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Liquid chromatography-tandem mass spectroscopy (LC-MS/MS) is an accurate and specific technique for drug residue analysis in different matrices. The high specificity and sensitivity of the multiple reaction monitoring (MRM) approach for detecting drugs such as aldehydes, which have the potential to change mass during the sample preparation phase, becomes a drawback during the analysis process. In this study, concerns about the intrusion of solvent molecules into spiramycin's chemical structure as an aldehydic drug as well as the stability of spiramycin in the milk matrix were addressed. Furthermore, the binding sites where the solvent molecules could bind to spiramycin molecules were investigated through nuclear magnetic resonance (NMR) spectroscopy. It was revealed that water, ethanol, and methanol as protic solvents can add to the formyl group of spiramycin molecules during standard solutions preparation while there was no evidence for the addition of acetonitrile and dimethyl sulfoxide (aprotic solvents). In addition, as time passed, the peak area of spiramycin decreased either in the spiked aqueous sample or milk sample while an increase in the peak area of H

Background: Although no authorization is available for antibiotics to treat bee diseases, some veterinary compounds are used by beekeepers, and each country sets its own thresholds. Inappropriate and excessive use of these drugs can cause allergic reactions and antibiotic resistance in humans who consume the remaining antibiotic residues in honey and its products. It is, therefore, relevant to monitor the presence of antibiotic residues in this matrix. Objectives: A rapid method for the simultaneous screening of nitrofuran metabolite residues in honey was validated according to Commission Decision 2002/657/EC (C.D 657) and the European guideline for the validation of screening methods for veterinary medicines. Methods: This multi-analytical screening method enables the simultaneous determination of four nitrofuran metabolites [3-amino-2-oxazolidone (AOZ), 3-amino-5-morpholinomethyl-2-oxazolidinone (AMOZ), 1-Aminohydantoin HCl (ADH), and semicarbazide (SEC)] from a single honey sample. Thirty-five honey samples were collected randomly as real samples for screening from Tehran, IR Iran, Germany, and the Netherlands in 2018. Results: For all four antibiotic residues, the positivity threshold T was higher than the cut-off value Fm, and no false-positive results were obtained for three antibiotics (AOZ, AMOZ, and SEC). Detection capabilities (CCβ) of all compounds were under the minimum required performance limit (MRPL) authorized by the European Commission (currently 1 μg/kg). The screening results of 15 domestic and 20 imported honey samples showed that the levels of AOZ in 6.66% and 10% of the samples, the level of AMOZ in 13.33% and 0% of the samples, and the level of SEC in 33.33% and 40% of the samples were less than the cut-off ([in relative light units (RLUs)], respectively. Conclusions: This study found that this technique is valid for detecting and quantifying three antibiotic residues in honey samples at the measured validation levels. This method was simple, rapid, and capable of simultaneously screening three nitrofuran metabolites from a single honey sample.

The high-performance liquid chromatography-mass spectrometry (LC-MS) technique is widely applied to routine analysis in many matrices. Despite the enormous application of LC/MS, this technique is subjected to drawbacks called matrix effects (MEs) that could lead to ion suppression or ion enhancement. This phenomenon can exert a deleterious impact on the ionization efficacy of an analyte and subsequently on the important method performance parameters. LC-MS susceptibility to MEs is the main challenge of this technique in the analysis of complex matrices such as biological and food samples. Nowadays, the assessment, estimation, and overcoming of the MEs before developing a method is mandatory in any analysis. Two main approaches including the post-column infusion and post-extraction spike are proposed to determine the degree of MEs. Different strategies can be adopted to reduce or eliminate MEs depending on the complexity of the matrix. This could be done by improving extraction and clean-up methods, changing the type of ionization employed, optimization of liquid chromatography conditions, and using corrective calibration methods. This review article will provide an overview of the MEs as the Achilles heel of the LC-MS technique, the causes of ME occurrence, their consequences, and systemic approaches towards overcoming MEs during LC-MS-based multi-analyte procedures.

Graphical abstract, Highlights • The assessed Aflatoxin B1 intake for the adults and children through rice consumption exceeds the established safe levels. • The mean and median HI for adults was below one, and mean HI for children was close to one. • Cancer risk through consumption of domestic rice was higher than cancer risk due to consumption of imported rice. • More focus on the reduction of mycotoxins contamination in rice seems to be necessary., Mycotoxins are secondary fungi metabolites that induce acute and chronic toxic effects in humans and animals. In the present study, nine mycotoxins including aflatoxins (AFB1, AFB2, AFG1 and AFG2), fumonisins (FB1 and FB2), Ochratoxin A (OTA), deoxynivalenol (DON), and zearalenone (ZEN) were determined in one hundred rice samples collected from Tehran using high performance liquid chromatography (HPLC) with fluorescence or photodiode array detector. In addition, possible risk to public health was investigated by assessing dietary exposure through rice consumption, the margin of exposure (MOE), respective risk of cancer and hazard index (HI) of the monitored mycotoxins in children and adults. The higher mean levels were determined for DON (102.22 μg.Kg−1), followed by FB1 (85.00 μg.Kg−1). For the rests of mycotoxins the levels did not exceed 20 μg.Kg−1. The estimated AFB1 intake for the adults and children through rice consumption exceeds the safe levels established for both carriers and non-carriers of hepatitis B virus. The mean and median determined exposure levels of OTA, DON ZEN and FB1, were found lower than the Provisional Maximum Tolerable Daily Intake (PMTDI) value for both adults and children of Tehran that consuming domestic and imported rice. The mean HI for adults and median HI for adults and children were below one, and mean HI for children was close to one. All the mean, median and maximum MoE values were

Aldehydes are compounds that are widely used and popular in organic synthesis due to their high reactivity. This advantage is a disadvantage in medicinal chemistry. Due to the ability of aldehydes to participate in nucleophilic reactions (especially in aqueous biological media) and access to nucleophiles such as amino acids and nucleic acids, drugs with aldehyde functional groups are always used with caution and carefully quantified in biological fluids. Our experience in working on biologically active aldehydes indicates the transformation of these groups of compounds in aqueous or alcoholic solution and thus the failure of analytical methods for their accurate monitoring in such media. Both mass spectrometry and Proton nuclear magnetic resonance spectroscopic findings indicate the reaction of spiramycin with water molecules in an aqueous solution, resulting in the conversion of spiramycin to a new molecule with 18 mass unit difference and thus, the residue amount which is measured and reported based on a mass spectrometries method does not show the correct amount of spiramycin in these samples.

Bread constitutes a popular and even daily component of human diet world-wide, Iran included. However, there are concerns that various processing methods such as frying and baking could result in the production of potentially a source of known carcinogens such as acrylamide (AA) and benzo(a)pyrene (BaP). The present study tried to perform a risk assessment on seven categories of bread consumers, based on age and gender, calculating the Target Hazard Quotient (THQ), Incremental Lifetime Cancer Risk (ILCR), and Margin of Exposure (MOE) related to the dietary intake of AA and BaP. AA and BaP were analyzed in 87 bread samples using LC-MS/MS and GC-MS/MS, respectively. The results indicated that more than 94% (mean concentration: 25.9 ng/g) and about 20% (mean concentration: 1.98 ng/g) of the samples were contaminated with AA and BaP, respectively. The THQ of AA intake through bread consumption for seven categories was in the following decreasing order: semi-industrial Sangak bread of Shiraz (SIS-Sh)traditional Sangak bread of Shiraz (TS-Sh)traditional Sangak bread of Tehran (TS-Th)commercial bread of Tehran (C-Th). The non-neoplastic and neoplastic MOE for AA (˂10,000) indicates a high risk of exposure for all people in Tehran and Shiraz through the consumption of all tested bread. Due to the consumption of TS, SIS, and C bread, the BaP MOE for all people in Tehran and Shiraz was10 000, which shows a low health risk for consumers. Our findings showed that ILCR for AA in seven classes of people who had TS-Sh and TS-Th was remarkably higher than ILCR for all categories that consumed the C-Th. BaP ILCR for the people who ingested TS-Th, TS-Sh, SIS-Th, and SIS-Sh was about 2-4 times higher than people who had C-Th. This study indicates that bread is the main source of AA and BaP intake in Iran, which might elevate the cancer risk.

Illegal and excessive use of veterinary antibiotics as a food additive for growth promotion in livestock can lead to allergic reactions and antibiotic resistance, which is a worldwide concern. A biochip-based semi-quantitative screening method of antimicrobial residues in milk was validated based on Commission Decision 2002/657/EC and the European guideline to validate screening methods for veterinary medicines. This multi-analytical screening method enables to determine of 3 beta-lactams (cefalexin, ampicillin, and cefuroxime) simultaneously. Analysis of 20 blank and 20 spiked milk samples showed that for all 3 antibiotic residues, the positivity threshold T was above cut-off value Fm, and no false-positive results were obtained for all 3 antibiotics. All detection capabilities (CCβ) were below Maximum Residue Level (MRL) authorized by European Commission. 47 UHT cow's milk samples collected from Tehran province, IR Iran, were screened, and compliance was found in 100% of samples. This study found that the biochip method is valid to determine antibiotic residues in milk samples at the measured validation levels. The method was fast, simple, and able to simultaneous screen three families of beta-lactams from a single milk sample with almost no sample preparation.

Background: Since the incidence of food adulteration is rising, finding a rapid, accurate, precise, low-cost, user-friendly, high-throughput, ruggedized, and ideally portable method is valuable to combat food fraud. Near-infrared spectroscopy (NIRS), in combination with a chemometrics-based approach, allows potentially rapid, frequent, and in situ measurements in supply chains. Methods: This study focused on the feasibility of a benchtop Fourier-transformation-NIRS apparatus (FT-NIRS, 1000 - 2500 nm) and a portable short wave NIRS device (SW-NIRS, 740 - 1070 nm) for the discrimination of genuine and citric acid-adulterated lime juice samples in a cost-effective manner following chemometrics study. Results: Principal component analysis (PCA) of the spectral data resulted in a noticeable distinction between genuine and adulterated samples. Wavelengths between 1100 - 1400 nm and ‎‎1550 - 1900 nm were found to be more important for the discrimination of samples for the benchtop FT-NIRS data, while variables between 950 - 1050 nm contributed significantly to the discrimination of samples based on the portable SW-NIRS data. Following partial least squares discriminant analysis (PLS-DA) as a discriminant model, standard normal variate (SNV) or multiplicative scatter correction (MSC) transformation of benchtop FT-NIRS data and SNV in combination with the second derivative transformation of portable SW-NIRS data on the training set delivered equal accuracy (94%) in the prediction of the test set. In the soft independent modeling of class analogy (SIMCA) as a class-modeling approach, the overall performances of generated models on the auto-scaled data were 98% and 94.5% for benchtop FT-NIRS and portable SW-NIRS, respectively. Conclusions: As a proof of concept, NIRS technology coupled with appropriate ‎multivariate classification models enables fast detection of citric acid-adulterated ‎lime juices. In addition, the promising results of portable SW-NIRS combined with SIMCA indicated its use as a screening tool for on-site analysis of lime juices at various stages of the food supply chain.

Isotopic signatures and patterns of volatile organic compounds (VOCs) are a useful set of markers for the authenticity assessment of fruit juices. In the present study, the carbon and nitrogen stable isotopes and VOCs fingerprinting of 16 genuine lemon and 16 genuine lime juices as well as 28 citric acid-adulterated lime juices were investigated to discriminate them and reveal the underlying mechanism for their differences. Samples were subjected to isotope ratio mass spectrometry (IRMS) and proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS). Following δ13C and δ15N analysis, no significant difference between genuine lemon (δ13C: -24.50 ± 1.29; δ15N: 5.40 ± 2.06) and genuine lime juices (δ13C: -25.17 ± 0.7; δ15N: 5.30 ± 0.97) was observed due to the same photosynthetic pathway (C3 photosynthetic pathway) of lemon and lime trees. However, Adulterated lime juice samples had higher δ13C values (-14.99 ± 2.79) and lower δ15N (1.23 ± 2.36) values compared to the genuine lemon and genuine lime juices which could be related to the added exogenous commercially available citric acid manufactured by fermenting sugars that follow the C4 photosynthetic pathway. Besides, a positive correlation (r2 = 0.941) between citric acid to iso-citric acid ratios and δ13C values was found in the adulterated samples. No significant difference was observed in the total concentration of VOCs among the analyzed samples. However, for all samples, ions m/z 81 and 137 had the highest concentrations. Exploratory VOC pattern analysis by principal component analysis (PCA) and hierarchical cluster analysis (HCA) revealed the clustering of samples in different groups according to their nature. Besides, extremely adulterated samples were well distinguished from slightly adulterated samples following HCA analysis. The current study provided empirical evidence on the capability of IRMS and PTR-ToF-MS in the discrimination of lemon juice, lime juice, and adulterated lime juices. However, further investigation is required to confirm the promising results of this study.

The aim of this study was to assess the occurrence of Aflatoxins (AFs) including B1, B2, G1 and G2 in commercial cereal-based baby foods by HPLC-FLD method in Iran and related risk assessment in three baby age groups (6-12, 12-18, and 18-24 months) using Monte Carlo simulation approach. Results showed an occurrence ranging from 20% to 60% for B1, B2, and G2 aflatoxins, while AFG1 was not detected in any assessed samples. Exposure and risk assessment was estimated to be two groups (aflatoxin B1 and total aflatoxins). The highest estimated dietary exposure to both AFB1 and total AFs was estimated for 6-12 months aged babies, representing 5.81 ng/kg BW/day and 8.55 ng/kg BW/day, respectively. Overall, the margin of exposures to AFB1 and total AFs were lower than 10,000 in all age groups, indicating a health concern about AFB1 and total AFs exposure through cereal-based baby food consumption. High cancer risk for high consumers (P95) of baby food was also estimated in all age groups, calling for immediate intervention due to serious claims that AFB1, is a highly carcinogenic component, causes hepatocellular carcinoma. Risk ranking results indicated the presence of AFB1 is classified as high risk for babies who consume cereal-based foods, which demands the attention of risk managers to reduce or eliminate this risk for the most vulnerable sector of society, whose aged

Aflatoxin M1 (AFM1) is a 2B Group human carcinogens agent and introduces into the human diet by milk consumption. In the present study 257 raw, 143 pasteurized and 61 UHT milk samples were collecte...

Acrylamide is a chemical, often present in bread, legally classified as carcinogen, mutagen and reproductive toxicant. Since bread is consumed both world-wide and in Iran, determination of acrylamide in different types of breads is of high interest. In the present study, acrylamide was monitored in 56 Sangak and 30 industrial bread samples collected from Tehran and Shiraz, using LC-MS/MS (LOQ = 1 ng/g). In addition, the noncarcinogenic risk (target hazard quotient–THQ) and carcinogenic risk (incremental lifetime cancer risk–ILCR) due to ingestion of acrylamide through bread consumption in children and adults were assessed. Acrylamide was detected in more than 90% of the samples tested. The average daily intake of acrylamide in Iran based on exclusive consumption of Sangak bread, was estimated at 145 ng/kg bw/day. Based on the THQ for bread acrylamide in adults and children, the decreasing risk order was: Shiraz semi-industrial Sangak, Shiraz traditional Sangak, Tehran traditional Sangak, Tehran industrial bread. The ILCR of bread acrylamide calculated for adults and children was higher than the permissible lifetime carcinogenic risk value established by USEPA (1.00E-5). Results show that bread is a major source of acrylamide intake by people in Iran and all consumers regardless of age could be at elevated carcinogenic risk.

In this study, two accurate, precise, selective and sensitive methods were developed for determining aflatoxin M1 (AFM1) in infant formula milk using immunoaffinity column clean-up followed by high performance liquid chromatography (HPLC) with fluorescence detection. The validated methods were used for determination of AFM1 in 29 samples of 6 different infant formula milk brands and the risk of AFM1 in infants aged zero to 6 months old was assessed using cancer risk, Margin of Exposure (MOE) and Hazard Index (HI). Only one sample (3.4%) was contaminated with AFM1. Although the results showed that MOE values for the mean and median exposure to AFM1 was

In the present study, a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous determination of citric acid, iso-citric acid, and malic acid. Method validation was performed by studying accuracy, precision, linearity, limit of detection, and limit of quantification. Besides, the obtained results were compared to a validated HPLC-DAD method. The use of isotopically labeled citric acid as the internal standard allowed the accurate quantitation of organic acids without any significant matrix effects. Following quantification of main organic acids in the hand-squeezed lime juice samples, it was revealed that citric acid, iso-citric acid, and malic acid contents in the Persian lime juices ranged from 48.30 to 66.54 g/L, 0.24 to 0.61 g/L, and 1.73 to 10.49 g/L, respectively. Finally, among 30 industrial and 20 non-industrial lime juice samples collected from the market, 53% of industrial and 60% of non-industrial samples were detected as adulterated based on the citric acid to iso-citric acid ratio (over 300). The results of method validation demonstrated that LC-MS/MS could be used as a confirmatory method for the authenticity assessment of lime juice by regulatory bodies.

In the current study, the reduction in the level of 42 pesticides from different chemical groups in white rice by means of traditional cooking was evaluated. A gas chromatography-mass spectrometry (GC/MS) system in combination with the modified QuEChERS technique as the base of sample preparation method was employed. The spiked rice samples (at 3 levels of 25, 100, and 500 ng/g) were analyzed to determine the reduction percentage of pesticide. Processing factor for each pesticide excepted for one of them was lower than 1. The introduced sample preparation and identification methods showed a precision as well as accuracy. The recovery of pesticides at three concentration levels was in the range of 84.08–105.95%. The highest and lowest percentages of pesticides reduction were reported as 99.8% and 15.6% for dichlorvos and metalaxyl, respectively. Regarding the different chemical groups, the most reduction is belong organophosphorus pesticides and the less reduction can be correlated to organochlorin...

Major databases were searched until January 2019 and 77 eligible studies were included in the meta-analysis to estimate the overall mean of AFM1 in milk in Iran. The mean of AFM1 levels was obtained 55.97 ng/kg (95% CI: 50.09-61.84). However, the pooled estimated mean of AFM1 levels in milk were 94.58 (95% CI: 70.24-118.92), 59.19 (95% CI: 51.84-66.54) and 35.23 ng/kg (95% CI: 31.53-38.92), considering 4, 55 and 18 TLC, ELISA and HPLC-based studies (including 354, 9224 and 2606 samples), respectively. Also, there is a wide variation of AFM1 levels among different geographical regions which were the highest in northern (88.77 ng/kg). The AFM1 contamination of milk taken from the areas with humid climate was higher than the arid climate. AFM1 Levels were the highest in winter (48.70 ng/Kg). The level of AFM1 in pasteurized, raw, and UHT milk were 49.76, 55.08 and 94.81 ng/kg, respectively.

Nowadays, aflatoxin B1 (AFB1) could be considered as one of the most hazardous mycotoxins for humans, and nuts comprise one of the major responsible food categories for human exposure to this mycotoxin. Thus, complete elimination of AFB1 or reduction of its content in nut foods, such as pistachio attracted lots of attentions. In the current study, the efficacy of roasting process by incorporation of lemon juice and/or citric acid on the reduction of AFB1 in contaminated pistachio nuts (AFB1 at two levels of 268 and 383 ng/g) was investigated. Significant degradation of AFB1 (up 93.1% for AFB1) was recorded by applied treatment protocols. Although roasting of 50 g pistachio nuts with 30 ml water, 30 ml lemon juice and 6 g of citric acid at 120 °C for 1 h resulted to a significant degradation (93.1 ± 8.2%) of AFB1, this treatment altered the desired physical properties. Roasting with 30 ml water, 15 ml lemon juice and 2.25 g of citric acid at 120 °C for 1 h reduced the level of AFB1 in 49.2 ± 3.5% of the initial level without a noticeable change in desired appearance of pistachios. Hence, a synergistic effect between heating and lemon juice/citric acid in order to AFB1 degradation was observed. It could be concluded that roasting process with lemon juice and citric acid could be applied as a useful and safe degradation method of AFB1 in naturally contaminated pistachio nuts.

Major databases were searched until January 2019 and 77 eligible studies were included in the meta-analysis to estimate the overall mean of AFM1 in milk in Iran. The mean of AFM1 levels was obtained 55.97 ng/kg (95% CI: 50.09–61.84). However, the pooled estimated mean of AFM1 levels in milk were 94.58 (95% CI: 70.24–118.92), 59.19 (95% CI: 51.84–66.54) and 35.23 ng/kg (95% CI: 31.53–38.92), considering 4, 55 and 18 TLC, ELISA and HPLC-based studies (including 354, 9224 and 2606 samples), respectively. Also, there is a wide variation of AFM1 levels among different geographical regions which were the highest in northern (88.77 ng/kg). The AFM1 contamination of milk taken from the areas with humid climate was higher than the arid climate. AFM1 Levels were the highest in winter (48.70 ng/Kg). The level of AFM1 in pasteurized, raw, and UHT milk were 49.76, 55.08 and 94.81 ng/kg, respectively.

In current study, the effects of Iranian rice cooking method (Kateh) on residue levels of 41 pesticides were investigated. The pesticides were selected according to Iranian National Standards Organization (INSO) regulations and covered 18 permitted and 23 banned pesticides belonging to different chemical classes such as organophosphate, triazole, and carbamate. A 250 g portion of rice sample was soaked in 2.5 L spiked tap water containing studied pesticides at final concentration 2 μg/mL and then, the effects of washing and cooking were investigated. The pesticides were analyzed simultaneously in a single run using positive electrospray ionisation with multiple reaction monitoring (MRM) after extraction with QuEChERS method. The results showed that washing removed different portions of pesticide residues in the range between 12.0-88.1%. Washing effect was not associated with the water solubility of the pesticides but amount of residue binding to rice matrix was a major factor for residue reduction. In Iranian method of rice preparation, cooking process includes boiling and steam cooking. In this study, the amount of the pesticide residues was decreased in the range of 20.7-100%. Under these conditions, volatilization, hydrolysis, and thermal degradation caused the reduction of the pesticide residues.

A multi-residue method for simultaneous determination of 41 LC-amenable pesticides in rice, belonging to different chemical classes has been developed in Iran by LC-MS/MS. For the first time the pesticides were analyzed simultaneously in a single run using positive electrospray ionization with multiple reaction monitoring (MRM) after extraction with slightly modified QuEChERS method. The calibration curve for each analyte was linear over the concentration range of 0.02–1.0 μg/g with a correlation coefficient range between 0.993 and 0.999. The LOQ and LOD were .025 μg/g and 0.008 μg/g respectively, for all 41 pesticides and the mean recoveries obtained for three fortification levels (0.025, 0.08 and 0.250 μg/g) were 71-119% with satisfactory precision (RSD

In this study, a liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was applied for the simultaneous detection and quantification of a broad spectrum of mycotoxins and fungal metabolites in domestic rice in Iran. A total of 20 fungal metabolites were detected in 65 rice samples. The result showed that all of the samples were contaminated to at least one mycotoxin. The most prevalent fungal metabolites were brevianamide F (81.5%), emodin (46.1%) and tryptophol (43.1%). The occurrence of aflatoxin B1 (AFB1), ochratoxin A (OTA), zearalenone (ZEN) and fumonisin B1 (FB1) was 21.5%, 4.6%, 29.2% and 9.2%, respectively. No detectable level of deoxynivelenol was found in any of the samples. The mean level of regulated mycotoxins was lower than the maximum limit. Co-occurrence of AF1-ZEN, ZEN-OTA and FB1-ZEN were observed in 4.6%, 3.1% and 4.6% of samples, respectively. This is the first report indicating the contamination of domestic rice in Iran with mycotoxins such as alternaria metabolites, citrinin, tryptophol and kojic acid.

A fast and simple modified QuEChERS (quick, easy, cheap, rugged and safe) extraction method based on spiked calibration curves and direct sample introduction was developed for determination of Benzo [a] pyrene (BaP) in bread by gas chromatography-mass spectrometry single quadrupole selected ion monitoring (GC/MS-SQ-SIM). Sample preparation includes: extraction of BaP into acetone followed by cleanup with dispersive solid phase extraction. The use of spiked samples for constructing the calibration curve substantially reduced adverse matrix-related effects. The average recovery of BaP at 6 concentration levels was in range of 95-120%. The method was proved to be reproducible with relative standard deviation less than 14.5% for all of the concentration levels. The limit of detection and limit of quantification were 0.3 ng/g and 0.5 ng/g, respectively. Correlation coefficient of 0.997 was obtained for spiked calibration standards over the concentration range of 0.5-20 ng/g. To the best of our knowledge, this is the first time that a QuEChERS method is used for the analysis of BaP in breads. The developed method was used for determination of BaP in 29 traditional (Sangak) and industrial (Senan) bread samples collected from Tehran in 2014. These results showed that two Sangak samples were contaminated with BaP. Therefore, a comprehensive survey for monitoring of BaP in Sangak bread samples seems to be needed. This is the first report concerning contamination of bread samples with BaP in Iran.

Polycyclic aromatic hydrocarbons (PAHs) are classified as persistent and carcinogenic organic pollutants. PAHs contamination has been reported in water. Many of relevant regulatory bodies such as EU and EPA have regulated the limit levels for PAHs in drinking water. In this study, 13 priority polycyclic aromatic hydrocarbons (PAHs) were determined in tap water samples of Tehran and water for injection. Dispersive liquid-liquid microextraction procedure combined with gas chromatography-mass spectrometry was used for the extraction and determination of PAHs in the samples. Under the optimized conditions, the range of extraction recoveries and relative standard deviations (RSDs) of PAHs in water using internal standard (anthracene-d10) were in the range of 71-90% and 4-16%, respectively. Limit of detection for different PAHs were between 0.03 and 0.1 ngmL(-1). The concentration of PAHs in all tap water as well as water for injection samples were lower than the limit of quantification of PAHs. This is the first study addressing the occurrence of PAHs in water for injection samples in Iran using dispersive liquid-liquid micro extraction procedure combined with gas chromatography-mass spectrometry.

Pistachio nut is an important agricultural and economical commodity in Iran. Annually, several hundred tons of pistachio nuts are produced in Iran. Therefore, the country earns substantial amount of hard currency from exporting pistachio nuts. In addition, livelihood of some million people in pistachio-growing area depends on this crop. Traditionally, the European Union (EU) has been one of the major destinations of pistachio exported from Iran. Pistachio nuts are rich sources of fat, and contain linoleic and linolenic fatty acids. However, they are among the commodities with the highest risk of aflatoxins (AF) contamination. As a consequence of detection of unacceptable level of AF in pistachio consignments arriving in EU ports in 1997, special conditions were imposed on Iran pistachio entering the EU. Therefore, extensive efforts were made to overcome the problem. Iranian authorities in collaboration with EU authorities planned a multi-approach intervention to prevent and control AF contamination of Iran pistachio nuts. Iran experience to prevent and control AF contamination in pistachio nuts was fruitful, and Iran pistachio nuts now have significantly lower level of AF contamination. In addition to economic aspects, these improvements have greatly contributed to protection of both local and international consumers from possible health hazard caused by AF contamination. PRACTICAL APPLICATIONS Despite the nutritional value of pistachio nuts, their susceptibility to aflatoxins (AF) contamination is a potential health hazard. This might cause substantial economical losses to the producers as well. In the past decade, Iran, as the largest pistachio producer in the world, has implemented effective interventions to control AF in pistachios. Implemented interventions such as establishing an efficient decision-making system, focusing on preventive methods, applying Hazard Analysis and Critical Control Point, good agricultural practice and good storage practice guidelines, and using accurate and sensitive sampling and analytical methods proved to be effective. As a consequence, in regard to AF contamination, Iran pistachio nut is now substantially safer. Obviously, this has contributed to the protection of both local and international consumers from possible health hazard caused by AF contamination. From the economical point of view, increasing volume of consumable pistachio nuts will also improve the country's earning from pistachio trade without culturing more orchards.

Patulin is a frequent contaminant of moldy and rotten apples and apple products. The aim of this study was to evaluate patulin contamination in 58 apple juices collected from a retail market in Mashhad during winter and spring of 2006. Samples were assayed for patulin by high-performance liquid chromatography. Fifty-four samples were positive for patulin at levels that ranged from 10.5 to 121.8 µg/L, and six samples had patulin levels higher than 50 µg/L. The overall mean of patulin concentration was 29.2 ± 19.5 µg/L. Forty-eight samples had patulin concentration between 5 and 50 µg/L. Although the mean concentration of patulin samples was lower than Iranian maximum tolerated level of 50 µg/L, contamination of 10% of the samples at levels higher than 50 µg/L indicated the need for improving production techniques by the industry. PRACTICAL APPLICATIONS Studies have shown that the concentration of patulin may exceed the determined limits in apple juice and in other fruit products. Its presence can be a potential threat to the health of consumers, particularly children. The results may help us in understanding what should be the level of patulin in apple juice. The awareness of the apple industry of patulin contamination in fruit and the implementation of improved techniques for the production of apple products with reduced patulin concentrations have contributed to the quality of apple juice that are available on the Iranian market.

Aflatoxins (AF) are highly toxic and carcinogenic secondary fungal metabolites and have been detected in various food commodities including pistachio nuts. Pistachio nuts were produced in Iran during March 2002-February 2003 analyzed for aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2) using immunoaffinity column and quantitated by HPLC and/or TLC-scanner. In this regard, 3356 pistachio nut samples were collected. After dividing samples to sub-samples, 10,068 AF analyses were done. Among 10,068 samples analyzed, AFB1 was detected in 3699 samples (36.7% of the total) with the mean and median of 5.9 (+/-41.7) ng/g and 0.1 ng/g, respectively. Total AF (AFT) was detected in 2852 samples (28.3% of the total) with the mean and median of 7.3 (+/-53.2)ng/g and 0.4 ng/g, respectively. AFB1 level in 1191 samples (11.8%) was above the maximum tolerated level (MTL) of AFB1 in pistachio nut in Iran (5 ng/g). Regarding AFT, the mean contamination level (7.3 ng/g) was lower than MTL of AFT in pistachio nut in Iran as well as lower than the proposed draft maximum level of Codex Committee on Food Additives and Contaminants for AFT (15 ng/g), and only 7.5% of samples had levels above the MTL.

A total of 52 corn samples collected in 2000 from four main corn production provinces of Iran (Fars, Kermanshah, Khuzestan, and Mazandaran) were analyzed for contamination with Fusarium verticillioides and fumonisins (FB(1), FB(2), FB(3), and 3-epi-FB(3)). The mean incidence of F. verticillioides (percent of kernels infected) for these four areas was 26.7, 21.4, 24.9, and 59.0%, respectively. The incidence in Mazandaran was significantly (p0.05) above that of the other areas. All samples from Mazandaran were contaminated with fumonisins with a mean level of total fumonisins of 10674 microg/kg. In contrast, the incidence of fumonisin contamination above 10 microg/kg was 53 (8/15), 42 (5/12), and 57% (8/14) in the samples from Fars, Kermanshah, and Khuzestan, respectively, and the corresponding mean total fumonisin levels were 215, 71, and 174 microg/kg, respectively. No statistical differences (p0.05) were observed in the fumonisin levels of the corn samples from these three provinces, which were significantly (p0.05) lower than the fumonisin contamination in samples from Mazandaran.

Fumonisin B(1) (FB(1)) is the most abundant of the fumonisin mycotoxins, mainly produced in maize by F. verticillioides and F. proliferatum. A previous study on the FB1 contamination of maize harvested in Mazandaran and Isfahan Provinces of Iran in 1998 and 1999 demonstrated contamination in both provinces. This present study was undertaken to further investigate the variation in levels of contamination and to estimate possible levels of human exposure to fumonisins in Iran. The mean level of FB(1) in 49 visually healthy maize samples collected from Mazandaran Province during 2000 was 6.14 mg/kg, which is higher than that found during 1998 and 1999 (2.27 and 3.18 mg/kg, respectively). Although these levels are higher than the Iranian legislative limits for fumonisins in maize intended for humans, the relatively low estimated consumption of maize in Iran (3.3 g/person/day) implies that average exposures (0.011 and 0.215 microg/kg body weight/day in Isfahan and Mazandaran, respectively) are within the provisional maximum tolerable daily intake of 2 microg/kg body weight/day set by the Joint FAO/WHO Expert Committee on Food Additives. Nevertheless, certain sections of the population who may consume higher amounts of maize or who may replace all or some of their consumption of other cereals with maize, could well exceed this limit.

With increasing knowledge and awareness of aflatoxins (AFs) as potent sources of health hazards to both human and animals, a great deal of effort has been made to completely eliminate the toxin or reduce its content in foods. Although prevention is the most effective intervention, heat has been used to inactivate AFs in contaminated foodstuff. Nuts as general and especially pistachio nuts are very sensitive commodity to AFs contamination. In this study effect of roasting on reduction of AFs content in pistachio nuts has been tested in a laboratory setting with aiming to suggest an optimal condition for the roasting. Although all treatment protocols showed some degree of AFs degradation (ranging from 17% to 63%), roasting spiked samples at 120 degrees C for 120 min and 150 degrees C for 30-120 min caused substantial reduction of AFs in samples. Treatment of naturally contaminated whole pistachio kernels at 150 degrees C for 30 min significantly reduced level of AFs contamination in samples. Degradation of AFs was both time and temperature dependent. Roasting at 150 degrees C and 120 min condition degraded more than 95% of AFB1 in pistachio. However, the resulted product was not edible. AFs in form of naturally occurrence were more resistant to degradation with heat.

During September 2000, forty samples of preharvest maize from the province of Mazandaran, north Iran, were randomly collected. Samples were analysed for zearalenone (ZEA) by a thin-layer chromatography (TLC) method (AOAC Official Method). ZEA was extracted with chloroform, purified through a chromatographic column containing silica gel, separated on a TLC plate and quantified by densitometry. The analytical method was validated and was adequately reliable and sensitive. The mean recovery rate of ZEA from spiked samples was 92%. The absolute amount of ZEA standard detectable on a TLC plate was 20 ng, giving a limit of detection (LOD) of 100 ng g(-1). In some samples, it was shown that aflatoxins interfere with ZEA. Therefore, to remove this interference, the TLC mobile phase was changed. Data revealed that three of 40 (7.5%) maize samples contained ZEA in the range 100-212 ng g(-1), with a mean of 141+/-51 ng g(-1). This study, which is the first report of ZEA occurrence in Iranian maize, showed that the ZEA level in maize of Mazandaran province was lower than maximum limit for this mycotoxin in Iran.

The occurrence of deoxynivalenol (DON) in retail foods in Tehran (Iran) was determined using high-performance liquid chromatography technique and immunoaffinity column as the clean-up step. A method was validated for analysis of DON in rice, bread, puffed corn snack and wheat flour. The average recoveries and precision (RSD) for DON in different foods ranged 84.2-93.1% and 2.9-12.0%, respectively. A survey of DON was performed on the 72 samples of rice, bread, puffed corn snack, and wheat flour collected from Tehran retail market. The data showed that 10 samples (13.9%) out of 72 samples were contaminated with DON with the maximum level of 368.7 ng/g. The samples had contamination level lower than the maximum tolerated level of DON in foods in Iran. The total intake of DON was under the provisional maximum tolerable daily intake set for DON by the JECFA.

Patulin is a secondary metabolite produced mainly in rotten parts of apples by a wide range of fungi. Due to its mutagenic and teratogenic nature and possible health risks to consumers, many countries have regulations to reduce level of patulin in apple products to as low as practically possible. A survey of the presence of patulin was conducted in 2002 on 65 locally produced commercial apple juice and apple juice concentrates purchased from retail outlets or producers in Iran. In this study 42 samples of apple juice and 23 apple juice concentrate surveyed for patulin contamination. Results of the study showed in 69% of apple juice and 78% of the apple juice concentrates level of patulin found was higher than 15 μg/l. Overall 33% of the apple juice samples had patulin levels higher than 50 μg/l with maximum level of 285 μg/l and 56% of the apple juice concentrates with patulin level of higher than 50 μg/l and maximum level of 148 μg/l. Although the mean concentration of patulin in apple juice samples surveyed was slightly lower than maximum level recommended by the Codex Alimentarious, fairly high incidence of patulin in these samples indicates the need for improving production techniques by industry in order to reduce the incidence and level of patulin contamination in apple juices.

Aflatoxins are a group of mycotoxins produced by Aspergillus species, including A. flavus, A. parasiticus, and A. nomius. A quarter of the world’s food crops are estimated to be affected by mycotoxins; creating a large economical loss in the developed and developing countries (Kumar, Basu, & Rajendran, 2008; Reddy, Reddy, Abbas, Abel, & Muralidharan, 2008; Wagacha & Muthomi, 2008; Xu, Han, Huang, Li, & Jiang, 2008). Other reports indicate even higher contamination rate of aflatoxin (Njobeh, et al., 2009) . Exposure to higher levels of aflatoxin contamination increases cancer incidence, including risk of hepato-cellular carcinoma especially in 6to 9-year-old girls and neural tube defects (Peng & Chen, 2009; Sun, et al., 2011a; Umoh, et al., 2011; Woo, et al., 2011). One of the reason which makes aflatoxins one of the most challenging mycotoxin is the fact that it could be produced by the responsible fungi not only at pre-harvest time but also at post harvest stages including storage. However, later on, lack of regulations or poor enforcement, which make the use of such contaminated commodities inevitable, could lead to severe human and animal diseases too. Aflatoxin B1, B2, G1 and G2 are the most important members of the aflatoxin group, which chemically are coumarin derivatives with a fused dihydrofurofuran moiety. Presence of aflatoxin B1, B2, G1 and G2 may naturally occur in different ratios depending on different matrices. However, it was concluded that when aflatoxins are limited only to AFB1 and AFB2, such ratio is 1.0 to 0.1, while when all four aflatoxins occur (AFB1, AFB2, AFG1 and AFG2), they may be found in a ratio of 1.0:0.1:0.3:0.03 (Abbas, et al., 2010; Kensler, Roebuck, Wogan, & Groopman, 2011). Cereals notably corn, nuts such as peanuts, pistachio and Brazil nuts, oil seeds such as cottonseed, as well as copra, the dried meat of coconut, are some of the commodities with greater risk of aflatoxin contamination (Cornea, Ciuca, Voaides, Gagiu, & Pop, 2011; Head, Swetman, & Nagler, 1999; Idris, Mariod, Elnour, & Mohamed, 2010; Jelinek, Pohland, & Wood, 1989; Liang, Wang, Zhang, Chen, & Li, 2010; Moghadam & Hokmabadi, 2010; Pacheco & Scussel, 2009; Sun, et al., 2011b; Yassin, El-Samawaty, Moslem, Bahkali, & Abd-Elsalam, 2011). Because peanuts, cottonseed and copra constitute the most important source of edible oils, they are of particular interest (Idris, Mariod, Elnour, & Mohamed, 2010). Commodities which

Fifty-one maize samples, intended for animal feed and human consumption, were collected from the four main maize production provinces in Iran and analyzed by high-performance liquid chromatography (HPLC) for contamination by four naturally occurring aflatoxin analogues (AFB1, AFB2, AFG1, and AFG2). AFB1 was detected in 58.3, and 80% of the maize samples obtained from Kermanshah and Mazandaran provinces, respectively. The maximum AFB1 (276.3 μg/kg) and highest level of total aflatoxins (AFT) (316.9 μg/kg) were detected in a maize sample collected from Kermanshah province. The mean aflatoxin level from contaminated samples (52.60 μg/kg) from Kermanshah was significantly higher (P < 0.0001) than those in maize from the other three provinces and exceeded all the maximum tolerated levels (MTLs) set for AFT in maize. The level of AFB1 in 15.68% of the total samples was above the MTL (5 μg/kg) for AFB1 in maize in Iran. The mean contamination level of AFT (23.86 μg/kg) in the positive samples was higher than MTL for maize in Iran (20 μg/kg) intended for animal feed. The levels of AFB1, AFB2, AFG1, and AFG2 ranged between not detected (

Fifty-one strains of Fusarium verticillioides and F. proliferatum isolated from corn collected from four different geographic areas in Iran, namely Fars, Khuzestan, Kermanshah and Mazandaran (an endemic oesophageal cancer (OC) area) were evaluated for their ability to produce fumonisins B1 (FB1), B2 (FB2) and B3 (FB3) in corn culture. Fumonisin levels were determined by high-performance liquid chromatography. All tested strains of F. verticillioides and F. proliferatumproduced fumonisins within a wide range of concentrations, 197-9661 microg/g, 18-1974 microg/g, and 21-1725 microg/g for FB1, FB2, and FB3, respectively. The highest mean concentrations of FB1, FB2, and FB3 were 3897, 806 and 827 microg/g, respectively. Overall, 61% of the F. verticillioides and F. proliferatum strains produced higher levels of FB3 than FB2. The mean ratios of FB1:FB2, FB1:FB3 and FB1:total fumonisins were 8, 7 and 0.7 for F. verticillioides and 5.7, 10.7 and 0.7 for F. proliferatum, respectively. Significant differences in some of the meteorological data (rainfall, relative humidity and minimum temperature) from the four provinces were observed. Fumonisin levels produced by F. verticillioides strains isolated from Khuzestan province (tropical zone) were significantly (P0.01) higher than the other three provinces. This is the first report of the fumonisin-producing ability of F.verticillioides and F. proliferatum strains isolated from corn harvested from different geographic areas in Iran.

The fumonisin B(1) (FB(1)) contamination of maize collected in two areas of Iran during 1999 was determined. The 20 maize samples from Mazandaran Province, situated on the Caspian littoral of Iran, consisted of random samples of farmers' lots and were all contaminated with FB(1) at a mean level of 3.18 mg kg(-1) (range 0.68-7.66 mg kg(-1)). The 10 samples (of the same maize cultivar) from Isfahan Province in central Iran were purchased as maize cobs in local retail markets and had mean FB levels of 0.22 mg kg(-1) (mean of all samples, 6/10 samples positive, range0.01-0.88 mg kg(-1)). The FB levels in Mazandaran, an area of high oesophageal cancer, were significantly (p0.0001) higher than the FB levels found in maize from Isfahan, an area of low oesophageal cancer in Iran.