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1.
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.  相似文献   

2.
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.  相似文献   

3.
Concentrations of five toxic metals were determined in two fish species from Turkish cities during 2010–2011. The obtained lead concentrations for all of the studied Trachurus trachurus (mean 777 μg kg?1) and Cyprinus carpio (mean 439 μg kg?1) samples were found to be higher than the maximum level (ML) of 300 μg kg?1, while Cd concentrations in the same samples were lower than the ML. Mean chromium (501 μg kg?1), Ni (272 μg kg?1) and Cu (785 μg kg?1) concentrations in T. trachurus were significantly higher than in C. carpio (336 μg Cr kg?1, 229 μg Ni kg?1 and 394 μg Cu kg?1), similar to those of Pb and Cd. Measured Pb concentrations in T. trachurus tissues are significantly higher than the ML, while those of Cd in both T. trachurus and C. carpio species were lower than the ML values.  相似文献   

4.
In this study, a total of 35 tree nut samples of walnut, pecan, pine seed, hickory nut and torreya were obtained from 5 farm product markets in Hangzhou, China, and investigated for essential (Cr, Mn, Fe, Mo, Cu, Zn, Se and Sr) and toxic (Al, As, Cd and Pb) elements by inductively coupled plasma–mass spectroscopy. Mean elemental concentrations of different tree nuts were in the following ranges: Cr 0.26–0.78 mg kg–1, Mn 42.1–174 mg kg–1, Fe 33.7–43.9 mg kg–1, Mo 0.11–0.48 mg kg–1, Cu 10.3–17.6 mg kg–1, Zn 21.6–56.1 mg kg–1, Se 0.015–0.051 mg kg–1, Al 1.44–37.6 mg kg–1, As 0.0062–0.047 mg kg–1, Cd 0.016–0.18 mg kg–1 and Pb 0.0069–0.029 mg kg–1. The estimated provisional tolerable daily intake of Al, As, Cd and Pb was much lower than the provisional tolerable daily intake.  相似文献   

5.
This study was conducted to investigate the toxic metal content (Pb, As, Cd and Hg) of 52 frequently prescribed herbal medicines and to identify herbal medicines that exceed the Korea Food and Drug Administration (KFDA) maximum limits. A total of 3534 samples, including 1966 domestic samples and 1568 imported samples, were analysed using an Inductively Coupled Plasma-Mass Spectrometer (ICP-MS). Total amounts of Pb, As, Cd and Hg were significantly different between domestic (0.63 mg kg?1) and imported (0.81 mg kg?1) medicines (< 0.05). Among the 52 kinds of samples, 4 kinds of herbs required quality control for Pb and 12 kinds of herbs required quality control for Cd. No sample contained As and Hg above the limits.  相似文献   

6.
A survey of Iranian waters, sampled from 2010 to 2013, is presented. A total of 128 water samples from 42 different brands of bottled mineral and drinking water were collected and analysed for contamination levels of lead (Pb), cadmium (Cd), copper (Cu), arsenic (As) and mercury (Hg). Determinations were performed using a graphite furnace atomic absorption spectrophotometer for Pb, Cd and Cu, a hydride vapour generation as well as an Arsenator digital kit (Wagtech WTD, Tyne and Wear, UK) for As and a direct mercury analyser for Hg. Arsenic concentration in six bottled gaseous mineral samples was higher than the related limit. Regardless of these, mean concentrations of Pb, Cd, Cu, As and Hg in all types of water samples were 4.50 ± 0.49, 1.08 ± 0.09, 16.11 ± 2.77, 5.80 ± 1.63 and 0.52 ± 0.03 µg L?1, respectively. Values obtained for analysed heavy metals in all samples were permissible according to the limits of national and international standards.  相似文献   

7.
Pulp is a residual product of the sugar industry resulting from the total extraction of sugar contained in the root of sugar beet and is normally used in the form of pulp or pellets as food in the cattle industry. The objective of this work was the simultaneous determination of zinc, cadmium, lead and copper in pellets and dried pulp. For this we have developed a method of analysis using anodic stripping voltammetry in the differential pulse mode (DPASV) at a hanging mercury drop electrode (HMDE) and compared the results with those obtained by means of electrothermal atomic absorption spectrometry (ETAAS). We conclude that DPASV can be used as an alternative method to ETAAS to determine low concentrations of Zn, Cd, Cu and Pb in such samples, having the advantage of allowing the determination of all four metals simultaneously. From the analysis of real samples it can be concluded that Zn is present in the highest concentration, ranging from 3 to 30 mg kg?1, while Cd, Pb and Cu concentrations were always lower than 1, 8 and 8 mg kg?1 respectively. Copyright © 2005 Society of Chemical Industry  相似文献   

8.
The present study was conducted to evaluate the levels of trace metals (Ni, Cd, Cr, Pb and Cu) in Mukunuwenna (Alternanthera sessilis) samples randomly collected from the production and market sites located in and around Colombo District, Sri Lanka, using the Atomic Absorption Spectrophotometry. Significant differences in heavy metal concentrations were observed between both the production sites and market sites (P<0.05). Heavy metal accumulations in Mukunuwenna tested were higher at the market sites than at the crop production sites. The average concentrations (mg kg-1) of heavy metals in Mukunuwenna samples collected from the production sites were estimated as Ni (6.48±6.74), Cd (0.20±0.11), Cr (3.36±2.76), Pb (2.96±2.16) and Cu (11.85±7.51). The mean concentrations (mg kg-1) of Ni, Cd, Cr, Pb and Cu in Mukunuwenna samples collected from different marketing sites were reported as 7.90±5.98, 0.25±0.18, 4.09±3.36, 3.63±3.65, 13.05±5.15 respectively. The highest contaminated field and market samples were reported from the Kolonnawa area. The samples collected from the market sites were subjected to three processing treatments (raw, cooked and stir-fried) and analyzed for heavy metals, in order to find out the effect of food processing techniques on reducing the heavy metal contaminations of Mukunuwenna samples. The average levels (mg kg-1) of metals detected in raw, cooked and stir-fried Mukunuwenna samples were as follows: Ni (2.20±1.04, 1.77±0.84, 1.46±1.03), Cd (0.19±0.11, 0.12±0.07, 0.10±0.06), Cr (2.37±1.58, 2.27±1.57, 2.20±1.54), Pb (0.26±0.39, 0.22±0.34, 0.21±0.34) and Cu (9.59±4.48, 8.29±3.35, 7.45±3.72). The results showed no significant differences in heavy metal contents among three processing methods (P<0.05). Therefore, the type of processing method has a minimal effect on reducing the heavy metal contents of Mukunuwenna samples.  相似文献   

9.
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.  相似文献   

10.
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.  相似文献   

11.
During 2012–2014, 170 samples of export quality raisins were collected from different vendors in Pakistan. The collected samples were analysed for the presence of aflatoxins (AFs) and Ochratoxin A (OTA) contamination using high-performance liquid chromatography technique. The limit of detection and limit of quantification of AFs/OTA were 0.12/0.10 and 0.36/0.30 µg kg?1, respectively. Only 5% of the samples were contaminated with AFs, ranging 0.15–2.58 µg kg?1 with a mean of 0.05 ± 0.26 µg kg?1. None of the raisin samples exhibited AFs contamination above the maximum limit (ML = 4 µg kg?1) as set by the European Union (EU). About 72% of the samples were contaminated with OTA, ranging 0.14–12.75 µg kg?1 with a mean of 2.10 ± 1.9 µg kg?1. However, in 95.3% of the tested samples, OTA level was lower than the ML of 10 µg kg?1 as regulated by the EU. Apparently, a strict and continuous monitoring plan, including regulatory limits, improves food safety and quality for all types of commodities.  相似文献   

12.
A total of 134 samples, consisting of 58 wheat flour, 40 instant noodle and 36 biscuits, were analysed for the presence of deoxynivalenol (DON). The samples were obtained from retail markets of the city of São Paulo during the period 2010–2014. DON was determined by high performance liquid chromatography with ultraviolet detection and immunoaffinity sample clean-up. Method validation followed international guidelines. The LOD and LOQ were 60 and 200 µg kg?1, respectively, considering the three different types of samples analysed. The lowest recovery found in this study was 91.8% with RSD 4.5% for instant noodles. DON was detected in 91.4%, 97.5% and 97.2% of samples wheat flour, instant noodles and biscuits, respectively, resulting in a total of 94.8% with levels ranging from LOD to 1720.0 µg kg?1.  相似文献   

13.
A simplified alternative to the wet digestion sample preparation procedure for roasted ground and instant coffees has been developed and validated for the determination of different elements by inductively coupled plasma optical emission spectrometry (ICP-OES) (Al, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, Zn) and flame atomic absorption spectrometry (FAAS) (Ca, Fe, K, Mg, Na). The proposed procedure, i.e. the ultrasound-assisted solubilisation in aqua regia, is quite fast and simple, requires minimal use of reagents, and demonstrated good analytical performance, i.e. accuracy from ?4.7% to 1.9%, precision within 0.5–8.6% and recovery in the range 93.5–103%. Detection limits of elements were from 0.086 ng ml?1 (Sr) to 40 ng ml?1 (Fe). A preliminary classification of 18 samples of ground and instant coffees was successfully made based on concentrations of selected elements and using principal component analysis and hierarchic cluster analysis.  相似文献   

14.
A simple procedure for the sequential determination of Cd, Cu and Pb in tea leaves by slurry introduction to thermospray flame furnace atomic absorption spectrometry was developed. Detection limits were 0.05 mg?kg?1 for Cd, 2.1 mg?kg?1 for Cu and 0.68 mg?kg?1 for Pb using 0.67 % (m/v) slurries (100 mg/15 mL).  相似文献   

15.
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.  相似文献   

16.
ABSTRACT

Lead (Pb) and cadmium (Cd) were determined in mangrove root crab (Goniopsis cruentata) tissues (in natura) and in two culinary preparations by graphite furnace atomic absorption spectrometry. Mangrove root crab samples from three sampling sites along the Jaguaripe River, Bahia, Brazil, where lead-glazed ceramics are produced, and from two commercial preparations were collected or purchased in March and April 2016. Cd levels in raw and processed samples were below the methods’ limits of detection (0.016 mg kg?1), while Pb levels in the raw tissues were determined only in the gills (0.67 mg kg?1) and in the hepatopancreas (0.14 mg kg?1). However, Pb levels increased from 0.05 to 2.84 mg kg?1 in boiled/sorted muscle and in the traditional stew (with a 57-fold increase), respectively. Pb levels augmented significantly in the processed food due to migration of Pb used in the glazing of cooking ceramic utensils, surpassing the Brazilian and international safety limits.  相似文献   

17.
In 2011, the European Union prohibited the production of polycarbonate (PC) baby bottles due to the toxic effects of the PC monomer bisphenol-A. Therefore, baby bottles made of alternative materials, e.g. polypropylene (PP) or polyethersulphone (PES), are currently marketed. The principal aim of the study was the identification of major compounds migrating from baby bottles using a liquid–liquid extraction followed by GC/MS analysis. A 50% EtOH in water solution was selected as a simulant for milk. After sterilisation of the bottle, three migration experiments were performed during 2 h at 70°C. A non-targeted liquid–liquid extraction with ethyl acetate–n-hexane (1:1) was performed on the simulant samples. Identification of migrants from 24 baby bottles was done using commercially available WILEY and NIST mass spectra libraries. Differences in the migrating compounds and their intensities were observed between the different types of plastics, but also between the same polymer from a different producer. Differences in the migration patterns were perceived as well between the sterilisation and the migrations and within the different migrations. Silicone, Tritan? and PP exhibited a wide variety of migrating compounds, whereas PES and polyamide (PA) showed a lower amount of migrants, though sometimes in relatively large concentrations (azacyclotridecan-2-one up to 250 µg kg?1). Alkanes (especially in PP bottles), phthalates (dibutylphthalate in one PP bottle (±40 µg kg?1) and one silicone bottle (±25 µg kg?1); diisobutylphthalate in one PP (±10 µg kg?1), silicone (up to ±80 µg kg?1); and Tritan? bottle (±30 µg kg?1)), antioxidants (Irgafos 168, degradation products of Irganox 1010 and Irganox 1076), etc. were detected for PP, silicone and Tritan? bottles. Although the concentrations were relatively low, some compounds not authorised by European Union Regulation No. 10/2011, such as 2,4-di-tert-butylphenol (10–100 µg kg?1) or 2-butoxyethyl acetate (about 300 µg kg?1) were detected. Migrating chemicals were identified as confirmed (using a standard) or as tentative (further confirmation required).  相似文献   

18.
In this study, 88 randomly selected samples of butter produced in the Black Sea region of Turkey were purchased from different retail markets during different periods and investigated for toxic and essential elements content. Quantitative analyses of elements in the samples were performed using an inductively coupled plasma-mass spectroscopy (ICP-MS). Mean concentrations of As, Cr, Cu, Fe, Mn, Ni, Pb, Se and Zn in the butter samples were 18.93, 100.32, 384.66, 4199.1, 887.47, 168.64, 56.13, 16.34 and 384.66 µg kg?1, respectively. Cd and Co were detected in 19 (mean content 0.29 µg kg?1) and 81 (mean content 3.81 µg kg?1) samples of 88 butter samples, respectively. However, the dietary intake of these elements by the population of the Black Sea region is currently well below the dietary reference intake (DRI) and provisional tolerable weekly intake (PTWI) levels of essential and toxic elements.  相似文献   

19.
An effective wet digestion procedure for the determination of total iodine contents in milk powder samples was developed utilizing a high-pressure asher technique. The optimized method based on a two-stage digestion procedure. In the first stage, 500 mg samples were digested at 300 °C for 2 h using 15.2 mol L?1 HNO3 (5 mL) and 30 % H2O2 (3 mL). After the first digestion stage, digestion vessels were allowed to cool down and 1.2 mL of 20 % (w/v) Na2S2O8 solution was added as an additional oxidizing agent to the samples. After that, the vessels were closed, and they were heated at 100 °C for 30 min, resulting in clear and colorless sample solutions. Iodine concentrations in the digested samples were measured with inductively coupled plasma mass spectrometry. The accuracy of the optimized method was confirmed by analyzing milk powder reference material (BCR-151, milk powder). The obtained value for iodine (5.29?±?0.37 mg kg?1, n?=?6) was in good agreement with the certified value (5.35?±?0.14 mg kg?1). Furthermore, the results obtained for reference material showed that the developed method can be applied also for the determination of other elements, e.g., copper, iron, and lead in the digested milk powder samples.  相似文献   

20.
The occurrence of aflatoxin (aflatoxin B1, aflatoxin B2, aflatoxin G1 (AFG1) and aflatoxin G2 (AFG2)) and heavy metal (Pb, Cd, As and Hg) contamination was determined in 40 industrially produced animal feed samples which were collected from the southwest of Iran. The results indicated that 75% of samples were contaminated by four aflatoxins and the level of AFB1 and sum of aflatoxins were higher than the permissible maximum levels in Iran (5 and 20 µg kg?1, respectively) in all feed samples. A positive correlation was found between four types of aflatoxins in all the tested samples (p < 0.01) and the positive correlation between AFG1 and AFG2 was significant (r2 = 0.708). All feed samples had lead concentrations lower than the maximum EU limit, while 5%, 17% and 42.5% of feed samples had As, Cd and Hg concentrations higher than the maximum limits, respectively.  相似文献   

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