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1.
Al-Tayar NG Nagaraja P Vasantha RA Shresta AK 《Environmental monitoring and assessment》2012,184(1):181-191
A simple, rapid, and sensitive method involving the interaction of 2,4-dinitrophenylhydrazine with imipramine hydrochloride
in presence of vanadium (V) in sulfuric acid medium has been proposed for the determination of vanadium. The purple-colored
product developed showed an absorption maximum at 560 nm and was stable for 24 h. The working curve was linear over the concentration
range of 0.1–2.8 μg ml − 1, with sensitivity of detection of 0.0124 μg ml − 1. Molar absorptivity and Sandell’s sensitivity were found to be 2.6 × 104 l/mol cm and 0.0039 μg cm − 1, respectively. The accuracy of the proposed method was assessed by Student’s t test and variance ratio F test, and the results were on par with the reported method. The method was successfully used in the determination of V in
water, human urine, soil, and plant samples, and it was free from interference by various concomitant ions. 相似文献
2.
Nagpur City located in semiarid area of central India is a fast-growing industrial centre. In recent years, rapid development
has created an increased demand for drinking water, which is increasingly being fulfilled by groundwater abstraction. The
present study was undertaken to assess major ion chemistry of shallow groundwater to understand geochemical evolution of groundwater
and water quality for promoting sustainable development and effective management of groundwater resources. A total of 47 water
samples were collected from shallow aquifer of selected parts of the city and the water chemistry of various ions viz. Ca2 + , Mg2 + , Na + , K + , CO3 2-_{3}^{\ \, 2-}, HCO3 -_{3}^{\ \, -}, Cl − , SO4 2-_{4}^{\ \,2-} and NO3 -_{3}^{\ \,-} are carried out. The chemical relationships in Piper diagram identify Ca–HCO3–Cl and mixed Ca–Na–HCO3–Cl as most prevalent water types. Alkaline earth exceeds alkalis and weak acids exceed strong acids. Ionic ratios and Gibb’s
diagram suggest that silicate rock weathering and anthropogenic activities are the main processes that determine the ionic
composition in the study area. The nitrate appeared as a major problem of safe drinking water in this region. We recorded
highest nitrate concentration, i.e., 411 mg/l in one of the dug well. A comparison of groundwater quality in relation to drinking
water quality standards revealed that about half of the shallow aquifer samples are not suitable for drinking. 相似文献
3.
A sensitive spectrophotometric method has been developed for determination of ametryn in agricultural samples. The proposed
method was based on reaction with pyridine and further coupling with sulfanilic acid to form a colored product. The absorbance
was measured at 400 nm with a molar absorptivity of 2.1 × 105 L mol−1 cm−1. The method shows a linear range from 0.2–20 μg mL−1 with limit of detection and limit of quantification 0.16 and 0.54 μg mL−1, respectively. The method has been successfully applied to the determination of ametryn in sugarcane juice and commercial
formulations after separation of ametryn from triazine herbicides based on solvent extraction. Recovery values were found
to be in the range of 96.0 ± 0.2% to 98.4 ± 0.1%. 相似文献
4.
Michailova P Warchałowska-Śliwa E Szarek-Gwiazda E Kownacki A 《Environmental monitoring and assessment》2012,184(1):1-14
The investigation was carried out on a small pond situated on a recent mine spoil at Bolesław in the Olkusz region with Zn–Pb
ore deposits. Water of the pond had pH 7.2–8.5 and low concentrations of heavy metals. Concentrations of Pb (487 μg g − 1) and Zn (1,991 μg g − 1) in the sediment were very high and potentially could lead to toxicological effects. In the pond, 48 taxa of macroinvertebrates
belonging to Oligochaeta and water stages of Ephemeroptera, Odonata, Megaloptera, Trichoptera, Heteroptera, Coleoptera and
Diptera (mainly Chironomidae family) were found. The influence of heavy metals on macroinvertebrates diversity was not found.
Effect of heavy metal pollution was observed on the appearance of chromosome aberrations in the polytene chromosomes of Chironomidae
larvae. It was manifested by two ways: (1) in Kiefferulus tendipediformis and Chironomus sp. chromosome rearrangements in fixed state (tandem fusion and homozygous inversions), indicated intensive process of speciation;
(2) in Chironomus sp., K. tendipediformis, Glyptotendipes gripekoveni (Chironomidae) somatic chromosome rearrangements (inversions, deficiencies, specific puffs, polyploidy) affected few cells
of every individual. The somatic functional and structural alterations in Chironomidae species are particular suitable as
biomarkers—they can be easily identified and used for detecting toxic agents in the environment. 相似文献
5.
Díaz A Arnedo R Céspedes-Sánchez R Devesa R Martin-Alonso J 《Environmental monitoring and assessment》2012,184(1):539-548
A performance study of diffusive gradients in thin films (DGT) and inductively coupled plasma optical emission spectrometry
(ICP-OES) was applied for the monitoring of the labile fraction of metals Al, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn, in Sant
Joan Despí Drinking Water Treatment Plant located in the South of Barcelona’s Metropolitan Area (Spain). The DWTP monitoring
protocol was optimized by working for 1 day of deployment (24 h) with the DGT device in contact with both treated and river
water matrixes. Additionally, it was demonstrated that an increase in the deployment time of 1 week did not decrease the evaluated
concentrations of the studied metals. The quality parameters of the DGT device and ICP-OES determination, such as limit of
quantification, accuracy expressed as relative error (%) and reproducibility expressed as relative standard deviation, were
evaluated. Good results were obtained for all the metals in ultrapure water; limits of quantification ranged from 1.5 μg L − 1 for cadmium to 28 μg L − 1 for zinc when deployment time of 24 h was used and from 0.2 μg L − 1 for cadmium to 4 μg L − 1 for zinc when this time was increased by 1 week. Accuracy and precisions lower than or equal to 10% were obtained at a parametric
concentration value of the metals regulated in the European Drinking Water Guidelines (98/83/EC). DGT deployment was tested
in river and treated water, and good results were obtained for Cd, Ni, Co and Zn, whereas for the other metals, a continuous
control of their metallic labile fractions was monitored. Therefore, DGT device allows the continuous monitoring of the labile
metal species in a drinking water treatment plant. 相似文献
6.
Chrastný V Vaněk A Teper L Cabala J Procházka J Pechar L Drahota P Penížek V Komárek M Novák M 《Environmental monitoring and assessment》2012,184(4):2517-2536
The soils adjacent to an area of historical mining, ore processing and smelting activities reflects the historical background
and a mixing of recent contamination sources. The main anthropogenic sources of metals can be connected with historical and
recent mine wastes, direct atmospheric deposition from mining and smelting processes and dust particles originating from open
tailings ponds. Contaminated agriculture and forest soil samples with mining and smelting related pollutants were collected
at different distances from the source of emission in the Pb–Zn–Ag mining area near Olkusz, Upper Silesia to (a) compare the
chemical speciation of metals in agriculture and forest soils situated at the same distance from the point source of pollution
(paired sampling design), (b) to evaluate the relationship between the distance from the polluter and the retention of the
metals in the soil, (c) to describe mineralogy transformation of anthropogenic soil particles in the soils, and (d) to assess
the effect of deposited fly ash vs. dumped mining/smelting waste on the mobility and bioavailability of metals in the soil.
Forest soils are much more affected with smelting processes than agriculture soils. However, agriculture soils suffer from
the downward metal migration more than the forest soils. The maximum concentrations of Pb, Zn, and Cd were detected in a forest
soil profile near the smelter and reached about 25 g kg − 1, 20 g kg − 1 and 200 mg kg − 1 for Pb, Zn and Cd, respectively. The metal pollutants from smelting processes are less stable under slightly alkaline soil
pH then acidic due to the metal carbonates precipitation. Metal mobility ranges in the studied forest soils are as follows:
Pb > Zn ≈ Cd for relatively circum-neutral soil pH (near the smelter), Cd > Zn > Pb for acidic soils (further from the smelter).
Under relatively comparable pH conditions, the main soil properties influencing metal migration are total organic carbon and
cation exchange capacity. The mobilization of Pb, Zn and Cd in soils depends on the persistence of the metal-containing particles
in the atmosphere; the longer the time, the more abundant the stable forms. The dumped mining/smelting waste is less risk
of easily mobilizable metal forms, however, downward metal migration especially due to the periodical leaching of the waste
was observed. 相似文献
7.
Total selenium (Se) and water-soluble Se in soil, and Se in a shallow groundwater were hydrogeochemically researched in an
alluvial fan area in Tsukui, Central Japan. The water-soluble Se was estimated at average level of 2.6 ± 1.2μg Se kg−1 dry soil (± SD, n = 25), showing less than 1% of the total Se (349–508μg Se kg−1 dry soil) in soil. The monthly Se concentration in groundwater was average 2.2μg,L−1, ranging 1.6–2.4μg,L−1 during 2001–2003. The Se in groundwater significantly decreased with increasing groundwater level after rainfall. This result
indicated that Se-bearing water percolated with relatively low Se concentration through the soil layer. According to our prediction
model of linear regression curve on the observation data, Se concentration in the groundwater was estimated to be increasing
with the very low rate of 4.35 × 10−3μg Se L−1,yr−1. The hydrogeochemical research and the result of the prediction model showed that any explosive increase of Se will hardly
occur in this groundwater without an anthropogenic Se contamination. 相似文献
8.
Health risk assessment of heavy metals for edible parts of vegetables grown in sewage-irrigated soils in suburbs of Baoding City,China 总被引:1,自引:0,他引:1
Zhan-Jun Xue Shu-Qing Liu Yan-Ling Liu Yong-Lu Yan 《Environmental monitoring and assessment》2012,184(6):3503-3513
With the long-term application of wastewater to vegetable production fields, there is concern about potential health risks
of heavy metals contaminating the edible parts of vegetables grown in contaminated soils in the suburban areas of Baoding
City, China. The average concentration of elemental Zn in sewage-irrigated soil was the highest (153.77 mg kg−1), followed by Pb (38.35 mg kg−1), Cu (35.06 mg kg−1), Ni (29.81 mg kg−1), and Cd (0.22 mg kg−1) which were significantly higher (P < 0.05) than those in the reference soil. The results showed that long-term sewage irrigation had led to a growing accumulation
of heavy metals in the soils, especially for Cd, Zn, and Pb. Furthermore, the concentrations of elemental Cd, Zn, and Ni in
vegetables (e.g., Beassica pekinensis L., Allium fistulosum L., Spinacia oleracea L.) collected from the wastewater-irrigated soils exceeded the maximum permissible limits, and this also increased the daily
intake of metals by food. However, compared with the health risk index of <1 for heavy metals, the ingestion of vegetables
from the soils irrigated with sewage effluent posed a low health risk. Nevertheless, heavy metal concentrations should be
periodically monitored in vegetables grown in these soils together with the implementation effective remediation technologies
to minimize possible impacts on human health. 相似文献
9.
Padmalal D Remya SI Jyothi SJ Baijulal B Babu KN Baiju RS 《Environmental monitoring and assessment》2012,184(3):1541-1557
The southwestern coast of India is drained by many small rivers with lengths less than 250 km and catchment areas less than
6,500 km2. These rivers are perennial and are also the major drinking water sources in the region. But, the fast pace of urbanization,
industrialization, fertilizer intensive agricultural activities and rise in pilgrim tourism in the past four to five decades
have imposed marked changes in water quality and solute fluxes of many of these rivers. The problems have aggravated further
due to leaching of ionic constituents from the organic-rich (peaty) impervious sub-surface layers that are exposed due to
channel incision resulting from indiscriminate instream mining for construction-grade sand and gravel. In this context, an
attempt has been made here to evaluate the water quality and the net nutrient flux of one of the important rivers in the southwestern
coast of India, the Manimala river which has a length of about 90 km and catchment area of 847 km2. The river exhibits seasonal variation in most of the water quality parameters (pH, electrical conductivity, dissolved oxygen,
total dissolved solids, Ca, Mg, Na, K, Fe, HCO3, NO2-N, NO3-N, P
\text-inorg_{\rm \text{-}inorg}, P
\text-tot_{\rm \text{-}tot}, chloride, SO4, and SiO2). Except for NO3-N and SiO2, all the other parameters are generally enriched in non-monsoon (December–May) samples than that of monsoon (June–November).
The flux estimation reveals that the Manimala river transports an amount of 2,308 t y − 1 of dissolved inorganic nitrogen, 87 t y − 1 dissolved inorganic phosphorus, and 9246 t y − 1 of SO4, and 1984 t y − 1 K into the receiving coastal waters. These together constitute about 23% of the total dissolved fluxes transported by the
Manimala river. Based on the study, a set of mitigation measures are also suggested to improve the overall water quality of
small catchment rivers of the densely populated tropics in general and the south western coast in particular. 相似文献
10.
Presence of pesticide residues was studied in rain water during 2002 employing multi residue analysis method by gas liquid
chromatography equipped with ECD and NPD detectors and capillary columns. The presence of pesticide residues in surface aquatic
system triggered the investigation of the presence of pesticides in rain water. A total of 13 pesticides were detected in
rain water samples. Among the different groups of pesticides, organochlorines were present in the range of 0.041–7.060 ppb
with maximum concentration of p,p’-DDT up to 7.060 μg l−1. Synthetic pyrethroids were present ranging from 0.100 to 1.000 μg l−1 and organophosphates in the range of 0.050–4.000 μg l−1 showing maximum contamination with cypermethrin (1.000 μg l−1) and monocrotophos (4.000 μg l−1) of the respective groups. Almost 80% samples showed the residues above MRL of 0.5 ppb fixed for multi residues and on the
basis of single pesticide, 16–50% samples contained residues above the MRL value of 0.1 ppb. 相似文献
11.
Water quality assessment: surface water sources used for drinking and irrigation in Zaria,Nigeria are a public health hazard 总被引:1,自引:0,他引:1
Chigor VN Umoh VJ Okuofu CA Ameh JB Igbinosa EO Okoh AI 《Environmental monitoring and assessment》2012,184(5):3389-3400
We assessed the quality and pollution status of source surface waters in Zaria, Nigeria by monitoring the nature, cause and
extent of pollution in Samaru stream, Kubanni River and Kubanni dam over a period of 10 months, between March and December
2002. A total of 228 water samples was collected from 12 sites and analysed for a total of ten physicochemical and one bacteriological
quality indicators, using standard methods. Aesthetic water quality impairment parameters were also observed. The mean values
of most water quality parameters were significantly higher (P < 0.05) in both the stream and river than in the dam. There was no significant correlation between faecal coliform counts
(FCC) and water temperature (in the range 15–33°C); pH (5.77–7.32); and turbidity (1.4–567 NTU). The high FCC ranged from
2.0 × 101 to 1.6 × 106 MPN/100 ml and exceeded the WHO standards for drinking water and water used for fresh-produce irrigation, and correlated
positively (P < 0.05) with conductivity (in the range 68–1,029 μS/cm); TDS (10.0–70.0 mg/l); TSS (10.0–70.0 mg/l); Cl (7.5–181 mg/l); PO4−P (0.01–0.41 mg/l); NO3−N (0.6–3.8 mg/l) and BOD5 (0.1–14.9 mg/l). The main pollution sources were municipal wastewater, stormwater runoffs, the ABU sewage treatment plant,
abattoir effluents and irrigation farms treated with chemical fertilisers. We conclude that these water bodies are potentially
hazardous to public health and that proper sewage treatment and river quality monitoring are needed to warn against hazards
to public health. 相似文献
12.
Modeling Phosphate Influence on Arsenate Reduction Kinetics by a Freshwater Cyanobacterium 总被引:1,自引:0,他引:1
Arsenic speciation in natural surface-water systems can be highly impacted through biological processes that result in non-thermodynamically
predicted species to dominate the system. In laboratory experiments, arsenate reduction by a freshwater cyanobacterium exhibited
saturation kinetics increasingly inhibited by elevating solution phosphate concentrations. Approximately 100% arsenate reduction
occurred by days 4, 7, and 10 in the low (0.35 μm), middle (3.5 μm), and high (35 μm) phosphate treatments, respectively,
with maximum arsenate reduction rates ranged from 0.013 μmol As g C−1 day−1 in the high-phosphate treatment to 0.398 μmol As g C−1 day−1 in the low-phosphate treatment. Saturation kinetic models were utilized to evaluate the impact of cell growth and arsenate-phosphate
uptake competition on arsenate reduction rates by the cyanobacterium. Results showed reduced arsenicals dominate arsenic speciation
once growth reached steady state, indicating reduced arsenicals may dominate natural systems, even when considering conservatively
high, abiotic arsenic reoxidation. 相似文献
13.
Estimation of Polish cigarettes contamination with cadmium and lead, and exposure to these metals via smoking 总被引:2,自引:0,他引:2
Galazyn-Sidorczuk M Brzóska MM Moniuszko-Jakoniuk J 《Environmental monitoring and assessment》2008,137(1-3):481-493
To estimate exposure to cadmium (Cd) and lead (Pb) through cigarette smoking, the concentrations of both metals in the blood
or/and urine of smokers (20 cigarettes or more per day for 10 years or longer) and their non-smoking counterparts inhabiting
an environmentally unpolluted area (Bialystok, Poland) were evaluated, as well as Cd and Pb contents in the cigarette brands
(produced in Poland) smoked by the participants, including intact cigarettes, pre-smoking (tobacco, paper and filter) and
post-smoking (butt, ash and smoke) cigarette components. Blood and urinary Cd concentrations in the smokers have been already
reported by us to be 2–4 times higher than in the non-smokers (Galażyn-Sidorczuk et al. Polish Journal of Environmental Studies,
13 (Suppl.1):91–95, 2004). All the other measurements are the subject of the present paper. Pb concentration in the blood of the cigarette smokers
(52.12 ± 15.51 μg l−1) was higher by 29% than in the non-smokers (40.42 ± 11.19 μg l−1). The mean Cd and Pb contents in the cigarettes were 0.6801 ± 0.1765 and 0.6853 ± 0.0746 μg per cigarette, respectively.
Under cigarette burning, performed using a machine for self-acting burning, on average 33% of Cd and 11% of Pb present in
the whole cigarette was released into the smoke. For Cd, unlike Pb, there was a high positive correlation between the metal
content in cigarettes and tobacco and its release into the smoke. Moreover, the subjects smoking cigarettes containing the
highest Cd amount had higher blood Cd concentration than smokers of other cigarette brands. The results give clear evidence
that in the case of inhabitants of areas unpolluted with Cd and Pb habitual cigarette smoking, due to tobacco contamination,
creates a serious source of chronic exposure to these metals, especially to Cd. 相似文献
14.
von Bobrutzki K Ammon C Berg W Einert P Fiedler M Müller HJ Scherer D Strohbach B 《Environmental monitoring and assessment》2012,184(6):3775-3787
Agricultural NH3 emissions affect air quality and influence the nitrogen cycle. In the subject study, NH3 emissions from a broiler farm and the resulting atmospheric concentrations in the immediate vicinity during three growing
cycles have been quantified. Additionally, vegetation along a transect in an adjacent woodland was analysed. The emissions
were as high as 10 kg NH3 h−1 and the atmospheric concentrations ranged between 33 and 124 μg NH3 m−3 per week in the immediate vicinity. Measurements of the atmospheric concentrations over 7 weeks showed a substantial decline
of mean concentrations (based on a 3-week average) from ∼13 to <3 μg NH3 m−3, at 45- and 415-m distance from the farm. Vegetation surveys showed that nitrophilous species flourished when they grew closest
to the farm (their occurrence sank proportionately with distance). A clearly visible damage of pine trees was observed within
200 m of the farm; this illustrated the significant impact of NH3 emissions from agricultural sources on the sensitive ecosystem. 相似文献
15.
Accumulation and tolerance characteristics of cadmium in Chlorophytum comosum: a popular ornamental plant and potential Cd hyperaccumulator 总被引:3,自引:0,他引:3
The effects on the growth, physiological indexes and the cadmium (Cd) accumulation in Chlorophytum comosum under Cd stress were examined by pot-planting. The results showed that the tolerance index (TI) of C. comosum were all above 100 in soil Cd concentration of 100 mg kg − 1. The O2·-_{2^{\bullet}}^{-} production rate and electrical conductivity of C. comosum were significantly positively correlated to Cd adding-concentration while the MDA content increased and had significant differences
with the control. The activities of SOD, CAT, and POD all rose significantly in lower Cd concentration and the Cd threshold
of them were around 10, 50 and 20 mg kg − 1, respectively. The Cd in C. comosum root and aboveground part reached 1,522 and 865·5 mg kg − 1, respectively, in Cd concentration of soil up to 200 mg kg − 1. For the advantages of high tolerance, high accumulation, and high ornamental value, C. comosum may have tremendous application value in the treatment of Cd-contaminated soils. 相似文献
16.
Jun Yao WenBing Li FangFang Xia YuanGe Zheng ChengRan Fang DongSheng Shen 《Environmental monitoring and assessment》2012,184(6):3711-3720
Fly ash samples were taken from solid waste incinerators with different feeding waste, furnace type, and air pollution control
device in six cities of Zhejiang province. The solid waste incinerators there constitute one fifth of incinerators in China.
Heavy metals and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in the fly ash. Moreover, the fly ash samples were extracted by toxicity
characteristic leaching procedure (TCLP). The biotoxicity of the leachate was evaluated by Chlorella pyrenoidosa. High variation and contents were found for both the heavy metals and PCDD/Fs. The contents of Zn, Cu, As, Pb, Cd, Cr, Ni,
and Hg in the fly ash samples varied from 300 to 32,100, 62.1–1175, 1.1–57, 61.6–620, 0.4–223, 16.6–4380, 1.2–94.7, and 0.03–1.4 μg g−1 dw, respectively. The total contents of 17 PCDD/Fs varied from 0.1128 to 127.7939 μg g−1 dw, and the 2,3,7,8-TeCDD toxic equivalents (TEQ) of PCDD/Fs ranged from 0.009 to 6.177 μg g−1 dw. PCDF congeners were the main contributor to the TEQ. The leachate of the fly ash showed biotoxicity to C. pyrenoidosa. A significant correlation was found between the Cd and EC50 values. Further research is required to investigate the environmental impact of the various pollutants in the fly ash. 相似文献
17.
Yayintas OT Yilmaz S Turkoglu M Dilgin Y 《Environmental monitoring and assessment》2007,127(1-3):389-397
Waste water pollution of industrial areas can answer for the serious consequences of one of the most important environmental
threats to the future. In this study, inductively coupled plasma-atomic emission spectrometry method (ICP-AES) is proposed
to determine heavy metals (Pb, Cu, Cd, Cr, Zn, Al, Fe, Ni, Co, Mn) and major elements (Ca, Mg) in waste water of Kocabas Stream.
The concentration of metals in the waste water samples taken from 9 different stations (St.) in Biga-Kocabas Stream in November
2004 (autumn period) were determined after simple pretreatment of samples by the proposed ICP-AES method. An analysis of a
given sample is completed in about 15 min for ICP-AES the method. The results of heavy metals concentrations in waste water
were found between 0.00001–77.69610 mg l−1 by the ICP-AES technique. The concentrations of Pb, Cd, Cu, Zn, Cr, Al, Fe, Mn, Ni, Co, Mg and Ca 0.00001 (St.3,6,7) – 0.0087
mg l−1 (St.9), 0.00001 (St.4-7) – 0.0020 mg l−1 (St.8), 0.00001 (St.1,3-7,9) – 0.0041 mg l−1 (St.2), 0.0620 (St.2) – 0.2080 mg l−1 (St.3), 0.0082 (St.6) – 0.2290 mg l−1 (St.8), 0.3580 (St.2) – 1.7400 mg l−1 (St.3), 0.2240 (St.1) – 0.6790 mg l−1 (St.3), 0.0080 (St.1) – 1.5840 mg l−1 (St.3), 0.0170 (St.3) – 0.0640 mg l−1 (St.2), 0.0010 (St.1,4,5,8) – 0.0080 mg l−1 (St.3), 5.0640 (St.9) – 5.2140 mg l−1 (St.1) and 43.3600 (St.2) – 77.6961 mg l−1 (St.9), respectively. Also we measured environmental physicochemical parameters such as temperature, salinity, specific conductivity,
total dissolved solid (TDS), pH, oxidation and reduction potential (ORP), and dissolved oxygen (DO) in the waste water at
sampling stations. 相似文献
18.
Seasonal variation of the concentrations of trace metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn) were measured by ICP-AES
in the water and sediment from the Saricay Stream, Geyik Dam and Ortakoy Well in the same basin. Comparisons between trace
metal concentrations in water and sediment in three sources (Stream, Dam and Well) were made. The concentrations of a large
number of trace metals in the water and sediment were generally higher in the Stream than in the Well and Dam, particularly
in summer. Trace metal concentration ranges in sediments of the Saricay Stream and its sources showed very wide ranges (as
mass ratio): Co: 5–476 μg g−1, Cr: 15–1308 μg g−1, Cu: 7–128 μg g−1, Fe: 1120–13210 μg g−1, Mn: 150–2613 μg g−1, Ni: 102–390 μg g−1, Pb: 0.7–31.3 μg g−1 and Zn: 18–304 μg g−1, whereas Cd was not detected. Trace metal concentration ranges found in waters were: Co: 9.5–20.7 μg L−1, Cr: 20.3–284 μg L−1, Cu: 170–840 μg L−1, Fe: 176–1830 μg L−1, Mn: 29.3–387 μg L−1, and Ni: 4.3–21.9 μg L−1. Among the trace metals studied, Cd and Zn in two seasons and Pb in winter were usually not detected or in the recommended
levels. In addition, Cd was not detected in the sediment during the winter season. The analysis of variance (one-way ANOVA)
and correlation matrix was employed for the sediment and water samples of the two field surveys (summer and winter) comparison.
The three sources showed differences in metal contents. The metal levels in sediments displayed marked seasonal and regional
variations, which were attributed to anthropogenic influences and natural processes. In the Saricay Stream, high values of
metals during the dry season showed an anthropological effect from small industry firms, e.g.: an olive mill and a dairy farm
or water dilution during summer seasons. Finally, the pollution in this basin probably originated from small industrial, low
quality coal-burned thermal power plants, and particularly agricultural and domestic waste discharges. 相似文献
19.
Use of industrial and wastewater for irrigation is on the rise in India and other developing countries because of scarcity
of good-quality irrigation water. Wastewaters contain plant nutrients that favour crop growth but leave a burden of heavy
metals which can enter the food chain and is a cause of great concern. The present study was undertaken on the long-term impact
of irrigation with treated sewage water for growing vegetables and the potential health risk associated with consumption of
such vegetable. Treated sewage water (TSW), groundwater (GW), soil and plant samples were collected from peri urban vegetable
growing areas of Northern India (Varanasi) and analysed to assess the long-term effect of irrigation with TSW on Cd, Cr, Ni
and Pb build-up in soils and its subsequent transfer into commonly grown vegetable crops. Results indicate that TSW was richer
in essential plant nutrients but contained Cd, Cr and Ni in amounts well above the permissible limits for its use as irrigation
water. Long-term application of TSW resulted in significant build-up of total and DTPA extractable Cd, Cr, Ni and Pb over
GW irrigated sites. TSW also resulted in slight lowering in pH, increase in organic carbon (1.6 g kg − 1) and cation exchange capacity (5.2 cmol kg − 1). The tissue metal concentration and relative efficiency of transfer of heavy metals from soil to plant (transfer factor)
for various groups of vegetables were worked out. Radish, turnip and spinach were grouped as hyper accumulator of heavy metals
whereas brinjal and cauliflower accumulated less heavy metals. Health risk assessment by consumption of vegetables grown with
TSW indicated that all the vegetables were safe for human consumption. However, significant accumulation of these heavy metals
in soil and plant needs to be monitored. 相似文献
20.
Metal fractionation provides information on mobility and stability of various metal species which can be used to evaluate
the movement of such metals in soils. The effect of wastewater irrigation on the fractions, spatial distribution, and mobility
of cadmium (Cd) and zinc (Zn) was investigated in five urban gardens in Kano, Nigeria. Concentration of total Zn in the surface
soils (0–20 cm) ranged from 121 to 207 mg kg − 1 while Cd concentration was 0.3–2.0 mg kg − 1. Speciation of both heavy metals into seven operationally defined fractions indicated that the most reactive forms extracted
with ammonium nitrate and ammonium acetate, also considered as the bioavailable fractions, accounted for 29–42% of total Cd
and 22–54% of total Zn, respectively. The weakly bound fractions of Cd and Zn reached up to 50% of the total Cd and Zn concentrations
in the soils. Such high proportions of labile Cd and Zn fractions are indicative of anthropogenic origins, arising from the
application of wastewater for irrigation and municipal biosolids for soil fertility improvement. Thus, given the predominance
of sandy soil textures, high concentrations of labile Cd and Zn in these garden soils represent a potential hazard for the
redistribution and translocation of these metals into the food chain and aquifer. 相似文献