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1.
Few studies have examined docosahexaenoic acid (DHA) in pregnant and lactating women in developing countries like China, where DHA-enriched supplements are increasingly popular. We aimed to assess the DHA status among Chinese pregnant and lactating women residing areas differing in the availability of aquatic products. In total, 1211 women in mid-pregnancy (17 ± 2 weeks), late pregnancy (39 ± 2 weeks), or lactation (42 ± 7 days) were enrolled from Weihai (coastland), Yueyang (lakeland), and Baotou (inland) city, with approximately 135 women in each participant group by region. DHA concentrations were measured using capillary gas chromatography, and are reported as weight percent of total fatty acids. Mean plasma DHA concentrations were higher in coastland (mid-pregnancy 3.19%, late pregnancy 2.54%, lactation 2.24%) and lakeland women (2.45%, 1.95%, 2.26%) than inland women (2.25%, 1.67%, 1.68%) (p values < 0.001). Similar differences were observed for erythrocyte DHA. We conclude that DHA concentrations of Chinese pregnant and lactating women are higher in coastland and lakeland regions than in inland areas. DHA status in the study population appears to be stronger than populations from other countries studied to date.  相似文献   

2.
北京市居民饮用水中16种金属元素暴露水平   总被引:1,自引:0,他引:1  
目的了解北京市居民饮用水中16种金属元素(铅Pb、镉Cd、铜Cu、锌Zn、铁Fe、锰Mn、镍Ni、银Ag、锑Sb、硒Se、铝Al、钡Ba、铍Be、铊Tl、钼Mo和钠Na)暴露水平。方法采用多阶段整群抽样设计,在北京市18个区县随机抽取5个区的270户,采用电感耦合等离子体质谱法,对枯水期、丰水期居民饮用水中16种金属指标进行监测。结果居民饮用水中16种元素的暴露水平由低到高可以分为3层:Ag、Cd、Sb、Be和Tl暴露水平为:未检出~0.083μg/L,Mo、Pb、Ni和Se暴露水平为:0.06~100μg/L,Cu、Al、Zn、Mn、Fe、Na和Ba暴露水平为:0.00036~6.579mg/L。统计表明,11种元素(Pb、Se、Mo、Cu、Zn、Mn、Ni、Al、Ba、Fe和Na)暴露水平枯水期明显高于丰水期(P<0.05),以《生活饮用水卫生标准》GB5749—2006中的标准值为评价标准,枯水期Na、Al、Mn、Zn、Fe、Ba、Pb、Se的合格率为87.4%~98.9%;丰水期Mn、Ni、Zn、Fe、Pb和Se的合格率为95.2%~99.6%,其他元素合格率为100%。来自市政水源的饮用水中8种元素(Pb、Cu、Zn、Mn、Al、Ba、Fe和Na)的暴露水平明显低于来自自备水源的饮用水(P<0.05)。结论北京市居民饮用水中16种金属元素总体处于低暴露水平,大部分指标市政供水好于自备水源供水。  相似文献   

3.
目的了解孕妇和新生儿脐血中铅、镉、砷、汞、锰和硒元素的含量,分析其胎盘通透性。方法于2010年9月至2013年12月在山东省渤海莱州湾某二甲医院,招募符合标准的孕妇及其新生儿为研究对象。共纳入773对孕妇及其新生儿。根据所测定元素的种类,分为汞测定组(595对)、铅测定组(534对)和镉、砷、锰、硒测定组(244对)。问卷调查获得孕妇及新生儿的人口学信息,检测母血和脐血中铅、镉、砷、汞、锰和硒的浓度,并计算各元素的胎盘通透性(某元素脐血浓度/母血浓度);采用Spearman秩相关分析母血和脐血中各元素的相关性。结果773名母亲年龄为(28.34±4.50)岁,孕周为(39.47±1.39)周;773名新生儿出生体重为(3419.47±497.39)g。母血和脐血中铅、镉、砷、汞、锰和硒各元素的中位数浓度分别为31.12和30.02、1.19和0.47、8.05和6.03、0.69和1.26、100.70和105.55、127.25和115.00μg/L。铅、镉、砷、汞、锰和硒的胎盘通透性分别为0.98、0.41、0.73、1.73、0.96和0.91。铅、镉、汞、锰和硒在母血和脐血中均呈正相关,Spearman相关系数分别为0.397、0.298、0.698、0.555和0.285(P值均<0.001)。结论铅、镉、砷、汞、锰和硒元素在母血和脐血中均普遍检出;汞的胎盘通透性较高。  相似文献   

4.
Although some studies suggested a link between exposure to trace elements and development of multiple sclerosis (MS), clear information on their role in the aetiology of MS is still lacking. In this study the concentrations of Al, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn, Sr, Tl, V, W, Zn and Zr were determined in the blood of 60 patients with MS and 60 controls. Quantifications were performed by inductively coupled plasma (ICP) atomic emission spectrometry and sector field ICP mass spectrometry. When the two groups were compared, an increased level of Co, Cu and Ni and a decrement of Be, Fe, Hg, Mg, Mo, Pb and Zn in blood of patients were observed. In addition, the discriminant analysis pointed out that Cu, Be, Hg, Co and Mo were able to discriminate between MS patients and controls (92.5% of cases correctly classified).  相似文献   

5.
Analytical methods using sector field ICP-MS and ICP-AES were developed for the determination of Al, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn, Sr, Tl, V, W, Zn and Zr in cerebrospinal fluid, urine, serum and blood. Sample treatment procedures merging high sample throughput, simplicity and low contamination risk were set up. Method performances were evaluated in terms of detection limits, accuracy and precision. The limits were below 0.05 ng ml(-1) for all the elements, except for Al (all matrices), Hg (blood), Pb (blood) and Sn (serum and blood). The accuracy varied from 86% to 110% and the precision was always below 6%.  相似文献   

6.
Samples of yard waste compost and sewage sludge compost were analyzed for toxic and nutrient elements and PCBs to assess variations in their concentrations as a function of the time of delivery of the initial organic material to the same composting site. In general, the variations in composition found were remarkably small. Generally, the samples of sludge compost were higher in Ca, Cd, Cu, Fe, Hg, Mo, Na, P, Pb, S, Se, Zn, and PCBs than those of the yard waste compost. The latter was higher in Cr, Ni, K, Mg, and Si. Possible factors affecting compost composition are discussed.  相似文献   

7.
Reference values for 26 elements, namely Al, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn, Sr, Tl, V, W, Zn and Zr are proposed in serum and blood of 110 healthy adults of the urban area of Rome. They were included in the study on the basis of strict criteria of eligibility and exclusion. With the exception of Ba, Bi, Co, Cr, Ni, Sb, Sn Tl in serum, and Bi, Hg, Si, V and W in whole blood, experimental data for each all the other analytes were found to approach a normal distribution. The estimated 5-95% references ranges (in ng ml(-1)) were reported. For several elements the reference ranges observed overlapped information available in the literature. Gender, age, body mass index, smoking habits and alcohol consume were used as grouping variables. Mutual associations were observed for several elements, as follows: Be, Ca, Co, Cr, Cu, Li, Mo, Pb and Zn with sex; Ca, Pb and Si with age (< and > 45 years); Co, Cr, Mo, Sb and Tl with body mass index; Cd and Pb with smoking habit; Cr and Pb with alcohol consume.  相似文献   

8.
Twenty-six metals and the oxidative status in 71 patients affected by Parkinson's disease and 44 healthy individuals were compared in order to identify potential biomarkers of the disease. In the patients, the following significant imbalances were found (p < or = 0.05): i) in serum, an increment of Ca, Mg, Ni, Si and V, and a decrement of Cd, Co, Fe, Li, Sn, Zn and Zr; ii) in blood, raised levels of Co, Li, Ni and Si and decreased of Al, Be, Ca, Cd, Fe, Mg, Mo, Sn, Zn and Zr; iii) increased formation of oxidant species and lowered anti-oxidant capacity (p < or = 0.001 for both). Barium, Bi, Cr, Cu, Hg, Mn, Pb, Sb, Sr, Tl and W did not change with the disease. The best discriminating variables between patients and controls were Cd, Co, Fe, Ni and Si in serum (91.2% of cases correctly classified), and Al, Cd, Co, Fe, Mo and Si in blood (98.2% of cases properly classified).  相似文献   

9.
目的 本研究主要观察孕妇及胎儿体内铅、砷、锅、锰和锌元素的水平并对其影响因素进行探讨.方法 2006年9月至2007年4月,共采集130对母血及脐血,同时测量新生儿的生长发育指标.采用电感耦合等离子质谱法测定母血和脐血中的铅、砷、镉、锰和锌元素的含量,并对其相关关系及影响因素进行了探讨.结果 母血的铅、砷、镉、锰和锌含量中位数(μg/L)分别为64.32,3.81,0.84,54.26和6312.50.脐血的铅、砷、镉、锰和锌含量中位数(μg/L)分别为35.72,2.84,0.32,78.99和2250.镉元素(r=0.341,P=0.000)和砷元素(r=0.552,P=0.000)在母血与脐血之间呈相关性.职业有害因素及居室装修是血砷、血锌的影响因素.使用多重线性回归发现孕妇体重、职业有害因素及孕妇血压对血锰、锌、砷和镉浓度在考虑其他掺杂影响因素后有统计学意义.结论 环境因素和母体因素可能影响母血及脐血中元素含量;本研究中重金属元素含量虽低于正常参考值上限水平,但与发达国家相比,含量仍偏高,不容忽视.重金属的孕期暴露对胚胎发育的影响值得予以进一步关注.  相似文献   

10.
白族药野坝子的微量元素分析   总被引:1,自引:0,他引:1  
用原子吸收分光光度法 (AAS)测定白族药野坝子的 Cu、Zn、Fe、Mn、Ca、Se、Ge、Ni、Co、Cd、Sr、Ba、Li、Mo、Si、Pb、Cr、Al的含量 ,发现野坝子中除含人体必需的多种微量元素外 ,还富含 Cu、Zn、Fe、Mn、Se,这为进一步研究和综合开发利用这一民族药提供了依据  相似文献   

11.
Fourth instars larvae of freshwater midge Chironomus javanus (Diptera, Chironomidae) were exposed for a 4-day period in laboratory conditions to a range of copper (Cu), cadmium (Cd), zinc (Zn), lead (Pb), nickel (Ni), iron (Fe), aluminium (Al) and manganese (Mn) concentrations. Mortality was assessed and median lethal concentrations (LC(50)) were calculated. LC(50) increased with the decrease in mean exposure times, for all metals. LC(50)s for 96 hours for Cu, Cd, Zn, Pb, Ni, Fe, Al and Mn were 0.17, 0.06, 5.57, 0.72, 5.32, 0.62, 1.43 and 5.27 mg/L, respectively. Metals bioconcentration in C. javanus increases with exposure to increasing concentrations and Cd was the most toxic to C. javanus, followed by Cu, Fe, Pb, Al, Mn, Zn and Ni (Cd > Cu > Fe > Pb > Al > Mn > Zn > Ni). Comparison of LC(50) values for metals for this species with those for other freshwater midges reveals that C. javanus is equally or more sensitive to metals than most other tested dipteran.  相似文献   

12.
ICP-OES法分析18种中药材中11种元素及其分布特征   总被引:2,自引:0,他引:2  
目的:采用电感耦合等离子原子发射光谱法研究18种中药材中11种无机元素的含量,寻找不同中药材中元素分布特性和相关性,为控制中药材中的有关元素含量、保障中药材质量和安全提供依据。方法:收集18种不同产地的中药材,经微波消解后,电感耦合等离子体原子发射光谱法(ICP-OES)同时测定铅、镉、钴、铬、镍、铜、锰、铁、锌、钡和铝元素含量,并应用SPSS 15.0软件对测定结果进行统计分析。结果:建立的ICP-OES法线性相关系数大于0.9999,相对标准偏差小于10%,加标回收率在80%~120%之间。药材中铝、铬、钴、镉、铜、铁、锰、镍、锌元素间存在相关性;铝、铬、铁、锰、镍、锌元素在部分药材品种中具有一定规律性和特异性;铝、钡、铁元素在某些药材中存在含量异常现象。结论:ICP-OES法简便快速、准确、可靠,是中药材中部分元素测定的一种较好方法,为从安全性和有效性方面控制药材质量提供了一种解决方案。  相似文献   

13.
Twenty-six chemical elements and oxidative status were determined in serum of 12 patients with first demyelinating episode and brain magnetic resonance imaging compatible with the disease at different time points. Quantifications of Al, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, Hg, Li, Mg, Mn, Mo, Ni, Pb, Sb, Si, Sn, Sr, V, Tl, W, Zn and Zr, as well as of serum oxidative status and antioxidant capacity were carried out. The results were compared with values obtained from healthy subjects living in the same geographic area. Concentration variability, expressed as coefficient of variation (CV), was evaluated over a six months longitudinal follow-up. The CV was higher for Li and Pb, while showed minimal variation for Ca, Cu, Mg and Zn--elements strictly body regulated. Significant difference (p < or = 0.05) in mean concentrations of Ba, Ca, Cd, Cr, Li, Mn, Mo, Ni, Sb, Si, Sn and Zr between patients at time 0 and controls was also found.  相似文献   

14.
The concentrations and distribution of metals (Fe, Mn, Zn, Cu, Pb, Ni, Co, As, Hg, and Cd) in an earthworm,Pheretima hilgendorfi, and their variations with growth were investigated. Higher concentrations of the metals were found in the pre-clitellar regions of the earthworm compared with the post-clitellar ones; Cd, Cu, and Hg were relatively high in the gut wall. The body concentration of Pb and Hg decreased with increased body length (age) and weight, while the opposite was found for Cd and As. The accumulation of Fe, Mn, Zn, Cu, Ni, and Co in the earthworm depends primarily on the metabolic turnover, whereas the accumulation of Pb, Hg, Cd and As, is dependent upon the age or exposure time. Small earthworms showed faster uptake and excretion rates of Pb and Hg than the large ones, and the biological half-lives of Pb and Hg were relatively short compared with those of Cd and As. The large earthworms exhibited a decrease of Hg in the bodies, probably due to excretion of Hgvia spawning. Based upon these results, the sizes and parts of the earthworm suitable for purposes of research are discussed.  相似文献   

15.
Concentrations of 23 elements (Ca, K, Mg, P, Al, Cu, Fe, Mn, Mo, Na, Ni, Zn, Ag, Ba, Be, Cd, Co, Cr, Pb, Sb, Th, Tl, and V) in leaf and twig samples of a fir (Abies fabri) and a rhododendron (Rhododendron williamsianum) collected along an altitudinal gradient on Mount Gongga, China, are reported in the present study. Most of the macronutrients (K and P), micronutrients (Fe, Zn, Cu, Na, Ni, Mo, and Al), and trace elements (Pb, Tl, Ag, Cd, Ba, Co, V, Be, and Cr) are significantly enriched in fir when compared to rhododendron; however, Ca, Mg, Mn, Ba, and Cd are more enriched in rhododendron than in fir. Most of the elements in both plants are more significantly enriched in twigs than in leaves. The relationship between element concentration in plants and altitudinal gradient is nonlinear. Altitudes of 3,200 and 3,400 m are turning points for fir and rhododendron growth, respectively. Concentrations of all trace elements in the two plants along the altitudinal gradient are well below the toxic level in plants. No known industrial sources of the elements investigated exist in the Mount Gongga area, China. Element concentrations in the present study are higher than those found in mosses collected from the same area, indicating that the area is not contaminated. The element concentrations that we observed in plant samples were due to soil uptake. The pronounced differences between the two species are due to the different uptake characteristics of fir and rhododendron.  相似文献   

16.
We collected bullfrog (Rana catesbeiana) larvae from a coal combustion waste settling basin to investigate the effects of developmental stage and timing of metamorphosis on concentrations of a series of trace elements in bullfrog tissues. Bullfrogs at four stages of development (from no hind limbs to recently metamorphosed juveniles) and bullfrogs that metamorphosed in the fall or overwintered in the contaminated basin and metamorphosed in the spring were analyzed for whole-body concentrations of Al, V, Cr, Ni, Cu, As, Pb, Cd, Zn, Ag, Sr, and Se. After the effects of dry mass were removed, tissue concentrations of six elements (Al, V, Cr, Ni, Cu, As, and Pb) decreased from the late larval stage through metamorphosis. Decreases in concentrations through metamorphosis ranged from 40% for Cu to 97% for Al. Tissue concentrations of these elements were also similar or higher in spring; Al and Cr concentrations were 34 and 90% higher in the spring, respectively, whereas As, Ni, Cu, and Pb concentrations were <10% higher. Concentrations of Cd, Se, and Ag varied among seasons but not among stages; Cd and Ag concentrations were 40 and 62% lower, respectively, and Se concentrations were 21% higher in spring. Concentrations of Zn varied only among stages; concentrations decreased gradually through late larval stage and then increased through metamorphosis. Concentrations of Sr varied among stages, but this variation was dependent on the season. Concentrations of Sr were higher in larval stages during the spring, but because concentrations of Sr increased 122% through metamorphosis in the fall and only 22% in the spring, concentrations were higher in fall metamorphs when compared with spring metamorphs. Our results indicate that metamorphosis and season of metamorphosis affects trace element concentrations in bullfrogs and may have important implications for the health of juveniles and the transfer of pollutants from the aquatic to the terrestrial environment.  相似文献   

17.
Data are presented for 13 trace metals (Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, and Pb) in 38 bivalve mussels Anodonta woodiana from four separate sites (Huzhou, Dapu, Sansandao, and Manshan) around the Taihu Lake of China. All elemental concentrations generally ranked in decreasing order, Mn > Fe > Zn > As ≈ Cu ≈ Cd ≈ Se > Pb > Mo ≈ Ag, except that Cr, Co, and Ni were not detected. Anodonta woodiana was able to bioaccumulate essential Mn and toxic Cd to the extremely high level of 19,240 and 53 mg/kg dry weight, respectively. Geographical differences in the concentrations of trace elements were usually significant between sampling sites except for As and Pb, and the mussels from Sanshandao site had mostly accumulated or were contaminated with essential and toxic elements. The residue level of Cd in A. woodiana from the Sanshandao and Manshan sites appeared to be even higher than those of the essential elements Cu and Se, and exceeded the corresponding maximum residue limits of China. The present study provides the most recent information on trace element bioaccumulation or contamination in Taihu Lake and, further, suggests that A. woodiana can be used as a suitable bioindicator for inland water environmental monitoring.  相似文献   

18.
目的探讨燃煤污染型氟中毒病区氟斑牙流行程度与饮用水源化学元素组成的空间分布特征及其关联性。方法 2022年基于贵州省CDC氟斑牙流行程度的调查资料, 在典型燃煤污染型氟中毒区域采集274份原有地表饮用水源, 测定水中氟、钙、镁、铝、钛、铬、锰、铁、镍、铜、锌、砷、硒、钼、镉、钡、铅17种元素的含量;应用Moran’’sI指数、Getis-OrdGi*热点分析饮用水中化学元素的全局空间自相关性以及各元素在局部区域上聚集程度, 并与该区域氟斑牙流行程度进行关联分析。结果除铜、锌、镉元素全局空间自相关Moran’’sI指数为负值外, 其他元素均为正值;氟、钙、铝、钛、砷、钼、镉、铜元素在东南部低海拔地区呈高值聚集;镁、钡、铅、铬、锰、铁元素主要在中部海拔地势过渡区聚集, 锌、硒元素则主要聚集在西南部高海拔地区;水源中锌、硒元素与氟斑牙流行程度呈显著正相关(P<0.05), 而氟、镁、铝、钛、砷、钼、镉、钡、铅元素与之呈显著负相关(P<0.05)。氟、钙、铝、钛、砷、钼元素在东南部地区及锰、铁、钡元素在中部地区呈高-高聚集, 为疾病高发的热点聚集区, 而氟、铝、锰、钼、镉、钡元素在...  相似文献   

19.
Sediment and American oyster (Crassostrea virginica) collected from nine selected marsh/estuarine ecosystems in Savannah, Georgia were analyzed for elements such as Al, As, B, Cd, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Si, and Zn. Sediments were extracted by ammonium acetate (NH4OAc), Mehlich-3 (M-3), and water procedures, whereas an acid digestion procedure was adopted for oyster tissue. Concentrations of elements were higher in M-3 extractions followed by NH4OAc and water extraction procedures. Calcium and Mg was greater in sediments by any of the extractions, whereas other elements differed depending upon the extraction procedures. There were no significant spatial variations (p < 0.05) of any of elements analyzed except Mn, in NH4OAc/water extraction procedure and Fe and Al by water extraction procedure. Contamination of Al, B, Cd, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Si, and Zn in oyster tissue ranged from 399 to 1460, 231 to 254, <1.5 to 2.9, <1.5 to 8.0, 67 to 121, 232 to 1357, 17 to 54, <0.5 to 0.64, <1.5 to 2.5, <1.5 to 4.0, 241 to 381, and 978 to 2428 μg/g dry weight (dw), respectively. Greatly elevated concentrations of elements such as P, Ca, Mg, K, and S were noticed in oyster tissue. The concentration range of Hg and As in sediment was 1.2–1.9 and 11–55 μg/g dw, respectively. The concentration range of Hg and As in oyster tissue was 130–908 and 200–912 ng/g dw, respectively. With the exception of As and Hg, other elements are several orders of magnitude greater in oyster tissue. There is no significant (p < 0.05) contamination variation in target analyses between the nine selected sites. Concentrations of heavy metals in sediment and oyster were either comparable or lower than those of other countries. Greater biota-sediment accumulation factor was noticed for P and Zn. Concentrations of Hg and P in oyster tissue were higher than the threshold limit for human consumption. Overall, the baseline data can be used for regular ecological monitoring, considering the domestic and industrial growth around this important marsh/estuarine ecosystem.  相似文献   

20.
目的探讨银川市大气PM_(2.5)中金属元素来源及各来源所占比例,为金属元素污染控制提供科学依据。方法在银川市城区设置2个监测点,2015年每月定期采集大气PM_(2.5)样品,共采集样品164份,分析锑(Sb)、铝(Al)、砷(As)、镉(Cd)、铬(Cr)、汞(Hg)、铅(Pb)、锰(Mn)、镍(Ni)、硒(Se)、铊(Tl)11种金属元素含量及来源。结果 PM_(2.5)质量浓度及部分金属元素含量具有明显的季节变化特征,夏秋低、冬春高。PM_(2.5)中金属元素平均质量浓度顺序:AlPbMnAsTbCdCrSeTlNiHg,环境空气中Pb年均浓度和季平均浓度均未超标。Pb、Tl、Cd、Mn、Se、As主要来源为人为源,主要受到交通源、工业源及燃烧源等人为污染影响。结论银川市大气PM_(2.5)重金属元素的污染特征和来源有其自身的地域性特征。PM_(2.5)质量浓度及金属元素含量受供暖期影响,主要来源于人为污染。  相似文献   

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