Evaluation of nitrate and nitrite content in diets of preschool children]

The nitrate and nitrite contents in diets of preschool children were evaluated. The meals were taken from one of the kindergarten near Warsaw. Colorimetric method with Griess reagent and cadmium column for nitrates reduction was used. It was seen, that diets contained to much of nitrates and nitrites as to ADI. The main sources of these compound were vegetables, potatoes, meat and meat products and cereals.     

英蓝超滤-离子色谱法同时测定熟肉制品中硝酸盐和亚硝酸盐含量

目的建立离子色谱法同时测定熟肉制品中的硝酸盐和亚硝酸盐含量的方法。方法样品经过去除脂肪和蛋白质后,选用3.2 mmol/LNa2CO3和1.0 mmol/LNa HCO3作淋洗液,0.6 m L/min流速,电导检测器,样品采用英蓝超滤装置过滤后直接进样。结果采用本方法测定熟肉制品中的硝酸盐和亚硝酸盐含量,结果相关性好(r0.999),精密度高(RSD3.2%),加标回收率为82.8%~94.0%,准确度高。结论该方法操作简便,快速,灵敏度高,适用于大批量样品的分析。     

2011年云南省市售熟肉制品中硝酸盐和亚硝酸盐含量检测结果分析

目的:了解2011年云南省市售熟肉制品中硝酸盐和亚硝酸盐含量,为加强食品安全管理监督提供科学依据。方法:根据GB/T5009.33-2010《食品中亚硝酸盐和硝酸盐的测定》采用分光光度法对抽检样品的硝酸盐和亚硝酸盐进行检测,并对检测结果进行统计分析。结果:本次抽检的191件熟肉样品中,硝酸盐检出率100%,合格率28.8%。亚硝酸盐的平均检出率85.3%,合格率99.5%。结论:在云南省市售熟肉制品的加工生产过程中,硝酸盐的使用普遍而且量大。亚硝酸盐的使用普遍但比较规范,基本按照食品添加剂的安全标准规定的允许量添加。     

Evaluation of nitrate and nitrite accumulation in drinking water supplies]

Levels of the nitrate and nitrite content in water sources of Kiev and Cherkassy regions were studied. Highest concentrations of nitrite (1.33 mg N/l) and nitrate (168 mg N/l) were defined in local water sources. Peculiarity of nitrate and nitrite distribution is discussed.     

南通市2008年-2011年市售熟肉制品中亚硝酸盐含量的调查分析

目的:了解南通市市场上熟肉制品中亚硝酸盐含量情况,为政府相关部门提供卫生监管的依据。方法:对市场上抽检的423份样品中亚硝酸盐的监测结果进行统计与分析。结果:亚硝酸盐含量的检出率57.45%,合格率为96.93%,超标率为3.07%,定型包装的合格率高于非定型包装,定型包装的合格率100%,调查中最高含量达3200 mg/kg,超过国家限量标准100倍。结论:南通市市售熟肉制品中存在普遍使用亚硝酸盐的情况,部分样品还存在超标使用和滥用亚硝酸盐的状况,提示应引起相关部门的重视,加大监督力度,以提高熟肉制品的食用安全性。     

2011—2012年大连市熟肉制品亚硝酸盐含量监测结果分析

目的了解大连市熟肉制品中亚硝酸盐含量。方法按照《大连市食品安全风险监测实施方案》要求,对2011—2012年采集的160份熟肉制品进行亚硝酸盐含量检测。结果亚硝酸盐检出率为59．4％,超标率为6．2％,最大值121．7me,／kg;10份超标样品为6份酱卤肉制品与4份熏烤肉制品;散装样品检出率为70．5％,定型包装检出率为38．2％,两者检出率差异具有统计学意义（P〈0．01）。结论亚硝酸盐在熟肉制品加工中使用较为普遍,在农贸市场上销售的散装熟肉制品中亚硝酸盐含量超标风险较高。     

Nitrate and nitrite content in potatoes from ecological and conventional farms]

The aim of this investigation was to determine nitrate and nitrite content in potatoes from ecological and conventional farms. The influence of variety on nitrate and nitrite content was also evaluated. Vegetables and potatoes from ecological cultures are supposed to contain less nitrates and nitrites and on this basis could have been advised for children, sick and people in special physiological stages. Nitrite content was determined colorimetrically, with sulfanilic acid, nitrate content was determined following reduction of nitrites by means of metallic cadmium. The results showed significantly lower nitrate content in potatoes from ecological farms, and almost twice higher in those from conventional farms. The nitrite content showed no differentiation in conventional and ecological farms. Within three varieties of potatoes (sokó?, bryza, ania) significantly highest content of nitrate was determined in bryza. Considering low nitrate level potatoes from ecological farms could be advised for children and sick people, but for the complete safety evaluation also content of other contaminants (i.e. heavy metals) have to be assessed.     

The effect of dietary nitrate on nitrate and nitrite excretion in man

Dietary nitrate and nitrite may affect colonic pathophysiology. These anions influence fermentation, and nitrite has been shown to augment sodium absorption by the colon and participate in the formation of N-nitroso compounds. There is, however, no general agreement as to how much dietary nitrate and nitrite reaches the colon. To help resolve this question, balance studies were performed on six healthy ileostomy subjects who were given diets that varied in nitrate content from 0.83 to 5.20 mmol/d. Nitrate and nitrite excretion in ileal effluent and urine were measured by anion-exchange chromatography with conductivity detection. There was no significant nitrite in the diets, urine or ileal effluent. Dietary nitrate was largely excreted in urine (1.31-4.25 mmol/d). The urinary excretion findings indicated net synthesis of nitrate at low dietary intakes and net catabolism of nitrate at high intakes. Nitrate losses in ileal effluent were very low (0.03-0.05 mmol/d, 0.03-0.06 mmol/kg) and unrelated to intake for all the diets. It is concluded that dietary nitrate and nitrite do not enter the colon from the small intestine in amounts that would affect fermentation and mucosal metabolism in man. The possibility of significant amounts of nitrate reaching the colon via blood in normal subjects has not been excluded.     

How to reduce the nitrate content in baby foods]

Nitrates content in baby food must not exceed 50 mg/kg according to the new french legislation. The amount found in fresh vegetable are often higher. Technological methods to reduce this amount eliminate also vitamins, minerals and carbohydrates. For this reason, we are looking for agronomics methods to get lower quantities of nitrates.     

Accumulations of nitrite and nitrate in the tissues of Penaeus monodon exposed to a combined environment of elevated nitrite and nitrate

Penaeus monodon (11.86 ± 0.63 g) exposed individually to six different nitrite and nitrate regimes [nitrite at 0.002 (control), 0.360, and 1.455 mM combined with nitrate at 0.005 (control) and 7.275 mM] in 25 ppt sea water were examined for the nitrite and nitrate concentrations in tissues and nitrite uptake and nitrate uptake after 24 h in 25.3°C. In P. monodon following exposure to 1.455 mM nitrite only, nitrite levels increased by factors of 0.33, 1.05, 1.36, 1.79, 2.10, 2.16, 2.21, and 3.58 in muscle, hepatopancreas, gill, foregut, hemolymph, heart, eyestalk, and midgut, respectively, over the ambient nitrite level. In P. monodon, following exposure to combined solutions of 1.455 mM nitrite and 7.275 mM nitrate, nitrite levels were factors of 0.34, 1.05, 1.44, 1.86, 2.21, 2.30, 2.67, and 3.83 in muscle, hepatopancreas, gill, foregut, heart, hemolymph, eyestalk, and midgut, respectively, over the ambient nitrite levels, whereas nitrate levels were factors of 0.06, 0.11, 0.27, 0.29, 0.45, 0.51, 0.57, and 0.61 in muscle, hepatopancreas, foregut, heart, hemolymph, gill, midgut, and eyestalk, respectively, over the ambient nitrate levels. It is concluded that incorporation of nitrite is converted to nitrate in midgut, heart, hemolymph, foregut, and eyestalk, whereas incorporation of nitrate in tissues is converted to nitrite and accumulated in eyestalk when P. monodon are exposed to combined nitrite and nitrate environments. Received: 1 June 2001/Accepted: 7 January 2002     

2012—2015年中国熟肉制品中亚硝酸盐含量

目的了解中国熟肉制品中亚硝酸盐的含量。方法 2012—2015年采集中国流通环节和餐饮环节的熟肉制品,采用国标GB 5009.33—2010方法对样品中的亚硝酸盐含量进行检测,采用GB 2760—2014《食品安全国家标准食品添加剂使用标准》进行判定。结果 2012—2015年共检测熟肉制品19 360份,亚硝酸盐的平均值为9.7 mg/kg,含量范围为未检出～85.3 mg/kg,超标率为4.8%(922/19360),各类熟肉制品中,内脏的亚硝酸盐平均含量最高为16.6 mg/kg,农贸市场的超标率显著高于其他采样环节,散装样品的超标率为定型包装的5.8倍。四年间超标率呈逐年下降趋势,主要问题是农贸市场的散装酱卤肉制品,超标率为9.5%(327/3461)。结论目前中国市场上熟肉制品中的亚硝酸盐总体使用情况较好,散装样品是超标的主要问题,熟肉制品中来源于亚硝酸盐的风险较低。     

2011-2013年新乡市熟肉制品中亚硝酸盐含量监测分析

目的了解新乡市市场上熟肉制品中亚硝酸盐含量情况。方法 2011年-2013年连续3年对市场上抽检熟肉样品中亚硝酸盐含量的监测结果进行统计和分析。结果连续3年检测熟肉制品共计421份,熟肉制品亚硝酸盐含量总合格率为79.3%。其中熟鸡肉和熟鸭肉亚硝酸盐含量总合格率分别是97.1%,96.4%,熟牛肉和熟猪肉亚硝酸盐含量总合格率分别只有76.9%,72.7%。结论新乡市市售熟肉制品中还存在超标使用和滥用亚硝酸盐的状况,特别是熟牛肉和熟猪肉中,建议引起有关部门的重视,加强监管,提高熟肉制品的食用安全性。     

反相高效液相色谱法同时测定酱腌菜中亚硝酸盐和硝酸盐

目的:建立反相高效液相色谱法测定酱腌菜中的亚硝酸盐与硝酸盐的方法.方法:样品经超声提取,再经石墨化炭黑柱(Envi-Carb柱)及PrelC-Ag和PrelC-Na联合柱净化处理后,以0.02 mol/L磷酸二氢钾一磷酸缓冲溶液(pH=3.20)为流动相,经Capcell PAK C18色谱柱分离,于210 nm处检测.结果:NO-2和NO3-在0.02～20 mg/L范围具有良好的线性,其相关系数均大于0.999,检出限均为0.8 mg/kg,实际样品的加标回收率分别为90.6%～101.3%和96.6%～104.8%,相对标准偏差≤5%.结论:此法简单、灵敏、准确,可用于同时测定酱腌菜中亚硝酸盐和硝酸盐.     

空气中亚硝酸盐和硝酸盐的离子色谱测定方法的研究

目的:建立空气中亚硝酸盐和硝酸盐的离子色谱测定方法。方法:本文采用超细玻璃纤维滤纸采集空气中亚硝酸盐和硝酸盐,用蒸馏水洗脱过滤后,经色谱柱分离,电导检测器检测,保留时间定性,峰高或峰面积定量。结果:空气中亚硝酸盐和硝酸盐的线性范围分别为0.5~30.0μg/m l和0.5~30.0μg/m l;相关系数分别为0.9997和0.9992;方法的最低检出限分别为0.5μg/m l和0.5μg/m l;若采集300 L空气进行测定,则最低检出浓度分别为0.017 mg/m3和0.017 mg/m3;相对标准偏差分别为0.39%~1.03%和0.45%~1.00%;样品洗脱效率分别为100.4%~103.2%和102.3%~106.8%;采样效率分别为94.8%~100.0%和92.7%~94.6%;样品在室温中至少可保存1周。结论:此法灵敏度高,选择性好,干扰少,是同时检测空气中亚硝酸盐和硝酸盐的好方法。     

Values of nitrate and nitrite in selected vegetables and potatoes cultivated in the region of Pu?aw]

Nitrate and nitrite contents were determined in selected vegetables and potatoes from plantations of individuals farmers, situated either in the vicinity of the Nitrogen Plant in Pu?awy or at a distance from this plant (control). Vegetables and potatoes both newly harvested and stored for 4 months in cellars were analysed. From farms selected by lot, samples of lettuce, cabbage, sauerkraut, beets, carrots and potatoes (all harvested in 1986 and 1987) were collected. Nitrate and nitrite contents were determined in 1215 plant samples. Nitrates were reduced on a cadmium column to nitrites, whereupon they were determined colorimetrically using sulphanilic acid and N-1-naphthylethylenediamine. This results showed that the nitrate contents are higher in the vegetables and potatoes cultivated in the region of the Nitrogen Plant, as compared with those from the Janowiec village distant from this plant (control). Differences in mean nitrate contents per 100 g dry matter were in years 1986 and 1987 for: lettuce 73%, 36%; cabbage 54%, 39%; beets 16%, 20%; carrots 51%, 29%; potatoes 77%, 36%, respectively. Moreover, the vegetables and potatoes grown in the region of the Nitrogen Plant, as compared with the control vegetables from the village located at a distance from this plant, displayed a greater percentage of samples with plants characterized by higher nitrate contents. The greater percentage of samples containing high nitrate levels, as well as the higher mean nitrate contents in vegetables and potatoes testify to the effect of the Nitrogen Plant on nitrate concentrations in the crops. In vegetables from both regions, the nitrite contents did not exceed 1 mg NaNO2/kg.(ABSTRACT TRUNCATED AT 250 WORDS)     

Dietary nitrate and nitrite intake and non-Hodgkin lymphoma survival

Nitrate and nitrite are precursors in the formation of N-nitroso compounds. We recently found a 40% increased risk of NHL with higher dietary nitrite intake and significant increases in risk for follicular and T-cell lymphoma. It is possible that these compounds also affect NHL prognosis by enhancing cancer progression in addition to development by further impairing immune system function. To test the hypothesis that nitrate and nitrite intake affects NHL survival, we evaluated the association in study participants that have been followed post-disease diagnosis in a population-based case-control study among women in Connecticut. We did not observe a significant increasing trend of mortality for NHL overall or by subtype for nitrate or nitrite intake for deaths from NHL or death from any cause, although a borderline significant protective trend was observed for follicular lymphoma with increasing nitrate intake. We did not identify a difference in overall survival for nitrate (P = 0.39) or for nitrite (P = 0.66) or for NHL specific survival for nitrate (P = 0.96) or nitrite (P = 0.17). Thus, our null findings do not confer support for the possibility that dietary nitrate and nitrite intake impacts NHL survival by promoting immune unresponsiveness.