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Antimony as a Tracer of the Anthropogenic Influence on Soils and Estuarine Sediments
2001
Cal-Prieto, M. J. | Carlosena, A. | Andrade, J. M. | Martínez, M. L. | Muniategui, S. | López-Mahía, P. | Prada, D.
The aim of this work was to evaluate antimony (Sb) as apotentially valuable tracer of the anthropogenic impact on soilsand estuarine sediments. Antimony was determined in fifteenroadsoils from a medium-size city, La Coruña (NW of Spain);and twelve sediments from two estuaries (La Coruña and Ares-Betanzos). Sb determination was accomplished in a rapid andreliable way by directly measuring the solid samples with anautomatic ultrasonic slurry sampling-ETAAS device. Soil contentsranged from 0.29 to 8.81 μg g⁻¹. A relation between Sbconcentration and motor vehicle intensity was observed.Regarding estuarine sediments, Sb amounted from 0.22 to 1.51 μg g⁻¹, for the La Coruña estuary and 0.24 to 0.71 μg g⁻¹, forthe Ares-Betanzos estuary; higher Sb values were found forcoastal locations whereas lower contents corresponded to `inner'samples. In order to confirm these findings, other pollutantswere studied: As, Cd, Co, Cr, Cu, Ni, Pb, Zn, aliphatichydrocarbons (AH) and polycyclic aromatic hydrocarbons (PAH).These values, along with the Sb ones, were subjected tomultivariate studies intended to elucidate whether Sb correlated(and to what extent) to other well-known anthropogenic pollutants. Thus, Sb became associated to Cd, Cu, Pb and Zn in road soils and to As, Cu, Zn, PAH, Pb and unresolved hydrocarbons, in sediments.
Mostrar más [+] Menos [-]Distribution of Trace Elements in Tissues of Two Shrimp Species from Persian Gulf and Effects of Storage Temperature on Elements Transportation
2001
Pourang, N. | Amini, G.
This study is focussed on evaluation of temperature effectduring frozen storage on movement of trace elements in differenttissues (exoskeleton, carapace and abdominal muscle) of twocommercially important shrimp species (Penaeusmerguiensis and Metapenaues affinis). Moreoverrelationships between total length and sex of specimens with concentration of trace elements in selected tissues were assessed. Concentrations of Cd, Cr, Cu, Fe, Mn, Ni and Znin samples were determined by ICP-AES. Only in the case of Niand Zn sex related differences could be observed. With theexception of Cu, the trace metals distributed significantlydifferent between the tissues. The only significant differencesbetween species were found in bioaccumulation of Mn. Sizedependent relationship was observed only for Ni. Associationsbetween Mn and Fe were positively and highly significant in allthe cases. The levels of all the metals in muscle of the shrimpsfrom the studied region were comparable to other world areas. MeanCu and Zn levels in edible parts of M. affinis stored at–10 °C exceeded some existing guidelines, while the concentrations at –30 °C were somewhat lower than them.
Mostrar más [+] Menos [-]Common hydrophytes as bioindicators of nickel, chromium and cadmium pollution
2001
Zurayk, R. | Sukkariyah, B. | Baʻlabakkī, Ramzī
Twelve Mediterranean hydrophyte species collected inLebanon were evaluated for their potential asbioindicator species for heavy metal pollution innutrient cultures enriched with 1 ppm Cr, Ni and Cd.These were: Nasturtium officinale R.Br, Apium nodiflorum L., Veronica beccabunga L., Veronica anagallis aquatica L., Veronicalysimachioides L., Veronica anagalloides L., Mentha longifolia L., Mentha aquatica L., Mentha pulegium L., Potentilla reptansL., Mentha sylvestris L., and Cardamine uliginosa L.. Large variability in responseto exposure to the heavy metals was observed. Growthrates remained high during the experimental period,indicating that the plants were little affected by thepresence of the metal at the experimentalconcentration. Metal accumulation and bioconcentrationvaried within at least one order of magnitude, andranged from less than 10 to over 200. Cr waspreferentially accumulated in the roots. All speciesbut M. pulegium, P. reptans and V. anagallisaquatica accumulated and bioconcentrated sufficientCr to qualify as bioindicator species. Five of thespecies that accumulated Cr also accumulated Ni, withthe same partitioning into the root. These were: N. officinale, C. uliginosa sp., M. longifolia, M. aquatica and M. sylvestris, all of which mayalso be used as bioindicators of Ni pollution. Onlyone species, M. aquatica, accumulated Cdsignificantly, and may, therefore, be used as abioindicator for all three metals.
Mostrar más [+] Menos [-]The Effects of Urbanization on the Chemical Quality of Three Tidal Bayous in the Gulf of Mexico
2001
Lewis, Michael A. | Moore, James C. | Goodman, Larry R. | Patrick, James M. | Stanley, Roman S. | Roush, Thomas H. | Quarles, Robert L.
Water and sediment quality in threetidal bayous located near Pensacola, Florida, wereassessed during 1993–1995. The primary objective wasto determine the environmental condition of therelatively small urban bayous by comparing thechemical quality of the sediments and surface waterwith published guidelines and criteria developed toprotect marine life. Surface water concentrations ofmost potential toxicants such as heavy metals,organochloride pesticides, PAHs and PCBs were usuallybelow method detection limits. The major exception tothis trend was for copper which consistently exceededFlorida and National acute and chronic water qualitycriteria. Nickel, cadmium and chromium intermittentlyexceeded these criteria. Sediment contamination wassite-specific and chemically diverse. Theconcentrations of as many as 17 compounds exceededproposed Florida sediment quality assessmentguidelines indicating the potential for adversebiological effects. Nutrient concentrations, with oneexception, were below average levels found in otherFlorida estuaries. Seasonal variation in contaminantconcentrations for sediment collected from the samesampling station was less than an order of magnitude. The differences in the concentrations of the sameanalytes as measured for the multiple samplingstations located within the same bayou varied 1 to 2orders of magnitude and over 2 orders of magnitude forthe 20 sampling stations located in the three bayous. A within-bayou sediment contaminant gradient wasevident; sediment quality generally improved seaward.
Mostrar más [+] Menos [-]Interactions on the Soil-Rainfall System of a Lime-Stabilized Sludge as Surface Amendment
2001
Suárez, D. | Rendueles, M. | Díaz, M.
Sludge from a wastewater treatment plant can be applied to soil to make use of its fertilizing properties, neverthelessit is necessary to study all the effects of this deposition to ascertain any possible hazardous properties. Interactions among the soil, the water, and a lime-stabilized waste watersludge were studied, both in batch experiments, and in columnpercolation experiments. Firstly a physico-chemical characterization of the soil and the sludge used for the experiments was carried out. This analysis included pH, organic matter, cation exchange capacity, metals and cations.The kinetics and equilibrium of the sludge-water and leachate-soil systems were studied in batch experiments; thekinetics were fitted to a first order differential equation and distribution coefficients were found for the equilibrium.Experiments in columns (10 cm diameter × 50 cm height) were carried out with a bed of sludge over a bed of soil usingdifferent sludge/soil ratios and then 6 L of water (rainfall)was poured over the beds. Results showed good adsorption of Ca and a complete leaching of the aqueous phase of this ion afterpassing a volume of water equivalent to three volumes of the column. The concentration of heavy metals (Zn, Ni, Hg, Cd, Pb and Cr) in the leachates did not reach the admissible legal limits (Spanish and European regulations) in any case.
Mostrar más [+] Menos [-]Sewage Sludge Application on Soil: Effects on Two Earthworm Species
2001
Barrera, I. | Andrés, P. | Alcañiz, J. M.
Some biological effects of soilfertilisation with sewage sludge were investigated aftersoil reclamation in an opencast mining area. Two earthwormspecies (Allolobophora chlorotica chloroticaand Nicodrilus caliginosus meridionalis) inhabitingthe reclaimed soil were tested for their response to twohigh doses of sludge (75 and 150 g kg⁻¹ of dry sludgein dry sieved soil). The metal concentrations in thesludge amended soils were below that which worm mortalitywould be expected. Mean annual density of the earthwormswas higher in the plots where the sludge was applied (435and 335 ind. m⁻²) than in control (115 ind. m⁻²).We verified the accumulation of Cd and Zn by the twoearthworm species at any dose of sludge, and metalaccumulation was higher in N. caliginosus than inA. chlorotica. Zn, Pb, Cr, Cu and Ni were moreconcentrated in the earthworm egesta than in the bulk soil.
Mostrar más [+] Menos [-]Variation in Total and Extractable Elements with Distance from Roads in an Urban Watershed, Honolulu, Hawaii
2001
Sutherland, Ross A. | Tolosa, Christina A.
Roads play a major role intransporting sediment associated nonpoint sourcepollutants to urban stream networks via storm drains. In urban areas the relationship of erodible soil toroads may be of critical importance in controllingmetal contributions to roads. Two 50-m transects(Park and School) were investigated perpendicular toroads in Manoa basin, Oahu, Hawaii. Concentrations ofnine elements were compared to background control soillocations and to five supplemental samples from nearbyrecreational parks. Sediment from curbside areas ofroads (road deposited sediment) was collected as thestarting point of each transect, and subsequently soilwas sampled from two depths (0–2.5 cm and 7.5–10.0 cm)along the transects. Total and 0.5 M HCl extractableconcentrations were determined for aluminum (Al),calcium (Ca), chromium (Cr), copper (Cu), iron (Fe),manganese (Mn), nickel (Ni), lead (Pb) and zinc (Zn)using either inductively coupled plasma-atomicemission spectroscopy (ICP-AES) or flame atomicemission spectroscopy (FAAS). Ca, Cu, Pb and Znexhibited anthropogenic enhancement, with Pb and Znhaving the greatest enrichment in road sedimentfollowed by locations nearest the road. Copperdisplayed a narrower band of contamination than eitherPb or Zn, and this may reflect larger aerosolassociations and more rapid fall velocities. Lead andZn exhibited substantial decay in concentration at 50 m compared to the road sediment, but enrichment wasstill apparent. The positioning of a band of soilbetween the road-curb area and the sidewalk for thePark transect facilitated deposition and storage oftrace metals, and with subsequent erosion by splash orconcentrated flow this area can account for continuedtransport of contaminated sediment to adjacent roadsurfaces. On the other hand the School transect hadno soil directly beside the road, and the nearestsample from the road (5 m) displayed enrichment butsubstantially lower than the Park transect. Thesepreliminary data suggest that remobilization of soilstored metals in close proximity to roads cansignificantly prolong the environmental contaminationof urban road systems and eventually stream sediments.
Mostrar más [+] Menos [-]Organic Acids for the In Situ Remediation of Soils Polluted by Heavy Metals: Soil Flushing in Columns
2001
Wasay, S. A. | Barrington, S. | Tokunaga, S.
To compare the soil remediation effectiveness of saltsof weak organic acids with strongchelating agents, three soils of different textures,all polluted by heavy metals, were washed in a column,at optimum pH, with salts of weak organic acids,namely, citrate, tartarate or oxalate + citrate orchelating agents (EDTA or DTPA). For the clay loam,Cr, Mn, Hg and Pb were removed by citrate andtartarate at levels of 43 to 45, 37 to 41, 91 to 92and 75%, respectively. EDTA and DTPA effectivelyleached only Pb after 20 pore volumes. For the loam,citrate leached 98 and 89% of Cd and Pb after 20 porevolumes, respectively, while tartarate leached out 91and 87% of Cd and Pb. EDTA and DTPA removed 93 to97% of these metals after 20 pore volumes. For thesandy clay loam, 84 to 91, 73 to 84, 56 to 70 and 72to 81% of Cd, Cu, Pb and Zn were removedrespectively, by citrate and tartarate. EDTA and DTPAremoved 93 to 97% of these metals after 20 porevolumes. An in situ soil remediation simulation wasalso tested using the sandy clay loam in a tub. After12 hr of retention, the citrate solution washed 81, 82,73 and 90%, of Cd, Cu, Pb and Zn, respectively, aftersix pore volumes. EDTA and DTPA effectively removedall heavy metals, except for Hg, but also extractedlarge quantities of soil nutrients and pollute thesoil by being adsorbed on the soil particles. Thesalts of citrate and tartarate effectively removed theheavy metals from the three polluted soils whileleaching little macro-nutrients and improving soilstructure. Each soil reached C and B levels ofsoil-clean-up criteria after 10 to 20 pore volumes andwithin 10 to 15 hr of flushing.
Mostrar más [+] Menos [-]An Analysis of Soil and Plant (Taraxacum Officinale) Contamination with Heavy Metals and Polycyclic Aromatic Hydrocarbons (PAHs) In the Area of the Railway Junction Iława Główna, Poland
2001
Malawska, M. | Wiołkomirski, B.
Polycyclic aromatic hydrocarbon and heavymetal (Pb, Cd, Cu, Zn, Hg, Fe, Co, Cr, Mo) contentswere established in soil and plant samples collectedin different areas of the railway junction IławaGłówna, Poland. Soil and plant samples werecollected in four functional parts of the junction, i.e. the loading ramp, platform area, rolling stockcleaning bay and the railway siding. It was found thatthe PAH contamination of soil and plants was thehighest in the platform area and near the railwaysiding and lowest in the loading ramp and cleaning bayareas. The contamination exceeded control levels up toalmost twenty fold. The heavy metal contaminationpattern was different. The soil and plants were veryhighly contaminated in the cleaning bay and side trackareas while the loading ramp and platform areas wereless contaminated. A particularly high pollution levelwas observed for mercury in the cleaning bay area.Also lead, zinc and copper pollution levels wererelatively high in the cleaning bay and side trackareas. No significant increase in molybdenum contentwas observed in comparison with the control area.
Mostrar más [+] Menos [-]Trace Element Emissions from some Cement Plants in Turkey
2001
Kalafatoğlu, Ersan | Örs, Nuran | Sain Özdemir, Sibel | Munlafalioğlu, Ismet
The cement industry has been one of the major sources of air pollution in the past and the Turkish Air Quality Protection Regulation has issued limits also to trace elementemissions to minimise the polluting effects of this industrialsector. In the present study, dust samples were obtained isokinetically from 18 main stacks of 10 cement plants locatedin different geographical areas of Turkey. The samples were analysed for trace elements Hg, Cd, Cr, Pb, Ni, Se, Te, TI, V, Sb, Ba, Zn, Co, Sr, Cu, Bi, Mo, Be, and As. The results are presented both as concentration in the dust samples as well as emissions per unit production, and concentration inthe stack gas. The trace element emissions of the main stacksagree to great extent with the values given in the literature. On the other hand, the trace element emissions of the plants considered are well below the limits set in the Turkish Air Quality Protection Regulation.
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