scholarly journals Mining-contaminated estuaries of Cornwall – field research laboratories for trace metal ecotoxicology

2020 ◽  
Vol 100 (2) ◽  
pp. 195-210 ◽  
Author(s):  
Philip S. Rainbow
Keyword(s):  
Trace Metals ◽  
Trace Metal ◽  
Field Research ◽  
Large Degree ◽  
Biological Organization ◽  
Lead And Zinc ◽  
Almost All ◽  
Developed World ◽  
Toxic Trace Metals ◽  
High Sediment

AbstractA century or so after the cessation of almost all mining in Cornwall, certain estuaries still have extremely high sediment concentrations of toxic trace metals, particularly copper and arsenic, but also lead and zinc. These high trace metal loadings in the sediments are to a large degree bioavailable to the local infauna, especially sediment-ingesting invertebrates. Some sediment trace metal bioavailabilities are so high as to be of ecotoxicological concern, with deleterious effects on the local biota at levels of biological organization up to and including changed community structure. The estuaries of interest here are those of the Rivers Carnon (Restronguet Creek), Tamar (and Tavy), Gannel, West Looe and Hayle. These estuaries are especially attractive field sites for comparative trace metal ecophysiology and ecotoxicology research for they lack the confounding presence of other anthropogenic contaminants inevitably present in most estuaries in the developed world. The estuaries also offer a range of combinations of different trace metals and a comparative gradient of sediment bioavailabilities of these trace metals.

scholarly journals Trace Metals Contamination in Bread Ingredients and Bread from Bakeries in Nigeria

2020 ◽  
pp. 26-37
Author(s):  
V. O. E. Akpambang ◽  
A. P. Onifade
Keyword(s):  
Trace Metals ◽  
Trace Metal ◽  
Human Consumption ◽  
Flame Atomic Absorption ◽  
Flame Atomic Absorption Spectrophotometer ◽  
Regular Consumption ◽  
Metal Contents ◽  
Wheat Flours ◽  
Toxic Trace Metals ◽  
Range Of Values

Bread loaves and bread ingredients (wheat flours, salt, sugar, yeast and water) were randomly sampled from ten bakeries within Akure metropolis of south western Nigeria and analysed to determine their safety levels for human consumption with respect to trace metal contents. The trace metals (Cu, Zn, Mn, Cr, Cd and Pb) were analysed in the samples using flame atomic absorption spectrophotometer. Results obtained revealed that toxic trace metals such as Cr, Cd and Pb were not detected in any of the samples. However, the levels of essential trace metals such as Cu, Zn and Mn had range of values in mg/kg: (0.039 – 0.091), (0.837 – 3.310) and (0.035 – 3.148); (0.056 – 0.091), (0.034 – 2.755) and (0.054 – 1.054) in the wheat flours and bread samples analysed respectively. This study revealed that the bread ingredients and loaves of bread sampled contained essential trace metals at levels that could not threaten the health of consumers over prolonged regular consumption.

scholarly journals Recommendations for Ensuring Environmental Safety of Ecosystem Restoration After Fire

2020 ◽  
Keyword(s):  
Heavy Metals ◽  
Trace Metals ◽  
Trace Metal ◽  
Soil Properties ◽  
Raw Materials ◽  
Field Research ◽  
Environmental Safety ◽  
Hazardous Substances ◽  
Adsorption Analysis ◽  
Characteristic Features

Purpose. To find ways to improve the soil properties of forest ecosystems after the action of the pyrogen- ic factor: to propose technological measures to restore the quality and improve the soil properties of the ecosystem; to prove the effectiveness of using clay in soil cleaning as a sorbent. Methods. The introduction of clay as a potential sorbent for cleaning fertile soils from trace metals is proposed. The mineral composition of the clay was determined by X-ray phase analysis. Clay materials can be successfully used in adsorption cleaning technologies. The method of phytoremediation with the help of dandelion to concentrate trace metal was used also. The concentration of trace metal was determined by atomic adsorption analysis. Results. The task of the experimental study was to substantiate the possibility of using cheap natural clay raw materials without its prior activation to remove trace metals from the soil solution. In the case of post-pyrogenic relaxation of ecosystems under conditions of man-caused load, the soil in the restored area may be contaminated with VM and other hazardous substances. The clay of the Kharkiv region was chosen for the experiment. The experiment proved the effectiveness of the use of clay in soil purification as a sorbent, and phytoremediation of dandelion in relation to heavy metals. Thus, both technical and biological methods of VM sorption to prepare the soil for planting can be recommended for the restoration of the forest ecosystem after a fire. The proposed technological measures to restore the quality and soil properties of the ecosystem include the implementation of design and survey work, including field research; implementation of the state ecological research (monitoring); cleaning the affected area from damaged trees; reclamation of soil fertility of regenerative territories, provided by design of restoration, depending on characteristic features of damages of sites and the subsequent application of regenerative territories. Conclusions. At postpyrogenic relaxation of ecosystems, in the conditions of technogenic loading, the efficiency of using clay in soil cleaning as a sorbent and phytoremediation with dandelion in relation to heavy metals has been proved.

scholarly journals Controls on the Spatial Distribution of Trace Metal Concentrations along the Bedrock-Dominated South Fork New River, North Carolina

Geosciences ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 519
Author(s):  
Jerry R. Miller ◽  
Xaviera Watkins ◽  
Thomas O'Shea ◽  
Cynthia Atterholt
Keyword(s):  
North Carolina ◽  
Spatial Distribution ◽  
Trace Metals ◽  
Trace Metal ◽  
Coarse Grained ◽  
South Fork ◽  
Metal Concentrations ◽  
Bed Sediments ◽  
Fe And Mn ◽  
Toxic Trace Metals

In marked contrast to alluvial rivers, few studies have examined the physical and geochemical controls on the spatial distribution of toxic trace metals along bedrock channels. This study examined the factors controlling the geographical pattern of selected trace metal (Cu, Cr, and Zn) concentrations along the bedrock-dominated channel of the South Fork New River (SFNR). The SFNR is located in the Blue Ridge Physiographic Province of North Carolina, and is representative of many rivers in mountainous terrains that are often subjected to the influx of toxic trace metals from historic and contemporary mining operations. The topography of the SFNR’s channel bed is highly variable and can be subdivided into pool and shallow bedrock reaches. The latter contained localized cascades characterized by topographically higher bedrock ribs that are separated by topographic lows, both of which are oriented oblique to flow. Accumulations of bed sediments are predominantly associated with the traverse bedrock ribs that generate high hydraulic roughness. Except for a few localized zones of enrichment, sediment-associated trace metal concentrations tended to vary within a narrow range of background values over the 36 km study reach. Elevated trace metal concentrations were closely linked to zones of high Fe and Mn concentrations, and were associated with pools located within or immediately downstream of bedrock cascades. The elevated concentrations of the metals appear to be derived from the erosion of lithologic units within the cascades that contain sulfidic layers or zones of mafic mineral enrichment, and which are known to occur in the underlying bedrock. Once eroded, these minerals and/or rock fragments were deposited within low-velocity zones created by the transverse ribs or within downstream pools. The enrichment of trace metals downstream of the cascades may also be due to the formation of Fe and Mn oxyhydroxides as turbulent flows aerate river waters as they traverse the cascades. Chemically reactive fine-grained (<63 µm) sediments had a relatively limited influence on the downstream variations in metal concentrations, presumably because the channel bed sediments are composed primarily of sand-sized and larger particles. Although a principal component analysis (PCA) suggested that reach-scale variations in channel and valley morphology may have partly influenced downstream variations in trace metal concentrations, the geographical patterns were primarily controlled by local geological and geomorphic factors associated with the bedrock cascades. The design of future sampling programs along such coarse-grained, bedrock rivers should consider the significance of these local controls on trace metal storage to effectively characterize and interpret downstream patterns in metal concentrations.

Trace metals in sediments from the Yarra River

1982 ◽  
Vol 33 (5) ◽  
pp. 761 ◽  
Author(s):  
M Ellaway ◽  
BT Hart ◽  
R Beckett
Keyword(s):  
Trace Metals ◽  
Trace Metal ◽  
Metal Concentration ◽  
Estuarine Sediments ◽  
Trace Metal Concentration ◽  
Metal Concentrations ◽  
Lead And Zinc ◽  
Sediment Fraction ◽  
Copper Lead ◽  
Yarra River

The distribution and phase association of iron, manganese, cadmium, copper, lead and zinc in bottom sediments taken from the freshwater, estuarine and bay regions of the Yarra River were investigated. The fraction of the estuarine sediments smaller than 20 �m contained substantially higher concentrations of cadmium, copper, lead and zinc than did the corresponding sediment fraction from the upper river and bay regions. Sequential chemical extraction revealed that most of the variability in the trace metal concentration of these sediments was associated with changes in the reducible phase. A substantial increase in trace metal concentrations occurred in going from river to estuarine sediments. For example, the lead concentration increased approximately eightfold (43-375 �g g-1), the zinc fourfold (122-447 �g g-1) and the copper almost twofold (64-106 �g g-1). This was attributed to coagulation and sedimentation of trace-metal- enriched iron and manganese oxides in the estuarine region. The subsequent decrease in metal concentrations in the bay sediments was due to either physical dilution of the contaminated sedlment with material of lower metal concentration or remobilizatlon of the trace metals from sediments deposited in the bay.

Identifying Sources of Sulfate Aerosols Reaching Whiteface Mountain, NY

1985 ◽  
Vol 43 ◽  
pp. 98-101
Author(s):  
James S. Webber
Keyword(s):  
Trace Metals ◽  
Acid Deposition ◽  
Surface Waters ◽  
Dry Deposition ◽  
Coal Combustion ◽  
Public Awareness ◽  
Sulfate Aerosols ◽  
Wet And Dry Deposition ◽  
Whiteface Mountain ◽  
Toxic Trace Metals

INTRODUCTION“Acid rain” and “acid deposition” are terms no longer confined to the lexicon of atmospheric scientists and 1imnologists. Public awareness of and concern over this phenomenon, particularly as it affects acid-sensitive regions of North America, have increased dramatically in the last five years. Temperate ecosystems are suffering from decreased pH caused by acid deposition. Human health may be directly affected by respirable sulfates and by the increased solubility of toxic trace metals in acidified waters. Even man's monuments are deteriorating as airborne acids etch metal and stone features.Sulfates account for about two thirds of airborne acids with wet and dry deposition contributing equally to acids reaching surface waters or ground. The industrial Midwest is widely assumed to be the source of most sulfates reaching the acid-sensitive Northeast since S02 emitted as a byproduct of coal combustion in the Midwest dwarfs S02 emitted from all sources in the Northeast.

Motivating Growth in Low-tech Manufacturing Industries

2019 ◽  
Vol 2 (1) ◽  
Author(s):  
Naomi HERTZ
Keyword(s):  
Value Chain ◽  
Field Research ◽  
Sustainable Competitive Advantage ◽  
Manufacturing Plants ◽  
Footwear Industry ◽  
Technological Platform ◽  
Qualitative Methodologies ◽  
Developed World ◽  
Depth Interviews

Intensive manual labor enterprises in the developed world face challenges competing with products imported from countries where manufacturing costs are low. This reduces the volume of domestic production and leads to rapid loss of knowledge and experience in production processes. This study focuses on the Israeli footwear industry as a case study. Qualitative methodologies were applied, including in-depth interviews and field observations. A literature review on previous research, and contemporary trends was conducted. The field research examines challenges along the value chain in small factories. It finds that mass production paradigms impose a decentralized process between designers and manufacturers and therefore do not leverage local potential into a sustainable competitive advantage for small factories. The proposed solution is a digital and technological platform for small manufacturing plants. The platform mediates and designs the connections between production, technology, and design and enables the creation of a joint R&D system.

IMPACTS OF HISTORIC LEAD AND ZINC MINING ON SEDIMENT AND AQUEOUS TRACE METAL CONCENTRATIONS IN THE BIG RIVER WATERSHED, MISSOURI, USA

2020 ◽  
Author(s):  
Christopher Mills ◽  
◽  
David C. Smith ◽  
Craig A. Stricker ◽  
John G. Schumacher ◽  
...  
Keyword(s):  
Trace Metal ◽  
Metal Concentrations ◽  
River Watershed ◽  
Lead And Zinc

scholarly journals Marine ammonia-oxidising archaea and bacteria occupy distinct iron and copper niches

2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Roxana T. Shafiee ◽  
Poppy J. Diver ◽  
Joseph T. Snow ◽  
Qiong Zhang ◽  
Rosalind E. M. Rickaby
Keyword(s):  
Comparative Genomics ◽  
Trace Metals ◽  
Trace Metal ◽  
Ammonia Oxidation ◽  
Testable Hypothesis ◽  
Niche Separation ◽  
Toxicity Threshold ◽  
Geologic Time ◽  
Additional Explanation ◽  
Ammonia Oxidising Archaea

AbstractAmmonia oxidation by archaea and bacteria (AOA and AOB), is the first step of nitrification in the oceans. As AOA have an ammonium affinity 200-fold higher than AOB isolates, the chemical niche allowing AOB to persist in the oligotrophic ocean remains unclear. Here we show that marine isolates, Nitrosopumilus maritimus strain SCM1 (AOA) and Nitrosococcus oceani strain C-107 (AOB) have contrasting physiologies in response to the trace metals iron (Fe) and copper (Cu), holding potential implications for their niche separation in the oceans. A greater affinity for unchelated Fe may allow AOB to inhabit shallower, euphotic waters where ammonium supply is high, but competition for Fe is rife. In contrast to AOB, AOA isolates have a greater affinity and toxicity threshold for unchelated Cu providing additional explanation to the greater success of AOA in the marine environment where Cu availability can be highly variable. Using comparative genomics, we predict that the proteomic and metal transport basis giving rise to contrasting physiologies in isolates is widespread across phylogenetically diverse marine AOA and AOB that are not yet available in pure culture. Our results develop the testable hypothesis that ammonia oxidation may be limited by Cu in large tracts of the open ocean and suggest a relatively earlier emergence of AOB than AOA when considered in the context of evolving trace metal availabilities over geologic time.

scholarly journals Significance of building and plumbing specifics on trace metal concentrations in drinking water

1991 ◽  
Vol 18 (6) ◽  
pp. 893-903 ◽  
Author(s):  
Inderjit Singh ◽  
Donald S. Mavinic
Keyword(s):  
Drinking Water ◽  
Trace Metals ◽  
Trace Metal ◽  
Water Samples ◽  
First Flush ◽  
Single Family ◽  
Metal Concentrations ◽  
Building Height ◽  
High Rise ◽  
Family House

Samples were taken from 72 high-rise apartment suites (6 suites in 12 individual high-rise towers) and 60 single-family houses located within the Greater Vancouver Regional District. The influence of the following factors on trace metal concentrations in 1-L first-flush drinking water samples and “running” hot water samples was investigated: building height, location, plumbing age, type of plumbing, and type of building. Results of this survey show that with the exception of building height, all factors had a correlation with one or more of the trace metals investigated. The trace metals examined were lead, copper, iron, and zinc. Lead was influenced primarily by building type, copper by plumbing age and type of plumbing, and iron by location. Elevated lead levels were associated with high-rise samples. New copper plumbing systems resulted in high copper levels. Highest iron levels in the drinking water were measured in the East Vancouver location. Zinc did not show a distinct correlation with any of the factors investigated. Brass faucets were the primary source of zinc in tap water. They also contributed substantially to the lead detected in the 1-L first-flush sample. Metal concentrations measured in the high-rise and house samples were compared with the U.S. Environmental Protection Agency's (USEPA) maximum contaminant levels (MCLs) and the proposed “no-action” level for lead. In high-rise samples, the 0.01 mg/L “no-action” level proposed for lead was exceeded in 43% of the samples, and 62% of the samples exceeded the current 1.0 mg/L MCL standard for copper. In single-family house samples, these values were 47% and 73%, respectively. The average lead concentrations were 0.020 mg/L for all high-rise samples and 0.013 mg/L for house samples. Regulatory levels stated above would still be exceeded in 6% of the cases for lead and 9% of the cases for copper, even after prolonged flushing of the tap in a high-rise building. In all cases associated with single-family houses, flushing the cold water tap for 5 minutes was successful in achieving compliance levels. Key words: aggressive water, compliance, corrosive, drinking water, first-flush, GVRD, high-rise, single-family house, trace metals, USEPA.

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