Daily Intake Of Nitrate Research Articles

Groundwater Contamination with Nitrate and Human Health Risk Assessment of North East Alluvial Plains of Bihar, India

Groundwater is natural resources which supplies almost half of all drinking water in the world and plays a key role in food production. Consuming water containing high nitrate concentration have immediate effect on infant and could cause the risk of diseases Methemoglobinemia in which blood lacks the ability to carry sufficient oxygen to the individual body cells. As difference in nitrate concentration in water, made it important to study the undesirable effect of it. In rural areas, groundwater contamination is a problem related to the excessive use of chemical fertilizers by local farmers. Shallow groundwater plays a vital role in water use and the yield of Maize. Nitrogen application significantly affects crop uptake and utilization of water from irrigation, but little is known about groundwater use. Farmers are applying nitrogen on an average 278 kg/ha in Kharif maize, which is about 131.72% more than the RDN of Kharif maize i.e. 120 KgN/ha. The mean value of N application by farmers ranges from 251-323 kg/ha. The Maximum rate of N application was observed in Khagaria (323 kg N/ha) followed by Madhepura (275.08 kg N/ha) and minimum in case of Saharsa district (251.16 kg N/ha). The application rate of nitrogenous fertilizer, varying from 109.25% to 169.16% over the RDN, resulting in NO3- leaching. The groundwater and surfacewater from 12 villages was collected and various quality parameters were analysed. The nitrate in ground water varied (1.87- 6.19 mg/L) and surface water (1.87 – 3.84 mg/L) being maximum concentration of nitrate in Madhepura district. The present study on nitrate leaching in soil, its level of contamination in ground water and human health risk assessment by chronic daily intake of nitrate and Hazard Quotient (H.Q) values in the study area of Khagaria, Saharsa, Madhepura and Supaul has been carried out in the eastern alluvial region of Bihar.

Effect of fly ash and bottom ash application as mix growing media on heavy metals status in vegetables

Coal fly ash-bottom ash (FABA) is still possible to be used directly as a mixture of soil with other growing media in small-scale agriculture. This study aimed to determine and to identify the level of safety for the consumption of vegetable crops related to the adsorption of heavy metals due to the use of mixed FABA planting media. In this study, the proportion mixture of 6% FABA, 6% compost, and 8.6% fine coal (lignite) was applicated. The proportion ratio between FABA and soil was 1:15. The FABA media application was prepared for eggplant, chili, water spinach, spinach, mustard greens, and moringa vegetables. The study was conducted without any control treatment without FABA on the same soil type. As an alternative control, vegetables from local farmers, local markets, and supermarkets surrounding the study site were taken. The experimental results showed that the application of FABA did not increase nitrate and heavy metals content in vegetables. It can be concluded that vegetables grown on FABA media were safe and suitable for consumption in terms of acceptable daily intake of nitrate and various heavy metals, except for As intake in water spinach and mustard greens, which were recommended to be confirmed in further determination research.

The Effects of Nitrate Supplementation on Performance as a Function of Habitual Dietary Intake of Nitrates: A Randomized Controlled Trial of Elite Football Players.

Nitrates are an effective ergogenic supplement; however, the effects of nitrate supplements based on habitual dietary nitrate intake through diet alone are not well understood. We aimed to assess this in a group of 15 highly trained football players from Slovenian football's First Division. Participants underwent two separate Cooper performance tests either with nitrate supplementation (400 mg nitrates) or placebo while having their nutrition assessed for nitrate intake, as well as energy and macronutrient intake. Nitrate supplementation had a statistically significant positive effect on performance if baseline dietary nitrate intake was below 300 mg (p = 0.0104) in both the placebo and intervention groups. No effects of nitrate supplementation when baseline dietary nitrate intake was higher than 300 mg in the placebo group could be concluded due to the small sample size. Nitrate supplementation did not have a significant effect on perceived exertion. The daily nitrate intake of the participants was measured at 165 mg, with the majority of nitrates coming from nitrate-rich vegetables.

Nitrate Quantification in Fresh Vegetables in Shanghai: Its Dietary Risks and Preventive Measures.

To investigate nitrate and nitrite content in fresh vegetables, 264 samples were randomly collected in the farmers' markets in Shanghai, Southeast China. The results indicate that 25.0% of the fresh vegetables were critically or more contaminated by nitrate [>1440 mg/kg FW (Fresh weight)]. Generally, leafy vegetables were more highly enriched in nitrate than root-tuber and fruit vegetables. About 22.6% of the leafy vegetables had a nitrate content exceeding the limit for edible permission (>3000 mg/kg FW). Nitrite content in the fresh vegetables was all within the safe level (<1 mg/kg FW). It was estimated that the daily nitrate intake through eating vegetables in Shanghai exceeded the WHO/FAO allowable limit. The field experiment indicated that the hyper-accumulation of nitrate and nitrite in the vegetables was mainly attributed to the excessive application of chemical fertilizers. The maxima of nitrate and nitrite in the vegetables were attained one week after applying chemical fertilizer, and thus they cannot be picked for dietary use. Applying organic manure can effectively lower the risk of nitrate and nitrite contamination in vegetables. The old leaves and leaf petioles were more easily enriched in nitrate due to their weaker metabolic activity. Vegetables with high nitrate content had a high risk of nitrite toxicity during storage due to the biological conversion of nitrate into nitrite, which is easily triggered by suitable temperature and mechanical damage processing. Therefore, fresh vegetables should be stored by rapid cooling and in undamaged forms to prevent nitrite accumulation.

Nitrate in groundwater and agricultural products: intake and risk assessment in northeastern Iran

The suitability of groundwater and agricultural products for human consumption requires determining levels and assessing the health risks associated with potential pollutants. Here, particularly pollution with nitrate still remains a challenge, especially for those urban areas suffering from insufficient sewage collection systems, resulting in contaminating soil, endangering food safety, and deteriorating drinking water quality. In the present study, nitrate concentrations in the commonly consumed fruit and vegetable species were determined, and the results, together with the groundwater nitrate levels, were used to assess the associated health risks for Mashhad city residents. For this assessment, 261 water samples and 16 produce types were used to compute the daily intake of nitrate. Nitrate in groundwater was analyzed using a spectrophotometer, and produce species were examined using High-Performance Liquid Chromatography. Ward’s hierarchical cluster analysis was applied for categorizing produce samples with regard to their nitrate content. Additionally, to account for the sanitation hazards associated with groundwater quality for drinking purposes, total coliform and turbidity were also assessed using the membrane filter (MF) technique and a nephelometer, respectively. Nitrate concentrations exceeded the prescribed permissible limits in 42% of the groundwater wells. The outcomes also exhibit significantly higher nitrate accumulation levels in root-tuber vegetables and leafy vegetables compared to fruit vegetables and fruits. Using cluster analysis, the accumulation of nitrate in vegetables and fruits was categorized into four clusters, specifying that radish contributes to 65.8% of the total content of nitrate in all samples. The Estimated Daily Intake (EDI) of nitrate and Health Risk Index (HRI) associated with consumption of groundwater exceeded the prescribed limit for the children’s target group in Mashhad’s south and central parts. Likewise, EDI and HRI values for produce consumption, in most samples, were found to be in the tolerable range, except for radish, lettuce, and cabbage, potentially posing risks for both children and adult consumers. The total coliforms in groundwater were found to violate the prescribed limit at 78.93% of the sampling locations and were generally much higher over the city’s central and southern areas. A relatively strong correlation (R2 = 0.6307) between total coliform and nitrate concentrations suggests the release of anthropogenic pollution (i.e., sewage and manure) in the central and southern Mashhad.

Nutrition Professionals’ Knowledge Towards Dietary Nitrate in Jeddah, Saudi Arabia: A Cross-Sectional Study

ObjectivesDietary nitrate (NO3) plays an important role in human's physiological processes. Nutrition professionals (NPs) have a crucial role in increasing the awareness of NO3 benefits across various health and academic settings. The aim of this study was to assess the level of knowledge towards the NO3 effects among NPs in Jeddah, Saudi Arabia based on their qualifications and years of experience.MethodsA cross-sectional study was conducted among NPs graduated or working in Clinical Nutrition Departments of health centers and two universities. A validated online questionnaire with a total of 12 questions assessed the dietary nitrate's knowledge with regards to its health effects, dietary sources, recommendations, biomarkers of intake, and metabolism. A Nitrate Knowledge Index (NKI) score (out of 23 points) was used to evaluate the responses.ResultsA total of 89 female NPs out of 144 successfully completed the questionnaire. Most of them aged ≤30 years (73%), possessed undergraduate degree (BS) (70.8%), and had an experience of ≤3 years of experience (73%). Overall, poor knowledge score was observed among NPs in most questions as the median was 10 (7) out of 23. The majority (64%) perceived the NO3 as beneficial. However, the most did not know its benefits in lowering the blood pressure (68.5%) and were unsure about the nitrate effects on cognitive function (60.7%), kidney function (57.3%) and cancer risk (48.3%) as well as the acceptable daily intake of nitrate (67.4%). Almost half of the NPs had insufficient knowledge of NO3 sources as they incorrectly identified bacon and sausage as high NO3 food. They also were unsure about the mechanisms involved in the conversion of nitrate into nitrite in the mouth (48.3%). Knowledge of factors that affect food NO3 content were generally good. No significant differences, (P > 0.05), were observed in the median scores of NKI among the participants based on their level of education (BS: 8(6) vs. graduate degrees 10 (8.25)), nor based on years of experience (Experience ≤ 3 years: 10 (7) vs. >3 years: 8.5 (6)).ConclusionsThe authors recommend developing and implementing educational programs to enhance the knowledge and beliefs towards NO3 among NPs, who work in clinical and academic settings.Funding SourcesKing Saud bin Abdulaziz University for Health Sciences.

Accumulation and human health risk assessment of nitrate in vegetables irrigated with different irrigation water sources- transfer evaluation of nitrate from soil to vegetables

The present study aimed to investigate the rate of accumulation, human health risk assessment, and nitrate-related transfer factor in vegetables irrigated with different sources, including treated wastewater effluent (TWE) of Kermanshah wastewater treatment plant, Gharasoo river water (RW) of Kermanshah, and well water with chemical fertilizer (WWF). For this purpose, three different types of vegetables, including basil, coriander, and radish, was cultivated, and each of them was irrigated by the three irrigation sources mentioned above. Finally, the amount of nitrate in different sources of irrigation, soil (before growing vegetables and after harvesting vegetables), and the mentioned vegetables was measured. Based on the study results, it can be concluded that the water of the Gharasoo River (RW), compared to the other two irrigation sources, causes more nitrate accumulation in the soil and vegetables grown in it. The highest transmission factor was related to basil vegetables irrigated with WWF. The results showed that the average daily intake of nitrate through the consumption of vegetables grown in Kermanshah with any irrigation water is less than the allowable amount, so the consumption of such vegetables is not dangerous to consumers' health. Therefore, it is suggested that the best irrigation source for vegetable cultivation in Kermanshah is TWE, provided that all of its physical, chemical and microbial parameters meet the standards for reuse in agriculture irrigation. Thus, the use of treated wastewater reduces the need for farmers to use chemical and organic fertilizers and cost-effectiveness, high frequency, and high availability.

Health Risk Assessment for Exposure to Nitrate in Drinking Water in Central Java, Indonesia.

Since 2005, over 30 epidemiological studies have evaluated the association between nitrate in drinking water and adverse health outcomes. Conditions that lead to nitrate pollution in water, such as open defecation, the proximity of septic tanks to water sources, and the use of inorganic fertilizer, are rampant in Indonesia, which has experienced little research evaluating nitrate in drinking water. We conducted a health risk assessment for exposure to nitrate in drinking water and evaluated the nitrate concentration in key water sources in two villages of rural Central Java, Indonesia. The nitrate concentrations in the drinking water ranged from 3.55 mg/L to 26.75 mg/L as NO3−. Daily nitrate intake estimates, calculated at 50% and 95% exposure to the maximum nitrate concentration of the drinking water in both villages, were above the levels associated with birth defects, colorectal cancer, and thyroid conditions observed in other studies. There was a large variation in nitrate concentrations between and within the villages at different water sources. Further research into whether these health outcomes exist in rural Central Java, Indonesia will be required to better understand this risk.

Daily intake of nitrate and nitrite via meat and poultry in Egypt

ABSTRACT Nitrate and nitrite are the most applied food additives to inhibit microbial growth. The main risk of nitrate and nitrite presence in food is the formation of nitrosamines during food preparation and digestion. However, dietary intake of nitrite and nitrate from food has potential cardiovascular benefits. Accordingly, 160 samples from meat and poultry were randomly collected to evaluate the level of occurrence nitrate and nitrite using an HPLC method and estimate the daily intake (EDI) of Egyptian adults and children. The levels of nitrate and nitrite ranged between 1.3–557 mg/kg and 6–812 mg/kg, respectively. The EDI was compared with the accepted daily intake (ADI) represented in the hazard index (HI) scale. The nitrite results clarify that all HI values were above 1 for all commodities, while for nitrate it exceeded 1 only for canned meat and basturma, when consumed by children.

Health risk assessment based on nitrate levels in ground and surface waters in different sites of the Elazığ Province, Turkey

Amaç: Bu çalışmada, Elazığ ilinin 65 farklı yerinden alınan yeraltı ve yerüstü su örneklerindeki nitrat konsantrasyonunun, bu bölgelerde yaşayan insanlar için olası sağlık tehlikelerinin araştırılması amaçlanmıştır. Yöntem: Kesitsel bir araştırma olan bu çalışmada, içme suyundaki nitrat düzeylerine spektrofotometrik olarak bakılmış olup içme suyu yoluyla yüksek nitrat alımının, yetişkinler, çocuklar ve bebekler üzerindeki olası sağlık risk değerlendirmesi, USEPA sağlık tehlike modeli (HQ) kullanılarak yapılmıştır. Bulgular: Su numunelerinin nitrat seviyeleri ortalaması 8.99±16.77 mg/L olarak hesaplanmıştır. Örnekleme noktalarının %6'sında Türk standartlarında (50 mg/L) ve Dünya Sağlık Örgütü (50 mg/L) standartlarında önerilen sınır değerlerden daha yüksek konsantrasyonlara sahip olduğu ortaya çıkmıştır. Nitratın, kronik günlük alımı (CDI), yetişkinler, çocuklar ve bebekler için sırasıyla 0.25±0.47, 0.67±1.25 ve 0.71±1.34 mg/kg/gün’dür. Tehlike katsayısı (HQ) değeri yetişkinler için 0.16±0.29, çocuklar için 0.42±0.78 ve bebekler için 0.44±0.83 olarak hesaplanmıştır. Sonuç: Tehlike katsayısı (HQ) değerleri, Elazığ ilinin %9.30’u yetişkin, %18.60’ı çocuk ve %20.93’ü bebek nüfusunun aşırı nitrat kullanımı nedeniyle kronik toksisite riski altında olduğunu göstermektedir. Bu nedenle, nitrat değerinin yüksek olduğu yerlerde su kaynaklarını korumak için gerekli tüm çevresel güvenlik önlemleri alınmalıdır.

Ingested Nitrate and Nitrite and Bladder Cancer in Northern New England.

N-nitroso compounds are hypothesized human bladder carcinogens. We investigated ingestion of N-nitroso compound precursors nitrate and nitrite from drinking water and diet and bladder cancer in the New England Bladder Cancer Study. Using historical nitrate measurements for public water supplies and measured and modeled values for private wells, as well as self-reported water intake, we estimated average nitrate concentrations (mg/L NO3-N) and average daily nitrate intake (mg/d) from 1970 to diagnosis/reference date (987 cases and 1,180 controls). We estimated overall and source-specific dietary nitrate and nitrite intakes using a food frequency questionnaire (1,037 cases and 1,225 controls). We used unconditional logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI). We evaluated interactions with factors that may affect N-nitroso compound formation (i.e., red meat, vitamin C, smoking), and with water intake. Average drinking water nitrate concentration above the 95th percentile (>2.07 mg/L) compared with the lowest quartile (≤0.21 mg/L) was associated with bladder cancer (OR = 1.5, 95% CI = 0.97, 2.3; P trend = 0.01); the association was similar for average daily drinking water nitrate intake. We observed positive associations for dietary nitrate and nitrite intakes from processed meat (highest versus lowest quintile OR for nitrate = 1.4, 95% CI = 1.0, 2.0; P trend = 0.04; OR for nitrite = 1.5, 95% CI = 1.0, 2.1; P trend = 0.04, respectively), but not other dietary sources. We observed positive interactions between drinking water nitrate and red meat (P-interaction 0.05) and processed red meat (0.07). Our results suggest the importance of both drinking water and dietary nitrate sources as risk factors for bladder cancer.

Association of daily nitrate consumption with blood pressure and other risk factors for cardiovascular diseases in a representative UK population

AbstractDietary inorganic nitrate has been shown to lower blood pressure (BP) and improve endothelial function(1). The main sources of dietary nitrate are vegetables (root and green leafy varieties) as well as drinking water but data available on dietary analysis software on nitrate levels in vegetables and vegetable-based foods is very limited. To date, very few studies have investigated the relationship between the level of consumption of dietary nitrate on BP and other cardiovascular disease (CVD) risk factors in a representative UK population. The aim of the study was to address this knowledge gap using data from the National Diet and Nutrition Survey (NDNS) years 1–8, a cross-sectional study conducted in 3339 men and women aged 19–64 y between 2008/09–2011/12. A comprehensive database was first developed to evaluate the nitrate and nitrite levels in vegetables, cured meats and composite dishes to more accurately estimate the dietary nitrate intakes of the NDNS participants. The population was then classified into quartiles of daily nitrate intake, with quartile 1 (Q1: 26–106 mg/d) and quartile 4 (Q4: 183–559 mg/d) representing diets with the lowest and highest intakes, respectively. ANCOVA analysis was performed to determine the relationship between the level of daily nitrate intake with available data on biomarkers of CVD risk (including BP (systolic, diastolic and pulse pressure), lipid profile, (total, high-density lipoprotein and low-density lipoprotein (LDL-C) cholesterol), C-reactive protein, anthropometric measures (body mass index and waist to hip ratio) and glycaemic control (glucose and glycated haemoglobin). There were significant differences in systolic (P-trend = 0.008) and diastolic (P-trend = 0.025) BP across increasing quartiles of dietary nitrate intake, with BP significantly lower in Q3 than all other quartiles. Pulse pressure (calculated as systolic–diastolic BP) was also found to be significantly different across quartiles (P-trend = 0.001), with diets of participants in Q3 and Q4 being associated with significantly lower pulse pressures than those in Q1 (P-Q1 vs. Q3 = 0.005, P-Q1 vs. Q4 = 0.007). All of the other CVD risk markers were not different between quartile groups. Our preliminary results suggest that the level of dietary nitrate intake may be significantly associated with BP, a key independent CVD risk factor. There is an urgent need to more accurately estimate the dietary nitrate intake in the UK population and to determine whether the source of dietary nitrate (vegetables vs cured meats) impacts on the significant relationship with BP.

Ingested nitrate and nitrite and bladder cancer in Northern New England

OPS 36: Health effects of dietary exposures, Room 210, Floor 2, August 27, 2019, 4:30 PM - 5:30 PM Background/Aim: N-nitroso compounds (NOCs) are hypothesized human bladder carcinogens. Nitrate and nitrite are NOC precursors; sources include contaminated drinking water and diet. We examined nitrate and nitrite ingestion and bladder cancer risk in the New England Bladder Cancer Study, a population-based case-control study in Maine, New Hampshire, and Vermont. Methods: Using historical nitrate measurements for public water supplies, measured and modeled values for private wells and self-reported water intake, we estimated average nitrate concentrations (NO3-N mg/L) and average daily nitrate intake (mg/day) from 1970 to diagnosis/reference date for 987 cases and 1180 controls. We also estimated source-specific (animal, plant, processed meat) dietary nitrate and nitrite intakes using a food frequency questionnaire (1037 cases and 1225 controls). We used unconditional logistic regression to estimate odds ratios (OR) and 95% confidence intervals (CI) adjusting for age, gender, smoking, disinfection by-products, and other factors. We evaluated interactions with factors affecting NOC formation (i.e., red and processed meat, vitamin C, smoking). Results: Average drinking water nitrate concentration above the 95th percentile (>2.07 mg/L) compared with the lowest quartile (<=0.21 mg/L) was associated with bladder cancer risk (OR=1.50, CI: 0.97-2.32; p-trend=0.01); the association was similar for average drinking water nitrate intake. We observed positive associations for dietary nitrate and nitrite intakes from processed meat (highest vs. lowest quintile OR=1.42, CI: 1.01-1.98; p-trend=0.04; OR=1.48, CI: 1.04-2.09; p-trend=0.04, respectively), but no trends for other sources. Risk was highest among those with >2.07 mg/L NO3-N and >median red or processed meat intake vs <0.21 mg/L NO3-N/< median intakes (OR=2.61, CI: 1.33-5.11 and OR=3.47 CI: 1.75-6.87; p-interaction=0.05 and 0.07, respectively). We observed no interaction with vitamin C or smoking. Conclusions: Our results suggest the importance of both drinking water and dietary nitrate sources as risk factors for bladder cancer especially among those with high red or processed meat intake

Monitoring and exposure assessment of nitrate intake via fruits and vegetables in high and low risk areas for gastric cancer.

Gastric cancer (GC) is the first leading cause of cancer-related deaths in Iran. GC is a multifactorial disease and is caused by the interaction of genetic and environmental factors. The aim of this study was to assess the exposure and risk of nitrate intake through fruits and vegetables (F&V) in high-risk area (HRA) and low-risk area (LRA) of GC in Iran. Twenty nine species of F&V were examined for nitrate by reverse-phase HPLC (RP-HPLC) method. Food frequency questionnaire (FFQ) data of 2000 adults participating in Persian cohort were applied to determine consumption patterns of F&V in those areas. A point-estimate daily intake was applied to compare two areas in terms of nitrate intake. Monte-Carlo simulation technique was applied to estimate chronic daily intake (CDI) of nitrate. The results showed that point-estimate daily intake of nitrate for subjects participated in the study was 2.02 ± 1.02mgkg-1day-1 in HRA and 1.98 ± 1.05mgkg-1day-1 in LRA. 6.53% of the participants in the HRA, and 5.9% of the participants in the LRA had an unacceptable point-estimate daily intake compared with an acceptable limit of 3.7mgkg-1day-1 established by FAO/WHO. CDI of nitrate in HRA was 1.94 ± 0.95mgkg-1day-1 and in the LRA was 1.93 ± 1.06mgkg-1day-1. The results showed that there is no difference between HRA and LRA in terms of nitrate intake through F&V.

Assessment of dietary nitrate intake in humans: a systematic review

The nitrate content of foods and water is highly variable, which has implications for the compilation of food-composition databases and assessment of dietary nitrate intake. A systematic review was conducted to ascertain the dietary assessment methods used and to provide estimates of daily nitrate intake in humans. Relevant articles were identified by a systematic search of 3 electronic databases (PubMed, Web of Science, and Embase) from inception until February 2018. Observational studies conducted in adult populations and reporting information on dietary assessment methods and daily nitrate intake were included. Ecological analyses were conducted to explore the association of nitrate intake with indexes of economic development [Gross Domestic Product (GDP) and KOF Index of Globalization]. A total of 55 articles were included. Forty-two studies investigated associations between nitrate intake and disease risk; 36 (87%) of these studies examined the association between nitrate intake and cancer risk, whereas only 6 studies explored the association of nitrate intake with the risk of diabetes, glaucoma, kidney failure, hypertension, and atherosclerotic vascular disease. The majority of studies used food-frequency questionnaires to assess nitrate intake (n=43). The median daily nitrate intakes in healthy and patient populations were 108 and 110 mg/d, respectively. We found a significant inverse correlation of nitrate intake with GDP (r=-0.46, P<0.001) and KOF index (r=-0.31, P=0.002). The median estimated daily nitrate intakes by healthy and patient populations were similar, and these values were below the safe upper intake of daily intake (3.7 mg nitrate ion/kg body weight). However, there is considerable heterogeneity in the application of food-composition tables, which may have implications for the accuracy of estimated daily nitrate intake. The association between nitrate intake and risk of cardiometabolic diseases needs further investigation. The protocol for this systematic review has been registered in the PROSPERO database (https://www.crd.york.ac.uk/prospero; CRD number: 42017060354).

Increasing vegetable intake to obtain the health promoting and ergogenic effects of dietary nitrate.

Increased consumption of dietary nitrate increases plasma nitrate and nitrite concentrations, and has been shown to elicit cardio-protective effects and improve exercise performance. Nitrate consumption in the habitual diet is mainly dependent on nitrate-rich vegetables, such as green leafy and root vegetables, with total vegetable consumption accounting for approximately 50-85% of our daily nitrate intake. Whereas 'supplementation' with dietary nitrate in research studies has mainly been accomplished through the use of (concentrated) nitrate-rich beetroot juice, dietary strategies focusing on increased intake of nitrate-rich vegetables may represent a similarly effective alternative for increasing dietary nitrate intake and, as such, obtaining the associated cardiovascular health and ergogenic benefits.

Inorganic nitrate alleviates the senescence-related decline in liver function.

Senescence-related decline in liver function is a common complication in the elderly that can lead to impaired health in older individuals. Dietary nitrate supplements have physiological and therapeutic effects on organ function by nitrate (NO3-)-nitrite (NO2-)-nitric oxide (NO) pathway. However, the role of dietary nitrate on the senescence-related decline in liver function is unclear. The findings of the present study showed that nitrate levels in the serum and liver decreased, whereas the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum increased in ageing mice. Consistently, cell senescence, decreased glycogen levels and increased lipid deposition were found in the liver of aged mice, both glucokinase (GCK) and phosphoenolpyruvate carboxykinase (PCK) were down-regulated (n=10). Daily nitrate intake (0.5 mmol L-1) restored nitrate levels, decreased ALT and AST levels, and prevented cell senescence and structural and glucose and lipid metabolism degeneration in liver tissue both in D-galactose (D-gal)-induced ageing mice (n=10) and in natural aged mice (n=10). In conclusion, the present study demonstrated that the reduction of nitrate levels was correlated with liver degeneration in ageing individuals and that dietary supplement of nitrate could restore the nitrate levels in serum and the liver and prevent ageing-related liver degeneration.

マーケットバスケット方式による日本人の硝酸・亜硝酸の一日摂取量調査研究(1995～1996年度)

マーケットバスケット方式による日本人の硝酸・亜硝酸の一日摂取量調査研究(1995～1996年度)

Nitrate in drinking water and vegetables: intake and risk assessment in rural and urban areas of Nagpur and Bhandara districts of India.

The study focuses on the estimation of health risk from nitrate present in the drinking water and vegetables in Nagpur and Bhandara districts in the state of Maharashtra, India. Drinking water samples from 77 locations from the rural as well as urban areas and 22 varieties of vegetable were collected and analyzed for the presence of nitrate for a period of 1year (two seasons). The daily intake of nitrate from these water and vegetable samples was then computed and compared with standard acceptable intake levels to assess the associated health risk. The mean nitrate concentration of 59 drinking water samples exceeded the Bureau of Indian Standards limit of 45mg/L in drinking water. The rural and urban areas were found to have mean nitrate concentration in drinking water as 45.69±2.08 and 22.53±1.97mg/L, respectively. The estimated daily intake of drinking water samples from 55 study sites had nitrate concentration far below the safety margin indicating serious health risk. The sanitation survey conducted in 12households reported contaminated source with positive E. coli count in 20 samples as the major factor of health risk. The average nitrate concentration was maximum in beetroot (1349.38mg/kg) followed by spinach (1288.75mg/kg) and amaranthus (1007.64mg/kg). Among the samples, four varieties of the vegetables exceeded the acceptable daily intake (ADI) with an assumption of 0.5kg consumption of vegetables for an average of a 60-kg individual. Therefore, irrigation of these locally grown vegetables should be monitored periodically for nitrogen accumulation by the crop above the ADI limit. The application of nitrogenous fertilizers should also be minimized in the rural areas to help protect the nitrate contamination in groundwater sources.

Risk assessment and monitoring programme of nitrates through vegetables in the Region of Valencia (Spain)

This study was carried out to determine current levels of nitrate in vegetables marketed in the Region of Valencia (Spain) and to estimate the toxicological risk associated with their intake. A total of 533 samples of seven vegetable species were studied. Nitrate levels were derived from the Valencia Region monitoring programme carried out from 2009 to 2013 and food consumption levels were taken from the first Valencia Food Consumption Survey, conducted in 2010. The exposure was estimated using a probabilistic approach and two scenarios were assumed for left-censored data: the lower-bound scenario, in which unquantified results (below the limit of quantification) were set to zero and the upper-bound scenario, in which unquantified results were set to the limit of quantification value. The exposure of the Valencia consumers to nitrate through the consumption of vegetable products appears to be relatively low. In the adult population (16–95 years) the P99.9 was 3.13 mg kg−1 body weight day−1 and 3.15 mg kg−1 body weight day−1 in the lower bound and upper bound scenario, respectively. On the other hand, for young people (6–15 years) the P99.9 of the exposure was 4.20 mg kg−1 body weight day−1 and 4.40 mg kg−1 body weight day−1 in the lower bound and upper bound scenario, respectively. The risk characterisation indicates that, under the upper bound scenario, 0.79% of adults and 1.39% of young people can exceed the Acceptable Daily Intake of nitrate. This percentage could join the vegetable extreme consumers (such as vegetarians) of vegetables. Overall, the estimated exposures to nitrate from vegetables are unlikely to result in appreciable health risks.