Elements in rice from the Swedish market: 1. Cadmium, lead and arsenic (total and inorganic)

A survey of the levels of cadmium, lead and arsenic in different types of rice available on the Swedish retail market was carried out in 2001-03. The types of rice included long and short grain, brown, white, and parboiled white rice. The mean levels found were as follows: total As: 0.20 mg kg^-1, inorganic As: 0.11 mg kg^-1; Cd: 0.024 mg kg^-1; and Pb: 0.004 mg kg^-1. ICP-MS was used for the determination of As (total and inorganic) after acid digestion. Lead and cadmium were determined using graphite furnace atomic absorption spectrometry (GFAAS) after dry ashing. In countries where rice is a staple food, it may represent a significant contribution in relation to the provisional tolerable weekly intake for Cd and inorganic As.     

Elements in rice on the Swedish market: Part 2. Chromium,copper, iron,manganese, platinum,rubidium, selenium and zinc

A survey of the levels of some essential and non-essential trace elements in different types of rice available on the Swedish retail market was carried out in 2001–03. The types of rice included long and short grain, brown, white, and parboiled white. The mean levels found were: chromium (Cr)?=?0.008 mg kg^?1, copper (Cu)?=?1.9 mg kg^?1, iron (Fe)?=?4.7 mg kg^?1, manganese (Mn)?=?16 mg kg^?1, platinum (Pt)?<?0.0003 mg kg^?1, rubidium (Rb)?=?3.3 mg kg^?1, selenium (Se) =0.1 mg kg^?1; and zinc (Zn)?=?15 mg kg^?1. Inductively coupled plasma-mass spectrometry (ICP-MS) was used for the determination of Pt, Rb, and Se, after acid digestion. All other elements were determined using atomic absorption spectrometry (AAS) after dry ashing. Intake calculations were performed and it was concluded that rice may contribute considerably to the daily requirements of the essential elements Cu, Fe, Mn, Se, and Zn if rice consumption is high. The levels of some elements, e.g. Fe and Mn, were significantly higher in brown compared with white rice.     

Content of selenium, total and inorganic arsenic and bioaccessibility of arsenic in children diets of Mexico

BACKGROUND: The aim of this study was to evaluate the intake of selenium, total and inorganic arsenic and the bioaccessibility of arsenic in diets of Mexican schoolchildren using an in vitro method. RESULTS: Total and inorganic arsenic concentrations in the diets ranged from 0.05 to 1.15 mg kg^?1 dry weight (DW) and from 0.023 to 0.088 mg kg^?1 DW respectively, while selenium levels were between 0.08 and 0.20 mg kg^?1 DW. Daily intake of total and inorganic arsenic ranged from 0.15 to 10.49 µg day^?1 kg^?1 body weight (BW) and from 0.06 to 1.11 µg day^?1 kg^?1 BW respectively, while that of selenium varied from 0.29 to 2.63 µg day^?1 kg^?1 BW. Bioaccessibility of total and inorganic arsenic ranged from 4 to 97% (mean 44 ± 21.5%) and from 33 to 97% (mean 71 ± 22.5%) respectively. CONCLUSION: Inorganic arsenic levels in the diets were low. Therefore there appears to be a low risk of adverse effects resulting from excess inorganic arsenic intake from these diets. Copyright © 2011 Society of Chemical Industry     

Variations in cadmium accumulation among rice cultivars and types and the selection of cultivars for reducing cadmium in the diet

A pot trial was conducted with 52 rice cultivars of different types collected from different origins. The results showed that there were great differences in Cd concentrations in straw, brown rice and grain chaff among the rice cultivars grown in a soil containing a Cd concentration of 100 mg kg^?1; the Cd concentrations in brown rice ranged from 0.22 to 2.86 mg kg^?1. The great genotypic differences in Cd concentrations indicated that it is possible to lower the Cd content of rice through cultivar selection and breeding. Significant differences were found in the Cd concentrations of the rice types of Indica consanguinity and those of Japonica consanguinity, but not between their origins. There were significant correlations between straw and brown rice in Cd concentration and in the total amount of Cd accumulated. The distribution ratios of the Cd accumulated in brown rice to the total Cd accumulation in the above‐ground rice plant varied greatly from 12.9 to 137.8 g kg^?1, and there was significant correlation between the distribution ratios and Cd concentrations in brown rice. These indicated that Cd concentration in rice grain is governed by the transport of Cd from root to shoot and also from shoot to grain. Cd concentrations in brown rice also correlated significantly with some important agronomic traits, as well as with nitrogen concentrations, one of the most important criteria for rice quality. Copyright © 2004 Society of Chemical Industry     

Investigation of Arsenic and Cadmium Contents in Rice Samples in Turkey by Electrothermal Atomic Absorption Spectrometry

Electrothermal atomic absorption spectrometry was the method used for the direct determination of arsenic and cadmium traces in rice samples. The optimum experimental conditions were investigated in the presence of a Pd/Mg(NO₃)₂ modifier. For arsenic and cadmium, the detection limits were 6.1 and 0.7 μg?kg^?1, whereas the characteristic concentrations were 1.33 and 0.067 μg?L^?1, respectively. For the validation of the method, the concentrations of As and Cd in IRMM-804 rice flour and GBW-08503 wheat flour certified reference materials were determined after microwave-assisted digestion of the samples. The results were found within the uncertainty limits of the certified values. The different 25 rice samples sold in Turkey were digested using a microwave system and then analyzed. The average (range) As and Cd concentrations of all samples were 0.0985 (0.0204–0.1708) and 0.0314 (0.0084–0.0775) mg?kg^?1, respectively. The arsenic and cadmium results were at acceptable levels. The average As and Cd amounts taken from rice are below the provisional tolerable weekly intake levels accepted by the World Health Organization. The distribution of analyte concentrations in some selected rice packages was investigated. The concentrations of both analytes were changed in a wide range even in the same packages.     

Heavy metals in spices commonly consumed in Republic of Korea

Levels of lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) were evaluated in 359 samples of commonly consumed spices (cinnamon, parsley, basil, oregano, coriander seed, nutmeg, cumin, bay leaf, fenugreek, rosemary, thyme, fennel, sage, clove, marjoram, tarragon, caraway, dill seed, pepper, and turmeric) from the market in the Republic of Korea. The content of Pb, Cd, and As was assessed by acid wet digestion using a microwave oven and inductively coupled plasma mass spectrometry (ICP-MS). The content of Hg was analysed using a direct mercury analyzer (DMA). Pb, Cd, As, and Hg mean content in spices ranged from 0.039–0.972 mg kg^?1, 0.013–0.315 mg kg^?1, 0.121–0.861 mg kg^?1, and 0.001–0.025 mg kg^?1, respectively.     

Cadmium content in fresh and canned squid (Loligo opalescens) from the Pacific coastal waters of California (USA)

Cadmium (Cd) levels were determined in 70 samples of mantle tissue and 70 whole individual squid (Loligo opalescens; commercially known as California squid). Samples were collected from the coastal zones of California (USA) during the period 2007/2008. To further investigate consumer exposure to processed fishery products, cadmium concentration was also determined in 200 canned samples of squid. Cd concentrations in raw mantle were low, between 0.01 and 0.29 mg kg^?1 and below the tolerance limit of current regulations (1 mg kg^?1). Respective concentrations in whole individuals were significantly higher, ranging from 0.51 to 1.18 mg kg^?1, attributed to the presence of the visceral portion in whole squid samples. Cd concentrations varied in relation to age and sex of squid, indicating that several physiological factors may influence accumulation. Furthermore, canning of squid substantially enhanced Cd levels. Cd concentration ranged 0.17–0.67 mg kg^?1 in canned mantle tissue and 0.86–2.07 mg kg^?1 in canned whole squid samples, due to both concentration after canning and movement of the metal between different tissues. Several biological compounds, including metallothioneins, nucleic acids and enzymes, may affect Cd concentrations in commercial fishery products.     

Immunochromatography for the rapid determination of cadmium concentrations in wheat grain and eggplant

BACKGROUND: A simple and quick on‐site test for trace levels of cadmium (Cd) in food is needed because of the human toxicity of this heavy metal. We developed an immunochromatography kit which uses the antigen‐antibody complex reaction between the Cd–ethylenediaminetetraacetic acid (Cd–EDTA) complex and an anti‐Cd–EDTA antibody. We previously reported the successful use of this kit to determine Cd concentrations in brown rice with respect to the international standard: 0.4 mg kg^?1. Here, we measured, using this immunochromatography kit, Cd concentrations in crops with lower international standards than rice. RESULTS: Cadmium extracted with 0.1 mol L^?1 HCl from wheat grain and fresh eggplant was purified sufficiently using an ion‐exchange column treatment. Appropriate HCl extraction rates and dilution rates for the column eluate were selected; Cd concentrations in wheat grain and fresh eggplant were determined successfully by immunochromatography with respect to the international standards of 0.2 mg kg^?1 and 0.05 mg kg^?1 fresh weight, respectively. CONCLUSION: Approximate Cd concentrations in wheat grain and fresh eggplant can be monitored easily and quickly by this method at locations where facilities for acid digestion and precision analysis are not available. Copyright © 2011 Society of Chemical Industry     

Trace elements in Canadian field peas: a grain safety assurance perspective

Canada is a significant exporter of field peas and, thus, issues of food safety are important in all grain and food products within the international marketplace. Environmental contaminants, such as trace elements, may be present in all foods and, as a result, international standards have been established for a number of toxic trace elements, such as cadmium, lead, mercury and arsenic, in raw food commodities and food products. The Canadian Grain Commission has undertaken a baseline study of various trace elements in Canadian peas to ensure compliance with international food safety legislation. Mean total cadmium content was found to be 0.023 mg kg^?1; arsenic and lead mean values were below the method limit of quantification of 0.050 mg kg^?1 and the total mean mercury level was below the quantification level of 0.002 mg kg^?1. All measured values in the study were below the maximum residue levels (MRLs) established by the FAO and WHO in the Codex Alimentarius. The mean total selenium content was 0.331 mg kg^?1, with 56% of the measured values exceeding the MRL established by the People's Republic of China (PRC) of 0.3 mg kg^?1. No Codex MRL has been established for selenium as it is regarded as an essential trace element for human health and the PRC is currently reviewing its MRL for selenium in light of this fact. For those parts of the world where selenium-deficiency is of nutritional concern, the higher level of selenium in Canadian peas and their products may be of nutritional benefit.     

Contribution of water and cooked rice to an estimation of the dietary intake of inorganic arsenic in a rural village of West Bengal,India

Arsenic contamination of rice plants by arsenic-polluted irrigation groundwater could result in high arsenic concentrations in cooked rice. The main objective of the study was to estimate the total and inorganic arsenic intakes in a rural population of West Bengal, India, through both drinking water and cooked rice. Simulated cooking of rice with different levels of arsenic species in the cooking water was carried out. The presence of arsenic in the cooking water was provided by four arsenic species (arsenite, arsenate, methylarsonate or dimethylarsinate) and at three total arsenic concentrations (50,?250 or 500?µg?l^?1). The results show that the arsenic concentration in cooked rice is always higher than that in raw rice and range from 227 to 1642?µg?kg^?1. The cooking process did not change the arsenic speciation in rice. Cooked rice contributed a mean of 41% to the daily intake of inorganic arsenic. The daily inorganic arsenic intakes for water plus rice were 229, 1024 and 2000?µg?day^?1 for initial arsenic concentrations in the cooking water of 50, 250 and 500?µg?arsenic?l^?1, respectively, compared with the tolerable daily intake which is 150?µg?day^?1.     

Iron fortification and parboiled rice quality: appearance,cooking quality and sensory attributes

BACKGROUND: Iron (Fe) fortification of parboiled rice increases both Fe concentration and bioavailability in milled grains (i.e. white rice). The aim of the present study was to evaluate parboiled rice fortified with 250 and 450 mg Fe kg^?1 paddy rice for its pre‐cooking appearance, cooking quality, basic sensory attributes and overall acceptance in comparison with unfortified parboiled rice in Thailand and local parboiled rice in Bangladesh. RESULTS: Fe fortification at 250 mg Fe kg^?1 paddy rice significantly elevated Fe concentration in white rice to as high as 19.1 mg Fe kg^?1 white rice, compared with 6.2 mg Fe kg^?1 white rice for unfortified parboiled rice, without any adverse impact on consumer acceptance based on the current preliminary assessment. The added Fe was well retained in the cooked rice, with significant residual value for human intake. Panellists in Thailand and Bangladesh did not detect significant differences in the acceptability of parboiled rice fortified at 250 mg Fe kg^?1 paddy rice compared with unfortified and local parboiled rice respectively. However, Fe fortification of parboiled rice at the higher level of 450 mg Fe kg^?1 paddy rice significantly intensified the yellow colour of the grain and changed the off‐flavour, chewiness and flakiness of the cooked Fe‐fortified parboiled rice. This resulted in a low acceptability ranking of parboiled rice fortified at 450 mg Fe kg^?1 paddy rice by panellists in both Thailand and Bangladesh. CONCLUSION: Fe fortification of parboiled rice at an appropriate level (e.g. 250 mg Fe kg^?1 paddy rice) is dosage‐effective and acceptable to rice consumers. Consumer acceptability of Fe‐fortified parboiled rice is closely related to pre‐cooking appearance, cooking quality and sensory attributes. Copyright © 2009 Society of Chemical Industry     

Assessment of mercury and cadmium via seafood consumption in Italy: estimated dietary intake (EWI) and target hazard quotient (THQ)

Mercury (Hg) and cadmium (Cd) were quantified in fish, cephalopods and crustaceans from Italian supermarkets. Sample compliance with European dietary standards as well as human health risks according to provisional tolerable weekly intake (PTWI) and the methodology of target hazard quotient (THQ) were evaluated. Both element levels were under European legal limits, except for some fish having Hg and Cd contents exceeding or equal to critical values. Estimated weekly intakes (Hg: fish = 0.07–1.44 µg kg^?1 bw week^–1; cephalopods = 0.05–0.15 µg kg^?1 bw week^–1; crustaceans = 0.04–0.08 µg kg^?1 bw week^–1; and Cd: fish = 0.04–0.32 µg kg^?1 bw week^–1; cephalopods = 0.07–0.27 µg kg^?1 bw week^–1; crustaceans = 0.05–0.11 µg kg^?1 bw week^–1) as well as THQ < 1 were within safe limits. Although there seems to be no important risks associated with seafood consumption, Hg exposure was in some cases close to safety margins and thus levels of this metal should be under frequent surveillance.     

Soil and vegetable compositional relationships of eight potentially toxic metals in urban garden fields from northern Nigeria

BACKGROUND: Human exposure to heavy metals is attributed to consumption of vegetables raised in polluted soil environment. We examined the concentrations of As, Cd, Co, Cr, Cu, Ni, Pb and Zn in soils and lettuce (Latuca sativa) and amaranthus (Amaranthus caudatus) in 15 garden fields under long‐term wastewater irrigation. RESULTS: The concentrations of As (0.3–2.1 mg kg^?1), Cd (0.07–0.3 mg kg^?1), Co (4.6–9.1 mg kg^?1) and Cr (21.6–36.2 mg kg^?1) in the gardens were consistent with background concentrations in soils, but Ni (12.6–25.7 mg kg^?1), Cu (12.5–24.6 mg kg^?1), Pb (25.7–71.6 mg kg^?1) and Zn (52.3–158 mg kg^?1) concentrations were double the concentrations normally encountered in arable fields in the region. The concentrations of Cd and As in the vegetables were within safe limits, but Co (0.14–0.67 mg kg^?1 fresh weight (fw)) and Ni (1.0–2.7 mg kg^?1 fw) concentrations in lettuce were relatively high for leaf vegetables. The concentration of Pb (0.65–4.80 mg kg^?1 fw) was above safe limit of 0.3 mg kg^?1 fw, while the concentrations of Cu (1.3–2.7 mg kg^?1 fw and Zn (10.2–23.6 mg kg^?1 fw) were close to the unsafe limits for leaf vegetables. There were no strong linear correlations between soil metal concentrations and bio‐concentrations in the vegetable crops. CONCLUSION: We surmise that leaf vegetables can accumulate metals in their tissues to unsafe levels even when total metal concentrations in these soils are below the allowable concentrations in agricultural soils. Copyright © 2008 Society of Chemical Industry     

Trace elements in edible tissues of three shrimp species (Penaeus semisulcatus,Parapenaeus longirostris and Paleomon serratus)

Accumulation levels of trace elements in edible tissues of three shrimp species (Penaeus semisulcatus, Parapenaeus longirostris and Paleomon serratus) from the Gulf of Antalya, Turkey were investigated. Copper (Cu), cadmium (Cd), zinc (Zn), iron (Fe) and manganese (Mn) concentrations were determined by atomic absorption spectrophotometry. The lowest Cu (1.33 mg kg^?1) and Cd (0.23 mg kg^?1) and highest Mn (1.52 mg kg^?1) concentrations were found in P. longirostris, the lowest Zn (6.25 mg kg^?1), Fe (1.84 mg kg^?1) and Mn (0.25 mg kg^?1) concentrations in P. serratus and the highest Cu (6.19 mg kg^?1), Cd (2.36 mg kg^?1), Zn (30.84 mg kg^?1) and Fe (33.89 mg kg^?1) concentrations in P. semisulcatus. The Cd levels detected in P. semisulcatus and P. serratus were above legislative limits. Our results show that there were significant differences in trace element concentrations among the three shrimp species. The highest levels of the five trace elements investigated, with the exception of Mn, were found in edible tissue of P. semisulcatus. Copyright © 2007 Society of Chemical Industry     

Toxic and micronutrient elements in organic,brown and polished rice in Brazil

Concentration levels of As, Cd, Hg, Pb, Tl, Sn, Sb Co, Cu, Mn, Se, Zn, Cr, Ni and Mo in different types of rice cultivated in irrigated fields in Brazil were evaluated. Arsenic, Cd, Pb, Zn, Mn and Cu were found in higher concentrations in brown rice samples, suggesting the prevalence of these elements in the bran. Meanwhile, lower concentrations of Pb, Mo, Cr, Se and Co were found in parboiled rice. Organic rice did not differ of cultivated conventionally rice. Thallium, Hg and Sb were not detected in any rice sample whose limits of detection were 0.7 μg kg^?1, 2.5 μg kg^?1 and 8 μg kg^?1, respectively. The concentrations of the investigated elements were compared with those reported for polished rice and brown rice from other countries, unveiling concentrations in general at the same level for rice produced at non-contaminated sites.     

Mycotoxins,trace elements,and phthalates in marketed rice of different origin and exposure assessment

ABSTRACT

The aim of this study was to determine levels of 11 mycotoxins, 10 trace elements, and 6 phthalates in rice samples from Serbian and Chinese market. Mycotoxins were not detected in any of the analysed rice samples. Results revealed similar median levels for following elements: Mn, 17.5 and 15.7 mg kg^?1; Fe, 2.47 and 2.12 mg kg^?1; Cu, 1.95 and 1.59 mg kg^?1 in marketed samples from Serbia and China, respectively. Median concentration of Ni in Serbian marketed samples was 1.9 times higher than in Chinese ones. The median levels (µg kg^?1) of phthalates ranged from 1.2 (benzylbutyl phthalate [BBP]) – 566 (di(2-ethyl-hexyl) phthalate [DEHP]) and 1.7 (BBP) – 348 (DEHP) in Serbian and Chinese marketed samples, respectively. The results were used to assess daily exposure of Serbian and Chinese adult consumers. The calculated target hazard quotients indicated that the potential risk attributable to the analysed contaminants in rice samples should not be of concern neither for the Serbian nor the Chinese consumers.     

Sensitive determination of cadmium in brown rice and spinach by flame atomic absorption spectrometry with solid-phase extraction

A sensitive flame atomic absorption spectrometry (FAAS) method was developed for the determination of cadmium (Cd) in brown rice and spinach. The method involves extraction with 1?M hydrochloric acid (HCl), followed by a selective pre-concentration by solid-phase extraction (SPE). The pH of the loading sample solution was adjusted to 4.0 for the brown rice and to 5.0 for the spinach. The masking agents, tartrate and citrate, were required for the spinach before pH adjustment. The SPE step achieved a 20-fold enrichment of the sample solution. The limits of quantification (LOQs) were 0.0054?mg?kg^?1 for the brown rice and 0.0022?mg?kg^?1 for the spinach, being more sensitive than those of AOAC Official method 999.10. A single-laboratory validation was performed by testing spiked samples at 0.04 and 0.08?mg?kg^?1 for the brown rice, and 0.02 and 0.04?mg?kg^?1 for the spinach. The average recoveries were 93.3–96.9% with relative standard deviations (RSDs) of 4.1–8.2% for brown rice, and 90.5–91.9% with RSDs of 5.8–10.0% for spinach.     

Survey and risk assessment of trace elements in foods from Taiwan containing red mould rice (Monascus) by ICP-MS

The concentrations of seven trace elements (As, Cd, Cr, Pb, Se, Cu and Zn) in 93 red mould rice (Monascus) food samples in Taipei, Taiwan, were determined by inductively coupled plasma-mass spectrometry (ICP-MS) after wet digestion. The results, calculated in mg?kg^?1 (wet weight) for each sample, revealed the general scenario of food safety in Taiwan: As (0.005–12.04), Cd (<0.0005–2.22), Cr (0.014–6.95), Cu (0.012–8.70), Pb (0.001–0.64), Se (<0.001–1.29) and Zn (0.020–67.02). Three food samples were identified with As concentrations higher than regulatory limits: a dietary supplement sample and a seaweed sample with As concentrations that exceeded the limit of Taiwan's health food standard of 2?mg?kg^?1, and a canned eel sample with an As concentration that exceeded the limit of Canada's fish standard of 3.5?mg?kg^?1. This study suggests that the estimated intakes of these seven trace elements from the consumption of foods containing Monascus pose little risk, as the trace element contents in the majority of samples were lower than the permissible/tolerable intakes per week according to the guidelines recommended by the Food and Agricultural Organization/World Health Organization (FAO/WHO). Moreover, their concentrations in foods containing Monascus differ widely for different food varieties, suggesting that external contaminants and raw materials are the main sources of trace elements. This study shows that ICP-MS is a simple method proposed for the determination of As, Cd, Cr, Pb, Se, Cu, and Zn in foods containing Monascus.     

Exposure to metals and arsenic from yellow and red tuna consumption

ABSTRACT

Tuna is one of the most frequently consumed fish and, as a predator, can biomagnify pollutants. Metal and other elements pollution is an important worldwide concern. Based on these considerations, the aim of this work was to investigate the occurrence of As, Cd, Cr, Ni, Hg and Pb in tuna coming from different FAO areas to evaluate human exposure. The analysis was performed on muscle tissues through a quadrupole inductively coupled mass spectrometry. One hundred thirty-one samples were analysed. One red tuna from the Adriatic Sea and 11 yellow tunas exceeded Pb maximum levels (MLs) with a concentration ranging 0.31–0.86 mg kg^?1; three red tunas from different Mediterranean sub-areas exceeded Hg MLs, with a concentration range 1.19 to 1.80 mg kg^?1. All the Hazard Indexes (HIs) were lower than one, indicating that only a negligible health hazard could derive from the ingestion of tuna, for both average and high consumers. The risk of carcinogenicity from Cr is still under debate at the concentrations detectable in food.     

Phytoavailability, human risk assessment and transfer characteristics of cadmium and zinc contamination from urban gardens in Kano, Nigeria

BACKGROUND: Quantitative data about phytoavailability and transfer into consumed plant parts for heavy metals in intensively managed urban vegetable production areas of sub‐Saharan Africa are scarce. We therefore studied the transfer of zinc (Zn) and cadmium (Cd) from soil to the root and subsequent translocation to edible portions of four vegetables in six urban gardens. RESULTS: While respective diethylenetriaminepentaacetic acid (DTPA)‐available Zn and Cd concentrations ranged from 18 to 66 mg kg^?1 and from 0.19 to 0.35 mg kg^?1, respectively, in soils, total Zn and Cd were 8.4–256 mg kg^?1 and 0.04–1.7 mg kg^?1 in shoot parts. Metal transfer factor (MTF) ratios were higher in Zn (0.2–0.9) than in Cd (0.1–0.6). Our data suggest that total Zn concentration in soil is a reliable indicator to assess its transfer from soil to crop in lettuce, carrot and parsley, while for Cd DTPA‐extractable concentration may be used to estimate soil–crop transfer of Cd in amaranthus and carrot. Overall, Cd was more easily translocated to the aerial plant parts than Zn. CONCLUSION: Zinc and Cd accumulation by vegetables in our soils is mainly a metabolically controlled process. Such accumulation can contaminate the ecosystem but under our conditions intake and ingestion of these metals will likely have to occur over a prolonged period to experience health hazard. Copyright © 2011 Society of Chemical Industry