Dietary exposure to essential and toxic trace elements from a Total diet study in an adult Lebanese urban population

This study assesses, by the Total diet study approach, the adequacy of micronutrient intake (Co, Cu, Fe, Mn, Ni, Zn) and the dietary exposure of a Lebanese adult urban population to two toxic elements (Cd, Pb). The foods that made up the average ‘total diet’ were derived from a previous individual consumption survey. A total of 1215 individual foods were collected, prepared and cooked prior to analysis. Analytical quantification was performed using inductively coupled plasma mass spectrometry. Average daily intakes of Co (11.4 μg/day), Cu (1104.19 μg/day), Fe (13.00 mg/day), Mn (2.04 mg/day), Ni (126.27 μg/day) and Zn (10.97 mg/day) were below toxicological reference values and were found to satisfy nutritional recommendations, except for manganese in men and iron in women. Average dietary exposure to Pb and Cd represented 3.2% and 21.7% of the respective provisional tolerable weekly intakes. Estimates of dietary intakes of iron appeared to be inadequate for 63% of adult women. These findings should constitute a current measure of assessing the adequacy and safety of foods consumed in Lebanon and may be a basis for future monitoring studies.     

Dose-response effects of various metal ions on rat liver metallothionein,glutathione, heme oxygenase,and cytochrome P-450

Adult male rats received ip injections of the maximum tolerable dose (MTD; μmol/kg/day, in parentheses following metal), or a fraction thereof, of Hg (5), Cd (20), Se (25), Ag (65), Cu (75), Co (100), Ni (120), Zn (200), Mn (250), Fe (300), Pb (400), or Cr (400) 36 and 12 hr before sacrifice. MTDs were estimated from previous studies, and at least three serial dilutions ($\text{1}\text{2}$, $\text{1}\text{4}$, $\text{1}\text{8}$, etc.) of the MTDs were tested for each metal. The effects of metal treatment on hepatic heme oxygenase activity (HO), cytochrome P-450, reduced glutathione (GSH) and metallothionein (MT), and renal MT and GSH were determined. Nine metals increased HO at the MTD, but only Cd, Se, Mn, and Pb increased HO at lower doses. These four metals plus Ag and Cr depressed cytochrome P-450 levels at the MTD, but only Cd, Mn, and Pb depressed cytochrome P-450 at a lower dose. Se increased hepatic GSH at the two highest doses, but all other metals had little or no effect. Kidney GSH was increased by all metals except Cd, Ag, Cu, and Cr, to a maximum level of only 150% of control (Pb). Cd and Zn induced hepatic MT in a dose-related manner to 420 and 580% of control, respectively. On a molar basis, Cd was about eight times more potent than Zn in increasing hepatic MT concentration. Hg, Ni, Mn, Fe, Pb, and Cr also significantly increased hepatic MT, but only to 150–200% of control. Pb had a slight but significant effect on hepatic MT at all doses down to 1/16th the MTD. This effect of PB, as well as other metals having a small effect on MT, may be the result of the effects of stress on MT rather than the metal ion per se. Renal MT was effectively induced by Hg, Cd, Cu, Ni, Zn, and Pb. Relatively small amounts of Hg (0.62 μmol/kg/day) significantly increased renal MT when compared to the minimum effective dose of Cd (10 μmol/kg/day) or Zn (50 μmol/kg/day). In conclusion, metals have a number of effects on potential hepatic and renal biochemical defense mechanisms. Most of the metals lacked specificity, affecting a number but not all of the parameters examined. However, of the 12 metals examined, Zn was the most selective in that it produced marked increases in MT and little or no effect on the other parameters, whereas Cd had the broadest effect, altering all parameters except GSH.     

Prediction and risk assessment of five heavy metals in maize and peanut: A case study of Guangxi,China

To assess the contamination levels and health risk of cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn) to human beings, the concentrations of these heavy metals in soil were surveyed and the concentrations in maize and peanut grains were estimated by models. The geo-accumulation index (I _geo) was calculated, and chronic daily intake (CDI), hazard quotient (HQ) and hazard index (HI) were estimated. Results indicated that the concentrations of Cd, Cu, Hg, Pb, and Zn in the soil samples exceeded the limit set by authorities in China. However, the concentrations in maize and peanut grains were rarely higher than the allowable concentrations suggested by the Ministry of Health of China (MHC). In accordance with geo-accumulation, these heavy metals in soil samples were polluted to different extents. Prediction models were developed to effectively assess the health risk of using TOC, Mn, pH, and CaO to human beings. Therefore, the concentrations of these heavy metals in the grains could be decreased by changing their levels in soil. The CDI, HQ, and HI were estimated by estimating concentrations of Cd, Cu, Pb, and Zn in maize grains, indicating that these metals exhibited a slight health risk to adult residents.     

Distribution and ecological assessment of heavy metals in surface sediments of the East Lake, China

Concentrations and risk assessment of chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), lead (Pb), cadmium (Cd) and mercury (Hg) were investigated in 106 samples of surface sediments from the East Lake, China in this study. The mean concentration of Zn was highest among the eight heavy metals (225 mg kg^?1), followed by As (191 mg kg^?1), Cr (145 mg kg^?1), Cu (55 mg kg^?1), Ni (27.1 mg kg^?1), Pb (7.93 mg kg^?1), Cd (0.94 mg kg^?1) and Hg (0.21 mg kg^?1). Niuchao Hu was less polluted by heavy metals compare to the other four lakelets of the East Lake. The correlations among these heavy metals and the results of principal component analysis indicated that the distribution of Cd, Pb and Hg was related to anthropogenic activities, whereas Cu, As and Cr were affected by the parent rocks. Zinc and Ni were influenced both by anthropogenic activities and parent rocks. Based on the Sediment Quality Guidelines, the results of toxicity assessment indicated that adverse effects caused by Cr and As would be expected frequently. Nickel, Zn, Cd and Hg may cause adverse effects occasionally and Cu and Pb may cause toxicity infrequently. Arsenic was found to have the highest acute toxicity by toxic units (TUs), followed by Cr, Ni, Zn, Hg, Cu, Cd and Pb. The potential ecological risk index analysis indicated that As, Cd and Hg had considerable or high ecological risk, whereas Cr, Ni, Cu, Zn and Pb had low ecological risk. The potential ecological risk index (RI) of the heavy metals in the surface sediments of East Lake was 483, indicating considerable ecological risk. Close attention should be paid to pollution of the heavy metals in East Lake, China.     

Metal concentrations in tissues of the Black Sea fish Mugil auratus from Sinop-Icliman,Turkey

Levels of five heavy metals [copper (Cu), lead (Pb), cadmium (Cd), chromium (Cr) and nickel (Ni)] were evaluated in liver and muscle tissues of fish (Mugil auratus) collected from the Black Sea at Sinop-Icliman, Turkey. Sampling and analysis methods are described. Variations of heavy metal concentrations with seasons are discussed. Cr and Ni concentrations were below the limits of detection (< 0.05 and 0.1 microg/g dry weight) in all tissues and seasons. Cu, Pb and Cd were detected within these limits, as microg/kg dry weight, in liver tissue: 0.49-1.30, 0.60-1.21 and 0.15-0.50, and in muscle tissue: 0.30-1.00, 0.57-1.12 and 0.10-0.40, respectively. Cu, Pb and Cd concentrations in these tissues were elevated and the highest heavy metal concentrations were found in the liver. While Cu, Pb and Cd concentrations were highest in fish tissues collected in August 2000, the lowest concentrations of these metals were observed in fish tissues collected in May 2000. Pb had the highest level observed in fish tissues. According to the Turkish Food Codex Regulation's residue limits, the cadmium level determined in fish tissues was high (0.1 microg/g) and the lead level, especially in liver tissue, was high in August (1 microg/g), while other metals (Cu, Cr and Ni) were within the maximum residue limits.     

Heavy metals in vegetables collected from production and market sites of a tropical urban area of India

Vegetables (Beta vulgaris L., Abelmoschus esculentus L. and Brassica oleracea L.) from the production and market sites of India were tested for Cu, Cd, Zn and Pb. At market sites, the mean concentration of Cu in cauliflower, and of Zn and Cd in both palak and cauliflower had exceeded the PFA standard. Zn at the production sites also exceeded the PFA standard in cauliflower. Cd concentration in vegetables tested from both production and market sites was many folds higher than the EU standard. In contrast, Pb in vegetables tested from both production and market sites was below the PFA limit, but was considerably higher than the current EU and WHO standards. Heavy metals accumulation in vegetables tested are higher at market sites than those at the crop production sites. The contributions of these vegetables to dietary intake of Cu, Zn, Cd and Pb were 13%, 1%, 47% and 9% of provisional tolerable daily intake, respectively. The study concludes that the transportation and marketing systems of vegetables play a significant role in elevating the contaminant levels of heavy metals which may pose a threat to the quality of the vegetables with consequences for the health of the consumers of locally produced foodstuffs.     

Potential risk assessment of trace metals accumulation in food,water and edible tissue of rainbow trout (Oncorhynchus mykiss) farmed in Haraz River,northern Iran

This study focuses on the extent of Zn, Cu, Ni, Cd and Pb bioaccumulation in water, fish feed and the muscles of 40 rainbow trout (Oncorhynchus mykiss) from four farmsalong Haraz River, Mazandaran Province, north of Iran. The dependence of bioaccumulation with food chain and environmental heavy metals concentration was specifically addressed. The potential human health risks due to consumption of rainbow trout have been assessed by estimated daily intake (EDI) and target hazard quotient (THQ) of aforementioned metals. The detected concentration ranges of the elements in the muscles, reported as μg.g^?1?dry weight, were as following: Zn (13.92–15.92), Cu (0.54–0.74), Ni (0.12–0.26), Cd (0.008–0.01) and Pb (0.25–0.57). The rank order of the levels of the heavy metals was: in edible tissue Zn?>?Cu?>?Pb?>?Ni?>?Cd; in water Pb?>?Zn?>?Cu?>?Ni?>?Cd; in fish feed Pb?>?Zn?>?Ni?>?Cu?>?Cd. In general, the concentrations of all target metals were positively correlated with fish feed contents, whereas negative correlations were observed between the metal concentrations and water. Risk assessments suggested that there isn’t potential ecological and human health risk.     

Uptake of aluminum, cadmium, copper, lead, and zinc by human scalp hair and elution of the adsorbed metals

Uptake of aluminum (Al), cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) from aqueous solutions by human scalp hair (water/hair = 100:1) has been studied in the concentration range 0-50 mg/L. Hair metal levels were determined by a wet digestion procedure and atomic absorption spectrometry. Under conditions used, uptake followed a sigmoid concentration-response relationship. The order of binding capacity of hair to the metals was as follows: Al greater than Cd greater than Cu greater than Pb greater than Zn. Using logit transformation 50% saturation was evaluated at the following metal concentrations (hair metal concentration of saturation is given in parenthesis): 0.34 mg/L for Al (0.154 mg/g); 1.82 mg/L for Cd (0.363 mg/g); 2.21 mg/L for Cu (0.651 mg/g); 2.52 mg/L for Pb (0.986 mg/g); 23.84 mg/L for Zn (1.616 mg/g). Percentage elution of trace metals from hair after treatment with metal-enriched solutions by five different procedures ranged from 14.5 to 46.5% for Al, from 11.1 to 28.9% for Zn, from 11.5 to 28.4% for Pb, from 8.9 to 13.6% for Cd, and from 0.1 to 11.8% for Cu. In addition, trace element concentrations were measured in tap water samples and shampoos.     

Heavy metal concentration in muscle of pike (Esox lucius Linnaeus, 1758) from Anzali international wetland,southwest of the Caspian Sea and their consumption risk assessment

This study evaluated the concentrations of nine heavy metals in muscle specimens of pike (Esox lucius Linnaeus, 1758) from four sites of southwest of the Caspian Sea: Shijan, Abkenar, Hendakhale and Siakeshim. The potential human health risks due to consumption of pike have been assessed by estimated average daily intake (EDI) and target hazard quotient (THQ) of metals. In particular, Cu, Zn, Cd, Pb, Hg, As, Ni, Co and Mn were quantified in the edible tissue of specimens by AAS determination. The average metal concentrations of Cu, Zn, Cd, Pb, Hg, As, Ni, Co and Mn measured in this study were 1.12?±?0.264, 5.37?±?0.702, 0.058?±?0.023, 0.20?±?0.035, 0.005?±?0.002, 0.17?±?0.047, 0.33?±?0.062, 0.28?±?0.034 and 0.20?±?0.035?μg/g w wt, respectively. Our results demonstrate the consumption of muscle of pike for adult and children as less than 1, hence residents of these regions will not be exposed to significant health risks.     

Heavy metal (Pb,Cu, Zn,and Cd) concentrations in the water and muscle of common carp (Cyprinus carpio) fish and associated non-carcinogenic risk assessment: Alagol wetland in the Golestan,Iran

Short- and long-term exposure to heavy metals can be dangerous for human health. One of the main routes of exposure to heavy metals is intake of seafood such as fish. In this study, lead (Pb), copper (Cu), zinc (Zn), and cadmium (Cd) concentration in the water and muscle of C. Carpio fish was measured and non-carcinogenic risk of these heavy metals was estimated. The mean (range) concentrations of Cu, Zn, Pb, and Cd were 7.92?±?7.99 (1.22–39.43?mg/kg), 120.90?±?106.25 (1.15–477?mg/kg), 5.84?±?5.22 (ND-21.86?mg/kg), and 0.027?±?0.043 (ND-0.14). Except Cd, the concentrations of Cu, Zn, and Pb were significantly more than Food and Agricultural Organization United Nations (FAOUN) maximum guidelines (p??Cu?>?Pb?>?Cd in the water and muscle tissue of C. carpio fish. Lowest and highest target hazard quotient (THQ) for adults was related to Cd (0.005) and Pb (0.252) and for children, Cd (0.003) and Pb (0.168), respectively. The rank order of THQ for adults and children are Pb?>?Zn?>?Cu?>?Cd. Since THQ and hazard index (HI) for both adults and children were significantly lower than 1 (p?C. Carpio fish consumption.     

Evaluation of trace metals in tobacco of local and imported cigarette brands used in Pakistan by spectrophotometer through microwave digestion

Uncontrolled exposure of active and passive smokers to trace metals causes increase in health risks. The primary objective of this study was to determine whether local and imported cigarette brands used in Pakistan, have elevated levels of metals or not. Six metals manganese (Mn), cobalt (Co), copper (Cu), cadmium (Cd), lead (Pb) and zinc (Zn) were determined in tobacco of twenty cigarette brands (local and imported) used in Pakistan by flame atomic absorption Spectrophotometry. To overcome contamination chances and for complete digestion of analytes a microwave digester was used. The analytical results showed highest concentration of Mn (84.78 microg/g dry weight), Cd (0.525 microg/g dry weight) and Zn (14.34 microg/g dry weight) metals in imported brands in relation to counterparts from the local brands. Certain elevated levels were observed for Co (3.344 microg/g dry weight), Pb (14.16 microg/g dry weight) and Cu (7.889 microg/g dry weight) metals in local brands. The inter-metal relationships in the tobacco of local and imported cigarette brands showed some integrated variation in the selected metal levels. In view of health risk associated with the above metals, there should be a strict quality control over monitoring of heavy metals during growing, processing and smoking of tobacco. Therefore, it is prudent to minimize exposure to toxic substances whenever possible because smoking and exposure to cigarette smoke is a confounder to be taken into account when carrying out epidemiological studies on human exposure to metals.     

Estimation of the dietary intake of cadmium, lead, mercury, and arsenic by the population of Santiago (Chile) using a Total Diet Study.

Dietary intake of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) by the population of Santiago (Chile) was determined using a Total Diet Study in the market basket modality. After conducting a survey of the foods consumed in the last 24 h, the most consumed food products were included in the basket. Subsequently, they were cooked or prepared according to typical Chilean procedures and grouped into 17 food categories according to their chemical characteristics. The fish and shellfish group had the highest contents of As (1351 ng/g wet weight, ww), Cd (277 ng/g ww), and Hg (48 ng/g ww), while the sugar group had the highest content of Pb (251 ng/g ww). For a person with a body weight of 68 kg, the dietary intakes of As (77 microg/day), Cd (20 microg/day), Hg (5 microg/day), and Pb (206 microg/day) are lower than the provisional tolerable weekly intake values established by the FAO/WHO. Consequently, the total intakes of As, Cd, Hg, and Pb in Santiago (Chile) are within the limits estimated as safe.     

Potential health risks due to heavy metal uptake via consumption of Thunnus thynnus from the northern Levantine Sea

The potential human health risks of copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) in Thunnus thynnus from the northern Levantine Sea were assessed. The mean concentrations (mg/kg) of metals were found as 0.819 for Cu, 8.344 for Zn, 2.102 for As, 0.002 for Cd, 0.001 for Hg and 0.115 for Pb. Even though these values were below the permitted levels, 11% of the samples contained Pb above the limits. Estimated weekly intakes were conspicuously lower than the PTWI values. The target hazard quotients (THQs) of each metal and total THQ of combined metals remained well below 1, showing no public health risk for an average consumer.     

Contribution of fish consumption to heavy metals exposure in women of childbearing age from a Mediterranean country (Spain).

The concentrations of cadmium (Cd), lead (Pb) and mercury (Hg) were determined in samples from sword-fish (Xiphias gladius, n=37) and louvar (Luvarus imperialis, n=17) taken in an official surveillance programme in Madrid (Spain). The levels of heavy metals were measured by atomic absorption spectrophotometry (hydride generator for Hg and flame atomic absorption for Cd and Pb) after digestion of the samples (microwave digestion for Hg and drying chamber for Cd and Pb). Pb contamination was negligible in both species. Cd was detected in 89.19% of the samples from sword-fish and 52.94% from louver; 17.65% of louvar and none from sword-fish being higher than maximum residue limits (MRL). However, around 90% of louvar samples and around 35% of sword-fish portions exceeded MRL for Hg; around 30% of louvar samples having levels even higher than 1 microg/g. The consumption of one serving of 150 g either of louvar or sword-fish would not be relevant for Cd and Pb provisional tolerable weekly intake (PTWI) of these elements for women in childbearing age, but it would largely exceed the tolerable values for Hg.     

Comparison of Eleven Heavy Metals in Moringa Oleifera Lam. Products

Eleven heavy metals in various products of Moringa oleifera were analyzed to determine eleven heavy metals (Al, As, Cd, Cr, Cu, Fe, Pb, Mn, Hg, Ni, and Zn) using Inductively Coupled Plasma-Mass Spectrometry. The products of M. oleifera were purchased in Nakhon Pathom, Thailand. All products were digested with nitric acid solution before determining the concentrations of heavy metals. The recoveries of all heavy metals were found to be in the range of 99.89-103.05%. Several criteria such as linearity, limits of detection, limits of quantification, specificity, precision under repeatability conditions and intermediate precision reproducibility were evaluated. Results indicate that this method could be used in the laboratory for determination of eleven heavy metals in M. oleifera products with acceptable analytical performance. The results of analysis showed that the highest concentrations of As, Cr, Hg, and Mn were found in tea leaves while the highest concentrations of Al, Cd, Cu, Fe, Ni, Pb, and Zn were found in leaf capsules. Continuous monitoring of heavy metals in M. oleifera products is crucial for consumer health.     

Urinary metallothionein and tissue metal levels of rats injected with cadmium, mercury, lead, copper or zinc

Since Cd exposure results in a dose dependent increase in metallothionein level in urine, the present investigation was conducted to examine whether exposure to other divalent cations would also cause an elevation in urinary metallothionein. Female Sprague-Dawley rats were injected subcutaneously with either saline, 5 mumol/kg/day of CdCl2, HgCl2, Pb(C2H3O2)2, CuSO4 or ZnCl2 for 5 days. Significant increases in hepatic Cu levels in rats treated with not only Cu, but also Zn, Cd, or Hg, and in hepatic Zn levels in rats treated with Zn or Cd were noted. Similarly, renal Cu and Zn levels were elevated significantly in all groups except the Pb-injected group. These increases in tissue metal levels were presumably due to induction of metallothionein. The urinary metallothionein level in control rats on day 0, determined by radioimmunoassay, was 0.85 +/- 0.17 mg/g creatinine. There was no significant change in urinary metallothionein level in rats given up to 5 injections of saline or Pb. Hg-injected rats showed 25-fold increase in urinary metallothionein after 5 injections, whereas Cd-injected rats had 9-fold increase. There were also 2- and 3-fold increases of urinary metallothionein by Cu and Zn treatments for 5 days, respectively. Thus, urinary metallothionein levels were elevated in response to Cd, Hg, Cu and Zn, but not Pb; Hg had the most profound effect at equimolar doses.     

Bioaccumulation of trace metals in the Antarctic amphipod Paramoera walkeri (Stebbing, 1906): comparison of two-compartment and hyperbolic toxicokinetic models

Bioaccumulation of Cd, Pb, Cu and Zn in the Antarctic gammaridean amphipod Paramoera walkeri (Stebbing, 1906) was investigated at Casey station (Australian Antarctic Territory). The main goals were to provide information on accumulation strategies of the organisms tested and to verify toxicokinetic models as a predictive tool. The organisms accumulated metals upon exposure and it was possible to estimate significant model parameters of two-compartment and hyperbolic models. These models were successfully verified in a second toxicokinetic study. However, the application of hyperbolic models appears to be more promising as a predictive tool for metals in amphipods compared to compartment models, which have failed to adequately predict metal accumulation in experiments with increasing external exposures in previous studies. The following kinetic bioconcentration factors (BCFs) for the theoretical equilibrium were determined: 150-630 (Cd), 1600-7000 (Pb), 1700-3800 (Cu) and 670-2400 (Zn). We find decreasing BCFs with increasing external metal dosing but similar results for treatments with and without natural UV radiation and for the combined effect of different exposure regimes (single versus multiple metal exposure) and/or the amphipod collective involved (Beall versus Denison Island). A tentative estimation showed the following sequence of sensitivity of P. walkeri to an increase of soluble metal exposure: 0.2-3.0 microg Cd l(-1), 0.12-0.25 microg Pb l(-1), 0.9-3.0 microg Cu l(-1) and 9-26 microg Zn l(-1). Thus, the amphipod investigated proved to be more sensitive as biomonitor compared to gammarids from German coastal waters (with the exception of Cd) and to copepods from the Weddell Sea inferred from literature data.     

Renal and hepatic accumulation of cadmium and lead in the expression of CYP4F2 and CYP2E1

The present study examined accumulation of the metal toxins cadmium (Cd) and lead (Pb) in relation to the abundance of cytochrome P450 4F2 (CYP4F2), CYP2E1 and concentrations of zinc and copper in liver and kidney samples using immunoblotting coupled with metal analysis. The post mortem liver and kidney cortex samples were from 23 males and 8 females aged 3-89 years. All were Caucasians who had not been exposed to metals in the workplace. Average kidney cortex Cd load of 17.4 microg/g w.w. was 17 times greater than average liver Cd load (1.1 microg/g w.w.). In contrast, average kidney cortex Pb load of 0.09 microg/g w.w. was two times lower than liver Pb load of 0.19 microg/g w.w. Average Zn and Cu concentrations in the kidney cortex samples were 67% and 33% lower than those in the liver. Liver and kidney Cd loads, but not liver or kidney Pb loads, correlated positively with donors' age. After controlling for liver Cd load, an inverse correlation was seen between Zn and age (partial r=-0.39, P=0.02), suggesting reduction in liver Zn levels in old age. Liver CYP2E1 protein abundance correlated with age-adjusted Cd load (partial r=0.37, P=0.02) whereas kidney CYP4F2 protein abundance showed a positive correlation with age-adjusted Cd loads (partial r=0.40, P=0.02). These findings suggest that Cd may be an inducer of renal CYP4F2 and hepatic CYP2E1 and that increased renal CYP4F2 expression may implicate in Cd-linked renal tubular dysfunction and high blood pressure, involving CYP4F2-dependent arachidonic acid metabolism.     

维药刺叶锦鸡儿重金属及有害元素形态分布和健康风险评价

目的测定刺叶锦鸡儿中重金属及有害元素铜、镉、铅、砷和汞(Cu、Cd、Pb、As和Hg)的含量,了解其形态分布特征。方法采用欧洲共同体参考物机构(European Community Bureau of Reference,BCR)对不同形态的重金属及有害元素进行提取,使用原子吸收分光光度法测定重金属及有害元素的含量。依据联合国粮农组织/世界卫生组织(FAO/WHO)提出的健康人群金属的最大日允许摄入量(MTDI)及周耐受摄入量(PTWI)进行健康风险评估。结果刺叶锦鸡儿中Cu、Cd、Pb、As和Hg的含量分别为28.511 6,0.031 0,1.310 7,0.164 6和0.187 9mg·kg-1。其中,Cu、Pb和As以残渣态为主;Cd以可还原态所占比例最高;Hg以酸溶态的含量最高。健康风险初步评价结果表明,成人每日摄入刺叶锦鸡儿15~50g,从刺叶锦鸡儿中摄入的Cu、Cd、Pb、As和Hg含量分别为427.67~1 425.58,0.47~1.55,19.66~65.53,2.47~8.23和2.82~9.39μg,分别占每日允许摄入量(ADI)的21.39%~71.29%,0.82%~2.19%,9.17%~30.58%,1.96%~6.53%和6.62%~22.04%,均低于FAO/WHO所推荐的每人每日允许摄入量。结论日摄入刺叶锦鸡儿15~50g,对人体健康风险影响较小。     

Market basket survey for some heavy metals in Egyptian fruits and vegetables.

A market basket survey was carried out with the aim to assess the levels of lead (Pb), cadmium (Cd), copper (Cu) and zinc (Zn) in various fruits and vegetables sold in Egyptian markets. Atomic absorption spectrometry was used to estimate and evaluate the levels of these metals. The results of this survey showed that the average concentrations detected were ranged from 0.01 to 0.87, 0.01 to 0.15, 0.83 to 18.3 and 1.36 to 20.9 mg/kg for Pb, Cd, Cu and Zn, respectively. The highest mean levels of Pb, Cd, Cu and Zn were detected in strawberries, cucumber, date and spinach, respectively. The levels of the metals compare with those reported for similar fruits and vegetables from some other parts of the world. The daily intakes of Pb, Cd, Cu and Zn through fruits and vegetables have also been estimated. They are found to be below the recommended tolerable levels proposed by [Joint FAO/WHO Expert Committee on Food Additives 1999. Summary and conclusions. In: 53rd Meeting, Rome, June 1-10, 1999] and may not constitute a health hazards for consumers.