Voltammetric method for the determination of Zn,Cd, Pb,Cu and Ni in interstitial water

To determine heavy metals in interstitial water from Baltic sea sediments a sampling method with subsequent voltammetric determination is described. Copper, lead, zinc and cadmium are determined in the UV-digested samples of interstitial water by differential pulse anodic stripping voltammetry while nickel is determined by adsorption voltammetry. The determination of five metals in one sample in a wide concentrations range is possible using a low cost apparatus. The profiles of the metal concentrations in interstitial water of subsequent layers of sediments, sampled from Puck Bay, Gdańsk Bay, the Bornholm area and the S?upsk area are presented.     

Voltammetric method for the determination of Zn, Cd, Pb, Cu and Ni in interstitial water

To determine heavy metals in interstitial water from Baltic sea sediments a sampling method with subsequent voltammetric determination is described. Copper, lead, zinc and cadmium are determined in the UV-digested samples of interstitial water by differential pulse anodic stripping voltammetry while nickel is determined by adsorption voltammetry. The determination of five metals in one sample in a wide concentrations range is possible using a low cost apparatus. The profiles of the metal concentrations in interstitial water of subsequent layers of sediments, sampled from Puck Bay, Gdask Bay, the Bornholm area and the Supsk area are presented.     

Metal Concentrations in Soils and Sediments in Southwest Louisiana

ABSTRACT

Soils and sediments represent concentrated reservoirs for metals that serve as sinks for introduced trace metals or can become environmental sources. The coastal zone of Louisiana provides a “living laboratory” to investigate the mechanisms of transport, deposition, and dissolution of trace metals into this fragile environment. Common trace metals determined and their range of concentrations in soil and sediments are chromium (10-30 (parts per million) (ppm)), copper (10-25 ppm), iron (0.6-2.1 %), manganese (200-600 ppm), nickel (6-20 ppm), lead (8-20 ppm), and zinc (30-55 ppm).     

Use of atomic absorption spectrometry for the determination of metals in sediments in south-west Louisiana

The relatively recent introduction of atomic absorption spectrometry has produced a rapid and relatively inexpensive method for the determination of metal concentrations in a wide variety of samples. One such application is in the determination of metal concentrations in soils and sediments. Soils and sediments represent concentrated reservoirs for these metals that serve as sinks for introduced trace metals or can become environmental sources. The coastal zone of Louisiana provides a ‘living laboratory’ to investigate the mechanisms of transport, deposition, and dissolution of trace metals into this fragile environment. Investigations done in the coastal zone have found trace metals tend to concentrate near pollution inputs and sources and have not migrated to or significantly impacted the coastal zone of Louisiana. Common trace metals determined and their range of concentrations in coastal soil and sediments are chromium (10–30 ppm), copper (10–25 ppm), iron (0.6–2.1%), manganese (200–600 ppm), nickel (6–20 ppm), lead (8–20 ppm), and zinc (30–55 ppm).     

Atomic absorption spectrometric determination of chromium, copper, lead, mercury, and zinc in sediments collected in Bayou d'Inde, southwestern Louisiana

The concentrations of the metals chromium (Cr), copper (Cu), lead (Pb), mercury (Hg), and zinc (Zn) were determined in sediment cores taken from Bayou d'Inde in southwestern Louisiana. Previous studies had reported elevated concentrations of these trace metals in sediments along this waterway. The current study, conducted more than a decade later, was designed to determine if these metals had migrated from the areas of highest concentrations. Concentrations as high as 400 mg/kg for Cr, 1100 mg/kg for Cu, 10 mg/kg for Hg, and 600 mg/kg for Pb and Zn were found. Areas of high concentrations of metals were isolated within a distance of about 1 km from the most highly contaminated areas in the bayou. Low concentrations of metals were found at the mouth of the bayou. Estimated sedimentation rates of 0.67-1.2 cm/yr were based on the burial of the sediments originally studied. The concentrations of the metals studied remained high and were also highly localized, both spatially and temporally.     

Bestimmung von Metallen in Flußschlämmen mit Hilfe der Röntgenfluorescenz. Bedeutung für die Praxis

The occurrence of metals in the sediments of the Rhine basin was investigated with the aid of X-ray fluorescence. In addition to trace metals such as zirconium, strontium and rubidium which are encountered in non-varying concentrations, the heavy metals copper, lead and, in particular, zinc were found to occur in concentrations that vary considerably from one region to the other. Concentrations beyond the normal background limits are due to influent waste water. Besides the easy determination of metal traces, X-ray fluorescence permits also deductions on the density and, consequently, the mineralogical composition of the sediments.     

Extraction and determination of iron as the bathophenanthroline complex in high-purity niobium, tantalum, molybdenum and tungsten metals

A spectrophotometric method for determining iron in the range 0·001–0·125% in high-purity niobium, tantalum, molybdenum and tungsten metals is described. After sample dissolution and reduction of iron to the bivalent state with ascorbic acid and hydroxylamine hydrochloride, the red complex formed between iron^II and bathophenanthroline (4,7-diphenyl-1,10-phenanthroline) is extracted into n-arnyl alcohol and the absorbance of the resulting extract is determined at 536 mμ. Interference from copper is eliminated with thiourea. Cobalt, cadmium, nickel, manganese and zinc also interfere but the amounts of each of these impurities present in the four high-purity metals described are so low that their interference effects are negligible in the proposed method. Highly reproducible and precise results can be obtained with careful control of the pH during reduction and extraction.     

Matrix-Effekt und Korngrößenverteilung bei der Röntgenfluorescenzanalyse von Feststoffen der Gewässer

The intensity of the fluorescence of heavy metal traces, such as zinc, in waters can be described as a function of grain size distribution. Contrary to that of pure metals, it increases with grain size. For a parameter, the sample component in the grain diameter range below 6 μm is suited best. In the sediments of waste polluted waters, the same parameter is frequently found in close correlation to the zinc content of the samples. The analytical and practical consequences are discussed in the present paper.     

Assessment of trace metals contamination in estuarine sediments using a sequential extraction technique and principal component analysis

Fractionation of the metals Cd, Cr, Cu, Ni, Pb and Zn in sediments was performed for samples collected from eight locations in the Poxim river estuary of Sergipe State, northeast Brazil, using the 3-stage sequential extraction procedure proposed by the European Community Bureau of Reference (BCR). The extraction method was found to be satisfactory for analysis of certified reference material BCR-701, with recovery values ranging from 85% (Cu) to 117% (Cr). The detection limits obtained were 0.001 to 0.305 µg g^− 1. Zn exhibited greatest mobility and bioavailability, indicative of anthropogenic sources, while Cr was mainly found in the residual fraction and could be used as an indicator for the contribution from natural sources. Cd, Cu, Ni and Pb were associated with the oxidizable fraction, and Pb, Cr and Ni with the reducible fraction. Principal component analysis (PCA) clearly separated the metals into three groups: I (Zn); II (Pb); III (Cd, Cu, Cr and Ni). These groupings were mainly due to different distributions of the metals in the various fractions, in sediments from the different locations. Risk assessment code (RAC) analysis indicated that although the metals presented a moderate overall risk to the aquatic environment, nickel showed a low risk (RAC < 10%) at three sites, while zinc presented a high risk (RAC > 30%) at four other sites.     

Determination of trace metals in sea water by chelex-100 or solvent extraction techniques and atomic absorption spectrometry

Determinations of cadmium, lead, nickel, copper and zinc in sea water are discussed. Two different methods of preconcentration are compared: the trace metals are preconcentrated either by extraction with ammonium pyrrolidinedithiocarbamate/diethylammonium diethyldithiocarbamate into freon followed by back-extraction into nitric acid, or by collection on a Chelex-100 resin followed by elution with nitric acid. Cd, Pb, Ni, and Cu are determined by graphite-furnace atomic absorption spectrometry, while zinc is determined by flame atomic absorption spectrometry. The comparison of methods shows that cadmium can be determined accurately whereas results for the other trace metals may be biased by reagent contamination in the Chelex-100 method. Recovery data are given for both methods of preconcentration. Filtering experiments with Chelex-100 method are described. Results are compared for sea-water samples preconcentrated immediately after sampling and some weeks after sampling, with only freezing for preservation. The present results are consistent with other recent work. The importance of blank values is discussed.     

Chemical speciation and contamination assessment of Zn and Cd by sequential extraction in surface sediment of Klang River, Malaysia

The concentration and chemical speciation of Cd and Zn as well as total organic carbon (TOC) were studied in surface sediments from 21 stations along Klang River. Sequential extraction technique (SET) was applied to assess the four (exchangeable, acid-reducible, oxidisable-organic and residual) fractions in surface sediment. And also, to obtain an overall classification of cadmium and zinc pollution in this area. This investigation was the first study on the basis of the chemical speciation of Cd and Zn in surface sediments of the Klang River. The total concentrations of metals were ranged (0.60–2.26 µg g^{− 1}) for Cd and (33.26–268.24 µg g^{− 1}) for Zn. The chemical speciation of Cd and Zn in most sampling stations were in the order of residual > acid-reducible > oxidisable-organic > exchangeable, and it showed that the Zn in Klang River surface sediments existed in the nonresistant fractions, whilst Cd existed in the resistant fraction. The degree of surface sediments contamination was determined for individual contamination factors (ICF) and global contamination factor (GCF). The result of ICF and GCF values showed that those stations located vicinity of municipal area had high potential risk to fauna and flora of the Klang River. The relationship between the concentration of cadmium and zinc at the oxidation-organic fraction with TOC in surface sediment was identified. The results showed that TOC had a positive function to complex with Cd and Zn in the surface sediment of Klang River.     

Extraction—spectrophotometric determination of traces of thallium in lead,cadmium, indium and zinc metals with tri-n-octylamine

A sensitive spectrophotometric method is described for the determination of thallium in lead, cadmium, indium and zinc metals. Optimal conditions have been established for the extraction and determination of thallium. Thallium is extracted as its bromo complex with tri-n-octylamine and then converted to an iodo complex, the absorbance of which is measured at 400 nm. As little as 1 p.p.m. of thallium in lead, cadmium and zinc metals, and 2 p.p.m. of thallium in indium metal can be determined.     

Determination of traces of thallium in zinc and cadmium metals and process solutions by atomic-absorption spectrophotometry after extraction with di-isopropyl ether and reductive stripping

The bromo-complex of thallium(III) is extracted into di-isopropyl ether and reductively stripped into sodium sulphite solution, which is then analysed for thallium by atomic-absorption spectrophotometry. Thallium in zinc and cadmium metals and process solutions can be determined by this method.     

Combining multivariate analysis and geochemical approaches for assessing heavy metal level in sediments from Sudanese harbors along the Red Sea coast

Multivariate statistical analysis and geochemical approaches were exploited for the assessment of the level of some heavy metals (Mn, Fe, Ni, Cu, Zn and Pb) in sediments from Sudanese harbors along the Red Sea coast. Principal component analysis, as a multivariate statistical analysis approach, was applied to identify contribution sources by heavy metals in sediments. While a single source (crustal) was recorded in the bulk sediments and coarse sediment grains (grain-size 1000-500 µm), two sources (crustal and anthropogenic) were recorded in fine sediment grains (grain-size < 500 µm). Furthermore, enrichment factor (EF), as a geochemical approach, appointed polluted sites by heavy metals in the study area. Based upon a previous study addressed the interpretation of EF values, minor to moderate anthropogenic enrichment were recorded in sediments from some sites in the study area. The main anthropogenic activities that believed to be the major sources of pollution by heavy metals in the study area are discharges from oil refinery, industry, shipping activity and domestic waste. Hierarchical cluster analysis (HCA), as another multivariate statistical analysis approach, was applied for the concentrations of heavy metals in bulk sediments to group sediments according to their mineralogical composition. The output of HCA is that sediments from the Port-Sudan harbor can be divided mainly into three areas — east, west and south. For the Sawakin harbor, no apparent trend for the spatial distribution of heavy metals in sediments was recorded.     

Flow injection and microwave-oven sample decomposition for determination of copper,zinc and iron in whole blood by atomic absorption spectrometry

A simple and rapid method is proposed for the determination of copper, zinc and iron in whole blood. The injected sample is mineralized in the flow system on passage through a microwve oven and the metals are determined by atomic absorption spectrometry. Prior sample destruction or removal of organic material prior to injection is not necessary. The required volumes for each analysis are 90, 60 and 100 μl for copper, zinc and iron, respectively. The relative standard deviations were less than 3% in all cases. There was good agreement between the results obtained with the flow-injection method and those attained by conventional spectrophotometric measurements.     

Dithlzone extraction and flame atomic absorption spectrometry for the determination of cadmium,zinc, lead,copper, nickel,cobalt and silver in sea water and biological tissues

The method previously described for the determination of Cd, Zn, Cu, Ni and Co in sediments has been adapted for the determination of these metals, and lead and silver in sea water and biological tissues. For sea water the only treatment preceding extraction is pH adjustment; biological tissues are digested in nitric and perchloric acids and the residue taken up in dilute hydrochloric acid prior to pH adjustment and extraction. The method is sufficiently sensitive to allow Cd, Zn, Cu and Ni to be determined in all sea waters, Co and Ag in coastal waters, but Pb only in polluted water.     

Heavy metals in marine sediments from the Mar Piccolo of Taranto (Ionian Sea, southern Italy)

Heavy metals concentrations (Cd, Cu, Hg, Pb, Sn and Zn) have been determined monthly in surface sediments from the Mar Piccolo in Taranto (Ionian Sea, Southern Italy. a semi-enclosed marine basin very important from a mussel-culture point of view. In sediments, sulphides, percentage of organic carbon and redox potential were also determined to show possible correlations between metals levels and redox characteristics of marine sediments. Analytical results, elaborated by multivariate statistical techniques, confirm that sediments collected in the first inlet of Mar Piccolo, where shipbuilding activities are present, have a contamination level greater than those collected in the second inlet. For each metal, the geoaccumulation index (Igeo) has been calculated as criterion to evaluate both pollution levels and metals enrichment in examined sediments: Igeo values confirm that the first inlet is an moderately polluted area from Hg and Pb. In any case, high sulphide concentrations and negative values of redox potentials bring to a conclusion that metals are present in sediments, mainly as insoluble sulphides and then as not bioavailable compounds for filter feeders organisms such as mussels.     

Simultaneous determination of traces of iron, cobalt, nickel, copper, mercury and lead in water by energy-dispersive x-ray fluorescence spectrometry after preconcentration as their piperazino-1,4-bis(dithiocarbamate) complexes

A bidentate chelating agent has been proposed to preconcentrate seven metal ions dissolved in an aqueous sample for their simultaneous determination using energy-dispersive x-ray fluorescence spectrometry. The metal ions are precipitated as their polymeric piperazino-1,4-bis(dithiocarbamate) chelates, which are then collected by vacuum filtration on a Millipore membrane filter for direct examination by x-ray fluorescence analysis. Iron, cobalt, nickel, copper and zinc are determined by means of their K x-rays and mercury and lead by means of their L x-rays. A detection limit in the μg1⁻¹ range can be achieved for all metals tested in 250-ml water samples with a counting time of 600 s. Effective precipitation of all metals occurs at pH 6–7. The recoveries of eight analyses of the metals in a multielement standard using the proposed method ranged from 97 to 105% and the precision ranged from 2.3 to 3.1%. High concentrations of calcium and magnesium do not interfere with the method. The method is simple, sensitive and accurate, and has been used for the simultaneous determination of the seven metals under study in environmental samples and synthetic mixtures.     

Tracing the sources of stream sediments by Pb isotopes and trace elements

The objective of this research is to trace the sources of stream sediments in a small watershed influenced by anthropogenic and lithogenic origins identified by the spatial distributions and temporal variations of stream sediments using geochemical interpretation of the stable and radiogenic isotopes, major components, and heavy metals data and principal component analysis. To know the effects of both present and past mining, the stream sediments were sampled at the stream tributaries and sediment coring work. The spatial distributions of heavy metals clearly showed the effects of Cu and Pb?CZn mineralization zones at the site. Anthropogenic Pb was elevated at the downstream area by the stream sediments due to an active quarry. The results of principal components analysis also represent the effects of the stream sediments origins, including anthropogenic wastes and the active quarry and lithogenic sediment. Anomalous Cu, indicating the effect of past Guryong mining, was identified at the deep core sediments of 1.80?C5.05?m depth. The influence of active quarry was shown in the recently deposited sediments of <1.50?m depth, which was proved by the profiles of radioactive ²¹⁰Pb and stable Pb and Sr isotopes. This study suggests that the chemical studies using radiogenic and stable isotopes and heavy metals and multivariate statistical method are useful tools to discriminate the sources of stream sediments with different origins.