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1.
Heavy metal uptake from greenhouse border soils for edible vegetables   总被引:2,自引:0,他引:2  
Six essential elements, cadmium and lead were determined in some horticultural species cultivated in greenhouse borders by atomic absorption spectrophotometry to evaluate the contribution of these vegetables to the daily intake of cadmium and lead in Spain. The existence of significant differences ( P <0.001) in the levels of metallic concentration found among the vegetable species has been proved, and the greater capacity of concentration of heavy metals, except copper, in green beans was observed. No statistically significant correlation ( P > 0.05) between the concentration of the soil and that of corresponding vegetable species was found. The heavy metal uptake from soil to plants is a function of the physical and chemical nature of the soil and is altered by innumerable environmental and human factors. If the mean levels of cadmium and lead (0.029 mg kg?1 and 0.221 mg kg?1 respectively) are taken into account, the daily intake contribution of these metals will be 1.4 μg day?1 for cadmium and 11 μg day?1 for lead.  相似文献   

2.
Heavy metal contamination in the food chain is of serious concern due to the potential risks involved. The results of this study revealed the presence of maximum concentration of heavy metals in the canal followed by sewerage and tube well water. Similarly, the vegetables and respective soils irrigated with canal water were found to have higher heavy metal contamination followed by sewerage- and tube-well-watered samples. However, the heavy metal content of vegetables under study was below the limits as set by FAO/WHO, except for lead in canal-water-irrigated spinach (0.59 mg kg?1), radish pods (0.44 mg kg?1) and bitter gourd (0.33 mg kg?1). Estimated daily intakes of heavy metals by the consumption of selected vegetables were found to be well below the maximum limits. However, a complete estimation of daily intake requires the inclusion of other dietary and non-dietary exposure sources of heavy metals.  相似文献   

3.
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   

4.
In this study, 144 raw milk samples were analysed for heavy metal contamination derived from emissions from industrial operations in Tekkekoy, Samsun, Turkey. Cu, Fe, Zn, Cr, Ni, Cd, As and Pb levels in samples were determined by inductively coupled plasma mass spectrometry (ICP‐MS). The average amounts of copper, chromium, iron, zinc, nickel, cadmium, arsenic and lead were determined as 1.130, 0.441, 12.920, 0.032, 0.483, 0.006, 0.003 and 0.004 mg/kg, respectively. It was determined that the summer period has the highest levels for copper, lead and cadmium. The highest contents of arsenic and copper were found at the two industrial regions that were close to Black Sea, described as ‘1st’ and ‘2nd’ region. Whereas the 3rd and 4th regions that were far from an industrial zone and also from the Black Sea, nickel, lead and chromium had the highest levels.  相似文献   

5.
目的 对不同重金属胁迫蔬菜产生金属硫蛋白(金属硫组氨酸三甲基内盐)进行同源性检测。方法 用Cd-MT免疫家兔产生IgG后, 用不同浓度硫酸铜、乙酸铅、氯化钴、氯化汞等重金属胁迫萝卜幼苗、油白菜和油麦菜诱导产生金属硫蛋白, 通过免疫印迹检测其同源性。结果 Cd-MT与重金属胁迫三种蔬菜所产生的金属硫蛋白具有同源性; 不同浓度的重金属对幼苗中MTs表达量有影响。结论 Cd-MT诱导家兔产生的IgG可用于农产品中重金属污染的检测。  相似文献   

6.
BACKGROUND: Human exposure to heavy metals is attributed to consumption of food crops grown in polluted soil environment. The objective of our study was to assess the health risks of heavy metals in edible seeds of crops grown in sewage‐irrigated soils located in the Langfang of Hebei province, China. Here, heavy metal contents in soils and plants were determined using an internal standard and high‐resolution inductively coupled plasma mass spectrometry. RESULTS: There was a relative buildup of heavy metals in sewage‐irrigated soils in the study area; in particular, all Cr and partial Zn and Cu showed higher concentrations than the limits proposed by the World Health Organization, European Union (EU) and UK. Heavy metal concentrations in edible seeds of plants grown in sewage‐irrigated soils partly exceeded the permissible limits set by the EU, UK and the State Environmental Protection Administration in China. With the exception of Cu, health risk index values of each heavy metal investigated by intake of the edible seeds were less than 1. Here, a health risk index of < 1 is considered safe for human consumption. CONCLUSION: The study indicated that there was a relative absence of health risks associated with the ingestion of sewage‐irrigated edible seeds. Copyright © 2009 Society of Chemical Industry  相似文献   

7.
BACKGROUND: Rize in Turkey was contaminated by the Chernobyl accident in 1986. A comprehensive study was planned and carried out to determine the radioactivity levels and heavy metal concentrations in four food categories collected in Rize in 2008, 2009 and 2010. RESULTS: Tomato showed the highest concentration of 238U, at 9.43 ± 0.128 Bq kg?1, whereas the lowest concentration of 0.20 ± 0.02 Bq kg?1 was measured in aubergine samples. The highest concentration of 232Th was measured at 3.22 ± 0.29 Bq kg?1 in grape samples. 40K was found to contribute the highest activity in all the food samples. The highest activity concentration of 137Cs was 10.20 ± 4.19 Bq kg?1, for parsley. The average contribution range of each of the heavy metals to the dietary intake was 0.13–9.14, 0.27–34.63, 0.05–3.62, 0.11–14.97, 0.78–8.51 and 0.01–1.57 mg, respectively, for Mn, Fe, Cu, Zn, Ni and As. CONCLUSION: The range of radioactivity levels in food samples of the present study is of no risk to public health. Heavy metal concentrations of Mn, Fe, Cu, Zn, Ni and As obtained were far below the established values by FAO/WHO limits. Copyright © 2011 Society of Chemical Industry  相似文献   

8.
目的 考察4个牧场的生鲜牛乳的重金属污染情况,评估鲜牛乳原料的安全性.方法 采用国家标准检测方法对4个牧区的生牛乳中重金属铬、铅、汞以及金属砷进行检测,其中使用石墨炉原子吸收光谱法测定铅和铬的含量,使用氢化物发生原子荧光光谱法测定总砷含量,使用原子荧光光谱分析法测定总汞的含量.结果 铬含量最高的为DR牧场(0.052 ...  相似文献   

9.
The impact of water availability on Vitis vinifera L cv Tempranillo grape yields and juice composition over a 3 year period was studied. Grape juice composition during the different stages of berry growth was compared. The analytical data collected were used to investigate the relationships between some of the different components studied in these berries during the ripening period. The object was to determine whether the relationships could be used to derive mathematical equations for use as indicators of the changes taking place in the different parameters considered and thus of the optimum time for harvesting the grapes for a given wine‐making process. Very similar equations were derived for this grape variety irrespective of the culture conditions (use or non‐use of irrigation) or the different ripening conditions employed. A high degree of correlation between some of the components considered was observed. In any case, cause‐and‐effect relationships could only be established for certain of the parameter pairs considered (total acidity/pH, pH/potassium, °Brix/glucose + fructose, total acidity/tartaric acid and malic acid). For other parameter pairs (berry weight/°Brix, °Brix/pH, °Brix/total acidity) the relationship found was attributable to accumulation and breakdown processes which took place concurrently or overlapped in time. In two cases only there was uncertainty as to whether the relationship observed between the parameters was a cause‐and‐effect relationship or whether the parameters were so closely related that they acted as mutually limiting factors (°Brix/proline, °Brix/total anthocyanins). © 2002 Society of Chemical Industry  相似文献   

10.
目的了解不同加工工艺的蜂胶加工品对去除原胶中有害重金属的效果。方法采用微波消解,石墨炉原子吸收光谱法和氢化物发生原子荧光光谱法测定两种蜂胶加工品中的4种有害重金属(铅、镉、总汞、总砷)含量并测定3个浓度的加标回收率。结果 4种元素标准曲线相关系数均在0.999以上,加标回收率乙醇萃取法在83.8%~114.2%,超临界萃取法在72.6%~108.5%之间,采用超临界萃取法加工蜂胶中铅、镉、总砷含量明显低于采用乙醇萃取法加工蜂胶,总汞含量在两种加工工艺中均未检出。结论在有害重金属含量的食品安全性上超临界萃取法的加工工艺优于乙醇萃取法。  相似文献   

11.
The concentrations of heavy metals (Cd, Co, Cu, Fe, Mn, Ni, Pb, Zn) were measured in muscle, gill and liver of two fish species (Leuciscus cephalus and Lepomis gibbosus) caught from Saricay, South-West Anatolia. Levels of metals varied depending on different tissues in species. The mean concentrations (μg g−1 wet weight) of heavy metals in tissues of Leucis cephalus were as follows: Cd: 0.010–0.084, Co: nd–0.131, Cu: 0.193–2.611, Fe: 4.240–172.000, Mn: 0.112–24.230, Pb: 0.068–0.874, Zn: 6.350–28.550, and in tissues of Lepomis gibbosus were as follows; Cd: 0.008–0.082, Co: nd–0.233, Cu: 0.065–4.360, Fe: 11.200–125.000, Mn: nd–12.434, Pb: 0.070–0.920, Zn: 6.540–16.064. Ni was not determined in all organs studied.  相似文献   

12.
分别采集不同设备和工艺加工生产线所加工的薏仁谷精米和碎米,检测As、Pb、Cd、Hg、Cu、Zn和Mn含量,评估其污染程度和膳食暴露风险。结果表明,在污染程度评估中,A生产线所产精米Zn含量和碎米Mn含量均在需警戒范围,精米Mn含量表明有轻度污染,各被测元素含量在B生产线所产精米和碎米中均在良好范围,且所受Mn污染明显小于A生产线所产精米和碎米;在健康风险评估中,A生产线和B生产线所产精米出现了Cu膳食暴露风险,A生产线所产精米还出现了Mn膳食暴露风险。综合评价,B生产线比A生产线所产精米和碎米的重金属污染及膳食暴露风险更小。  相似文献   

13.
目的分析刺参中低浓度氨基脲的残留分布特征,明确不同来源引起的低浓度氨基脲的变化趋势。方法采用超高效液相色谱-串联质谱法对不同来源氨基脲在刺参(Apostichopusjaponicus)体内的富集和消除规律进行研究。结果非呋喃西林源氨基脲, 1 d后氨基脲在刺参体壁的含量为0.57μg/kg,之后含量逐渐上升,到3d时含量度达到最大值1.00μg/kg。富集实验共持续3d,按天计算平均富集速率,分别为0.57、0.24、0.19μg/(kg·d),第140 d时体壁未检出,平均消除速率为0.0073μg/(kg·d);呋喃西林源氨基脲, 1 d后体壁的含量为0.52μg/kg,之后含量逐渐上升,到3 d时,含量达到最大1.00μg/kg。富集实验共持续3 d,按天计算平均富集速率,分别为0.52、0.26、0.22μg/(kg·d),第160 d时体壁未检出,平均消除速率为0.0064μg/(kg·d)。跟踪监测至180 d时,非呋喃西林源氨基脲和呋喃西林源氨基脲在刺参体壁内均未检出,半衰期分别为1045.7 h和1224.2 h,呋喃西林源大于非呋喃西林源。内脏的富集和消除速率相对较快,但内脏中氨基脲残留量大于体壁,所以降至未检出所需时间更长。结论在投喂过呋喃西林或暴露于一定浓度氨基脲的刺参,需经较长时间净化后才能降至未检出。  相似文献   

14.
The salt uptake homogeneity is crucial in assuring quality in dry-cured hams. The aim of this study was to evaluate the effect of the water contents at the lean surface before salting and of the temperature during salting on the salt uptake. Pieces of loin stored at 3 °C for 3 days before salting absorbed less salt through a surface that has been dried during storage. A group of raw hams were subjected to different pre-salting storage times (0, 3 and 6 days) and another group subjected to different set room temperatures during salting (− 1.0, 0.5 and 4.0 °C). The duration of storage before salting and the temperature during salting had a negative and a positive effect on the average salt absorption, respectively. The most important effects appeared after 6 days of storage and at 4 °C. No significant differences in salt uptake homogeneity were found between storage times and between salting temperatures.  相似文献   

15.
16.
Heavy metals are an important group of chemical contaminants and food is the major vehicle for entry into the system. Fish constitute a major source of heavy metals in food. Concentration of heavy metals in commercially important species of fish, shellfish and fish products from fish markets in and around the Cochin area was evaluated using an atomic absorption spectrometer. The concentration ranges of Cd, Pb, Hg, Cr, As, Zn, Cu, Co, Mn, Ni, and Se in the samples were <0.07–1, <0.07–1.32, <0.05–2.31, <0.05 to 3.65, <0.1–4.14, 0.6 to 165, 0.15 to 24, <0.02 to 0.85, <0.08 to 9.2, <0.032–1.38 and; <0.03–1.35 mg/kg, respectively. The present study showed that different metals were present in the samples at different levels but within the maximum residual levels prescribed by the EU and USFDA and the fish and shellfish from these areas, in general, are safe for human consumption.  相似文献   

17.
In this work, three heavy metals (HMs) cadmium, lead, and zinc were determined in 16 newly breaded varieties of sunflower seed oil, using atomic absorption spectrometry, prior to use of microwave-assisted acid digestion method (MWD). The accuracy of the proposed method was studied by standard addition method and values obtained by conventional wet acid digestion methods (CAM) on same samples. The detection limit obtained from the standard addition curve was 0.327, 3.38, 10.0 ng/ml for Cd, Pb, and Zn, respectively, with high percentage recoveries. Multivariate statistical techniques (cluster and principal component analysis) were applied to modeling classes of different varieties of sunflower seed oils grown in same agricultural plot, on the basis of the analytical data of HMs. The results obtained providing sufficient information on tolerable limit of all three HMs by different varieties of sunflower oil to grow safely.  相似文献   

18.
Curry leaves (Murraya koenigii), collected from 19 different Indian states, were analyzed for six minor (Ca, Cl, K, Mg, Na and P) and 20 trace (As, Ba, Br, Ce, Co, Cr, Cs, Cu, Fe, Hg, La, Mn, Rb, Sb, Sc, Se, Sr, Th, V and Zn) elements by instrumental neutron activation analysis (INAA). In addition, Ni, Cd and Pb were determined by atomic absorption spectrophotometry (AAS). Most elements vary over a wide range, depending on geo-environmental factors and local soil characteristics. Fe, Mn, Na, K, Rb, Se and P vary by a factor of 3–5 whereas Br, Cs, Sc, Th and Zn vary by an order of magnitude. Leaves collected from the southern zone were enriched in K, Mg, Mn, Cl and P but depleted in Se. However, leaves from the northern zone were particularly enriched in Ca whereas those from the western zone were enriched in Zn. Concentrations of most elements from the eastern zone were on par with the mean values. Cr, Fe, Cu, V and Zn are known to play an important role in the maintenance of normoglycemia by activating β-cells of pancreas. Percent contributions of diabetically important elements from curry leaves were 1–2% of daily dietary intake (DDI) but are likely to be in bioavailable form thus making them effective for treatment of diabetes. Rb and Cs are linearly correlated (r = 0.93) as their salts enhance the absorption of insulin in the lower respiratory tract by breakdown of glucose. Inorganic elements may remain complexed with organic ligands.  相似文献   

19.
Relationships between the fresh mass of seed, skin (exocarp), and flesh (mesocarp) in six different berry size categories, were assessed on ripe fruit from Cabernet Sauvignon grapevines exposed to either High (H), Control (C) or Low (L) water status during post‐veraison berry growth in a vineyard. Berries harvested from each treatment were segregated into six mass categories in order to distinguish between changes in fresh mass components associated with general variation in berry size (on well‐watered grapevines), and those associated with berry size differences due to water stress. Berry fresh mass across all treatments ranged from about 0.4 to 2.0 g. Fresh mass components for both H and C berries comprised approximately 5% seed, 15% skin, and 80% flesh, regardless of variation in berry size, although there was some increase in seed mass relative to whole‐berry fresh mass in larger berries. Berry growth (as inferred from fresh mass at harvest) was much less sensitive to water deficit than published reports for grapevine shoot growth. Midday leaf water potentials around –1.20 MPa (Control) were not sufficient to inhibit berry growth. However, midday water potentials around –1.50 MPa (Low water status) inhibited berry growth by 13–18% of that attained by grapevines grown at high water status (i.e. treatment H where midday leaf water potentials remained around –1.00 MPa). Inhibition of berry growth by water deficit was attributed almost exclusively to reduced growth of mesocarp tissues (for most berry size categories). Water deficit thus increased the proportion of whole‐berry fresh mass represented by seeds and skin (for most berry size categories). Changes in those proportions due to irrigation treatments exceeded differences associated with general (non‐stress) variation in whole‐berry fresh mass. Excluding adverse environmental impacts on whole‐berry fresh mass, our results point to a limited role for variation in berry size per se as a factor determining the solute concentration of juice or wine derived from different sized fruit. By implication, and for all categories of whole‐berry fresh mass represented here, late season water deficit can result in ripe fruit with more skin and seed tissues (relative to whole‐berry fresh mass) compared with well‐watered control fruit.  相似文献   

20.
A deep‐sea isolate of the psychrotolerant yeast Cryptococcus sp. (NIOCC#PY13) obtained from polymetallic nodule‐bearing sediments of the Central Indian Basin was examined for its capacity to grow in the presence of various concentrations of the heavy metal salts i.e., ZnSO4, CuSO4, Pb(CH3COO)2 and CdCl2. It demonstrated considerable growth in the presence of 100 mg/l concentrations of the above‐mentioned four heavy metal salts both at 30°C and 15°C. This strain tolerated comparatively higher levels of these four metal salts than other deep‐sea and terrestrial yeast isolates belonging to Cryptococcus, Rhodotorula, Rhodosporidium and Sporidiobolus spp. Optimum pH for growth of this isolate was in the range of 6–8 in the presence of heavy metal salts at these two temperatures. Scanning electron microscopic (SEM) studies exhibited altered cell surface morphology of the cells under the influence of heavy metals compared to that with control. The adsorption of heavy metals to the cells was demonstrated by FTIR and EDAX analysis. As evidenced by atomic absorption spectrophotometric (AAS) analysis, about 30–90% of the heavy metals were removed from the culture supernatant after 4 days of growth at 30°C. This deep‐sea yeast isolate appears to be a potential candidate for bioremediation of metal‐contaminated sites. Moreover, its metal tolerance properties provide a significant insight into its ecological role and adaptations to growth in such extreme conditions. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

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