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1.
Total mercury distribution in different tissues of six species of freshwater fish from the Kpong hydroelectric reservoir in Ghana 总被引:1,自引:0,他引:1
Total mercury concentrations were determined in seven tissues of 38 fish samples comprising six species from the Kpong hydroelectric
reservoir in Ghana by cold vapour atomic absorption spectrometry technique using an automatic mercury analyzer. Mercury concentration
in all the tissues ranged from 0.005 to 0.022 μg/g wet weight. In general, the concentration of mercury in all the tissues
were decreasing in the order; liver > muscle > intestine > stomach > gonad > gill > swim bladder. Mercury concentration was
generally greater in the tissues of high-trophic-level fish such as Clarotes laticeps, Mormyrops anguilloides and Chrysichthys aurutus whereas low-trophic-level fish such as Oreochromis niloticus recorded low mercury concentration in their tissues. The results obtained for total mercury concentration in the muscle tissues
analysed in this study are below the WHO/FAO threshold limit of 0.5 μg/g. This suggests that the exposure of the general public
to Hg through fish consumption can be considered negligible. 相似文献
2.
This study presents concentration levels of pollutants (lead, and cadmium) in tissues (livers, kidneys, muscles, and bones)
of shorebirds (Kentish Plovers (n = 5), Mongolian Plovers (n = 2), Dunlins (n = 6), Great Knots (n = 10), Terek Sandpipers (n = 10)) from Yeongjong Island, Korea in the East Asian–Australian migration flyways during the autumn migration in 1994–1995.
Lead concentrations in livers, in kidneys, in muscles, and in bones were significantly different among shorebird species.
Lead concentrations in livers of Kentish Plovers (4.76 ± 2.72 μg/wet g), Mongolian Plovers (2.05 μg/wet g), Dunlins (3.77 ± 1.07 μg/wet
g), and Great Knots (4.27 ± 3.19 μg/wet g) were less than the toxic level, and lead concentrations in livers of Terek Sandpipers
(1.20 ± 0.94 μg/wet g) were at the background level. Cadmium concentrations in livers, in kidneys, in muscles, and in bones
did not vary among shorebirds, and concentrations of cadmium in livers and in kidneys were at background level (respectively,
approximate 1 μg/wet g, approximate 2.67 μg/wet g) in all shorebird species. We suggest that interspecific differences of
lead and cadmium concentrations were attributed to differences in exposure time and differences of diet, microhabitats in
wintering ground. In livers and kidney of shorebirds from Yeongjong Island, lead and cadmium concentrations were higher than
other locations previously reported. 相似文献
3.
This study investigated the presence of total mercury (Hg) and organic mercury levels in the muscle of 19 common fresh water
fish species captured from river Ganges, West Bengal, India. The total mercury level found in our study may not cause any
toxic effect, but the methyl mercury (MeHg) level in some freshwater fish species was surprisingly very high and toxically
unacceptable. The results of mercury analysis in various specimens indicated that some fish muscles tended to accumulate high
levels of Hg, and approximately 50–84% of Hg was organic mercury. A strong positive correlation between mercury levels in
muscle with food habit and fish length (age) was found. Wallago attu possessed the highest amount of organic mercury in their muscle tissues, and it was 0.93 ± 0.61 μg Hg/g of wet weight. Whereas
in small-sized fishes Eutropiichthys murius, Puntius sarana, Cirrhinus mrigala, Mystus vittatus or Mystus gulio, and Tilapia mossambicus, it was below the detection limit. Contamination in Catla catla (0.32 ± 0.11), Anguilla bengalensis bengalensis (0.26 ± 0.07 μg Hg/g), Chitala chitala (0.25 ± 0.18), Rita rita (0.34 ± 0.14), and Ompok pabda (0.26 ± 0.04) was also above the 0.25 μg Hg/g of wet weight, the limit set by the PFA for the maximum level for consumption
of fish exposed to MeHg. Though in Labeo rohita (0.12 ± 0.03), Mastacembelus armatus (0.17 ± 0.02), Pangasius pangasius (0.12 ± 0.16), Bagarius bagarius (0.12 ± 0.01), and Clupisoma garua (0.1 ± 0.01), concentration was below the recommended level, in Lates calcarifer (0.23 ± 0.0) and Mystus aor (0.23 ± 0.1), it was threatening. Interestingly, a low concentration of Hg was found in post-monsoon samples. 相似文献
4.
Wigand C McKinney RA Cole ML Thursby GB Cummings J 《Environmental monitoring and assessment》2007,131(1-3):71-81
The stable nitrogen isotope ratios of some biota have been used as indicators of sources of anthropogenic nitrogen. In this
study the relationships of the stable nitrogen isotope ratios of marsh plants, Iva frutescens (L.), Phragmites australis (Cav.) Trin ex Steud, Spartina patens (Ait.) Muhl, Spartina alterniflora Loisel, Ulva lactuca (L.), and Enteromorpha intestinalis (L.) with wastewater nitrogen and land development in New England are described. Five of the six plant species (all but U. lactuca) showed significant relationships of increasing δ
15N values with increasing wastewater nitrogen. There was a significant (P < 0.0001) downward shift in the δ
15N of S. patens (6.0 ± 0.48‰) which is mycorrhizal compared with S. alterniflora (8.5 ± 0.41‰). The downward shift in δ
15N may be caused by the assimilation of fixed nitrogen in the roots of S. patens. P. australis within sites had wide ranges of δ
15N values, evidently influenced by the type of shoreline development or buffer at the upland border. In residential areas,
the presence of a vegetated buffer (n = 24 locations) significantly (P < 0.001) reduced the δ
15N (mean = 7.4 ± 0.43‰) of the P. australis compared to stands where there was no buffer (mean = 10.9 ± 1.0‰; n = 15). Among the plant species, I. frutescens located near the upland border showed the most significant (R
2 = 0.64; P = 0.006) inverse relationship with the percent agricultural land in the watershed. The δ
15N of P. australis and I. frustescens is apparently an indicator of local inputs near the upland border, while the δ
15N of Spartina relates with the integrated, watershed-sea nitrogen inputs. 相似文献
5.
Total mercury concentrations in different tissues of frigate tuna fish (Auxis thazard thazard) was determined by the cold vapour atomic absorption spectrometry technique using an automatic mercury analyzer. A mixture
of HNO3, HClO4 and H2SO4 was used for complete oxidation of organic tissue. The concentration of mercury obtained was in the order Gills < Stomach
< Gonads < Intestine < Heart < Duodenum < Liver < Muscle. The concentration of total mercury detected in the edible muscle
tissue of the tuna fish tested ranged from 0.044 to 0.201 μg g−1 (mean = 0.108 μg g−1) wet weight. These levels are all within the maximum allowed/recommended level in fish (0.5 μg g−1 wet weight) set by the Food and Agriculture Organisation/World Health Organisation (FAO/WHO) and are therefore unlikely to
constitute any significant mercury exposure to the general population because of consumption of tuna fish. The results of
the study suggest a relatively clean marine environment that has not been significantly impacted by mercury contamination
probably due to minimal industrial activity in the region. 相似文献
6.
Despite California policies requiring assessment of ambient wetland condition and compensatory wetland mitigations, no intensive
monitoring tools have been developed to evaluate freshwater wetlands within the state. Therefore, we developed standardized,
wadeable field methods to sample macroinvertebrate communities and evaluated 40 wetlands across Northern California to develop
a macroinvertebrate index of biotic integrity (IBI). A priori reference sites were selected with minimal urban impacts, representing
a best-attainable condition. We screened 56 macroinvertebrate metrics for inclusion in the IBI based on responsiveness to
percent urbanization. Eight final metrics were selected for inclusion in the IBI: percent three dominant taxa; scraper richness;
percent Ephemeroptera, Odonata, and Trichoptera (EOT); EOT richness; percent Tanypodinae/Chironomidae; Oligochaeta richness;
percent Coleoptera; and predator richness. The IBI (potential range 0–100) demonstrated significant discriminatory power between
the reference (mean = 69) and impacted wetlands (mean = 28). It also declined with increasing percent urbanization (R
2 = 0.53, p < 0.005) among wetlands in an independent validation dataset (n = 14). The IBI was robust in showing no significant bias with environmental gradients. This IBI is a functional tool to determine
the ecological condition at urban (stormwater and flood control ponds), as well as rural freshwater wetlands (stockponds,
seasonal wetlands, and natural ponds). Biological differences between perennial and non-perennial wetlands suggest that developing
separate indicators for these wetland types may improve applicability, although the existing data set was not sufficient for
exploring this option. 相似文献
7.
Statistical source identification of metals in groundwater exposed to industrial contamination 总被引:1,自引:0,他引:1
Tariq SR Shah MH Shaheen N Jaffar M Khalique A 《Environmental monitoring and assessment》2008,138(1-3):159-165
Levels of selected metals Na, Ca, Mg, K, Fe, Mn, Cr, Co, Ni, Cd, Pb and Mn were estimated by flame atomic absorption spectrophotometry
in groundwater samples from Kasur, a significant industrial city of Pakistan. Salient mean concentration levels were recorded
for: Na (211 mg/l), Ca (187 mg/l), Mg (122 mg/l), K (87.7 mg/l), Fe (2.57 mg/l) and Cr (2.12 mg/l). Overall, the decreasing
metal concentration order was: Na > Ca > Mg > K > Fe > Cr > Zn > Co > Pb > Mn > Ni > Cd. Significantly positive correlations
were found between Na–Cr (r = 0.553), Na–Mn (r = 0.543), Mg–Fe (r = 0.519), Mg–Cr (r = 0.535), Pb–K (r = 0.506) and Pb–Ni (r = 0.611). Principal Component Analysis and Cluster Analysis identified tannery effluents as the main source of metal contamination
of the groundwater. The present metal data showed that Cr, Pb and Fe levels were several times higher than those recommended
for water quality by WHO, US-EPA, EU and Japan. The elevated levels of Cr, recorded as 21–42 fold higher compared with the
recommended quality values, were believed to originate from the tanning industry of Kasur. 相似文献
8.
Retrieval of total suspended matter (TSM) and chlorophyll-a (Chl-a) concentration from remote-sensing data for drinking water resources 总被引:1,自引:0,他引:1
Song K Li L Wang Z Liu D Zhang B Xu J Du J Li L Li S Wang Y 《Environmental monitoring and assessment》2012,184(3):1449-1470
The concentrations of chlorophyll-a (Chl-a) and total suspended matter (TSM) are major water quality parameters that can be retrieved using remotely sensed data. Water
sampling works were conducted on 15 July 2007 and 13 September 2008 concurrent with the Indian Remote-Sensing Satellite (IRS-P6)
overpass of the Shitoukoumen Reservoir. Both empirical regression and back-propagation artificial neural network (ANN) models
were established to estimate Chl-a and TSM concentration with both in situ and satellite-received radiances signals. It was found that empirical models performed
well on the TSM concentration estimation with better accuracy (R
2 = 0.94, 0.91) than their performance on Chl-a concentration (R
2 = 0.62, 0.75) with IRS-P6 imagery data, and the models accuracy marginally improved with in situ spectra data. Our results
indicated that the ANN model performed better for both Chl-a (R
2 = 0.91, 0.82) and TSM (R
2 = 0.98, 0.94) concentration estimation through in situ collected spectra; the same trend followed for IRS-P6 imagery data
(R
2 = 0.75 and 0.90 for Chl-a; R
2 = 0.97 and 0.95 for TSM). The relative root mean square errors (RMSEs) from the empirical model for TSM (Chl-a) were less than 15% (respectively 27.2%) with both in situ and IRS-P6 imagery data, while the RMSEs were less than 7.5% (respectively
18.4%) from the ANN model. Future work still needs to be undertaken to derive the dynamic characteristic of Shitoukoumen Reservoir
water quality with remotely sensed IRS-P6 or Landsat-TM data. The algorithms developed in this study will also need to be
tested and refined with more imagery data acquisitions combined with in situ spectra data. 相似文献
9.
The technique of diffusion gradient in thin films (DGT) for assessing bioavailable metals has not been tested under field
conditions. We assessed the relationships of DGT- and cation exchange resin-membrane-measured concentrations of Cd, Cu, Pb,
and Zn with plant uptake of the metals under greenhouse and field conditions. In the greenhouse, the effective concentrations
of Cu, Pb, and Zn by DGT correlated significantly with uptake by sorghum (Sorghum bicolor), but cation exchange resin-membrane-measured concentrations of Cd, Pb, and Zn did not correlate with sorghum uptake. In
the field, the DGT-measured concentrations of Cd, Pb, and Zn were not linearly related to uptake Cd, Pb, and Zn by lettuce
(Lactuca sativa) except for Cu uptake (r = 0.87, p < 0.05). Similarly, it was only the resin-membrane-extractable Pb that correlated with Pb uptake by lettuce (r = 0.77; p < 0.05). However, fitting non-linear regression models improved the plant metal uptake predictions by DGT-measured bioavailable
Cd, Cu, Pb, and Zn under field conditions. In conclusion, the DGT technique was fairly predictive of bioavailability in the
greenhouse, but not in the field. 相似文献
10.
Disturbance by military maneuvers over short and long time scales may have differential effects on grassland communities.
We assessed small mammals as indicators of disturbance by military maneuvers in a mixed prairie in southern Oklahoma USA.
We examined sites on two soil series, Foard and Lawton, across a gradient of disturbance intensity. A MANOVA showed that abundance
of small mammals was associated (p = 0.03) with short-term (cover of vehicle tracks) disturbance but was not associated (p = 0.12) with long-term (loss of soil organic carbon, SOC) disturbance intensity. At the individual species level, Sigmodon hispidus (cotton rat) and Peromyscus maniculatus (deer mouse) occurred across all levels of disturbance and in both soil types. Only P. maniculatus abundance changed (p < 0.01) with short-term disturbance and increased by about one individual per 5% of additional track-cover. Abundance of
P. maniculatus also increased (p = 0.04) by about three individuals per 1% increase in soil carbon. Chaetodipus hispidus (hispid pocket mouse) and Reithrodontomys fulvescens (fulvous harvest mouse) only occurred in single soil types limiting their potential as more general indicators. Abundance
of P. maniculatus was positively related to shifts in plant species composition and likely reflected changes in vegetation structure (i.e.
litter depth) and forage availability resulting from disturbance. Peromyscus maniculatus may be a useful biological indicator of ecosystem change because it responded predictably to both long-term and short-term
disturbance and, when coupled with soil, plant, and disturbance history variables, can reveal land condition trends. 相似文献
11.
We compared levels of eight heavy metals in common tern eggs collected in 1982 (n=24) from coastal New Jersey with archived specimens collected from the same colonies in 1971 (N=9). Levels of all metals, except cobalt, showed a significant decrease over the 11 year period, with lead and nickel showing the greatest decline. Mercury levels declined over 50% based on geometric means. Cadmium and mercury showed the lowest levels in both years. Pair-wise correlation coefficients on log-transformed data revealed lower correlations in 1971, whereas most metal pairs showed significant correlations in 1982. Mercury levels showed significant positive correlations with cobalt, cadmium, and nickel in 1971, but were not correlated with levels of any other metal in 1982. 相似文献
12.
Reddy KJ Kumar JR Ramachandraiah C Reddy SA Reddy AV 《Environmental monitoring and assessment》2008,136(1-3):337-346
N-Ethyl-3-cabazolecarboxaldehydethiosemicarbazone (ECCT) is proposed as a new, sensitive and selective complexing reagent
for the separation and extractive spectrophotometric determination of palladium(II) at pH: 4.0 to form a yellowish orange
colored 1:1 chelate complex, which is very well extracted in to n-butanol. The absorbance was measured at a maximum wavelength,
410 nm. This method obeys Beer’s law in the concentration range 0.0–6.6 μg mL−1 and the correlation coefficient of Pd(II)-ECCT complex is 0.998, which indicates an excellent linearity between the two variables
with good molar absorptivity and Sandell’s sensitivity, 1.647 × 104 l mol−1cm−1, 6.49 × 10−3 μg cm−2, respectively. The instability constant of complex calculated from Edmond’s method, 2.724 × 10−5 was in good agreement with the value calculated from Asmus’ method 2.624 × 10−5, at room temperature. The precision and accuracy of the method is checked with calculation of relative standard deviation
(n = 5), 0.839. Edmond’s method was observed to be a more selective method in the presence of EDTA, oxalate and phosphate ions.
The method was successfully applied for the determination of Pd(II) in water samples, synthetic mixtures and hydrogenation
catalysts, employing an atomic absorption spectrometer for comparing these results. 相似文献
13.
Mercury concentration in the muscle of seven fish species from Chagan Lake,Northeast China 总被引:2,自引:0,他引:2
Chagan Lake is located downstream of the Second Songhua River basin in Northeast China. It is one of the top ten inland freshwater
lakes, and an important aquatic farm in China. The lake has been receiving large amounts (currently at 1.5 × 108 m3/a) of water from the river since 1984. This would pose a threat to the aquatic system of the lake because the river was seriously
polluted with mercury in 1970s–1980s. The current study is the first to report the total mercury concentrations in fish found
in the lake. Mercury concentrations in seven fish species collected from the lake in January 2009 were determined. The related
human health risk from fish consumption was also assessed. The average concentration of mercury in the fish was 18.8 μg/kg
of wet weight, ranging from 4.5 to 37.6 μg/kg of wet weight. A large difference in the mercury concentrations among the fish
species was found. The mercury concentration was found to be higher in carnivorous species and lower in omnivorous and herbivorous
species. This demonstrates greater mercury bioaccumulation in fish species at higher trophic levels. Mercury concentrations
in fish showed significant positive correlations with age, length, and weight. No significant relationship was found between
mercury concentrations in fish and the habitat preferences. Mercury concentrations in fish from the lake were within the limits
of the international and national standards of China established for mercury. According to the reference doses established
by the United States Environmental Protection Agency, the maximum safe consuming quantity considering all the fish was 297.3 g/day/person,
which was more than five times as much as the current quantity (50 g/day/person) consumed by the local residents. This investigation
indicates that the historical pollution of the Second Songhua River has not caused mercury bioaccumulation in fish muscle
tissue of Chagan Lake. The present consumption of fish from the lake in the local area does not pose a threat to human health. 相似文献
14.
Delta-aminolevulinate dehydratase (ALAD) activity has been used in prokaryotes and eukaryotes as a biomarker for environmental
lead (Pb) exposure and toxicity. Microorganisms are sensitive indicators of toxicity at the fundamental level of ecological
organization, but bacterial biomarker studies are focused on the Pseudomonas strains in Group I and E coli. The objectives of the present work were to determine if Burkholderia gladioli belonging to group II, due to its 16SrRNA similarity, can be used as biomarker in metal contamination and compare its possible
usage with Pseudomonas aeruginosa and Citrobacter freundii (previously known as Esherichia freundii) and Bacterium freundii which are classified in Group I. In this study, ALAD activity in an environmental strains of Burkholderia gladioli, Pseudomonas aeruginosa, Citrobacter freundii were investigated to evaluate potential inhibition by Pb and other toxic metals. When the ALAD activity of Burkholderia gladioli was tested, Co and Pb decreased activity by 27 and 71%, respectively. In addition to these findings, Zn increased the activity
up to 26%. These effects were found to be statistically meaningful (p < 0.05). It was determined that the increase of lead concentration inhibites the ALAD activity at each of the three strains.
There was a statistically significant dose–response relationship between ALAD activity in cells of Burkholderia gladioli and Pb (Pearson correlation coefficent = −0.665; r
2 = 0.665, and p < 0.001). The strongest ALAD inhibition which was measured was 90% at Burkholderia gladioli when protein extracts were incubated with 750 μM of Pb. The relationship between Pb and ALAD activity was statistically described
by [ALAD Activity] = 0.476−0.000597 × [Pb]. According to the obtained results, we suggest that the ALAD of Burkholderia gladioli can be used as a biomarker for lead contamination in the environment. 相似文献
15.
Fecal source tracking by antibiotic resistance analysis on a watershed exhibiting low resistance 总被引:2,自引:0,他引:2
The ongoing development of microbial source tracking has made it possible to identify contamination sources with varying accuracy,
depending on the method used. The purpose of this study was to test the efficiency of the antibiotic resistance analysis (ARA)
method under low resistance by tracking the fecal sources at Turkey Creek, Oklahoma exhibiting this condition. The resistance
patterns of 772 water-isolates, tested with nine antibiotics, were analyzed by discriminant analysis (DA) utilizing a five-source
library containing 2250 isolates. The library passed various representativeness tests; however, two of the pulled-sample tests
suggested insufficient sampling. The resubstitution test of the library individual sources showed significant isolate misclassification
with an average rate of correct classification (ARCC) of 58%. These misclassifications were explained by low antibiotic resistance
(Wilcoxon test P < 0.0001). Seasonal DA of stream E. coli isolates for the pooled sources human/livestock/deer indicated that in fall, the human source dominated (P < 0.0001) at a rate of 56%, and that human and livestock respective contributions in winter (35 and 39%), spring (43 and
40%), and summer (37 and 35%) were similar. Deer scored lower (17–28%) than human and livestock at every season. The DA was
revised using results from a misclassification analysis to provide a perspective of the effect caused by low antibiotic resistance
and a more realistic determination of the fecal source rates at Turkey Creek. The revision increased livestock rates by 13–14%
(0.04 ≤ P ≤ 0.06), and decreased human and deer by 6–7%. Negative misclassification into livestock was significant (0.04 ≤ P ≤ 0.06). Low antibiotic resistance showed the greatest effect in this category. 相似文献
16.
Woli KP Hayakawa A Kuramochi K Hatano R 《Environmental monitoring and assessment》2008,137(1-3):251-260
River water quality was evaluated with respect to eutrophication and land use during spring snowmelt and summer base flow
periods in Abashiri (mixed cropland-livestock farming) and Okoppe (grassland-based dairy cattle farming), eastern Hokkaido,
Japan. Water from rivers and tributaries was sampled during snowmelt and summer base flow periods in 2005, and river flow
was measured. Total N (TN), NO3–N, and Si concentrations were determined using standard methods. Total catchment and upland areas for each sampling site
were determined with ArcGIS hydrology modeling software and 1:25,000-scale digital topographic maps. Specific discharge was
significantly higher during snowmelt than during base flow. In both areas, TN concentrations increased, whereas Si concentrations
decreased, with increased specific discharge, and were significantly higher during snowmelt. The Si:TN mole ratio decreased
to below or close to the threshold value for eutrophication (2.7) in one-third of sites during snowmelt. River NO3–N concentrations during base flow were significantly and positively correlated with the proportion of upland fields in the
catchment in both the Abashiri (r = 0.88, P < 0.001) and Okoppe (r = 0.43, P < 0.01) areas. However, the regression slope, defined as the impact factor (IF) of water quality, was much higher in Abashiri
(0.025) than in Okoppe (0.0094). The correlations were also significantly positive during snowmelt in both areas, but IF was
four to eight times higher during snowmelt than during base flow. Higher discharge of N from upland fields and grasslands
during snowmelt and the resulting eutrophication in estuaries suggest that nutrient discharge during snowmelt should be taken
into account when assessing and monitoring the annual loss of nutrients from agricultural fields. 相似文献
17.
The degree at which tropical forests are exposed to human pressure is spatially dependent. Population density, proximity to
roads, terrain slope, logging activities and land distribution projects are well known factors inducing deforestation and
forest degradation in Latin America. Using expert knowledge to weight these threat factors and a Geographical Information
System for spatial modeling, a multi-criteria analysis procedure is presented, that allows stratifying a study region in categories
of deforestation threat. The procedure was implemented in the Central Volcanic Mountain Range Conservation Area (CVMRCA) in
Costa Rica with the purpose of finding areas with a combination of physical and socioeconomic characteristics that is particularly
predisposing to a high probability of deforestation. To validate the map, the CVMRCA was stratified in categories of deforestation
risk, and the result was superposed to historical deforestation data of the period 1986–1996. The good correlation between
risk category and historical deforestation (r = 0.91, p < 0.001) indicates that the map can be used as a decision support tool for defining priority areas for conservation action. 相似文献
18.
A method for the preconcentration of the total chromium based on coprecipitation with cerium (IV) hydroxide is proposed for
determination of chromium by flame atomic absorption spectrometry. Different factors including carrier element amount, pH,
sample volume and matrix ion effects for the precipitation were examined. The detection limit of the total chromium (k = 3, N = 15) was 0.18 μg l−1. The presented method was applied for the determination of chromium in the wastewater samples from Kayseri and Nigde Organized
Industrial Region-Turkey and in drinking water from our laboratory, Kayseri with satisfactory results (relative standard deviations
below 8%, recoveries 95%). The analytical results obtained by the proposed method for certified copper sample was in good
agreement with the certified value. 相似文献
19.
A. Alomary I. F. Al-Momani S. M. Obeidat A. M. Massadeh 《Environmental monitoring and assessment》2013,185(4):3283-3295
The aim of this study was to measure the concentrations of lead (Pb), cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in deciduous teeth from children living in Jordan and to investigate the affecting factors. Deciduous teeth samples (n?=?320, without fillings) were collected from 5- to 12-year-old children and analyzed for Pb, Cd, Cu, Fe, and Zn using inductively coupled plasma–optical emission spectrometry. A questionnaire was used to gather information on each child, such as sex, age, tooth type (incisors, canines, and molars), tooth position within the mouth (upper or lower jaw), caries status, presence of amalgam fillings inside the mouth, type of drinking water (tap water, home purified water, and plant purified water), and zone of residence (close to or far from heavy traffic roads). The mean concentrations of Pb, Cd, Cu, Fe, and Zn were 30.26, 0.55, 6.23, 34.72, and 128.21 μg/g, respectively. Our results indicate that there is a clear relation between the concentrations of the metals analyzed in this study and tooth type, tooth position within the mouth, caries status, presence of amalgam fillings inside the mouth, and type of drinking water. No significant differences in the concentrations of the five metals analyzed were observed due to sex. Our results also show that no significant difference among Pb, Cd, Cu, Fe, and Zn concentrations and age among the ages of 5–6, 7–8, 9–10, and 11–12, except for Pb, which decreases at age 11–12. 相似文献
20.
Vikas Eknath Mahajan Raju Ravindra Yadav Narayan Purushottam Dakshinkar Vinod Madanlal Dhoot Gautam Ramkrishna Bhojane Madhura Kiran Naik Preeti Shrivastava Pravin Krishnarao Naoghare Kannan Krishnamurthi 《Environmental monitoring and assessment》2012,184(12):7365-7372
Cattle grazing nearby coal-fired power stations are exposed to fly ash. The present investigation aims to assess the environmental and health impacts of fly ash containing mercury emitted from thermal power plant. The health effect of fly ash were studied using 20 lactating cattle reared within a 5-km radius of s thermal power plant for the possible effect of fly ash such as the alterations in hematological and biochemical parameters of blood, milk, and urine. Results indicated that the hemoglobin levels (6.65?±?0.40?g/dl) were significantly reduced in all the exposed animals. Biochemical parameters viz., blood urea nitrogen (27.35?±?1.19?mg/dl), serum glutamate oxaloacetate transaminase (43.39?±?3.08?IU/l), albumin, and creatinine were found to be increased, whereas serum glutamate pyruvic transaminase (29.26?±?2.02) and Ca2+ were observed to be statistically insignificant in exposed animals. Mercury concentrations estimated in the blood, milk, and urine of exposed (n?=?20) and control (n?=?20) animals were 7.41?±?0.86, 4.75?±?0.57, 2.08?±?0.18, and 1.05?±?0.07, 0.54?±?0.03, 0.20?±?0.02?μg/kg, respectively. The significant increase (P?<?0.01) in the levels of mercury in blood, milk, and urine of exposed animals in comparison to control indicated that the alterations of biochemical parameters in exposed cattle could be due to their long term exposure to fly ash mercury which may have direct or indirect impact on human populations via food chain. 相似文献