Content and daily intake of copper, zinc, lead, cadmium, and mercury from dietary supplements in Mexico.

This study investigates the presence of Cu, Zn, Cd, Pb, and Hg in 24 dietary supplements purchased in different health stores across the city of Hermosillo, located in the northwest of Mexico. Analysis of metals was done by microwave digestion and atomic absorption spectroscopy. The most abundant elements in dietary supplements were Cu (<0.19-137.85 microg/g) and Zn (<2.83-4785.71 microg/g), followed by Pb (<0.003-66.32 microg/g), Cd (<0.001-2.90 microg/g), and Hg (<0.24-0.85 microg/g). The estimated daily intakes of metals were below those recommended by WHO and the Institute of Medicine, showing that little risk from heavy metals is associated with the consumption of the dietary supplements analyzed. However, some products presented more than 10% of the tolerable daily intake of Pb, indicating that production processes should be improved.     

Determination of trace metals in different fish species and sediments from the River Yeşilırmak in Tokat,Turkey

In the presented study, five different fish species and sediment samples were collected from polluted areas, control samples from unpolluted areas in Ye?il?rmak River during 2008–2009. The samples were analyzed using flame and/or graphite furnace atomic absorption spectrometry after various digestion methods. The relative standard deviations (RSD) were found below 10%. The accuracy of the methods was confirmed by certified reference materials. The maximum iron, zinc, copper, lead, manganese, nickel and cadmium concentrations were found to be as 116 (Fe), 63.5 (Zn), 2.5 (Cu), 0.56 (Pb), 9.4 (Mn), 10.2 (Ni) and 0.75 (Cd) μg/g in fish samples. The maximum metal concentration in sediment was 3566 μg/g for Fe, 463 μg/g for Mn, 45.5 μg/g for Zn, 38.7 μg/g for Cu, 17.3 μg/g for Pb, 79.2 μg/g for Ni and 0.55 μg/g for Cd, respectively. Some species is accumulated trace metals at high ratio.     

Assessment of the exposure to ochratoxin A in the province of Lleida,Spain

Exposure to ochratoxin A (OTA) of 279 blood donors of nine localities of the province of Lleida (Spain) was assessed. OTA levels were detected in the blood plasma of the participants by HPLC-fluorescence detection with previous clean-up of the samples by immunoaffinity columns. Limit of detection was 0.075 ng/mL. Participants answered a questionnaire on consumption frequency of foods possibly contaminated with OTA. Foodstuffs were grouped: cereals and derived products, dried fruits and derived products, cacao and derived products, grape juice, wine, beer and coffee. The range of positive samples was 0.11–8.68 ng/mL and the median was 0.54 ng/mL. No differences were found between OTA plasma levels in men and women, neither in the different localities, but there were significant differences among three age groups. Highest consumed foods were cereals and derived products, followed by beer and wine. No correlation was found between food consumption and OTA plasma levels. OTA daily intake was estimated based on OTA plasma concentrations and on the food consumption data combined with food contamination data taken from the literature. Mean values were 1.69 and 1.96 ng/kg body weight/day, respectively. These values are below the latest proposed tolerable daily intake of 14 ng/kg body weight/day.     

Estrogen-like effects of diet-derived cadmium differ from those of orally administered CdCl(2) in the ERE-luc estrogen reporter mouse model

Cadmium (Cd), an environmental and dietary contaminant, has been described to mimic the effects of 17β-estradiol (E₂) in selected model systems when studied as an inorganic salt. However, inorganic Cd salts do not represent the main form of Cd exposure in general human populations. The aims of this study were to compare the estrogen-like effects and the bioavailability of dietary Cd to inorganic CdCl₂. Adult ovariectomized ERE-luc reporter mice were administered two bread based diets containing different concentrations of Cd (17.57 and 49.22 μg/kg, corresponding to oral intakes of 1.8 and 5.1 μg/kg body weight (bw) per day, respectively), inorganic CdCl₂ (1 μg/kg bw per day by gavage) or E₂ (5 μg/kg bw per day pellet) for 21 days. The effects on estrogen signaling were investigated by studying the uterine weights, luciferase activation, and expression of endogenous estrogen target genes. The uterine weight was significantly increased by both CdCl₂ and E₂ but not by the Cd containing diets. All treatments modulated the expression of luciferase and the endogenous estrogen target genes; however, there was no consistent overlap between the responses triggered by the bread diets and the responses stimulated by CdCl₂ or E₂. Oral exposure to Cd was calculated and the concentrations in liver and kidneys quantified to estimate the amount of absorbed Cd retained in tissues. The results suggest significantly lower absorption and/or tissue retention of dietary Cd compared to CdCl₂ following oral exposure. Altogether, our results support previous reports on in vivo estrogenicity of CdCl₂ but do not suggest the same activity for diet bound Cd. This study calls for caution when extrapolating results from pure compound studies (e.g. estrogenicity of CdCl₂) to dietary exposure scenarios (e.g. estrogenicity of diet bound Cd). Further basic research is needed on the mechanisms of interaction between Cd and the estrogen signaling, biologically active species of Cd, and biomarkers of estrogen-like effects of Cd in vivo before human health risk assessment on the hormone disruptive effects of Cd can be carried out.     

Seasonal investigation of trace element contents in commercially valuable fish species from the Black sea,Turkey

Fish species (Sarda sarda, Mulus barbatus ponticus, Trachurus trachurus and Merlangius merlangus) were collected from the Black sea, Turkey between 2008 and 2009 (spring, summer, autumn and winter). The samples were analyzed using flame and graphite furnace atomic absorption spectrometry after microwave digestion. The maximum metal concentrations were found to be as 25.5–41.4 μg/g (Fe), 17.8–25.7 μg/g (Zn), 0.28–0.64 μg/g (Pb), 0.64–0.99 μg/g (Cr), 1.3–3.6 μg/g (Mn), 1.4–1.9 μg/g (Cu), 0.18–0.35 μg/g (Cd) and 0.25–0.42 μg/g (Co) for fish species. The concentration of trace metals in samples is depended on fish species. Some species is accumulated trace metals at high ratio. Trace element levels in analyzed fish species were acceptable to human consumption at nutritional and toxic levels. The levels of lead and cadmium in fish samples were higher than the recommended legal limits.     

Determination of toxic elements in infant formulae by using electrothermal atomic absorption spectrometer

In present work concentrations of toxic elements (TEs), aluminum (Al), cadmium (Cd), and lead (Pb) in seventeen imported samples of infant milk-based (IMF) and infant soy-based formulae (ISF), were measured, to evaluate whether the intakes of understudy TEs accomplished within recommended permissible levels. The TEs were analyzed by electrothermal atomic absorption spectrometer, prior to microwave induced acid digestion. The validity of methodology was tested by simultaneously analyzing certified reference material and standard addition method. It was observed that ISF contains higher concentration of understudy toxic analytes as compared to IMF. The all three TEs, Al, Cd and Pb were detected in different branded infant formulae, in the range of (1070–2170), (10.5–34.4), and (28.7–119) μg/kg, respectively. The estimated intakes of TEs as μg/kg/week for infants (>1 year) through milk formulae are well below the recommended tolerable levels of these elements.     

Determination of essential elements (Cu,Fe and Zn) in juices of commercially available in Pakistan

In present work, the concentration of essential elements, copper (Cu), iron (Fe) and zinc (Zn) were measured in ten different juices, to evaluate whether the intakes of under study nutrients accomplished within recommended permissible levels. Flame atomic absorption spectrometry (FAAS) was used to estimate and evaluate the levels of essential elements such as Cu, Fe and Zn in ten juice samples. The elements were analyzed prior to microwave assisted acid digestion (MAD). For comparison purpose, wet acid digestion (CAD) method was used for determination of essential elements. The accuracy of proposed method was evaluated by performing addition-recovery experiments to prove the reliability of the method. All obtained analytical results by MAD and CAD showed a good agreement at a 95% confidence level. The detection limits of Cu, Fe and Zn were 22.7 μg/L, 3.85 μg/L and 3.05 μg/L. The dietary intakes of all three studied elements have also been estimated.     

Determination of some heavy metals in food and environmental samples by flame atomic absorption spectrometry after coprecipitation

A novel preconcentration procedure based coprecipitation of Cu(II), Co(II), Cd(II), Ni(II), Mn(II), Fe(III) and Pb(II) on thulium hydroxide precipitate has been presented prior to flame atomic absorption spectrometric determination of them in environmental samples. The analytical parameters that influenced the quantitative coprecipitation of analytes including amount of thulium, pH, duration time, etc. were investigated. The effects of alkali, earth alkali, and some transition metals on the recoveries were also studied. Under the optimized conditions, the detection limits (3 sigma, N = 10) for the analytes were in the range of 0.1-1.6 μg/L, respectively. The validation of the presented coprecipitation method was checked by the analysis of certified reference materials (TMDA 54.4 fortified lake water and HR-1 Humber river sediment). The proposed coprecipitation method has been successfully applied for the determination of traces of copper, cobalt, cadmium, nickel, manganese, iron and lead in food and environmental samples.     

Safety evaluation of metal exposure from commonly used moisturizing and skin-lightening creams in Nigeria

The concentrations of ten metals (Cd, Pb, Ni, Cr, Cu, Co, Fe, Mn, Zn and Al) were measured in some commonly used moisturizing and skin-lightening creams in Nigeria with a view to providing information on the risk of exposure to metals from the use of these products. The metal concentrations in these products were measured by atomic absorption spectrometry after acid digestion of the samples. The measured concentrations of metals in the skin moisturizing creams ranged from <0.15 to 6.3 μg/g Cd, <0.02 to 17.5 μg/g Cu, 2.25 to 6.25 μg/g Cr, <0.25 to 124.3 μg/g Al, 0.2 to 7.3 μg/g Pb, <0.03 to 10.7 μg/g Ni, 17.3 to 372.0 μg/g Zn, <0.02 to 1.0 μg/g Co, 17.75 to 28.8 μg/g Mn, <0.1 to 89.8 μg/g Fe while the concentrations of metals in the skin-lightening products ranged from <0.15 to 16.5 μg/g Cd, <0.02 to 10.0 μg/g Cu, 4.25 to 8.0 μg/g Cr, <0.25 to 128.0 μg/g Al, 0.5 to 4.5 μg/g Pb, <0.03 to 1.65 μg/g Ni, 24.7 to 267.5 μg/g Zn, <0.02 to 2.5 μg/g for Co, 19.3 to 31.8 μg/g Mn, 9.5 to 211.63 μg/g Fe. In a significant number (>93%) of the samples investigated the concentrations of Pb, Cd, Ni and Co were below the specified limit, or the maximal limit for impurities in colour additives in cosmetics for external use. However, Cr was found at concentrations above the allergenic limit of 1 μg/g. The results also showed that skin-lightening creams contained higher concentrations of the studied metals than the moisturizing creams, except for Ni, which indicates that persons who uses skin-lightening creams in preference to moisturizing ones, are exposed to higher concentrations of metals.     

Risk assessment of streptomycin and tetracycline residues in meat and milk on Croatian market

In addition to biological hazards like bacteria, viruses, parasites, the occurrence of chemical hazards is another characteristic of modern food production. The use of veterinary medicines in intensive production of animals is conditio sine qua non so it is impossible to avoid in full the presence of their residues in food.This paper presents quantitative risk assessment of streptomycin and tetracycline based on acceptable daily intake, daily consumption of milk and meat in Croatia (0.222 and 0.126 kg/person, respectively) and residues of these two veterinary drugs in this type of food. The median value for streptomycin in milk and meat was 11.50 and 38.00 μg/kg, respectively (milk: average: 15.57 μg/kg; range from 0 to 73.82 μg/kg; meat: average 44.14 μg/kg; range from 0 to 278.35 μg/kg). The median value for tetracycline in milk and meat was 1.50 μg/kg (milk: average 1.5 μg/kg; range, from 0 to 4.26 μg/kg; meat: average 1.62 μg/kg; range from 0 to 5.35 μg/kg). Based on the median value it can be concluded that the estimated daily intake of streptomycin and tetracycline through milk and meat in Croatia is low (streptomycin: 7.33 μg/person/day; tetracycline: 0.52 μg/person/day), and the risk is assessed as negligible.     

FIA离子交换预浓集AAS法测定水中微量元素

本文用流动注射离子交换预浓集与原子吸收光谱在线连接测定了水中痕量Pb,Cd,Mn,Cu,Ni和Zn.灵敏度比以往火焰法提高40～60倍,分析速度为30样/h.并用均匀设计法优选了实验条件。样品回收率为98～103%,相对标准偏差低于1.8%,最小检测浓度分别为2.0μg/L;0.2μg/L;1.0μg/L;2.0μg/L;5.0μg/L;2.0μg/L.     

Assessment of the temporal trend of the dietary exposure to PCDD/Fs and PCBs in Catalonia,over Spain: Health risks

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), as well as those of 18 polychlorinated biphenyls (PCBs), including 12-dioxin like (DL)-PCBs, were measured in foodstuffs randomly acquired in Catalonia (Spain) in November–December 2008. A total of 65 composite samples, belonging to various food groups were analyzed by HRGC/HRMS. The dietary intakes of PCDD/Fs and PCBs were subsequently estimated for four age groups of the population of Catalonia: children, teenagers, adults, and seniors, which were in turn divided according to sex. The highest dietary exposure to PCDD/Fs corresponded to fish and seafood (28.0%), dairy products (15.4%), and oils and fats (10.6%), while that of PCBs corresponded to fish and seafood (58.6%), and dairy products (8.9%). In contrast, the lowest contributions of PCDD/Fs and PCBs corresponded to vegetables, fruits and pulses. Concerning the sum of PCDD/Fs plus DL-PCBs, the current total intake expressed in pg WHO-TEQ/kg per day (0.60) showed a notable decreasing trend with respect to those found in previous surveys performed also in Catalonia in 2000 (3.51) and 2006 (1.12 pg/kg per day). The current dietary intake of PCDDs plus DL-PCBs is similar or lower than that recently reported in studies performed in a number of regions and countries.     

Mineral content and microbiological examination of some white cheese in Jeddah,Saudi Arabia during summer 2008

Different local and exported white cheese samples were collected from different markets in Jeddah during September 2008. Trace and heavy metals including Pb, Zn, Mn, Cu, Fe and Cd were analyzed using atomic absorption spectrometry. The concentration of the tested metals was in the range, Fe⁺⁺ > Zn⁺⁺⁺ > Mn⁺⁺ > Pb⁺⁺ > Cu⁺⁺ > Cd⁺⁺. The mean concentration of 7.63, 7.19, 0.5, 0.47, 0.16 and 0.14 μg/g was recorded for Fe, Zn, Mn, Pb, Cu and Cd, respectively. The concentration of iron ranged from 3.5 to 11.9 μg/g, zinc from 3.4 to 10.5, manganese from 0.12 to 1.0, lead from 0.14 to 1.14, and copper from 0.09 to 0.22. Yeasts and fungi were counted on Sabouraud and Potato Dextrose media and incubation was carried out at 25 °C for 7 and 5 days, respectively. Yeast count and fungi count of cheese were ranged from 0.1 to 0.44 CFU/g and from 0.123 to 1.11 CFU/g, respectively. Three out of 20 samples of cheese were contaminated with toxigenic fungi with 5% contamination level. Aflatoxin G1 was recorded in three samples using immunoadsorbent column chromatography with a range from 7 to 13 ppm.     

Human exposure to polycyclic aromatic hydrocarbons (PAHs) using data from a duplicate diet study in Catalonia,Spain

In this study, the dietary intake of 16 polycyclic aromatic hydrocarbons (PAHs) by the population of Tarragona County (Catalonia, Spain) was assessed using the duplicate diet approach. Duplicate diet samples, prepared as per consumption, were collected during September 2010 in various restaurants offering a variety of daily menus (breakfast, lunch, and dinner). For analysis of PAHs, a total of 90 composite samples were prepared. Analytical procedure of PAHs was performed by means of gas chromatography/mass spectrometry. Intake calculations were made for the standard male adult population. The highest intakes corresponded to acenaphthylene (12.7 μg/day), acenaphthene (12.4 μg/day), and fluorene (11.9 μg/day), while the lowest intake corresponded to dibenz[a,h]anthracene (0.12 μg/day), being also comparatively low those of pyrene, benzo[b]fluoranthene + benzo[j]fluoranthene, benzo[a]pyrene and benzo[ghi]perylene (0.13 μg/day in all cases). The results were compared with data from previous total diet studies (TDS) recently performed in the same geographical area. In the present study, the estimated mean dietary intake for a standard male adult living in Catalonia was 59.2 μg/day, a value notably higher than that found in our recent TDS (6.72 μg/day). However, it is essential to remark that important methodological differences exist between both surveys, reflecting that calculation methods should be similar when the purpose is to compare results from different surveys. In general terms, we conclude that for PAHs, duplicate diet studies may be a good alternative to total diet studies, especially when there are important economical limitations to perform a suitable TDS. The costs associated to the former may be notably lower, as they do not require such an extensive number of samples for chemical analysis. Moreover, a duplicate diet approach may even be more realistic, as cooked foodstuffs are used for dietary exposure assessment.     

Comparison of dry, wet and microwave digestion methods for the multi element determination in some dried fruit samples by ICP-OES

The aim of this study was used to investigate the level of trace metals (Ba, Pb, Cd, Mn, Cr, Co, Ni, Cu, Mn, Zn, Sr and Fe) in some dried fruits (Prunus domestica L., Ficus carica L., Morus alba L., Vitis vinifera L., Prunus armeniaca L., and Malus domestica) samples from Turkey. Trace elements were determined by ICP-OES after dry, wet and microwave digestion methods in dried fruit samples. Validation of the proposed method was carried out by using a NIST-SRM 1515-Apple Leaves certified reference material. Element concentrations in dried fruit samples were 0.33–1.77 (Ba), 0.12–0.54 (Cd), 0.25–1.03 (Co), 0.45–2.30 (Cr), 0.43–2.74 (Cu), 0.56–4.87 (Mn), 0.61–2.54 (Ni), 0.40–2.14 (Pb), 2.16–6.54 (Zn), 0.83–12.02 (Al), 11.82–40.80 (Fe) and 0.16–6.34 (Sr) μg/g. The analytical parameters show that the microwave oven digestion procedure provided best results as compared to the wet and dry digestion procedures. The results were compared with the literature values.     

Ochratoxin A in adult population of Lleida, Spain: Presence in blood plasma and consumption in different regions and seasons

Ochratoxin A (OTA) levels in blood plasma, as well as the consumption of possibly contaminated foodstuffs by adult inhabitants, were determined in three seasons in the plain and the mountain regions of the province of Lleida (Spain). Daily intake of the toxin was estimated in order to evaluate the exposure of the studied population. OTA was extracted from plasma through liquid-liquid extraction followed by immunoaffinity chromatography columns clean-up. Detection was done through HPLC-fluorescence, and limit of detection was 0.018 ng/mL. Consumption data of the participants were obtained by means of a food frequency questionnaire. Occurrence of OTA in plasma was 100%. Range was 0.06-10.92 ng/mL, and median was 0.50 ng/mL. Differences between genders, regions or seasons were not significant, whereas significant differences were found among age groups. Regarding food consumption, significant differences were found between genders, but not between age groups, regions, or seasons. OTA plasma levels were not correlated with food consumption. Distributions of the intake estimations based on plasma levels differed from those based on food consumption and contamination. Mean and median values of the daily intake estimations were below the latest provisional tolerable daily intake of 14 ng/kg bw/day, but some high percentiles were above it.     

Trace element concentrations of some pet foods commercially available in Turkey

Trace element levels in different types of cat and dog foods consumed in Turkey were determined by flame atomic absorption spectrometry after wet digestion method. Data, expressed on a dry weight basis, were analyzed according to food type (cat or dog, and dry or wet), predominant flavour (beef, fish, chicken), and manufacturer country. Good accuracy was ensured by the analysis of standard reference material (NIST-SRM 8418 Wheat Gluten). The levels of investigated trace elements in the samples were determined in the range of 3.33–16.6, 5.78–19.7, 1.66–15.5, 23.9–71.1, 3.28–24.4, 0.58–3.73, and 0.60–2.47 μg/g for Cu, Ni, Pb, Fe, Mn, Cr, and Cd, respectively. The correlation test was also performed to investigate correlations between the metal contents in samples.     

Inorganic cobalt supplementation: Prediction of cobalt levels in whole blood and urine using a biokinetic model

Soluble cobalt (Co) supplements with recommended daily doses up to 1000 μg Co/day are increasingly being marketed to consumers interested in healthy living practices. For example, some athletes may consider using Co supplements as blood doping agents, as Co is known to stimulate erythropoesis. However, the distribution and excretion kinetics of ingested Co are understood in a limited fashion. We used a Co-specific biokinetic model to estimate whole blood and urine Co levels resulting from oral exposure or ingestion of Co in amounts exceeding typical dietary intake rates. Following 10 days of Co supplementation at a rate of 400 to 1000 μg/day, predicted adult Co concentrations range from 1.7 to 10 μg/L in whole blood, and from 20 to 120 μg/L in urine. Chronic supplementation (?1 year) at a rate of 1000 μg Co/day is predicted to result in blood levels of 5.7 to 13 μg/L, and in urine levels from 65 to 150 μg/L. The model predictions are within those measured in humans following ingestion of known doses. The methodology presented in this paper can be used to predict urinary or blood Co levels following acute or chronic occupational incidental ingestion, medicinal therapy, supplemental intake, or other non-occupational exposures.     

Carrier element-free coprecipitation (CEFC) method for separation and pre-concentration of some metal ions in natural water and soil samples

A simple, rapid and sensitive separation/pre-concentration procedure for Cd(II), Cr(III), Co(II), Cu(II), Fe(III), Pb(II) and Mn(II) ions in environmental samples has been established. The present procedure is based on a combination of carrier element-free coprecipitation (CEFC) and flame atomic absorption spectrometric (FAAS) determinations of understudy trace metal ions. A cationic surfactant (N-cetyl N,N,N trimethyl ammonium bromide (CTAB)) as coprecipitant was used without adding any carrier element for coprecipitation of understudy ions. The optimum conditions for the coprecipitation process were investigated on several commonly tested experimental parameters, such as pH of the solution, amount of coprecipitant. The pre-concentration factor was found to be 10. The detection limits corresponding to three times the standard deviation of the blank (N = 20) for Cd(II), Cr(III), Co(II), Cu(II), Fe(III), Pb(II) and Mn(II) ions were found as 0.61, 16.8, 12.7, 1.36, 2.08, 4.30 and 0.22 μg L⁻¹, respectively. The present procedure was successfully applied for separation and pre-concentration of investigated ions in several liquid environmental samples. In order to support the accuracy of the method, the certified reference materials (BCR 141 R calcareous loam soil and CRM025-050 soil) were analyzed. The experimental results are in good agreement with the certified values.     

Accumulation of cadmium in human placenta interacts with the transport of micronutrients to the fetus

Cadmium (Cd) is a widespread, highly toxic environmental pollutant known to accumulate in human placenta. The aim of the present study was to elucidate to what extent the accumulation of Cd in human placenta interacts with the transport of micronutrients to the fetus. Cd and micronutrients were measured in placenta and umbilical cord blood from 44 non-smoking, rural Bangladeshi women, using ICPMS. Metallothionein (MT) protein expression was determined in placenta using Western blot. Cd in placenta (median 110 μg/kg dry weight, 20 μg/kg wet weight) was positively associated with maternal urinary Cd. It was also positively associated with Cd in umbilical cord blood (median 0.16 μg/kg), but negatively associated with zinc (Zn; median 3 mg/kg) in umbilical cord blood. Umbilical cord blood Zn was positively associated with birth anthropometry measures, and the Cd-related impairment of Zn in umbilical cord blood seemed to decrease size at birth. In multivariate analysis, MT protein expression was associated with Cd (positively) in placenta, but not with Zn or copper (Cu) in placenta. In conclusion, the Cd concentrations in placenta were clearly elevated, which seemed to impair Zn transfer to the fetus. Induction of MT explained the placental accumulation of Cd, but not the impairment of Zn transport.