Detection of 5-hydroxymethyl-2-furfural Levels in Selected Chinese Foods by Ultra-High-Performance Liquid Chromatograph Analytical Method

In this study, an ultra-high-performance liquid chromatography method was developed to detection the levels of 5-hydroxymethyl-2-furfural (HMF) in 227 selected food products obtained from the Chinese markets. The performance of the analysis method was evaluated by some quality parameters such as limit of detection (LOD), limit of quantification (LOQ), linearity, recovery, and run-to-run (n?=?6) and day-to-day (n?=?18) precisions. The LOD and the LOQ of the method in different food matrices ranged from 0.15 to 0.50 and from 0.35 to 1.20 mg kg^?1, respectively. The results from this study showed that HMF was mostly detected in all samples selected. HMF contents in different samples varied greatly according to the raw materials and processing conditions. The highest level of HMF was found in preserved fruits and ground coffee, with average levels of 409.6 and 409.9 mg kg^?1, respectively. Preliminary estimates of HMF exposure from foods in the Chinese population was estimated to be 0.12 mg kg^?1 body weight day^?1, which is relatively low compared with the result reported by JECFA and European Food Safety Authority.     

Rapid and sensitive method for the determination of four EU marker polycyclic aromatic hydrocarbons in cereal-based foods using isotope-dilution GC/MS

A rapid and sensitive method has been developed for the determination of the four European Union marker polycyclic aromatic hydrocarbons (PAHs; benz[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene) in some cereal-based foods. The method is based on pressurised liquid extraction (PLE), solid-phase extraction clean-up (SPE) and isotope-dilution gas chromatography with mass-spectrometric detection (GC/MS). The developed method was calibrated for the content range of 0.05–12.5 µg kg^?1 (expressed on a product basis). Recoveries of PAH were monitored in each sample via the recovery of ¹³C-labelled PAHs. Recovery values were in the range between 86% and 91%, with relative standard deviations (RSDs) between 5% and 9%. The achieved limits of detection for all analytes were below 0.05 µg kg^?1. The applicability of the method for the analysis of routine samples was studied by the analysis of a set of commercial bread and breakfast cereal samples. In all analysed samples, benzo[a]pyrene (BAP) was the most prevalent PAH with the content between 0.09 and 0.30 µg kg^?1. On average, samples showed low levels of the sum of the four EU marker PAHs (ΣPAH4) that ranged between 0.11 and 0.22 µg kg^?1 for bread samples and between 0.23 and 0.87 µg kg^?1 for breakfast cereal samples. The developed method was found suitable for the determination of PAHs in cereal-based foods like cornflakes and breads with total relative fat contents below 3.5%.     

Multi-Residue Determination of Pesticides in Açai Tropical Fruit (Euterpe oleracea) by Matrix Solid-Phase Dispersion Combined with Liquid Chromatography

An extraction method based on matrix solid phase dispersion was developed to determine bromuconazole, fenbuconazole, parathion-methyl, kresoxim-methyl, and teflubenzuron in açai using liquid chromatography with ultraviolet diode array detector. The best results were obtained using 1.0 g of açai, 3.0 g of neutral alumina as the dispersant sorbent, and cyclohexane/ethyl acetate (1:1, v/v, 20 mL) as an eluting solvent. The method was validated using açai samples fortified with pesticides at three concentration levels (0.25, 0.5, and 1.0 mg kg^?1). Average recoveries (seven replicates) ranged from 66 to 119 %, with relative standard deviations between 1.4 and 20 %. The detection and quantification limits for açai ranged from 0.02 to 0.05 mg kg^?1 and from 0.05 to 0.1 mg kg^?1, respectively.     

3-Monochloropropane-1,2-diol fatty acid esters in commercial deep-fat fried foods

Levels of 3-monochloropropane-1,2-diol (3-MCPD) fatty acid esters were evaluated in commercial deep-fat fried foods from the Brazilian market using a GC-MS method preceded by acid-catalysed methanolysis. A limit of detection of 0.04 mg kg^?1, a limit of quantitation of 0.08 mg kg^?1, mean recoveries varying from 82% to 92%, and coefficients of variation ranging from 2.5% to 5.0% for repeatability and from 3.6% to 6.5% for within-laboratory reproducibility were obtained during in-house validation. The levels of the compounds in the evaluated samples, expressed as free 3-MCPD equivalent, ranged from not detected to 0.99 mg kg^?1, and the highest concentrations were observed in samples of chopped onion and garlic. A preliminary estimation of 3-MCPD intake using these occurrence data suggested low risks to human health, but a potential concern may arise in particular cases of consumers of fried food.     

Migration of melamine from can coatings cross-linked with melamine-based resins,into food simulants and foods

Resins based on melamine-formaldehyde and related analogues such as methylolated melamine are used to cross-link coatings used inside food cans and on the metal closures of glass jars. Thirteen commercially coated cans and closures representing 80% of the European market were tested using simulants under realistic industrial heat-processing conditions for canned and jarred foods. The food simulants and the retort conditions used were 3% acetic acid for 1?h at 100°C and 10% ethanol for 1?h at 130°C. The highest migration level seen for melamine into simulant was 332?µg?kg^?1. There was no detectable migration of the melamine analogues cyanuric acid (<1?µg?kg^?1) or ammelide (<5?µg?kg^?1) from any sample. Twelve of the thirteen samples released no detectable ammeline (<5?µg?kg^?1) but the coating giving the highest release of melamine did also release ammeline at 8?µg?kg^?1 with the higher of the two process temperatures used. Migration experiments into food simulant and foods themselves were then conducted using two experimental coatings made using amino-based cross-linking resins. Coated metal panels were exposed to the food simulant 10% (v/v) aqueous ethanol and to three foodstuffs under a range of time and temperature conditions both in the laboratory and in a commercial food canning facility using proprietary time and temperature conditions. The highest migration into a food was 152?µg?kg^?1 from the first coating processed for a long time at a moderate sterilisation temperature. The highest migration into simulant was also from this coating at 220?µg?kg^?1 when processed at 134°C for 60?min, dropping to 190?µg?kg^?1 when processed at 123°C for 70?min. Migration from the second coating was quite uniformly two to three times lower under all tests. These migration results were significantly higher than the levels of melamine extractable using 95% ethanol at room temperature. The experiments show that commercial canning and retorting can be mimicked in an acceptable way using laboratory tests with an autoclave or a simple pressure cooker. The results overall show there is hydrolytic degradation of the melamine cross-linked resins to release additional melamine. There is a strong influence of the temperature of heat treatment applied with foods or simulants but only a minor influence of time of heating and only a minor influence, if any, of food/simulant acidity.     

Tissue deposition and residue depletion of melamine in fattening pigs following oral administration

The adulteration of animal feed as well as milk products with melamine has led to concerns about the ability to establish appropriate withdrawal intervals to ensure food safety. Two experiments were conducted in this study. The first was to investigate the deposition and depletion of melamine in blood and tissues of pigs exposed to adulterated feed with high doses of melamine. A total of 500 or 1000 mg kg^–1 melamine was added to the diet for fattening pigs (initial BW = ±60.24 kg). Melamine residues were detected in tissues (brain, duodenum, liver, heart, muscle and kidney) by LC-MS/MS. Dose-dependent effects were found between melamine residual concentration and its dose in feed. Five days after the withdrawal of melamine from the diets, the residue concentration in tissues fell below 2.5 mg kg^–1. In the second experiment, blood samples were taken at different time points from fattening pigs (BW = 100 kg) fed with adulterated feed with 1000 mg kg^–1 of melamine for 42 days. Results from the pharmacokinetics analysis showed that it would take 83 h for the melamine level in plasma depleting to the safe level of 50 ng ml^–1 after an expose of 1000 mg kg^–1 melamine contaminated feed for 42 days.     

Determination of moulds and mycotoxins in dry dog and cat food using liquid chromatography with mass spectrometry and fluorescence detection

In this study moulds and 12 mycotoxins in dry pet food samples (25 for dogs and 24 for cats) were determined. Primary moulds identified were Aspergillus, Mucor and Penicillium, found in 55% of the samples. Deoxynivalenol and zearalenone (ZEN) were detected in all samples with mean respective concentrations being 97.3 and 38.3 µg kg^?1 in cat food and 114 and 20.1 µg kg^?1 in dog food. T-2 and HT-2 toxins were present in 88% and 84% of the samples, respectively. Two samples contained fumonisins, with a maximum concentration of 108 µg kg^?1. Aflatoxin B₁ and ochratoxin A were detected in 8% and 45% of the samples, respectively. The measured mould and mycotoxin levels were consistent with results obtained by other studies. However, potential exposure to relatively high concentrations of an oestrogen mycotoxin as is ZEN, especially when in combination with other mycotoxins, needs attention.     

The application of d-SPE in the QuEChERS method for the determination of PAHs in food of animal origin with GC–MS detection

This paper reports the evaluation of the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method for the determination of polycyclic aromatic hydrocarbons (PAHs) in food of animal origin with GC–MS detection. Although in the available literature, there is a lot of information about sample preparation method for PAHs determination in food samples, but the QuEChERS method application for PAHs determination in food of animal origin has not been reported as yet. The results showed that the best recovery ratios 72.4–110.8 % with relative standard deviation lower than 10 % for all determined compounds were received for the method with ethyl acetate as an extraction solvent, primary–secondary amine and C₁₈ sorbents and evaporation to dryness and dissolving the residues in the hexane. The limit of quantification ranged from 0.0003 to 0.0030 mg kg^?1 for pyrene and benzo[a]anthracene, respectively. This method was also used for the determination of PAHs in 15 samples of pork ham. In 8 of 15 samples selected, PAHs were identified. It was observed that in 6 cooked ham and one smoked and cooked samples, any PAHs were found. In other samples, which were smoked and roasted, some low concentration of PAHs was detected. In one sample benzo[a]pyrene (0.0015 mg kg^?1), in one sample benzo[b]fluoranthene (0.0015 mg kg^?1) and in one sample chrysene (0.0024 mg kg^?1) were detected. A number of other less harmful PAHs were also determined. There were no exceedances of maximum levels (according to Commission Regulation (EU) No 835/2011) for determined PAHs in any of the analysed samples.     

Assessment of the dietary intake of propylene glycol in the Korean population

An improved method for the analysis of propylene glycol (PG) in foods using a gas chromatography-flame ionisation detector (GC-FID), with confirmation by GC-MS, was validated by measuring several analytical parameters. The PG concentrations in 1073 products available in Korean markets were determined. PG was detected in 74.1% of the samples, in a concentration range from the limit of detection (n.d., 0.39 μg ml^?1) to 12,819.9 mg kg^?1. The Korea National Health and Nutrition Examination Survey (KNHANES) 2011–2013 reported the mean intake levels of PG from all sources by the general population and consumers were 26.3 mg day^?1 (0.52 mg kg^?1 day^?1) and 34.3 mg day^?1 (0.67 mg kg^?1 day^?1), respectively. The 95th percentile intake levels of the general population and consumers were 123.6 mg day^?1 (2.39 mg kg^?1 day^?1) and 146.3 mg day^?1 (2.86 mg kg^?1 day^?1), respectively. In all groups of the general population, breads were the main contributors to the total PG intake. These reports provide a current perspective on the daily intake of PG in the Korean population.     

Cadmium and lead in female cattle livers and kidneys from Vojvodina,northern Serbia

ABSTRACT

Concentrations of cadmium (Cd) and lead (Pb) were determined in livers (n = 52) and kidneys (n = 52) of female cattle (345–2717 days old) from dairy farms in the region Vojvodina. Cd and Pb were analysed by inductively coupled plasma-optical emission spectrometry, after microwave digestion. Cd and Pb concentrations did not exceed the Serbian and European maximum set limits in any sample. The Cd concentrations in the livers and kidneys ranged from 0.033 to 0.151 mg kg^?1 wet weight and from 0.055 to 0.510 mg kg^?1 wet weight, respectively. The corresponding Pb concentrations were 0.015-0.159 mg kg^?1 wet weight and 0.021-0.196 mg kg^?1 wet weight, respectively. Mean Cd and Pb concentrations were significantly lower (p < 0.001) in the liver (0.072 and 0.053 mg kg^?1 wet weight) than in the kidney (0.190 and 0.075 mg kg^?1 wet weight). There were good correlations between Cd in liver and Cd in kidney, Pb in liver and Pb in kidney, Cd level and age and Pb level and age in both tissues.     

A Highly Sensitive Method for the Determination of Thiophanate Methyl,Cyromazine, and Their Metabolites in Edible Fungi by Ultra-Performance Liquid Chromatography Using Accelerated Solvent Extraction and Cleanup with Solid-Phase Extraction

A highly sensitive ultra-performance liquid chromatographic method with diode-array detection was developed for residue determination of thiophanate methyl (TM), cyromazine (CYR), and their metabolites, carbendazim (MBC) and melamine (MEL). Edible fungi samples were treated using accelerated solvent extraction (ASE) followed by cleanup with solid-phase extraction (SPE). Under optimized conditions, good linearity was achieved with a correlation coefficient (r ²) of ≥0.9998. The limit of quantification was 0.36, 0.24, 0.4, and 0.5 μg kg^?1 for MEL, CYR, MBC, and TM, respectively. The intra- and interday precisions (in terms of the relative standard deviation (RSD)) of the four analytes were in the range of 2.3–4.5 and 3.1–6.3 %, respectively. The recoveries for TM, MBC, CYR, and MEL in four edible fungi samples at three spiked levels of 0.6, 6, and 20 μg kg^?1 for TM and MBC and 0.4, 4, and 20 μg kg^?1 for CYR and MEL were in the range of 82–105 % with RSDs below 5.6 %. The proposed method can be used for the routine determination of CYR and MEL in edible fungi with high sensitivity and accuracy as well as low consumption of reagents.     

Air-Agitated Cloud-Point Extraction Coupled with High-Performance Liquid Chromatography for Determination of Heterocyclic Aromatic Amines in Smoked Sausages

An air-agitated cloud-point extraction procedure (AACPE), which is a new generation of cloud-point extraction procedure, has been investigated for extraction and preconcentration of four heterocyclic amines (i.e., 2-Amino-3,4-dimethyl-3H-imidazo[4,5-f]quinoline (MeIQ), 2-Amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx), 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and 1-methyl-9H-pyrido[3,4-B]indole (harmane)) prior to high-performance liquid chromatography (HPLC). In order to enhance the extraction efficiency, the mixture of the aqueous sample solution and extraction solvent (Triton X-114) was repeatedly aspirated and dispensed using a syringe. Various parameters affecting the extraction efficiency of the AACPE procedure, including type and amount of salt, concentration of Triton X-114, extraction time (or number of air agitations), and centrifugation time, were investigated. No temperature controller was necessary. Under the optimum extraction condition, the linearity was achieved between 0.005 and 1.00 mg kg^?1 with the correlation coefficient (R ²) > 0.999. The low limit of detections (LODs) ranged from 0.001 to 0.003 mg kg^?1 with high enrichment factor (EF) more than 80. Matrix-matched calibration has been used for analysis of the target analytes in real samples. The applicability of the developed procedure was successfully evaluated by the determination of the heterocyclic amines in smoked sausage samples.     

Sodium benzoate and potassium sorbate preservatives in food stuffs in Iran

A high-performance liquid chromatography method was applied for the determination of the levels of benzoate and sorbate in 400 food samples, including pickled cucumbers, canned tomato pastes, sour cherry jams, soft drinks, fruit juices and dairy products (UF-Feta cheeses, Lighvan cheeses, lactic cheeses, yogurts and doogh). The results showed that 270 (67.5%) of all samples contained benzoate ranging from 11.9 to 288.5 mg kg^?1 in lactic cheese and fruit juice, respectively. The levels of sorbate in 98 (24.5%) of the samples were 20.1 to 284.3 mg kg^?1 in doogh and fruit juice, respectively. Moreover, benzoate was detected in all dairy products ranging from 11.9 mg kg^?1 in lactic cheese to 91.2 mg kg^?1 in UF-Feta cheese. A low concentration of benzoate could originate naturally, due to specific biochemical mechanisms during cheese, yogurt and doogh maturation. In conclusion, a minimum level for benzoate in dairy products should be defined in the legislation.     

Use of 4-chloro-3, 5-dinitrobenzotrifluoride (CNBF) Derivatization and Ultrahigh-performance Liquid Chromatography Tandem Mass Spectrometry for the Determination of 20 Free Amino Acids in Chinese Jujube Date

Ultrahigh-performance liquid chromatography tandem mass spectrometry with 4-chloro-3,5-dinitrobenzotrifluoride (CNBF) derivatization was developed for simultaneous determination of 20 free amino acids in Chinese jujube date. The MS/MS conditions, choice of mobile phase, the extraction process, and matrix effects were studied with a view to a method of optimization. The limits of detection for measurement of the amino acids ranged from 0.8 to 600.0 μg L^?1. The correlation coefficients (r²?≥?0.9947) indicated good correlation between the concentrations of amino acids and the peak areas for the CNBF-derivatives. Recoveries for samples spiked at 25.0, 50.0, and 100.0 mg kg^?1 ranged from 66.3 to 106.6 % (except tryptophan spiked at 25.0 and 50.0 mg kg^?1, which provided recoveries of 61.2 and 60.4 %, and tyrosine spiked at three different concentrations, which provided recoveries of 54.8–58.6 %), with relative standard deviation values of less than 9.1 %.     

Estimate of dietary exposure to sulphites in child and adult populations in the Basque Country

Sulphites are widely used as a preservative and antioxidant additive in food. The aim of this study was to assess dietary sulphite intake in adults aged 35–65 years and in children aged 4–18 years living in the Basque Country, northern Spain. We determined sulphite concentrations in 909 samples covering 16 food types. The maximum permitted levels were exceeded in 17% of samples. Making recommended assumptions for non-quantifiable results, estimates of mean lower and upper bounds were calculated for sulphite concentrations in each food type. These sulphite data were combined with consumption data derived from 8417 adults from the European Prospective Investigation in Cancer and Nutrition cohort in Gipuzkoa, recruited in 1992–1995 using a diet history method, and 1055 children from the Basque Country Nutrition Children Survey, conducted in 2004–2005 using two 24-h recall questionnaires to assess diet. The results were compared with the acceptable daily intake (ADI) proposed by the Joint Expert Committee on Food Additives (JECFA). The mean dietary exposure to sulphites was 0.08 mg kg^?1 bw day^?1, only 11% of the ADI in the overall group of children (4–18 years old), but the acceptable intake was exceeded by 4% of 4–6 year olds. For the adults (35–65 years old), the mean dietary exposure was 0.31 mg kg^?1 bw day^?1, 45% of the ADI, but the acceptable intake was exceeded in 14.6% of cases. The major contributing foods were minced meat and other meat products for children and wine for adults.     

Simultaneous Determination of Alkaloids in Green Coffee Beans from Ethiopia: Chemometric Evaluation of Geographical Origin

The alkaloid compositions of 99 green coffee (Coffea arabica L.) bean samples comprising eight varieties (Harar, Jimma, Kaffa, Wollega, Sidama, Yirgachefe, Benishangul and Finoteselam) from the major production regions of Ethiopia were investigated. High performance liquid chromatography was applied for the simultaneous determination of four coffee alkaloids in the aqueous extracts of the beans. The limits of detection for the method were established as 13 mg kg^?1 for trigonelline, 7 mg kg^?1 for theobromine, 8.5 mg kg^?1 for caffeine and 4 mg kg^?1 for theophylline in the dry coffee beans. Theophylline was not detected in any of the samples. The determined concentrations (% w/w dry coffee beans) ranged from 0.98 to 1.32 % for trigonelline, 0.0048 to 0.0094 % for theobromine and 0.87 to 1.38 % for caffeine. The concentrations of the alkaloids varied significantly, depending on the geographical origin of the beans. Theobromine was not detected in coffee beans from the East (Harar coffees), and its absence in samples can be used to ascertain whether the coffee originates from this region. Coffee beans from the Northwest were characterized by higher concentrations of caffeine. Application of linear discriminant analysis provided 75 % correct classification of samples into the respective production regions, with a 74 % prediction success rate. The moderate classification efficiency obtained when using alkaloid data demonstrates the potential of using this class of compounds in discriminant models for determination of the geographical origin of green coffee beans from Ethiopia.     

Risk assessment of dietary exposure to tryptamine for the Austrian population

ABSTRACT

Tryptamine acts as a neuromodulator and vasoactive agent in the human body. Dose–response data on dietary tryptamine are scarce and neither a toxicological threshold value nor tolerable levels in foods have been established so far. This paper reviews dose–response characteristics and toxicological effects of tryptamine as well as tryptamine contents in food, estimates dietary exposure of Austrian consumers, and calculates risk-based maximum tolerable limits for food categories. A dose without effect of 8 mg kg^?1 body weight day^?1 was derived from literature data. Dietary exposure via fish/seafood, beer, cheese and meat products was estimated for Austrian schoolchildren, female and male consumers, based on 543 food samples analysed in Austria 2010–15 and on food consumption data from 2008. Even worst-case estimates based on very high tryptamine contents reported in the literature did not exceed 5.9 mg kg^?1 body weight day^?1, and thus were below the dose without effect. Maximum tolerable levels for food commodities were calculated for high-consumption scenarios (95th percentile of female Austrian consumers). For fresh/cooked fish, preserved fish, cheese, raw sausage, condiments, sauerkraut and fermented tofu, maximum tolerable levels were 1650, 3200, 2840, 4800, 14,120, 1740 and 2400 mg kg^?1, respectively. For beer, the maximum tolerable limit of 65 mg kg^?1 included an uncertainty factor of 10. None of the Austrian occurrence data exceeded these levels (in fact, only 3.3% of samples demonstrated measurable amounts of tryptamine), and just one report was found in the literature on a raw fish sample exceeding the respective tolerable level. In sum, dietary intake of tryptamine should not cause adverse health effects in healthy individuals. The assessment did not take into account the combined effects of simultaneously ingested biogenic amines, and increased susceptibility to tryptamine, e.g., due to reduced monoamine oxidase activity.     

Arsenic and lead in foods: a potential threat to human health in Bangladesh

The non-carcinogenic and carcinogenic risk of arsenic and lead to adults and children via daily dietary intake of food composites in Bangladesh was estimated. The target hazard quotients (THQs), hazard index (HI) and target carcinogenic risk (TR) were calculated to evaluate the non-carcinogenic and carcinogenic health risk from arsenic and lead. Most of the individual food composites contain a considerable amount of arsenic and lead. The highest mean concentrations of arsenic were found in cereals (0.254 mg kg^–1 fw) and vegetables (0.250 mg kg^–1 fw), and lead in vegetables (0.714 mg kg^–1 fw) and fish (0.326 mg kg^–1 fw). The results showed the highest THQs of arsenic in cereals and lead in vegetables for both adults and children which exceeded the safe limit (> 1) indicating that cereals and vegetables are the main food items contributing to the potential health risk. The estimated TR from ingesting dietary arsenic and lead from most of the foods exceeded 10^?6, indicating carcinogenic risks for all adult people of the study area.     

Why chlorate occurs in potable water and processed foods: a critical assessment and challenges faced by the food industry

Recently, reports have been published on the occurrence of chlorate mainly in fruits and vegetables. Chlorate is a by-product of chlorinating agents used to disinfect water, and can be expected to be found in varying concentrations in drinking water. Data on potable water taken at 39 sampling points across Europe showed chlorate to range from < 0.003 to 0.803 mg l^–1 with a mean of 0.145 mg l^–1. Chlorate, however, can also be used as a pesticide, but authorisation was withdrawn in the European Union (EU), resulting in a default maximum residue limit (MRL) for foods of 0.01 mg kg^–1. This default MRL has now led to significant problems in the EU, where routinely disinfected water, used in the preparation of food products such as vegetables or fruits, leaves chlorate residues in excess of the default MRL, and in strict legal terms renders the food unmarketable. Due to the paucity of data on the chlorate content of prepared foods in general, we collated chlorate data on more than 3400 samples of mainly prepared foods, including dairy products, meats, fruits, vegetables and different food ingredients/additives. In total, 50.5% of the food samples contained chlorate above 0.01 mg kg^–1, albeit not due to the use of chlorate as a pesticide but mainly due to the occurrence of chlorate as an unavoidable disinfectant by-product. A further entry point of chlorate into foods may be via additives/ingredients that may contain chlorate as a by-product of the manufacturing process (e.g. electrolysis). Of the positive samples in this study, 22.4% revealed chlorate above 0.1 mg kg^–1. In the absence of EU levels for chlorate in water, any future EU regulations must consider the already available WHO guideline value of 0.7 mg l^–1 in potable water, and the continued importance of the usage of oxyhalides for disinfection purposes.     

Heavy metals in vegetables sold in the local market in Jordan

Heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in various vegetables (cabbage, green onion, lettuce, parsley, rocket, spinach, carrot, onion, potato and cauliflower) from the market in Jordan were measured using inductively coupled plasma-mass spectrometry. As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn ranged from 0.009–0.275 mg kg^?1 wet weight, 0.004–0.060 mg kg^?1, 0.003–0.401 mg kg^?1, 0.105–3.51 mg kg^?1, 0.15–1.15 mg kg^?1, 0.93–14.39 mg kg^?1, 0.044–0.702 mg kg^?1, 0.072–0.289 mg kg^?1 and 2.23–6.65 mg kg^?1, respectively. Parsley, followed by spinach, contained the highest concentration of heavy metals. Onion contained high levels of toxic heavy metals. The content of Cu in parsley and spinach and Pb in onion exceeded the Codex limits. However, the daily intake of heavy metals from the tested vegetables was lower than the maximum limits for allowable intake.