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N-nitrosamines are a class of carcinogenic chemical compound. Considering the large-scale application of agrochemicals globally, the elimination of N-nitrosamines from pesticides should be a priority for manufacturers and regulators. A set of methods was developed and validated for the determination of the toxicologically relevant N-nitrosamine impurity of ethalfluralin (ethyl-N-(2-methylallyl) N-nitroso amine—EMANA) in 33% wv−1 emulsifiable concentrate (EC) formulations. Solid Phase Extraction (SPE) was compared with the “dilute and shoot” approach. Gas chromatography (GC) was combined with Flame Ionization Detection (FID) and mass spectrometry (MS). For MS, two mass filtering modes (Selective Ion Monitoring—SIM, tandem mass spectrometry—MS/MS) and two ionization modes (Electron Ionization—EI, Positive chemical ionization—PCI) were applied. It was concluded that, in the case of samples with high nitrosamine concentration (>90 μg g−1), the “dilute and shoot” approach can be applied without compromising the quality of the results. SPE, however, is required to attain the LOQ (0.33 μg g−1) with good recovery (97.4–110.67%), linearity (R > 0.99) and precision (%RSD 0.68–1.74). The LOQ supersedes the limit set by EFSA (1 μg g−1) in the Technical Active Substance—TAS. The concentration range of the methods is 0.05–110 μg g−1. The methods were applied for the official surveillance program of the Greek agrochemicals market.

Introduction. The increasing global consumption of processed meat products has led to certain concerns. For instance, processed meat products are known to contain carcinogen precursor compounds, thus creating the risk of chronic diseases. The present study was performed to estimate the food safety status of processed meat products available in Iran and evaluate the related effective factors. Study objects and methods. 140 samples of seven most popular commercial types of cooked sausages were obtained from four major meat factories (A, B, C and D) in 140 samples were collected from seven most popular commercial types of cooked sausages as follows: beef salami 90%, chicken salami 90%, dry cured sausage 70%, dry cured salami 60%, beef sausages 55%, chicken sausages 55% and Frankfurt sausage 40% (n = 5) from four major meat factories (A, B, C and D) in Tehran. The samples were screened for residual nitrite, ascorbic acid, and nitrosamine contents on days 0, 7, 14, 21, and 28. The results indicated that products from meat factory B had lower residual nitrite content in the samples with high content of meat. Beef salami (90% of meat) and Frankfurt sausage (40% of meat) contained the lowest and highest amounts of residual nitrite on day 0 – 73.99 and 177.42 mg of nitrite per 1 kg of meat, respectively. Results and discussion. Beef salami contained 90% of meat, chicken salami – 90%, dry cured sausage –70%, dry cured salami – 60%, beef sausages – 55%, chicken sausages – 55%, and Frankfurt sausage – 40% (n = 5). Nitrite reduction rates in sausages with a smaller diameter, e.g. Frankfurt sausage, were significantly lower (P < 0.05), compared to salami samples. The difference can be explained by the shorter cooking time. Nitrosamine formation increased during refrigerated storage; however, it was not significant in all samples. During refrigerated storage, nitrosamine formation depended on the level of added nitrite, the amount of residual nitrite, ascorbic acid, pH, and cooking temperature. Ascorbic acid content decreased significantly (P < 0.05) during refrigerated storage. Conclusion. The findings demonstrate significant correlation between the meat content, cooking time, nitrite content, and nitrosamine formation.

This study aims to determine the amounts of seven volatile N-nitrosamine (VNA) derivatives which are in the risk group, in processed sausages. It also aimed to investigate the effects of the amount of added ascorbic acid, on the VNA level during the sausage manufacturing processes. For this purpose, meat doughs were prepared with two different levels of ascorbic acid. These meat doughs were put into the production process and packaged in two different packages. Thus, VNA derivatives and their amounts were determined according to production stages (heat treatments), packaging method (vacuum, MAP), storage process (Day 1, 7, 15, 30, 60, 90). As a result, it was found that the sausage product carries risk of VNA formation from the beginning of its production until the last day of storage before consumption for up to 90 days.

The effects of different nitrite levels (50, 100, and 150 mg/kg meat) and dry-frying temperatures (100, 150, 200 and 250 °C) on the moisture movement, colour, sensory variables and residual nitrite and N-nitrosamine levels in smoked bacon were investigated. Increasing the dry-frying temperatures significantly increased the cooking loss and decreased the moisture content (P 0.05). The bacon L*-values showed an increasing trend at first and then decreased, with the highest value of the bacon with 150 mg/kg nitrite was obtained at 100 °C and 150 °C. In addition, a*-values were significantly affected by the nitrite level and dry-frying temperature (P 0.05), with the highest value of the bacon samples with 100 and 150 mg/kg nitrite observed at 250 °C. The residual nitrite content level initially increased (from unheated control to 150 °C) and then decreased (from 150 to 250 °C) sharply with increasing dry-frying temperatures in the bacon samples with the same sodium nitrite levels. N-methyl-N-nitrosoaniline (NMPhA) and N-nitrosomorpholine (NMOR) were measured in a number of smoked bacon samples, and a significant positive correlation (R

The present study investigated the protective effects of the polyphenol epicatechin on the protein structural changes, gel properties and N-nitrosodiethylamine (NDEA) formation of oxidatively stressed myofibrillar protein (MP). Results showed that oxidation treatments to MP significantly increased their carbonyl content and surface hydrophobicity as compared to the control groups (p

Several experiments were completed to further evaluate use of α-tocopherol-coated salts as inhibitors of N-nitrosamine formation in fried bacon. Studies with dry-cured bacon prepared with various levels of α-tocopherol indicated that the chemical did not contribute to formation of N-nitrosodimethylamine (NDMA). N-Nitrosopyrrolidine levels for the α-tocopherol-treated bacon samples were generally below 5 μg/kg, which represents an average reduction of approximately 70%. Experiments were also done to evaluate the role of lecithin as a possible precursor of NDMA in brine-cured bacon. At concentrations used to disperse α-tocopherol in the curing brine, lecithin did not contribute to NDMA formation in bacon prepared with α-tocopherol-coated salts.

High nitrate and amine-rich food intake may result in an increased risk of endogenous formation of carcinogenic N-nitroso compounds (NOCs). We studied the effects of whole strawberries, garlic and kale on the formation of N-nitrosodimethylamine (NDMA) in a traditional Korean diet (amine and nitrate-rich) in simulated saliva and gastric conditions. The addition of whole strawberries, kale and garlic juices in the diet reduced NDMA formation by amine and nitrate. Strawberries and garlic juice were more effective than kale. To identify active compound, isolated fractions were prepared from strawberries or garlic juice samples by preparative liquid chromatography. Inhibition of NDMA formation and nitrite-scavenging ability of each fraction (strawberries: S1–S4; garlic juice: A1–A5) was tested. Fraction A4 inhibited NDMA formation by 50.5 ± 5.4% and increased the effect of nitrite-scavenging by 72.3 ± 8.7%. Fractions A3 and A4 were identified as 1,2-benzendicarboxy acid (A3) and S-oxodially disulfide (A4) compounds by mass spectrophotometry and 13C nuclear magnetic resonance.

Background Nitrosamine is amongst carcinogen chemical compounds, which can enter the human body through consumption of food. Potatoes are a root vegetable consumed by many people around the world, however their potential for nitrosamine formation during cooking processes needs to be considered for public health matters. Objectives In this study we evaluated the effect of conventional potato cooking method on N-nitrosamine compound formation. Materials and Methods The amounts of four nitrosamines, namely N-nitrosodimethylamine (NDMA), N-nitrosodiethylamine (NDEA), N-nitrosopiperidine (NPIP) and N-nitrosopyrrolidine (NPYR) were determined in four different potato-baking methods. Sixty potato samples were randomly collected from Hamadan city. Fried potato samples were roasted at 180°C and boiled potato samples were scalded at 120°C. Nitrosamine levels were measured using gas chromatography coupled with electronic ionization detector (GC-EID), and spectrophotometry was used for measuring nitrite. Results Fried samples that were measured by the gas chromatography method had the highest average levels of nitrosamine compounds; NDMA, 5.09 ng kg-1, and NDEA, 8.66 ng kg-1. Low levels of nitrosamine compounds were associated with raw potatoes, in which no nitrosamine compound was detected. Based on the analysis of the potato samples by spectrophotometry, the highest levels of nitrite was found in raw potatoes with a mean of 2.43 mg kg-1 and the lowest levels of nitrite were detected in boiled potatoes with an average of 1.172 mg kg-1. Conclusions Nitrosamine was formed with conventional potato baking methods with the most nitrosamine formation found on the surface fried samples. Nitrites amount in baked potatoes decreased. Generally, the amount of nitrosamine in baked potato samples was lower than acceptable limits.

Salted and fermented anchovy sauce spiked with or without N -nitrosodimethylamine (NDMA) and N -nitrosopyrrolidine (NPYR) was irradiated at 0, 5, 10, 15 and 20 kGy. NDMA and NPYR reduction by irradiation was not observed in non-spiked samples at 0 week, while a significant reduction was observed after 4 weeks of storage at 15 °C ( P N -nitrosamine spiked samples, a positive effect of irradiation on NDMA and NPYR reduction was observed. NDMA and NPYR levels were decreased by irradiation at 5 kGy or above after storage. Therefore, gamma irradiation has a possibility to reduce N -nitrosamines in salted and fermented anchovy sauce.

In order to provide data on N-nitrosamine (NA) and sanitation in fish available in domestic markets, this study analyzed the levels of NA and its precursors in 9 samples of sea breams and yellow croakers, 12 samples of red-flesh fish, 38 samples of white fish, 5 samples of Alaska pollacks and cod, and 8 species of imported fish. Sea breams and yellow croakers had nitrite concentrations ranging from non-detectable (ND) to 7.4 mg/kg, red fish ND to 5.3 mg/kg, white fish ND to 18.7 mg/kg, Alaska pollacks 0.3 to 2.2 mg/kg, and imported fish from 0.4 to 12.8 mg/kg. Nitrates in sea breams and yellow croakers ranged from 1.2 to 41.19 mg/kg, red fish 0.6 to 26.1 mg/kg, white fish 4.3 to 75.9 mg/kg, Alaska pollacks 0.4 to 3.1 mg/kg, and imported fish ND to 16.0 mg/kg. DMA concentrations were 69.8 to 219.9 mg/100 g in sea breams and yellow croakers, 4.1 to 336.3 mg/100 g in red fish, 1.3 to 331.9 mg/100 g in white fish, 15.7 to 312.3 mg/100 g in Alaska pollacks, and 1.0 to 71.8 mg/100 g in imported fish. TMA concentrations in sea breams and yellow croakers, red fish, white fish, Alaska pollacks and imported fish were 43.8～496.2, 12.3～127.0, 2.0～525.9, 15.4～122.4, and 4～70.6 mg/100 g, respectively. For NA in fish distributed in local markets, only N-nitrosodimethylamine (NDMA) was detected, and its concentrations ranged from 4.7 to 73.7 ㎍/kg in sea breams and yellow croakers, 2.2 to 56.5 ㎍/kg in red fish, ND to 143 ㎍/kg in white fish, 3.8 to 33.3 ㎍/kg in Alaska pollacks, and 2.1 to 102.2 ㎍/kg in imported fish.

The influence of biogenic amines (i.e. putrescine, cadaverine, spermidine and spermine) on the N-nitrosamine formation in heated cured lean meat was studied in the presence or absence of sodium nitrite and at different meat processing temperatures. Experimental evidence was produced using gas chromatography with thermal energy analysis detection (GC-TEA). Concentration of N-nitrosamines was modelled as a function of the temperature and the nitrite concentration for two situations, i.e. presence or absence of added biogenic amines to the meat. The significance of the influence of the changing parameters was evaluated by ANOVA (Analysis of Variance). It was found that higher processing temperatures and higher added amounts of sodium nitrite increase the yields of N-nitrosodimethylamine (NDMA) and N-nitrosopiperidine (NPIP). Spermidine and putrescine amplify the formation of NDMA, but spermine and cadeverine do not influence the formation of this N-nitrosamine. Spermidine and cadeverine cause a significant increase of NPIP. Beside N-nitrosopyrrolidine (NPYR) in some rare cases, no other volatile N-nitrosamines are detected.

Studies were conducted to determine the feasibility of using Atlantic menhaden mince and surimi as partial meat substitutes for red meats in the formulation of frankfurters. The effects of the following factors on methylamine and volatile nitrosamine content in broiled frankfurters substituted with the menhaden were evaluated: fish form (washed and unwashed mince and surimi), percent substitution (15 and 50%), storage of fresh and frozen fish preprocessing (0-6 months), and refrigerated storage of frankfurters postprocessing (0-56 days). The overall results of these studies indicate that only trace levels of N-nitrosodimethylamine, the only volatile nitrosamine detected, were found in these frankfurters

N-Nitrosamines are formed in a multi-step reaction of nitrite with free amino acids and amines in the meat products. The aim of this study was to determine the role of proline and hydroxyproline in N-nitrosamines formation during heating of cured meat. A lean meat model was used with different nitrite concentrations (0, 120, and 480mg/kg), and addition of proline and hydroxyproline (1000mg/kg), followed by heating at different temperatures. Volatile nitrosamines were analyzed with GC-TEA. The nitrosamine content never exceeded 10μg/kg and stayedLOQ as long as the nitrite level of 120mg/kg was not surpassed. The importance of proline as a precursor for N-nitrosamine formation was confirmed. In contrast, hydroxyproline inhibited NPYR formation (N-nitrosopyrrolidine) because no traces were found after addition of hydroxyproline. NPYR formation was not related to nitrite, but was significantly influenced by temperature (⩾200°C) and proline. NDMA-presence (N-nitrosodimethylamine) in heated meat products was influenced by nitrite and temperatures120°C.

Residual nitrite and N-nitrosamine levels were monitored on irradiated emulsion-type cooked pork sausage in aerobic or vacuum packaging states during storage. The sausage was irradiated at 0, 5, 10, and 20 kGy and stored at 4 degrees C for 4 weeks. The residual nitrite levels were significantly reduced by gamma irradiation (P < 0.05), whereas the vacuum packaging was more effective for nitrite reduction than aerobic packaging during storage. N-nitrosodimethylamine (NDMA) and N-nitrosopyrrolidine (NPYR) levels were significantly reduced in the vacuum packaged sausage irradiated with 20 kGy after 4 weeks. Reduction of NPYR in aerobically packaged sausage was also found after 4 weeks by irradiating with a 5-kGy or higher dose. NDMA reduction was shown in vacuum packaging and irradiation at 20 kGy. Gamma irradiation was effective in reducing the residual nitrite all throughout storage and N-nitrosamines in sausage after storage.

A survey of Polish malt and beer for volatile N-nitrosamines has been conducted. N-Nitrosodimethylamine was found in malt at levels ranging from 0.2 to 3.6 micrograms/kg (average 1.5 micrograms/kg) and in beer at levels up to 0.3 microgram/kg (average 0.2 micrograms/kg). The use of indirect malt dryers is credited with the low levels of N-nitrosamines found.

The effects of competitive nitrosation by ascorbic acid and sorbic acid on N-nitrosamine formation were studied in a heterogeneous protein-based model system containing a 20% non-aqueous phase. The reactions were examined at 37°C with an aqueous phase pH of 5.25. Under certain conditions ascorbic acid enhanced the nitrosation of secondary amines. The overall extent to which ascorbic acid affected N-nitrosation was found to depend on the time-scale of the reaction and also the phase in which N-nitrosamine formation occurred. Sorbic acid reduced N-nitrosation in both phases of the heterogeneous system.

The reactions of sodium nitrite, S-nitrosocysteine hydrochloride, S-nitrosoglutathione and a ‘protein-bound nitrite’ model system with N-methylaniline at pH 5.5 and 37°C have been compared. The results show that the rate of nitrosamine formation from sodium nitrite and S-nitrosocysteine is greater than that from the model system although the latter depends upon the local concentration of nitrosothiol groups on the matrix. Transnitrosation by S-nitrosoglutathione is considerably slower than the other reactions. The implications of the results with respect to nitrosamine formation in cured meat are discussed.

The chemical interaction of lipids and lipid-containing foods with nitrite in a mild acidic aqueous system was investigated. Methyl linoleate-coated silica gel, Intralipid, cow's milk, mayonnaise, yolk and miso reduced a considerable amount of nitrite. Methyl linoleate-coated silica gel and cow's milk extensively prevented the formation of carcinogenic N-nitrosamines. It seemed likely that the unsaturated fatty acid residues were responsible for the interaction of lipids with nitrite. Methyl linoleate was changed into two or more unidentified products, neither of which was the hydroperoxides of the ester.

The nitrosamine content of 16 New Zealand beers and one Australian beer, all manufactured in 1980, was determined by chemiluminescence. The levels, calculated as N-nitrosodimethylamine (NDMA) ranged from 0.2–1.8 μg dm−3 with a mean of 0.76 μg dm−3. Over a period of 2 years, the NDMA levels in New Zealand malt have been reduced as the result of changes in kilning technology, introduced to control the level of nitrogen oxides in kiln air. For example, the mean value for directly-fired malt was 5.4 μg kg−1, that for malt dried in air heated by burners to which sulphur had been added was 2.4 μg kg−1 and that for malt dried in air to which SO2 had been released was 0.3 μg kg−1. For the purposes of quality control, screening beer or malt for nitrosamines can be accomplished adequately by the injection of CH2Cl2 extracts directly into a thermal energy analyser.

Since certain N-nitrosamines are highly carcinogenic, formation and isolation of these compounds from food systems has received much attention in the past decade. This paper reviews the N-nitrosamine literature of the past 3 years, especially as it relates to cured meat products. This review examines occurrence of nitrites and amines in food systems, presence of N-nitrosamines in bacon, and also means of minimizing formation of these compounds. In addition, regulatory changes pertaining to nitrite usage in curing procedures as well as some areas of future research are discussed.

Solutes commonly employed in curing solutions were evaluated for their effect on nitrosamine formation utilizing a ground pork model system. Sodium erythorbate and sodium ascorbate were found to be equally effective in reducing nitrosopyrrolidine levels. The incorporation of sodium tripolyphosphate or sucrose had no detectable effect on nitrosamine formation. However, sodium chloride, the solute present at the highest concentration in bacon curing solutions, exhibited a concentration dependent inhibition of nitrosopyrrolidine formation. Nitrosopyrrolidine levels in samples containing no added sodium chloride were found to be 50% higher than samples processed with 1.5% added salt.

A model bacon system has been developed which enables a more reproducible determination of N-nitrosamines when compared to conventional methods of bacon production. Utilizing this system, the effect of slice thickness and frying time on nitrosopyrrolidine (NPyr) formation has been demonstrated. Short frying periods (3 min/side) result in higher NPyr levels for thinner sliced samples and longer frying periods (5 min/side) result in higher NPyr levels for thicker sliced samples. The level of N-nitrosamine formed is integrally related to slice thickness and frying time and may be explained when two factors are considered, the rate of N-nitrosamine formation and the rate of its volatilization.

Thirty-nine fried bacon samples and corresponding fried-out fats were collected from randomly selected consumers' homes. Bacons were purchased and cooked in the course of preparing meals containing bacon. The average volatile N-nitrosamine content μg/kg) of the rasher and fried-out fat, respectively, were: N-nitrosodimethylamine, 4.0 and 5.3; N-nitrosopiperidine, 0.7 and 1.5; N-nitrosopyrrolidine, 17 and 32; N-nitrosothiazolidine, 8.9 and 3.4. The average daily ingestion of N-nitrosopyrrolidine from bacon for our survey respondents was estimated to be 76 ng/person/day. A majority of respondents indicated that they used the fried-out fat as a cooking oil.

A model ionic N-nitrosamine (N-nitroso-N1N1-dimethylpiperazinium iodide) was synthesised in order to develop an appropriate analytical method for examining the possible incidence of this class of compounds in food. A procedure suitable for its analysis in biological samples is described and is based on preparation of an aqueous extract, ion-pair extraction into an organic solvent, separation by high-performance liquid chromatography and detection with a thermal-energy analyzer. The average recovery of the ionic N-nitrosamine from cured meat was 83% at 200 μg/kg; the detection limit was 50 gm/kg. bei den Muskelproben nahezu 30% der mit Hilfe der

It has been well established that human foods may contain trace amounts of carcinogenic N-nitrosamines. Originally, it was thought that the use of nitrite as a curing agent for flesh foods was the major source of these trace compounds in the diet. Subsequent research has clearly shown that other processing and packaging procedures can also introduce trace amounts of these carcinogens into foods. These procedures include drying foods in direct flame heated air, migration from food contact surfaces and direct addition as contaminants. In addition, other reports of N-nitrosamines in foods have less well defined routes of contamination. These sources of N-nitrosamines in foods will each be briefly reviewed in this paper and recent data from our laboratory concerning N-nitrosamines in products which directly contact foods presented. We also are reporting the N-nitrosothiazolidine content of fried-out bacon fat.

Soya products such as Tofu (soya-bean curd), soya milk, Miso (soya-bean paste) and Bonlact (powdered soya milk with additives) are very common foods commercially available in Japan. The effects of these soya products on nitrite concentration and on the formation of N-nitrosamines in vitro were investigated. All of these soya products effectively decreased nitrite levels at pH 3 and 4, the effect being greater at pH 3. The soya products inhibited the formation of N-nitrosodimethylamine and N-nitrosodiethylamine from sodium nitrite and the appropriate dialkylamine at gastric pH. For example, 20% (w/v) Tofu, 60% (v/v) soya milk, 10% (w/v) Miso and 4% (w/v) Bonlact inhibited by 46, 51, 74 and 44%, respectively, the formation of N-nitrosodimethylamine from 0·2 m -nitrite and 0·05 m -dimethylamine at pH 3 and 37°C for 3 hr. The loss of nitrite and inhibition of N-nitrosamine formation by soya products may be attributed to the lipids or to the minor phenolics contained in the products.

Two samples, one beer and one malt, have been distributed to 55 laboratories in 15 countries, to be analysed for N‐nitrosodimethylamine (NDMA) N‐nitrosopyrollidine (NPYR) and N‐nitrosoproline (NPRO) by the method of their choice. Results received from 35 laboratories demonstrated that at the low levels of contamination which may be encountered at present for NDMA in beer and malt, generally reliable data can be obtained in malt, but in beer, 20% of the results were discarded as outliers by the statistical test results. More variability was encountered for the analysis of NPYR. Only a limited number of results were provided for NPRO, which also showed greater variability.