Neutron-activation analysis applied to copper ores and artifacts

Neutron activation analysis is used for quantitative identification of trace metals in copper. Establishing a unique fingerprint of impurities in Michigan copper would enable identification of artifacts made from this copper

Seasonal variation of some trace metal concentrations in some fish species on stretch of River Kubanni, Zaria

In a semi-urbanized stretch of river Kubanni, Zaria, seasonal variations of some tree metals (copper, zinc and lead) in fish species (Clarias sp., Tilapia sp and Alestes sp) were investigated over a period of eight months. Water and fish were sampled monthly, pooled separately and seasonal analysis of each trace determined using atomic absorption method. The concentration of each of the elements in water higher in the dry season than during the rainy season. The dry and rainy season concentrations of copper, zinc and lead were 6.85~c10.66 mu gg super(-1)&1.45~c1.10 mu gg super(-1); 2.13~c1.68 mu gg super(-1)&0.1 5~c0.05 mu gg super(-1); and 0.52~c0.50 mu gg super(-1) & 0.31~c0.14 mu gg super(-1) respectively. Similarly, all the three accumulated more zinc and lead in the dry season than during the rainy season. Tilapia species and to some extent, Alestes species being pelagic had a higher concentration of trace metals than Clarias species which is a bottom dwelling fish Tilapia species may therefore be a better indicator species than Clarias species for monitoring trace metals in water bodies. Reasons for the observed variations in the trace metals were discusse

Trace metal fractionation as a mean to improve on the management of contaminated sediments from runoff water infiltration basins

The management of stormwater sediment is a key issue for local authorities due to their pollution load and important tonnages. In view of reuse, e.g. for embankment, the environmental evaluation of these highly aggregated sediments requires studying trace metals fractionation and mobility. The distribution of trace metals (Cd, Cr, Cu, Ni, Pb, Zn) and their level of lability in three French stormwater sediments was determined using sequential and kinetic extractions (EDTA reagent) associated with mineralogical analysis and SEM observations. Using microanalysis, new data were acquired on the evolution of aggregate state during extractions and on its significant role in trace metals retention. Trace metals were, in particular, observed to be very stable in small aggregates (10-50 µm). The comparison of the two extraction methods pointed out that EDTA extraction was not convenient to evaluate the stable fraction of Cr, Ni and Zn. Moreover, the results were relevant for basins presenting similar trace metals sources, whatever the physicochemical conditions in basins. The results suggest that the management of stormwater sediments could be improve by a better knowledge of metal mobility, as far as chemical extractions could highlight the localisation of the mobile trace metals fraction. Treatment could be therefore avoided or specific treatment could be applied to a reduced volume of sediments

Size distributions of atmospheric particulate matter and associated trace metals in the multi-industrial city of Ulsan, Korea

Particulate matter (PM) was collected using micro-orifice uniform deposit impactors from a residential (RES) site and an industrial (IND) site in Ulsan, South Korea, in September-October 2014. The PM samples were measured based on their size distributions (11 stages), ranging from 0.06 ??m to over 18.0 ??m. Nine trace metals (As, Se, Cr, V, Cd, Pb, Ba, Sb, and Zn) associated with PM were analyzed. The PM samples exhibited weak bimodal distributions irrespective of sampling sites and events, and the mean concentrations of total PM (TPM) measured at the IND site (56.7 ??g/m3) was higher than that measured at the RES site (38.2 ??g/m3). The IND site also showed higher levels of nine trace metals, reflecting the influence of industrial activities and traffic emissions. At both sites, four trace metals (Ba, Zn, V, and Cr) contributed to over 80% of the total concentrations in TPM. The modality of individual trace metals was not strong except for Zn; however, the nine trace metals in PM2.5 and PM10 accounted for approximately 50% and 90% of the total concentrations in TPM, respectively. This result indicates that the size distributions of PM and trace metals are important to understand how respirable PM affects public health

Potential chemical time bombs in the Schelde estuary

The Schelde estuary is heavily polluted with many different (micro)pollutants. This results in high concentrations in the abiotic and biotic compartments of the Schelde estuary and in various effects. the present day suboxic and anoxic conditions in the upper estuary are probably responsible for the high distribution coefficients for some trace metals in the lower Schelde estuary (Western Schelde). a future reduction in discharges with a high biological oxygen demand will therefore not only result in higher oxygen concentrations, but probably also in lower distribution coefficients for trace metals in the Western Schelde. Simulations show that lower trace metal distribution coefficients will probably result in higher concentrations of dissolved (bioavailable) trace metals, even with substantially reduced discharge rates, due to the desorption of trace metals from resuspended bottom sediments

Geochemical-geophysical investigations, Fairbanks district

Trace element distribution in a subarctic valley in the Cleary Hill area of the Fairbanks gold district has been studied. Zinc and arsenic have been found excellent pathfinder elements for auriferous deposits. Methods of analysis for copper, lead, zinc, molybdenum, silver and arsenic as well as heavy metals are discussed. The University of Alaska method #2 has been improved, Terrain, slope, and frozen ground have little effect upon the distribution of trace elements associated with the Cleary H i l l vein. A new method for the determination of zinc using dilute acid is proposed. Analysis of geochemical data by trend surface procedures proved effective for localization of anomalies

Fate of trace metals in anaerobic digestion

© Springer International Publishing Switzerland 2015. A challenging, and largely uncharted, area of research in the field of anaerobic digestion science and technology is in understanding the roles of trace metals in enabling biogas production. This is a major knowledge gap and a multifaceted problem involving metal chemistry; physical interactions of metal and solids; microbiology; and technology optimization. Moreover, the fate of trace metals, and the chemical speciation and transport of trace metals in environments— often agricultural lands receiving discharge waters from anaerobic digestion processes— simultaneously represents challenges for environmental protection and opportunities to close process loops in anaerobic digestion.The authors acknowledge funding within the framework of the COST Action 1302 (‘European Network on Ecological Roles of Trace Metals in Anaerobic Biotechnologies’). GC is supported by a European Research Council Starting Grant (‘3C-BIOTECH; No. 261330).Peer Reviewe

Role of natural nanoparticles, imogolite and allophane, on the mobility of trace metals in soils from La Reunion Island

This research adresses the sensitive field of waste management in an insular context. The case of the Reunion Island bears some aggravating factors making the waste management an even more sensitive subject: 1) it is a small island with a fast growing population and associated activities 2) the agricultural soils (mostly andosols) have an elevated natural concentration of trace metals. An inexpensive form of waste management is to reuse agricultural- waste (especially pig manure) as fertilizer. However, reuse of waste, may modify physico-chemical conditions and trace elements can be released from the soils. The accuracy of the prediction of metal fluxes in soils will be greatly enhanced by a detailed knowledge of the pollutants' speciation, which controls their mobility, toxicity and ultimately their bioavailability. Although the trace metals Cu, Ni, Zn selected for this study because of their occurrence in the soils and wastes, may bind to numerous components of the soils (clays, Fe and Al oxides, organics), we chose to focus on 2 types of nanosized alumino-silicates: the tubular imogolites (2nm diameter) and the spherical allophane (3-5nm). The choice of these phases is justified by their high abundance in the andosols of the Reunion, and their suspected high reactivity arising from the presence of -SiOH and -AlOH at the surface of structures whose specific surface area can reach 700m2/g. Here we detail using a molecular approach the types of the binding mechanisms between pollutants and natural occurring nanoparticles. (Texte integral

Trends of labile trace metals in tropical urban water under highly contrasted weather conditions

International audienceThe spatio-temporal trend of trace metals (Cd, Co, Cr, Cu, Ni, Pb, and Zn) in a tropical urban estuary under the influence of monsoon was determined using diffusive gradient in thin films (DGT) in situ samplers. Three different climatic periods were observed: period 1, dry with dredging activity; period 2, intermediate meaning from dry to wet event; and period 3, wet having continuous rainfall. Conforming to monsoon regimes, these periods correspond to the following: transition from winter to summer, winter, and summer monsoons, respectively. The distinction of each period is defined by their specific hydrological and physico-chemical conditions. Substantial concentrations of the trace metals were detected. The distribution and trend of the trace metals under the challenge of a tropical climate were able to follow using DGT as a sensitive in situ sampler. In order to identify the differences among periods, statistical analyses were performed. This allowed discriminating period 2 (oxic water) as significantly different compared to other periods. The spatio-temporal analysis was then applied in order to distinguish the trend of the trace metals. Results showed that the trend of trace metals can be described according to their response to (i) seasonal variations (Cd and Cr), (ii) spatio-temporal conditions (Co, Cu, Ni, and Pb), and (iii) neither (i) nor (ii) meaning exhibiting no response or having constant change (Zn). The correlation of the trace metals and the physico-chemical parameters reveals that Cd, Co, Cu, and Cr are proportional to the dissolved oxygen (DO), Cd and Ni are correlated pH, and Zn lightly influenced by salinity