physical quantity governing radiation processing of food and the beneficial effects to be achieved.
Food irradiation
Food irradiation[1] is the process of exposing food to ionizing radiation in order to destroy microorganisms, bacteria, viruses, or insects that might be present in the food. Further applications include sprout inhibition, delay of ripening, increase of juice yield, and improvement of re-hydration. Irradiation is a more general term of deliberate exposure of materials to radiation to achieve a technical goal (in this context 'ionizing radiation' is implied). As such it is also used on non-food items, such as medical hardware, plastics, tubes for gas-pipelines, hoses for floor-heating, shrink-foils for food packaging, automobile parts, wires and cables (isolation), tires, and even gemstones. Compared to the amount of food irradiated, the volume of those every-day applications is huge but not noticed by the consumer.The genuine effect of processing food by ionizing radiation relates to damages to the DNA, the basic genetic information for life. Microorganisms can no longer proliferate and continue their malignant or pathogen activities. Spoilage causing micro-organisms cannot continue their activities. Insects do not survive or become incapable of proliferation. Plants cannot continue the natural ripening or aging process. All these effects are beneficial to the consumer and the food industry, likewise.It should be noted that the amount of energy imparted for effective food irradiation is low compared to cooking the same; even at a typical dose of 10 kGy most food, which is (with regard to warming) physically equivalent to water, would warm by only about 2.5 °C.The speciality of processing food by ionizing radiation is the fact, that the energy density per atomic transition is very high, it can cleave molecules and induce ionization (hence the name) which cannot be achieved by mere heating. This is the reason for new beneficial effects, however at the same time, for new concerns. The treatment of solid food by ionizing radiation can provide an effect similar to heat pasteurization of liquids, such as milk. However, the use of the term, cold pasteurization, to describe irradiated foods is controversial, because pasteurization and irradiation are fundamentally different processes, although the intended end results can in some cases be similar.Food irradiation is currently permitted by over 40 countries and volumes are estimated to exceed 500 000 metric tons annually world wide. [2] [3] [4]Processing of food by ionizing radiation
By irradiating food, depending on the dose, some or all of the harmful bacteria and other pathogens present are killed. This prolongs the shelf-life of the food in cases where microbial spoilage is the limiting factor. Some foods (e.g., herbs and spices) are irradiated at sufficient doses (five kilograys or more) to reduce the microbial counts by several orders of magnitude; such ingredients will not carry over spoilage or pathogen microorganisms into the final product.It has also been shown that irradiation can delay the ripening of fruits or the sprouting of vegetables. [1]Furthermore, insect pests can be sterilized using irradiation at relatively low doses[5]. In consequence, the United States Department of Agriculture has approved the use of low-level irradiation as an alternative treatment to pesticides for fruits and vegetables that are considered hosts to a number of insect pests, including fruit flies and seed weevils; US FDA has cleared among a number of other applications the treatment of hamburger patties to eliminate the residual risk of a contamination by a virulent E. coli. The United Nations Food and Agricultural Organization (FAO) has passed a motion to commit member states to implement irradiation technology for their national phytosanitary programs; the General assembly of the International Atomic Energy Agency (IAEA) has urged to make wider use of the irradiation technology; the World Health Organization (WHO) has complained that food irradiation is not available to those who need it most because of reluctance and opposition in some developed countries. And the USDA has made a number of bi-lateral agreements with developing countries to facilitate the imports of exotic fruits and to simplify the quarantine procedures.Currently, the European Union has regulated processing of food by ionizing radiation in specific directives since 1999; the situation is easily explored and the several documents and reports are accessible.[6] The 'implementing' directive contains a 'positive list' only permitting irradiation of dried aromatic herbs, spices, and vegetable seasonings[7]. However, any Member State is permitted to maintain previously granted clearances or to add new clearance as granted in other Member States, in the case the EC's Scientific Committee on Food (SCF) has given a positive vote for the respective application. Presently, six Member States (Belgium, France, Italy, Netherlands, Poland, United Kingdom) have adopted such provisions.[8]Because of the 'Single Market' of the EC, any food--even if irradiated--must be allowed to be marketed in any other Member State even if a general ban of food irradiation prevails, under the condition that the food has been irradiated legally in the state of origin. Furthermore, imports into the EC are possible from third countries if the irradiation facility had been inspected and licensed by the EC and the treatment is legal within the EC or some Member state[9] . The Scientific Committee on Food (SCF) of the EC has given a positive vote on eight categories of food to be irradiated[10]. However, in a compromise between the European Parliament and the European Commission, only dried aromatic herbs, spices, and vegetable seasonings can be found in the positive list. The European Commission was due to provide a final draft for the positive list by the end of 2000; however, this failed because of a veto from Germany and a few other Member States. In 1992[11] and in 1998[12] the SCF voted positive on a number of irradiation applications which had been allowed in some Member States before the EC Directives came into force, in order to enable those Member States to maintain the national authorizations. In 2003 (at the occasion when Codex Alimentarius was about to remove any upper dose limit for food irradiation) the SCF adopted a 'revised opinion'
[13] which in fact is just a re-confirmation and endorsement of the 1986-opinion. The cancellation of the upper dose limit is denied, and before the actual list of individual items or food classes (as in the opinions expressed in 1986, 1992 and 1998) is expanded, new individual studies into the toxicology of each of such food and for each of the proposed dose ranges is requested. After 2003 the SCF has been replaced by the new European Food Safety Authority (EFSA), which not yet has voted on processing food by ionizing radiation.Other countries including New Zealand, Australia, Thailand, India, and Mexico have permitted the irradiation of fresh fruits for fruit fly quarantine purposes amongst others. Other countries as Pakistan and Brazil have adopted the Codex Alimentarius Standard on Irradiated Food without any reservation or restriction, ie. any food to any dose.Radiation absorbed dose
Dose' is the physical quantity governing radiation processing of food and the beneficial effects to be achieved.