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1.
The critical Cd exposure level to induce tubular dysfunctions is a focus of public concern among general populations in Japan.
To answer this question, one group each (about 1000 adult women/area) in nonpolluted areas with high (Area H) and low Cd exposure
(Area L) was obtained, and 742 strictly age-matched pairs of never-smoking adult women were selected for comparison. Cd, α 1-MG (microglobulin) and β 2-MG in urine were taken as markers of exposure and tubular dysfunction, respectively. Geometric mean Cd levels as corrected
for creatinine (Cd cr) was greater than three times higher in Area H (2.8 μg/g cr) than in Area L (0.8 μg/g cr). Nevertheless, β 2-MG cr did not differ between the two areas (125 μg/g cr for Area H vs 118 μg/g cr for Area L). α 1-MG cr was only marginally higher in Area H (2.8 mg/g cr) than in Area L (2.1 mg/g cr), with no biomedical significance. Results
were essentially the same when analyses were conducted with noncorrected observed values or values corrected for a specific
gravity. Thus, the effects of Cd exposure in Area H on renal tubular function should be essentially nil. 相似文献
2.
Larvae of Galleria mellonella L. (Lepidoptera, Pyralidae) were exposed to Pb (4, 43, 430 μg Pb/g food dw) and Cd (4, 20, 40 μg Cd/g food dw) applied singly
and in combination. Metal transfer of Pb and Cd was investigated from food to larvae and successive stages of G. mellonella and also to the pupal parasitoid Pimpla turionellae L. (Hymenoptera, Ichneumonidae). Larvae/food concentration factors (CFs) were highest in controls (Cd 5.25, Pb 3.07) and
ranged from 0.19 to 0.92 for Cd and from 0.18 to 0.83 for Pb in contaminated groups; in general, the CFs decreased with an
increasing contamination level in food. G. mellonella eliminated most of its larval metal load before pupation (metal concentration in larvae ς> pupae). Although pupae were only
moderately contaminated (0.11–1.61 μg Cd/g dw), concentrations in P. turionellae ranged from 0.5 to 6.8 μg Cd/g dw. Again, CFs (parasitoid/pupa) decreased with enhanced levels of metal in the host pupae
(Cd 3.07–14.05, Pb 0.0–2.47). The CFs calculated for both species were lower at combined contamination compared to single
application. G. mellonella can be classified as a ‘deconcentrator’ (CF<1) along with other lepidopteran species, whereas P. turionellae is apparently a ‘macroconcentrator’ (CF>2). 相似文献
3.
The main purpose of this study was to establish the temporal trend in the daily dietary intake of arsenic (As), cadmium (Cd),
mercury (Hg), and lead (Pb) by the population of Catalonia, Spain. Concentrations of these elements were determined in samples
of a number of food items widely consumed in that country. The dietary intake of As, Cd, Hg, and Pb was then estimated for
various age–gender groups of population: children, adolescents, adults, and seniors. In the present study, the dietary intakes
of As, inorganic As, Cd, Hg, methylmercury, and Pb were 328.37, 16.22, 19.47, 11.39, 10.25, and 101.47 μg/day, respectively,
while in a previous (2006) survey, the dietary intakes of As, inorganic As, Cd, Hg, methylmercury, and Pb were 261.01, 33.17,
9.80, 12.61, 11.35, and 45.13 μg/day, respectively. The estimated intakes of Cd, Hg, and Pb are still notably lower than the
respective PTWIs, while that of inorganic As is also lower than its BMDL 01. In summary, the results of this study indicate that, currently, the dietary intakes of As, Cd, Hg, and Pb should not mean
additional health risks for the consumers. 相似文献
4.
Trace elements including Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were analyzed in the scalp hair
samples of women with malignant breast lesions, women with benign breast lesions, and healthy donors using atomic absorption
spectrophotometric method. In the scalp hair of malignant-tumor patients, the highest average concentration was shown by Ca
(1,187 μg/g), followed by Na (655 μg/g), Mg (478 μg/g), Zn (391 μg/g), Sr (152 μg/g), Fe (114 μg/g), and K (89.8), while in
the case of benign-tumor patients, the average estimated element levels were 1,522, 1,093, 572, 457, 217, 80.4, and 74.7 μg/g,
respectively. Most of the elements exhibited non-normal distribution evidenced by large spread, standard error, and skewness
values. Mean concentrations of Ca (634 μg/g), Zn (206 μg/g), Mg (162 μg/g), Fe (129 μg/g), and Na (82.1 μg/g) were noteworthy
in the scalp hair of healthy women. Average levels of Na, Sr, K, Cd, Co, Pb, Mg, Ca, Zn, Ni, Sb, and Mn were revealed to be
significantly higher in the hair of malignant and benign patients compared to the healthy women; however, Fe, Cu, Al, and
Cr were not significantly different in the scalp hair of the three groups. The quartile distributions of Ca, Cd, Co, Cr, K,
Mg, Mn, Na, Ni, Pb, Sb, and Sr revealed maximum spread in the scalp hair of malignant and benign groups; nevertheless, Al,
Cu, Fe, and Zn exhibited almost comparable quartile levels in the three groups. Strong correlation coefficients were found
between Fe and Cd, Al and Na, Mn and Sr, Co and Cr, Cd and Cr, Pb and K, Pb and Mn, Cu and Na, and Al and Fe in the scalp
hair of malignant-tumor patients, while Fe and K, Cd and Co, Na and Co, and Cr and Pb showed strong correlations in the scalp
hair of benign-tumor patients, both of which were significantly different compared with the healthy subjects. Multivariate
cluster analysis also revealed divergent clustering of the elements in the scalp hair of malignant and benign patients in
comparison with the healthy women. 相似文献
5.
We examined how the influence of smoking on blood and urinary cadmium (Cd) concentrations was modified by the level of environmental
Cd. We measured blood and urinary Cd concentrations of 1134 men over 50 yr of age in three areas in Japan that were exposed
to different levels of environmental Cd. Analysis of variance was used to compare Cd concentrations in blood and urine of
smokers with those of nonsmokers living in the three areas. Correlation coefficients between the number of cigarets smoked
per day or smoking indices (the number of cigarets smoked per day multiplied by the number of years smoked) and blood and
urinary Cd concentrations were calculated. No significant difference in Cd concentrations between smokers and nonsmokers was
observed in areas where the average Cd concentration in blood was over approx 2.4 ng/g, 2.0 μg/L in urine, and 2.3 μg/g creatinine
in urine, respectively. Therefore, it was suggested that an influence of smoking on blood and urinary Cd concentrations was
not observed in areas exposed to relatively high levels of environmental Cd. 相似文献
6.
The concentrations of As, Be, Cd, Cr, Hg, Mn, Ni, Pb, Sn, Tl, and V were determined in hair of 96 school children and in blood
of 144 adults living in the vicinity of a hazardous waste incinerator (HWI) (Constantí, Tarragona County, Catalonia, NE Spain).
The results were compared with those obtained in previous (1998 and 2002) surveys performed in the same area. Data were analyzed
in terms of age, sex, and specific place of residence. Current mean concentrations in hair ranged between not detected (ND)
(As, Be, and Tl) and 1.31 μg/g for Cr. In blood, Be, Hg, Mn, Sn, and Tl levels were under the respective detection limits.
The mean blood concentrations of the remaining elements ranged from 0.34 μg/dL for Cd, to 2.40 μg/dL for Pb. Significant differences
in hair and blood in relation to gender were only noted for Pb in blood. In general terms, metal concentrations in hair and
blood from subjects living in Tarragona County are lower than most levels reported for other countries in recent years. 相似文献
7.
In situ immobilization and phytoextraction techniques have been used for remediation of Pb and Cd polluted soils. Three rates (0.25, 0.5 and 1.0%) of seven immobilizing agents (cement, slag, phosphate rock, bitumen, Fe- and Al-gels, and δ-MnO 2) were tested on three soils containing various levels of Pb (48–192.0 ug/g) and Cd (0.75–3.45 ug/g). All immobilizing agents reduced the plant available Pb and Cd as extracted by DTPA (diethylenetriaminepentaacetic acid). The effectiveness of the various agents in immobilizing Pb and Cd followed the descending order: bitumen > cement > slag > Fe-gel > Al-gel > phosphate rock > δ -MnO 2. Cement and phosphate rock fixed Pb and Cd mainly in the carbonate form, whereas the slag, bitumen, Fe-gel, Al-gel and δ -MnO 2 fixed the metals mainly in the oxide form. The results of pot experiment proved the high ability of barnyard grass (Echinnochloa stagninum) to accumulate elevated amounts of Pb and Cd (ranging from 291–2421 and 6.1–45.9 ug metal/g dry matter, respectively). These amounts are higher than those reported for hyperaccumulators, particularly for Pb. The amounts of Pb and Cd removed by barnyard grass represent, on average, 46 and 72% of their initial total contents in the soils, respectively. These results proved that, without any other soil treatments, barnyard grass is highly efficient in removing considerable amounts of Pb and Cd from polluted soil within a reasonably short period of time. Therefore, use of barnyard grass for the phytoremediation of Pb and Cd polluted soils is feasible and recommended as an environmentally safe and cheap method. The most significant finding of this study is to name the barnyard grass as an efficient lead accumulator plant. 相似文献
8.
Postpartum scalp hair samples from 82 term-pregnancy mother/neonate pairs were analyzed for their concentration of zinc (Zn),
copper (Cu), cadmium (Cd), and lead (Pb), using inductively coupled plasma-mass spectrometry. Maternal and neonatal Zn concentrations
had geometric means (and 99% confidence intervals) of 122.5 μg/g (117.9–131.5 μg/g) and 146.9 μg (141.5–156.7 μg/g) respectively.
Corresponding Cu values were 18.4 μg/g (17.6–23.8 μg/g) and 6.7 μg/g (6.3–7.6 μg/g). Those of Cd were 0.49 μg/g (0.47–0.69
μg/g) in the mothers and 0.57 μg/g (0.55–0.86 μg/g) in the neonates. For Pb, they were 7.95 μg/g (7.60–9.32 μg/g) and 4.56
μg/g (4.39–5.56 μg/g). Cigaret smoking, despite its relatively low prevalence (19.5%), was associated with lower Zn and higher
Cd and Pb concentrations and in lower Zn/Cd and Zn/Pb molar concentration ratios. Smoking also altered interelemental relationships,
particularly those of Zn with Cd and Pb and those between Cd and Pb. Smoking frequency appeared to show negative dose-response
effects on maternal and neonatal Zn concentrations, Zn/Pb molar concentration ratios, and birth weight. Mothers with a history
of oral contraceptive (OC) usage had significantly higher Cu concentrations and lower Zn/Cu molar concentration ratios than
nonusers, with the highest Cu concentrations and lowest Zn/Cu values being associated with third-generation OCs. No similar
effects were elicited in the respective neonatal Cu concentrations. Neither alcohol consumption nor prenatal supplementation
with iron and/or folic acid had discernible effects on the maternal or neonatal elemental concentrations. The data from this
study suggest that in a given population of term-pregnancy mothers and neonates, significant interindividual variations in
hair trace element concentrations can occur, irrespective of commonality of general environment, and that lifestyle factors,
including cigaret smoking and OC usage history, can be significant contributory factors to such variations. The data are discussed
in relation to the effects of smoking-associated exposure to Cd and Pb exposure on Zn availability for placental transfer,
as well as on the quantitative maternal Zn supply levels to the fetus resulting from the known tendency of smokers to have
lower dietary intakes of Zn. The higher Cu concentrations in OC users are discussed in relation to altered Cu metabolism,
characterized by increased synthesis of the Cu-binding protein, ceruloplasmin, as an acute-phase antioxidant response to altered
lipid profile and increased lipid oxidation. 相似文献
9.
The effects of Cu, Cd, and Pb toxicity on photosynthesis in cucumber leaves ( Cucumis sativus L.) were studied by the measurements of gas exchange characteristics, chlorophyll (Chl) fluorescence parameters, and Chl content. Concentrations of metals in sequence of 20 M Cu, 20 and 50 M Cd, and 1 000 M Pb decreased the plant dry mass to 50–60 % after 10 d of treatment whereas 50 M of Cu decreased it to 30 %. The content of Cd in leaves of plants treated with 50 M Cd was three times higher than the contents of Cu and Pb after plant treatment with 50 M Cu or 1 000 M Pb. Hence Cd was transported to leaves much better than Cu and Pb. Nevertheless, the net photosynthetic rate and stomatal conductance in leaves treated with 50 M Cu or Cd were similarly reduced. Thus, Cu was more toxic than Cd and Pb for photosynthesis in cucumber leaves. None of the investigated metals decreased internal CO 2 concentrations. Also the effect of metals on potential efficiency of photosystem 2, PS2 (F v/F m) was negligible. The metal dependent reduction of PS2 quantum efficiency ( PS2) after plant adaptation in actinic irradiation was more noticeable. This could imply that reduced demand for ATP and NADPH in a dark phase of photosynthesis caused a down-regulation of PS2 photochemistry. Furthermore, in leaves of metal-treated plants the decrease in water percentage as well as lower contents of Chl and Fe were observed. Thus photosynthesis is not the main limiting factor for cucumber growth under Cu, Cd, or Pb stress.This revised version was published online in March 2005 with corrections to the page numbers. 相似文献
10.
The concentrations of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) were determined in samples of food items widely
consumed by the population of Catalonia, Spain. All samples were randomly acquired in 12 cities of Catalonia between March
and June of 2006 and analyzed by inductively coupled plasma mass spectrometry. The dietary intake of these elements was estimated
for various age–gender groups of population: children, adolescents, adults, and seniors. In order to determine the temporal
trend on the dietary exposure to As, Cd, Hg, and Pb, the current results were compared with those of a previous survey (2000).
In the present market basket study, for a standard male adult of 70-kg body weight living in Catalonia, the dietary intakes
of As, Cd, Hg, and Pb were 261.01, 9.80, 12.61, and 45.13 μg/day, respectively, while in the 2000 survey, these intakes were
223.59, 15.73, 21.22, and 28.37 μg/day, for As, Cd, Hg, and Pb, respectively. For As, the only food groups currently contributing
with measurable amounts to intake of total As were fish and shellfish and cereals, while for Cd the highest contribution to
total intake corresponded to pulses, tubers, and cereals. For Hg, the contribution was only due to fish and shellfish, while
cereals were the group with the highest contribution to total Pb intake. The estimated intakes of As, Cd, Hg, and Pb are notably
lower than the respective provisional tolerable weekly intakes, which indicate that these intakes should not mean additional
health risks for the consumers. 相似文献
11.
Recent publications in Japan suggest that Cd in river beds and locally harvested rice tend to be higher in seven prefectures
in the north-eastern part on the coast of the Sea of Japan (the high-Cd zone). The present study was initiated to investigate
the current level of exposure to Cd and possible health effects among local populations in the zone. Thus, levels of Cd and
three tubular dysfunction markers [i.e., α
1-MG, β
2-MG, and N-acetyl-β- d-glucosaminidase (NAG)] were examined in urine of local residents (700 and 704 adult women, respectively) in two prefectures
(prefecture 1 and prefecture 7), which were located in the north-east (prefecture 1) and south-west ends (prefecture 7) of
the high-Cd zone. Urinary Cd levels [e.g., 0.99 and 0.78 μg/l as geometric mean (GM) for observed (non-corrected) values,
respectively] in prefecture 1 and prefecture 7 were comparable to the levels in other parts of Japan (All Japan-A; 0.99 μg/l).
Correspondingly, GM values for α
1-MG (2.29 and 1.99 mg/l vs. 2.17 mg/l for All Japan-A) and for β
2-MG (87 and 80 μg/l vs. 99 μg/l for All Japan-A) were not elevated, and NAG also stayed unchanged (2.89 and 2.87 units/l for
prefecture 1 and prefecture 7, respectively). Evaluation in combination with the findings in other five prefectures in the
zone suggests that Cd exposure is equal to the national average both in prefecture 1 and in prefecture 7, whereas Cd exposure
appeared to be elevated in the central part of the zone. The observation appears to be on line with geographical location
of the two prefectures that they are on the two ends of the zone of high natural Cd background. 相似文献
12.
This study was initiated to examine accumulation of cadmium (Cd) and other metals in kidney and liver in autopsy samples and
to compare the levels between those in an area with heavy Cd exposure and those in no-polluted areas in Japan. Data on Cd
and other metals in kidney (cortex and medulla) and liver in 95 cases (87 women and eight men; the exposed) in a Cd-polluted
area and 43 cases (21 women and 22 men; the controls) in non-polluted areas were cited from 15 previous publications to be
summarized together with six unpublished cases. Cd levels in kidney cortex and medulla were significantly lower in the exposed
(31.5 and 23.8 μg/g wet tissue as GM, respectively) than in the controls (82.7 and 36.4 μg/g, respectively), whereas Cd levels
in liver was higher in the exposed (60.2 μg/g) than in the controls (8.1 μg/g). Exposed women had lower Cd in the cortex (29.9 μg/g)
and medulla (22.7 μg/g) than exposed men (55.4 and 38.1 μg/g, respectively) as well as in cortex of control women (92.9 μg/g).
Comparison with worldwide data other than Japan for non-exposed populations [19.1, 9.3, and 1.3 μg/g in cortex, medulla, and
liver, respectively, as the inverse variance-weighted averages (IVWA) of GM values for each of 22 reports] suggests that the
levels for the non-exposed Japanese (123.3, 33.5, and 3.9 μg/g as IVWA) tended to be higher than the levels in other countries,
possibly reflecting high dietary Cd intake in the past. 相似文献
13.
Greenhouse hydroponic experiments were conducted using Cd-sensitive (Xiushui63) and tolerant (Bing97252) rice genotypes to
evaluate genotypic differences in response of photosynthesis and phytochelatins to Cd toxicity in the presence of exogenous
glutathione (GSH). Plant height, chlorophyll content, net photosynthetic rate (Pn), and biomass decreased in 5 and 50 μM Cd
treatments, and Cd-sensitive genotype showed more severe reduction than the tolerant one. Cadmium stress caused decrease in
maximal photochemical efficiency of PSII (Fv/Fm) and effective PSII quantum yield [Y(II)] and increase in quantum yield of
regulated energy dissipation [Y(NPQ)], with changes in Cd-sensitive genotype being more evident. Cadmium-induced phytochelatins
(PCs), GSH, and cysteine accumulation was observed in roots of both genotypes, with markedly higher level in PCs and GSH on
day 5 in Bing97252 compared with that measured in Xiushui63. Exogenous GSH significantly alleviated growth inhibition in Xiushui63
under 5 μM Cd and in both genotypes in 50 μM Cd. External GSH significantly increased chlorophyll content, Pn, Fv/Fm, and
Y(II) of plants exposed to Cd, but decreased Y(NPQ) and the coefficient of non-photochemical quenching (qN). GSH addition
significantly increased root GSH content in plants under Cd exposure (except day 5 of 50 μM Cd) and induced up-regulation
in PCs of 5 μM-Cd-treated Bing97252 throughout the 15-day and Xiushui63 of 5-day exposure. The results suggest that genotypic
difference in the tolerance to Cd stress was positively linked to the capacity in elevation of GSH and PCs, and that alleviation
of Cd toxicity by GSH is related to significant improvement in chlorophyll content, photosynthetic performance, and root GSH
levels. 相似文献
14.
This study was initiated to examine if variations in the concentrations of cadmium (Cd) and lead (Pb) in water environment
may affect metal levels in local foods and body burden of local residents in non-polluted areas in Japan. Two nationwide databases
have been made available on concentrations of Cd in locally harvested brown rice and of Cd and Pb in sediments in local river
beds. These data were combined with published data on metal concentrations in polished rice, food duplicates, and blood and
urine from the residents. Cd in river sediments correlated significantly with those in brown rice, food duplicates, blood,
and urine. Cd in food duplicates correlated with Cd in rice. In contrast, Pb concentrations in the river sediments either
did not correlate or correlated only weakly with Pb in biological materials or food duplicates. Possible implication of the
different behavior between Cd and Pb regarding the intensity of correlation was discussed with reference to the different
routes of exposure to the elements. In conclusions, the Cd body burden on local residents in Japan is significantly influenced
by Cd levels in water in the general environment, whereas water-borne Pb did not show clear correlation with the Pb body burden. 相似文献
15.
The aim of this study was to evaluate DNA damage and the capacity for DNA repair in children exposed to arsenic and lead.
During 2006, we studied a total of 85 healthy children (aged 4–11 years) who were residents of Villa de la Paz (community
A), Matehuala (community B), and Soledad de Graciano Sanchez (community C) in San Luis Potosi, Mexico. The quantification
of arsenic in urine (AsU) and lead in blood (PbB) was performed by atomic absorption spectrophotometry. The alkaline comet
assay was used to evaluate DNA damage and DNA repair. The highest levels of AsU and PbB in children were found in community
A (44.5 μg/g creatinine for arsenic and 11.4 μg/dL for lead), followed by community B (16.8 μg/g creatinine for arsenic and
7.3 μg/dL for lead) and finally by children living in community C (12.8 μg/g creatinine for arsenic and 5.3 μg/dL for lead).
When DNA damage was assessed, children living in community A had the highest DNA damage. Analysis of these same cells 1 h
after a challenge with H 2O 2 10 μM showed a dramatic increase in DNA damage in the cells of children living in community B and community C, but not in
the cells of children living in community A. Moreover, significantly higher levels of DNA damage were observed 3 h after the
challenge ended (repair period) in cells from individuals living in community A. Our results show that children exposed to
metals might be more susceptible to DNA alterations. 相似文献
16.
Diaphanosoma brachyurum (Cladocera: Sididae) is a common limnetic species in summer-temperate and tropical water bodies. Few studies have investigated
the sensitivity of D. brachyurum to toxic chemicals despite this species often being dominant in natural lakes and ponds. We performed acute toxicity tests
of three heavy metals, copper (Cu), zinc (Zn), and cadmium (Cd), to D. brachyurum. For D. brachyurum, the lethal concentration (LC) 50 values of Cu (24-h LC 50 = 16.4 μg/L, 48-h LC 50 = 10.4 μg/L) and Zn (24-h LC 50 = 253.4 μg/L, 48-h LC 50 = 174.1 μg/L) were lower than those for D. magna, one of the most used test organisms for toxic chemicals. On the other hand, for D. brachyurum the 24-h LC 50 of Cd (166.4 μg/L) was much greater than that for D. magna, and the 48-h LC 50 of Cd (69.8 μg/L) was comparable. Our results indicate that D. brachyurum may be more strongly influenced by Zn and Cu than is D. magna. It is likely that the summer plankton community in which Diaphanosoma species is dominant is more sensitive to heavy metals than a community in which Daphnia species are dominant. 相似文献
17.
Selenium (Se) reduces cadmium (Cd) toxicity in adult animals, but its effects in newborn animals are still unknown. This study
investigated Cd (as CdCl 2) absorption, distribution, and retention in suckling rats receiving oral Se supplementation (as Na 2SeO 3) in equimolar doses (8 μmol Cd and/or Se per kg b.w./day). Selenium was given either before and during Cd exposure (Se pre + Cd group; pre-treatment group) or only during Cd exposure (Se + Cd group). Rats were treated from postnatal day (PND) 6–14
as follows: controls (H 2O, PND 6–14), Se (PND 10–14), Cd (PND 10–14), Se pre + Cd (Se PND 6–14 + Cd PND 10–14) and Se + Cd (Se + Cd PND 10–14). Selenium supplementation, especially pre-treatment, decreased
Cd levels in the blood, brain, liver and kidney of suckling rats. Selenium levels in plasma, brain, and kidney also decreased.
These findings suggest that higher Se intake could efficiently reduce Cd retention during the suckling period. 相似文献
18.
Chemical fractionation methods may be capable of providing an inexpensive estimate of contaminant bioavailability and risk in smelter-contaminated soil. In this study, the relationship between metal fractionation and methods used to estimate bioavailability of these metal contaminants in soil was evaluated. The Potentially BioAvailable Sequential Extraction (PBASE) was used for Cd, Pb, and Zn fractionation in 12 soils contaminated from Pb and Zn mining and smelting activities. The PBASE procedure is a four-step sequential extraction: extraction 1 (E1) is 0.5 M Ca(NO 3) 2, E2 is 1.0 M NaOAc, E3 is 0.1 M Na 2EDTA, and E4 is 4 M HNO 3. Metal bioavailability for two human exposure pathways, plant uptake (phytoavailability) and incidental ingestion (gastrointestinal, Gl, availability), was estimated using a lettuce ( Lactuca sativa L.) bioassay and the in vitro-Gl Physiologically Based Extraction Test(PBET). Metal in the PBASE E1 fraction was correlated with lettuce Cd (P < 0.001) and Zn (P < 0.05) and was the best predictor of Cd and Zn phytoavailability. Only total metal content or the sum of all PBASE fractions, ΣE 1–4, were correlated (P < 0.001) with PBET gastric phase for Pb. The sum of the first two PBASE fractions, ΣE 1–2, was strongly correlated (P < 0.001) with Pb extracted by the PBET intestinal phase. The PBASE extraction method can provide information on Cd and Zn phytoavailability and Gl availability of Pb in smelter-contaminated soils. 相似文献
19.
Eighteen metals were estimated in the scalp hair samples from cancer patients ( n = 111) and normal donors ( n = 113). Nitric acid–perchloric acid wet digestion procedure was used for the quantification of the selected metals by flame
atomic absorption spectrophotometry. In the scalp hair of cancer patients, highest average levels were found for Ca (861 μg/g),
followed by Na (672 μg/g), Zn (411 μg/g), Mg (348 μg/g), Fe (154 μg/g), Sr (129 μg/g), and K (116 μg/g), whereas in comparison,
the dominant metals in the scalp hair of normal donors were Ca (568 μg/g), Zn (177 μg/g), Mg (154 μg/g), Fe (110 μg/g), and
Na (103 μg/g). The concentrations of Ca, Cd, Co, Cr, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were notably higher in the
hair of cancer patients as compared with normal donors, which may lead to a number of physiological disorders. Strong positive
correlations were found in Mn–Pb (0.83), Cd–Cr (0.82), Cd–Li (0.57), Fe–Pb (0.56), and Fe–Mn (0.55) in the hair of cancer
patients whereas Na–Cd, Li–Cr, Li–Co, Co–Cd, Li–Cd, Na–Co, Na–Li, Ca–Mg and Na–Cr exhibited strong relationships ( r > 0.50) in the hair of normal donors. Principal Component Analysis (PCA) of the data revealed seven PCs, both for cancer
patients and normal donors, but with significantly different loadings. Cluster Analysis (CA) was also used to support the
PCA results. The study evidenced significantly different pattern of metal distribution in the hair of cancer patients in comparison
with normal donors. The role of trace metals in carcinogenesis was also discussed. 相似文献
20.
To investigate the accumulation patterns of Cd and/or Pb in various body parts, organs and tissues of the Asian gypsy moth ( Lymantria dispar) larvae under Cd and/or Pb stress, Cd and Pb treated artificial diets were used to feed the larvae in the current study. These larval body parts/organs/tissues included the heads, integuments (body walls), alimentary canals, fat bodies and hemolymphs. Our results showed that under Cd and/or Pb stress, their accumulations in larval body parts/organs/tissues were significantly higher than those in the control, with the amounts of tested metals in the fat bodies and hemolymphs and alimentary canals being significantly higher than those in the heads and integuments. Under the single Cd (0, 7.5, 10.5 mg/kg) or Pb stress (0, 55, 90, 125 mg/kg), the accumulations of these heavy metals were positively correlated with their concentrations in diets. Under the combined stress (Cd × Pb), the Cd accumulation at the lower Pb concentrations was higher than that at higher Pb concentrations for the body parts/organs/tissues, similar effects of Cd concentrations on Pb accumulations were also recorded. These results clearly showed that Cd and/or Pb were accumulated in various body parts/organs/tissues at different levels under the heavy metal stress. And accumulations of Pb/Cd were positively correlated with their concentrations in the diets under the single stress. Under the combined stresses, Cd and Pb had synergistic effects at low concentrations whereas antagonistic effects at high concentrations. The accumulations of Cd and/or Pb in the gypsy moth larvae affects normal physiological and biochemical functions, and thus affects their growth and development. 相似文献
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