Variations In Trace Metal Concentrations Research Articles

Variability of Trace-Metal Concentrations Within and Between Colonies of Pocillopora damicornis

Variations of cadmium, lead, copper, nickel and chromium concentrations in tissues and skeletons of the scleractinian coral Pocillopora damicornis were measured to provide information for designing bio-assay surveys involving this organism. Intra-colony variations were measured using multiple portions from individual colonies, and inter-colony variations were measured using single portions from different colonies of a coral community. We found that specific metals partitioned differently into tissue and skeletal parts, possibly because selectivity for each metal differed due to biochemical utility or toxicity. Intra-colony variations in metal concentrations were inconsistent, and skewed distributions of tissue-metal concentrations were sometimes observed. Overall, the application of tissues for heavy-metal bio-assays is compromised by inconsistent intra-colony variation, and the substantial material needed to represent tissue-biomass. In contrast, small replicate samples of skeleton can be collected from a colony, allowing representation of intra-colony metal variation with minimal damage to the organism.

Temporal and Spatial Variations of Trace Metal Concentrations in Oysters from the Patuxent River, Maryland

Concentrations of copper (Cu), silver (Ag), and cadmium (Cd) in eastern oysters (Crassostrea virginica) from the upper Patuxent River estuary analyzed since 1986 (Cd since 1991) were high relative to concentrations in other sites in the United States analyzed by the National Oceanic and Atmospheric Administration National Status and Trends program. Patuxent River oysters had above average concentrations of Ag and Cu, and unusually high concentrations of Cd. Metal concentrations were highest in summer, a period in which oyster meat condition index was relatively low. Copper values were highest in 1986–1987, likely elevated by erosion from Cu-Ni alloy condensers at a local power plant. Silver and Cd values exhibited more year-to-year variation. A number of factors were examined as candidates to explain the interannual differences, including river flow, salinity, and oyster condition, but none was able to explain the high and low years. Samples collected in spring and late summer of 1996 at a number of oyster bars located along the length of the Patuxent River showed that concentrations of all three metals increased with distance up-river. For Cd, the upstream increase was linear with distance, while for Ag and Cu, there was a secondary maximum near river km 16. A close correlation was observed between Ag and Cu for individuals at each site, with a poorer correlation between Cd and either Ag or Cu.

Trace metal concentrations in the sediments and plants of the Danube Delta, Romania

Wetlands systems generally are considered as filters, retaining allochthonous metals that can have toxic effects on biota. We investigated patterns of spatial variability in trace metal concentrations in sediments and tissues ofPhragmites australis in the marshes of the Danube Delta, Romania in 1993 and 1994. Mean concentrations (±s.e) of Ni, Cr, and Pb in roots were 10.0±0.7, 2.7±0.2, and 11.3±0.5 μg g−1 dry wt, respectively, and in leaves were 0.3 ± 0.1, 0.1 ±0.0, 0.2 ± 0.0 μg g−1 dry wt, respectively. Mean concentrations (± s.e.) of Ni, Cr, Zn, and Cu extracted (0.5M HCl) from sediments were 16.4 ± 0.8, 3.0 ± 0.2, 45.4 ± 1.7, and 29.2 ± 2.3 μg g−1 dry wt, respectively. Sediment metal concentrations decreased significantly (p < 0.01) with distance from the Delta origin, but concentrations in roots and sediments did not vary with distance into the marsh from lake edges nor with distance from main river channels in the Delta. Concentrations of extractable metals from marsh sediments were not correlated to concentrations in roots, suggesting that factors other than labile concentrations in sediments control metal uptake and storage in roots.

Trace metals and antioxidant enzymes in gills and digestive gland of the Mediterranean mussel Mytilus galloprovincialis.

A seasonal variability of trace metal concentrations and antioxidant enzymes was observed in gills and digestive gland of the Mediterranean mussel Mytilus galloprovincialis from both a polluted and a nonpolluted population. Trace metals (As, Cu, Fe, Mn, Pb, and Zn) exhibited, in both organs, maximum values in later winter-early spring followed by a progressive decrease during the summer. While in the gills this behavior probably reflects a different bioavailability of metals, in the digestive gland it is influenced mainly by the progressive infiltration of the organ by gonadic tissues during gametogenesis. Metals, as other pollutants, are known to influence the oxidative status of these organisms and antioxidant enzymes have been often proposed as biomarkers of exposure to contaminants. In this respect, it was of interest to compare the variations of these biochemical parameters with those of metal levels in two mussel populations from a polluted and a nonpolluted site, respectively. The biochemical parameters examined included the level of glutathione and the activity of the following glutathione dependent and antioxidant enzymes: glyoxalase I, EC 4.4.1.5; glyoxalase II, EC3.1.2.6; glutathione S-transferases, EC 2.5.1.18; glutathione reductase, EC 1.6.4.2; Se-dependent, EC 1.11.1.9 and Se-independent, EC 2.5.1.18 glutathione peroxidases; catalase, EC 1. 11.1.6; superoxide dismutase, EC 1.15.1.1. Seasonal variations of trace metals did not appear to influence those of biochemical parameters, which generally showed an opposite trend with higher enzymatic activities in summer when trace metal concentrations were lower. The effects of metals on antioxidant enzymes were more evident when the two mussel populations were compared. In particular, organisms from the polluted site showed lower levels of glutathione and higher enzymatic activities of glyoxalase I even though the magnitude of these differences was not constant during the year. Moreover, native mussels from both the polluted and control populations exhibited limited differences in the activities of glutathione reductase, glutathione peroxidases, catalase, and superoxide dismutase, suggesting the possibility of some biochemical adaptation in organisms from chronically polluted environments.

Variations in Trace Metal Concentrations in American Oysters (Crassostrea virginica) Collected from Galveston Bay, Texas

Nearly one thousand oysters (Crassostrea virginica) were collected at 15 sites on four sampling trips to Galveston Bay during 1992–1993. Iron, silver, arsenic, cadmium, copper, lead, and zinc were determined in the whole soft part of the individual oysters. Trace metal concentrations were found to vary among individuals within a site on a given trip, and spatially and temporally around the Galveston Bay estuarine system. Differences in metal concentrations from site to site were a factor of 5 or more for some metals, and similar differences were found from time to time at a given site. Zinc was found in anomalously high concentrations at several sites, mainly along the west side of Galveston Bay. Isolated high values of other metals were found scattered throughout the bay; however, only one site (GBSL, near Swan Lake in lower Galveston Bay) was found to have significantly higher than average concentrations for several metals (Ag, Cu, Pb, and Zn). One obvious trend found in this study was that metal concentrations, except for As, were highest in the summer, followed by the fall, and lowest in the winter and spring. The temporal changes in metal concentrations in oysters cannot be explained by changes in body weight in different seasons, and are apparently caused by changes in environmental conditions (e.g., metal input, salinity) or biological activity (e.g., metabolism, depuration).

Trace metals in sediments at the lower reaches of Mediterranean coastal rivers, Israel

Concentrations of mercury, lead, copper, zinc, cadmium, iron and partially chromium, manganese, nickel and aluminium, were recorded in surface sediments at the lower reaches of 11 rivers from the Mediterranean coastal zone of Israel, during 1988-1993. Excluding the lower Kishon river, no major contamination was found at most of the stations when trace metal concentrations were normalized against iron concentrations (trace metal/iron ratios) and compared to levels recorded in stream sediments from the southern drainage basin of the Kishon river. Minor enrichments found in part of the rivers are attributed to land-based point sources of pollution. Variations in trace metal concentrations at the estuaries are related to high influx of fine-grained sediments transported by heavy floods during rainy winters, which later are resuspended and transported seaward by bottom currents.

Trace metals in sediments at the lower reaches of Mediterranean coastal rivers, Israel

Concentrations of mercury, lead, copper, zinc, cadmium, iron and partially chromium, manganese, nickel and aluminium, were recorded in surface sediments at the lower reaches of 11 rivers from the Mediterranean coastal zone of Israel, during 1988–1993. Excluding the lower Kishon river, no major contamination was found at most of the stations when trace metal concentrations were normalized against iron concentrations (trace metal/ iron ratios) and compared to levels recorded in stream sediments from the southern drainage basin of the Kishon river. Minor enrichments found in part of the rivers are attributed to land-based point sources of pollution. Variations in trace metal concentrations at the estuaries are related to high influx of fine-grained sediments transported by heavy floods during rainy winters, which later are resuspended and transported seaward by bottom currents.

Seasonal variation of trace metal concentrations in the digestive gland of the Mediterranean mussel Mytilus galloprovincialis: Comparison between a polluted and a non-polluted site

Seasonal changes in metal (Cu, Fe, Mn, Pb, and Zn) concentrations were observed in the digestive gland of the Mediterranean mussel, Mytilus galloprovincialis, from both a polluted and a non-polluted population. Digestive gland of mussels from the polluted site showed metal concentrations appreciably higher than in non-polluted organisms, especially for Pb (up to 160 micrograms/g d.w.), Mn (up to 300 micrograms/g d.w.), and Fe (up to 8,500 micrograms/g d.w.), whereas the two populations showed maximum mean values, respectively, of 34 and 20 micrograms/g d.w. for Cu and 170 and 120 micrograms/g d.w. for Zn. Over 1 year (1991), differences between maximum and minimum values were moderate only in the unpolluted organisms. During gametogenesis, while the metal concentrations (expressed as microgram/g dry weight) decreased in the digestive gland, the tissue burden (as microgram) in that organ remained nearly constant or increased slightly. The apparent decrease in metal concentrations was probably due to the penetration of gonadic tissues into the digestive gland during gametogenesis, which biologically diluted metal concentrations in mussels from both the polluted and unpolluted populations. The effect of mussel size on trace metal concentrations in the digestive gland was demonstrated during different stages of the reproductive cycle. Higher concentrations were found in smaller organisms; however, during the spawning period, due to the fact that this is not a synchronous process within a population, the organisms exhibit a high variability in digestive gland weight which can mask this relationship when digestive gland weight is used as a size-index and as a parameter of the trace metal digestive gland burden.

Variations of trace metal concentrations in seawater and pearl oyster Pinctada radiata from Bahrain (Arabian Gulf)

Concentrations of seven trace metals in oysters ( Pinctada radiata) and paired seawater samples from two stations in Bahrain (Arabian Gulf) were determined every 6–8 weeks during the period March 1991–March 1992. The measured annual means in oysters were higher for Pb (7.64 μg g −1) and Cd (2.48 μg g −1) at an offshore Station 2, while Ni was higher in oysters at a nearshore Station 1. For Cu and Mn no differences were observed between oysters of both stations, however, Fe and Zn were higher in oysters of Station 1. No significant difference was observed in concentrations of trace metals in seawater of the nearshore or offshore stations or between individual metals. Seasonal distribution of metals in oysters and water indicated a tendency to increase towards the hot summer months (June, July-September). Generally, metal concentrations were higher in oysters irrespective of the station and the levels of Pb and Cd exceeded the WHO limits.

Continental origin and industrial sources of trace metals in the Northwest Atlantic troposphere

Trace metals (Mn, Fe, Ni, Cu, Zn, Cd, Pb and stable lead isotopes) have been analyzed in precipitation and total aerosols collected in the northwest Atlantic troposphere in April and November 1989. According to stable lead isotope signatures we encountered two main air mass sources, Mediterranean easterlies (206Pb/207Pb=1.131) and US westerlies (206Pb/207Pb=1.195–1.205). The phasing out of leaded gasoline has been invoked to explain the decrease of the 206Pb/207Pb ratios from 1.22 to 1.20 for the past 10 years in North America. Based on trajectory analyses, intermediate 206Pb/207Pb ratios are explained by a mixing of pure US westerlies with Canadian air masses (206Pb/207Pb=1.190–1.195) or Mediterranean air masses (206Pb/207Pb=1.18–1.19). Isentropic trajectories are very useful in explaining the variability of trace metal concentrations, a result of the fluctuating transport range of anthropogenic aerosols to remote marine areas of the North Atlantic. Lead concentrations appear to be closely correlated to the air mass transport patterns as defined from the meteorological analyses. For instance oceanic air masses transported over remote marine areas for more than three days were characterized by lead concentrations 2 to 10 times lower (Pb=0.5 to 2 ng/scm) than coastal air masses (Pb=3 to 10 ng/scm). Anthropogenic trace metal concentrations are generally in good agreement with the air mass signatures which display Pb and Cu, Ni, Zn concentrations higher than 2 and 10 ng/scm respectively in aerosol samples for the US source. Trace metal elemental ratios and soil enrichment factors were used to define industrial sources. Aerosol originating from the US exhibits the distinct industrial signature of Cu/Ni production and coal-oil combustion, while steel metallurgy could account for more than 50% of the overall Mn input into the Northwest Atlantic ocean.

Trace metals in bivalves and sediments from Tolo Harbour, Hong Kong

Concentrations of iron, copper, zinc, cadmium, and lead were determined in samples of sediment, mussel ( Perna viridis), and rock oyster ( Saccostrea cucullata) from nine locations in Tolo Harbour, Hong Kong. The concentrations of metals in bivalves did not vary greatly from one location to another and showed no correlation with the concentrations in sediments. The metal concentrations in bivalves are similar to published results in the same area, and concentrations of cadmium and lead are within the local legislative limits for seafoods. Comparison of metal concentrations in bivalves in March and May 1986 shows that lower concentrations of iron, copper, and cadmium in P. viridis occurred in May, suggesting seasonal variation of trace metal concentrations in mussels. This reduction was not evident in S. cucullata.

PH-related variations in trace metal concentrations in Lake Orta (Italy)

The relationships between pH and trace metal concentrations in the water of Lake Orta are discussed on the basis of data collected monthly between January 1984 and March 1988 and of laboratory experiments, in which calcium carbonate was added to lake water at two different pH. The results obtained from both sets of data are in good agreement, indicating a decrease in metal concentration with increasing pH in the case of aluminium, copper, iron and chromium; zinc and nickel do not show significant variations with increasing pH, while in the case of manganese the indications are scanty and do not permit a conclusion. These results suggest that there would be a decided decrease in metal concentrations if the water underwent liming at pH > 6.0–6.5, with a substantial improvement in the water quality, given the toxic effect of some of the metals in the water of Lake Orta.

The evaluation of heavy metals (Chromium, nickel, and cobalt) in the aqueous sediment surrounding a coal burning generating plant

Abstract The aqueous sediments of several lakes around Houston's first coal‐fired electrical plant have been analyzed for trace quantities (1–100 ppm) of chromium, nickel, and cobalt by atomic absorption spectroscopy. Variations of trace metal concentrations with respect to depth suggest a recent contribution to the aqueous sediment only where there is an increase in the top three centimeters of sediment. This study reveals that such additions of these metals to the aqueous sediment appear to have been minimal. Additionally, it is shown that iron and manganese influence the distribution of trace metals within the aqueous sediment. It 1s believed, however; that the low levels detected are due, primarily, to the plant having been operational for only one to two years during the course of this work. Nevertheless, this effort establishes invaluable baseline data for determining any future anthropogenic conditions due to either this coal‐fired electrical plant or other industrialization of southwest Houston.

Short-term variations in trace metal concentrations in the baltic

Baltic surface water was sampled at a fixed position at intervals of a few hours. The trace metal concentrations were measured by graphite furnace AAS after extraction. The mean concentrations found were (ng l −1): Cd, 30 ± 2.7; Cu, 800 ± 48; Fe, 358 ± 165; Ni, 820 ± 49; Pb, 16 ± 4.5; Zn, 900 ± 160. The variability in the trace metal concentrations is of the same order of magnitude as the precision of the method. Thus, no spatial variations in trace metal concentrations were found.

Dissolved and particulate trace metals in coastal waters of the Gulf and Western Arabian Sea

Concentrations of chemical species of selected heavy metals (Cu, Zn, Cd, Hg and Pb) were determined in surface waters from a series of coastal sites in Bahrain, United Arab Emirates (UAE) and the Sultanate of Oman. Analyses were carried out on bulk sea water samples as well as on suspended particulates by anodic stripping voltammetry. Heavy metal concentrations were relatively low with the exception of some “hot spots” which occurred in the vicinity of industrial and port activities. Average copper levels along the coast of UAE were generally higher than those measured in sea water from either Bahrain of Oman. Waters from the more populated and industrialised northwest coast of Oman were found to contain approximately 3 to 4-fold higher Cd and Zn (pH 4–4.5) concentrations than those from the southern coast, an undeveloped region adjacent to the more open waters of the Arabian Sea. Possible reasons for the observed regional variations in trace metal concentrations in Oman are discussed in terms of natural and anthropogenic input sources. Average concentrations in the Gulf (inside the Strait of Hormuz) were 510 ng 1 −1 (Cu), 340 ng 1 −1 (Zn), 20 ng 1 −1 (Cd), 16 ng 1 −1 (Hg) and 76 ng 1 −1 (Pb); in the western Arabian Sea along the coast of Oman concentrations averaged 290 ng 1 −1 (Cu), 180 ng 1 −1 (Zn), 37 ng 1 −1 (Cd), 11 ng 1 −1 (Hg) and 80 ng 1 −1 (Pb). Ranges of concentrations for these metals in Gulf and western Arabian Sea waters approach those which have been reported for open surface waters of the Atlantic, Pacific, Indian Oceans and the Mediterranean Sea indicating that, in general, the coastal waters of this region are not impacted by metal pollution and that the existing natural levels can be used as a point of reference for future pollutant studies.

Anatomically related variations in trace-metal concentrations in hair: a comment.

Journal Article Anatomically related variations in trace-metal concentrations in hair: a comment. Get access R W Thatcher, R W Thatcher Search for other works by this author on: Oxford Academic Google Scholar M L Lester M L Lester Search for other works by this author on: Oxford Academic Google Scholar Clinical Chemistry, Volume 29, Issue 9, 1 September 1983, Pages 1691–1692, https://doi.org/10.1093/clinchem/29.9.1691a Published: 01 September 1983

Anatomically-related variations in trace-metal concentrations in hair.

Scalp-hair analysis is used as an indicator of trace-metal concentrations in the human body. The major shortcoming of this approach is the inability to differentiate between endogenous and exogenous trace metals. Our analyses show no correlation between the concentrations of calcium, magnesium, copper, iron, or zinc in scalp hair and pubic hair in 67 donor-matched hair samples. We interpret this as a strong indication that exogenous trace metals make a significant contribution to the results for trace metals in human hair.

Continuous Cultivation for Apparent Optimization of Defined Media for Cellulomonas sp. and Bacillus cereus

Steady-state continuous culture was used to optimize lean chemically defined media for a Cellulomonas sp. and Bacillus cereus strain T. Both organisms were extremely sensitive to variations in trace-metal concentrations. However, medium optimization by this technique proved rapid, and multifactor screening was easily conducted by using a minimum of instrumentation. The optimized media supported critical dilution rates of 0.571 and 0.467 h for Cellulomonas and Bacillus, respectively. These values approximated maximum growth rate values observed in batch culture.

Variation in trace metal concentrations along single hairs as measured by proton-induced x-ray emission photometry.

TRACE elements in human and animal hair have been studied using spectrophotometric, atomic absorption, emission spectrographic, neutron activation, and spark source mass spectrometric methods. We report here measurements of trace elements in human hair using the technique of proton induced X-ray production.

Whale meat as a solution of the high cost of living : Anon. ( Scientific American, vol. cxvii, No. 5, p. 92, August 4, 1917.)

Humans have hunted all for centuries, sometimes to the point of near extinction of selected species. Recovery of exploited populations is proceeding under the guidance of various international commissions and regulatory groups. There has been a major surge in the literature on trace metal composition of marine mammals during the past 30 years. Mammals include the whales, porpoises, seals, dolphins, walruses, sea otters, and their relatives. The majority of the cetaceans and pinnipeds are exclusively marine, some frequenting the coast, but others oceanic, seldom approaching land. Many undertake extensive migrations and are widely distributed. A significant portion of the variability in trace metal concentrations within and between species of marine mammals is attributed to geographic location, year of capture, season, gender, blubber thickness, age, and fatty acid content. Tables have been outlined that illustrate concentrations of various trace metals in field collections of mammals. Some of the associated functions and defects due to the presence or absence of these trace metals have also been subsequently highlighted.