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Showing papers on "Trace metal published in 1975"


Journal Article
TL;DR: In this paper, the ability of the sludge to move soluble metal species from wastewa ter and the affinity of the biological mass for selected heavy metals was investigated using a cation exchange technique, previously used by soil scientists to investigate metal-organic complexation in soil and its extracts.
Abstract: MANY MUNICIPAL ACTIVATED SLUDGE plants receive combined wastewater containing heavy metals. These metals typically include copper, zinc, nickel, and cadmium and originate predominantly from industrial dischargers. Historically, there has been little concern for the pres ence of these metals in the wastewater, as long as they were at subtoxic levels. In creasingly stringent effluent regulations, to gether with recent indications of the detri mental effects of trace metal discharges on the receiving environment and its biota, have resulted in a need to assess the inter action and removal efficiency of heavy metals within the activated sludge process. There are numerous reports in the tech nical literature of soluble metal removal through the activated sludge process. Stones1_5 reported that activated sludge treatment reduced influent levels of iron, copper, lead, nickel, and zinc by 30 to 90 percent. Barth et al.6*7 reported removals comparable with those found by Stones for copper, nickel, and zinc. In studying the toxic effects of mercury on activated sludge, Ghosh and Zugger8 observed 51 to 58 per cent removal of the soluble mercury that was added to the mixed liquor and sug gested as a mechanism of removal either adsorption or incorporation into the cells. The complex and variable nature of com bined wastewater and activated sludge su pernatant suggests that a variety of soluble metal species may exist within the process. These may include, in addition to the free metal ion, complex species involving both organic and inorganic ligands. Because relatively little is known about the physical-chemical interactions between the activated sludge process and soluble metal ions, this study was undertaken to investigate the ability of the sludge to re move soluble metal species from wastewa ter and the affinity of the biological mass for selected heavy metals. The degree to which metal ions associate with the sludge determines the extent of reduction of solu ble metal in the supernatant and the con sequent effluent metal concentrations. A strong affinity between the sludge and metal, resulting in accumulation of the metal within the sludge, may enhance toxic effects that are not easily alleviated if the metal is tightly bound into the sludge. These toxic properties may carry over to digestion processes receiving excess sludge. Determination of sludge and supernatant association constants with heavy metals provides a useful tool for the assessment of physical-chemical interaction between the metal and the sludge. A cation-exchange technique, previously used by soil scientists to investigate metal-organic complexation in soil and its extracts, was used to deter mine the "apparent" stability constants of metal-supernatant and metal-sludge asso ciation.

134 citations


Journal ArticleDOI
TL;DR: In this paper, the adsorption of copper and cobalt from aqueous solution on to illite and other substrates has been studied as a function of pH, solution composition and solid phase concentration.

98 citations


Journal ArticleDOI
TL;DR: For example, in the vicinity of the River Tamar and of the metamorphic aureole around Dartmoor, the authors of as discussed by the authors found significantly higher concentrations of arsenic and heavy metals in soils contaminated by mining, smelting and mineralisation compared with those from nearby control areas.

87 citations


Journal ArticleDOI
TL;DR: In this article, a detailed comparison of the cadmium, copper and zinc contents of Fucus vesiculosus at various sites in the Bristol Channel with a detailed investigation of the dissolved trace metal concentrations to which they are subjected, demonstrates the passive nature of the accumulation.

87 citations



Journal ArticleDOI
TL;DR: In this article, the trace metal content of bottom sediments and waters of five estuaries and their catchment drainage, representing both contaminated and relatively uncontaminated environments, were investigated.

64 citations



Journal ArticleDOI
TL;DR: Anodic stripping voltammetry (ASV) using the thin-film mercury electrode was shown to be a successful technique for the determination of total (free plus complexed) trace metal concentrations in various types of aqueous sample as mentioned in this paper.

53 citations


Journal ArticleDOI
TL;DR: The eggs of two groups of oysters containing significantly different levels of copper and cadmium were collected, the eggs were collected and trace metal contents measured, and no conclusion could be made about the transfer of these three metals from adults to eggs of oyster.

37 citations



Journal ArticleDOI
TL;DR: In this paper, the trace elements of biological concern: Cr, Co, Cu, Cd, Ni, Pb, Hg, Zn and Ag were investigated in the sediments of the most important coastal steams in Israel.
Abstract: Nine trace elements of biological concern: Cr, Co, Cu, Cd, Ni, Pb, Hg, Zn and Ag were investigated in the sediments of the most important coastal steams in Israel. All of these are subjected to some degree of domestic and/or industrial sewage input with the consequent liability of contamination by trace metals. The Ayyalon, Gadura, Qishon and locally the Hadera rivers contain sediments exhibiting severe pollution effects. There is a danger of infiltration through the soils into the groundwaters as well as exposing nearshore fauna to sediments contaminated by possibly toxic trace metals. The other rivers bear smaller levels of trace metals; however, an increase of the Pb and the Zn levels occurs near major highways.

Journal ArticleDOI
TL;DR: Results are presented for the levels of chromium, cobalt, copper, iron, manganese, nickel and zinc in 190 cured meat samples.
Abstract: Results are presented for the levels of chromium, cobalt, copper, iron, manganese, nickel and zinc in 190 cured meat samples. The average and range of each of the trace metals, in parts per million, are as follows: chromium 0.06 (n.d.-1.27); cobalt 0.06 (n.d.-0.41); copper 0.73 (n.d.-1.80); iron 16.6 (4.0–52.4); manganese 0.26 (0.01–1.15); nickel 0.19 (n.d.-1.04); zinc 24.2 (6.9–56.6).

Journal ArticleDOI
TL;DR: In this article, ten soils were leached with a dilute solution of AICI3, and FeCl2 adjusted with HCl to pH 3.0, and the effluents were analyzed for eight trace metals as well as pH, to determine the maximum contribution of the soils to the trace metal burden of the soil solution.
Abstract: Ten soils were leached with a dilute solution of AICI3, and FeCl2 adjusted with HCl to pH 3.0. The effluents were analyzed for eight trace metals as well as pH, to determine the maximum contribution of the soils to the trace metal burden of the soil solution. This contribution was correlated with various soil properties to evaluate the controlling factors on the elution of certain metals. Measurable quantities of Mn, Co, Zn, Ni, Cu, and Cr were found in the soil leachates; Cd and Pb were infrequently detected. The important soil properties describing the amounts of the elements leached were the total metal originally present, the total amount of Mn, and the percentage of free iron oxides.



Book ChapterDOI
01 Jan 1975
TL;DR: In this article, the authors identify the major problems in understanding trace metals and their transport in the atmosphere is distinguishing between the natural and anthropogenic components, which is often relatively easy to do in or near urban areas, but becomes increasingly difficult on a regional and global scale.
Abstract: Unlike the heavier organohalogen compounds such as DDT and PCBs, atmospheric trace metals have significant natural as well as anthropogenic sources. Thus one of the major problems in understanding trace metals and their transport in the atmosphere is distinguishing between the natural and anthropogenic components. While this is often relatively easy to do in or near urban areas, it becomes increasingly difficult on a regional and global scale.

Journal ArticleDOI
TL;DR: In this article, the Buffalo River sediments were sampled over 130 mi in northern Arkansas and the results were analyzed by atomic absorption for Na, K, Mg, Ca, Zn, Cd, Pb, Fe, Co, Cr, Ni, Cu, Mn and K.
Abstract: Sediments were sampled over 130 mi of the Buffalo River in northern Arkansas. Aqua regia extracts of the minus 95 mesh fraction of the sediments were analyzed by atomic absorption for Na, K, Mg, Ca, Zn, Cd, Cu, Pb, Fe, Co, Cr, Ni, and Mn. Zirconium was determined by X-ray fluorescence. There was a general decrease downstream in Fe, Cu, Cr, Ni, Mn, Pb, K, and Na as the drainage area increased in carbonate rock and decreased in shale. The elements Mg, Ca, Zn, and Cd increased in sediments downstream. The sediments are mainly quartz and chert grains. These grains are apparently coated with hydrous iron oxide which acts as a sorbent for most of the metals and is a dominant transport mechanism for acid extractable Co, Cr, Ni, Cu, Mn, and K. Other acid extractable metals, particularly Mg, Ca, Zn, Cd, and Pb are mostly in clastic grains. Cadmium to zinc ratios in the sediments and in ore minerals of the area are similar. The ore metals of the drainage area are Zn, Pb, and Cu. The acid extractable amounts of these metals in the sediments rise and fall with the extractable amounts of Ca plus Mg in the sediments, indicative of the favorite host rock, dolomite. Tributaries are sites of rapid rise and fall of metal values within a few miles from background to anomalously high values and return to background.

Journal ArticleDOI
TL;DR: The present work was initiated when it was noticed that plasma metal content seemed altered in several species exposed to high-frequency band fields.
Abstract: While present standards for exposure to radio frequency (rf) fields are largely based on calculation of the thermal insult that results from exposure to such fields, the nature of biochemical changes induced by the thermal insult is of practical importance in determining the extent of exposure damage. Earlier work has been summarized by Michaelson.' An effect on cell synchrony was described by Prince and associate^.^ The present work was initiated when it was noticed that plasma metal content seemed altered in several species exposed to high-frequency band fields.


Journal ArticleDOI
TL;DR: The second Research Triangle Conference on Heavy Metals in the Environment was held to further highlight the many diverse aspects of trace metal research currently being conducted by area scientists.
Abstract: The second Research Triangle Conference on Heavy Metals in the Environment was held to further highlight the many diverse aspects of trace metal research currently being conducted by area scientists. The biological effects of toxic trace metals in both marine and agricultural ecosystems as well as aspects of metal analysis, biochemistry, and toxicology were examined in the first phase of the conference. Research papers on trace metal analysis, biochemistry, and toxicology were presented on the second day of the conference.


01 Jan 1975
TL;DR: In this paper, the authors present an overview of the purpose and purpose of exploration in the field of sea water and their application in the area of bottom sediment analysis. But they do not consider the effects of bottom sea water on bottom sediment.
Abstract: ................................................. ix INTRODUCTION AND PURPOSE OF EXPERIMENT................ 1 LITERATURE REVIEW........................................ 4 1. Trace Metals in Sea Water..................... 4 2. Speciation in Sea Water....................... 6 3. Analytical Measurements in Sea Water........ 15 4. Soluble Trace Metal-Particulate Interactions 28 5. Analytical Characterization of Bottom Sediments....................................... 35 DESIGN OF THE EXPERIMENT................................ 38 EXPERIMENTAL.............................................. 42 RESULTS AND DISCUSSION.................................. 49 1. Characterization of Sea Water................. 49 2. Characterization of Bulk Sediment............ 65 3. Equilibrium Experiments....................... 71 SUMMARY................................................... 99 BIBLIOGRAPHY.............................................. 104