Differences In Metal Concentrations Research Articles

Ultrastructural Organization and Metal Elemental Composition of the Mandibles in Two Ladybird Species.

The mandibles are among the most important appendages of insects' mouthparts. Their morpho-functional organization is correlated with the variation in dietary preferences. In this study, we investigated the ultrastructural organization and metal composition of the mandibles of two ladybird species with different dietary habits: Harmonia axyridis (an entomophagous species) and Subcoccinella vigintiquatuorpunctata (a phytophagous species). The ultrastructural organization was studied using Scanning and Transmission Electron Microscopy, whereas the metal composition was investigated using Energy-Dispersive X-ray spectroscopy (EDX). Significant differences were observed in the general organization and metal enrichment pattern between the two species. The mandibles of H. axyridis are large and present a molar part with two teeth, with the apical one showing a bifid apex. In contrast, S. vigintiquatuorpunctata exhibited a molar region with several teeth on its apical part. The study revealed significant differences in metal content between the teeth and the prostheca of H. axyridis. Mn was the most abundant element in teeth, whereas Cl was more abundant in the prostheca. In the case of S. vigintiquatuorpunctata, Si was the most abundant element in the prostheca, while Mn was more present in the teeth. A comparison between the two species revealed that both teeth and prostheca showed significant variation in the elemental composition. These findings underscore the role of dietary preferences in shaping the structural and metal composition variations in the mandibles of these two ladybird species.

Concentration and mobility of trace elements (Li, Ba, Sr, Ag, Hg, B) and macronutrients (Ca, Mg, K) in soil-orchid system on different bedrock types.

The mobility of chemical elements in the soil-orchid system has been poorly studied. The aim of this study is to evaluate the uptake and mobility of several trace (Li, Ba, Sr, Ag, Hg, and B) and macronutrients (Ca, Mg, and K) in the orchid Anacamptis morio (L.) R.M.Bateman, Pridgeon & M.W.Chase from soils in western Serbia. The sampling sites are characterized by three different bedrock types-cherts, limestones, and serpentines, which are the source of the significant chemical differences in the elemental status of the soil and plant tissues. The four-step Community Bureau of Reference sequential extraction procedure was used to determine the distribution of fractions and predict their potential phytoavailability. The orchid and soil samples were analyzed for total elemental content analysis using ICP-OES. The greatest potential for plant availability was determined for Ba and Sr, representing about 80% of the total soil content. More than 40% of Li in the soils was found to be potentially phytoavailable. Significant correlations were found between the total content of Li, B, and Sr in soils. Between 38 and 60% of Li content and more than 80% of Ba and Sr content were determined to be potentially phytoavailable by sequential analysis. The highest bioconcentration factor (> 1) was determined in the case of B and Sr for all orchid organs, while translocation factor for Li was highest in tubers and leaves. The studied elements were mainly stored in tubers and roots, indicating the exclusion strategy of A. morio as a metal tolerance mechanism. The data obtained showed significant differences in metal content in soils and plants originating from sites with different parent materials, suggesting that bedrock type and associated soil properties are important factors that determine chemical element mobility and uptake.

HEALTH RISK ASSESSMENT OF METAL CONTENT IN TUMERIC (Curcuma longa) CULTIVATED IN MARO FARMLANDS KAJURU LGA, KADUNA STATE, NIGERIA

Turmeric powder (Curcuma longa) is a yellow powder obtained by grinding dried matured rhizomes. Curcuma longa is utilized in culinary and cosmetic preparations, as well as medicinal formulations. It's available in Kajuru LGA, Kaduna state, Nigeria's Maro ward. The purpose of this study was to carry out a health risk assessment of Na, Mg, K, Ca, and Fe metals in turmeric cultivated within Maro, Chibiya, Karamai, and Angwan Gamu farm lands. Using the Perkin Elmer pin AAcle 900H, four Curcuma longa samples were obtained from diverse fields and subjected to AAS analysis following wet digestion to assess metal contents. The data was examined statistically using analysis of variance (ANOVA). Ca>Mg>Na>K>Fe were found to be the most abundant metals in Curcuma longa. The maximum level advised by the World Health Organization for all elements was not exceeded (WHO). At P>0.05, there were substantial differences in metal content in Tumeric across all farmlands. Consumers of Curcuma longa cultivated in Maro will not be exposed to any potential health problems because the Target Hazard Quotient (THQ) value of all metals was less than one and the Hazard Index (HI) value for Fe metal was less than one. It was suggested that more research be done on the health risks of other metal content in Curcuma longa rhizome.

Sardine and anchovy as bioindicators of metal content in Greek coastal waters

Metal and element concentrations (Li, Na, Mg, P, Ca, V, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Rb, Sr, Mo, Pd, Cd, Cs, Ba, Hg, Tl, Pb, U) were monitored in the tissues of sardine (Sardina pilchardus) and anchovy (Engraulis encrasicolus) from six Greek coastal areas subjected to different natural and anthropogenic forcings in order to be assessed as bioindicator species of marine metal pollution. Sardine and anchovy provided a thorough view of the metal pollution load of each site in accordance with local pollution sources. The wide range of pressures applied in Elefsina Gulf and Thermaikos Gulf are depicted in the large number and the kind of elements reaching maximum concentrations among the sites (e.g. Pb, Cu, Hg, As in Elefsina Gulf, and Cd, Ni, P in Thermaikos Gulf) while in the rest of the sites (Amvrakikos Gulf, Strymonian Sea, Thracian Sea, Artemisium Straits), few elements were found at maximum levels. Statistically significant site-specific differences in metal content were detected. The differentiation in metal content of the fish tissues among the sites could be attributed to anthropogenic pressures, different background levels and environmental conditions. Sardine and anchovy can be evaluated as appropriate, reliable and useful bioindicator species of marine metal pollution.

Application of Calcified Structures in Fish as Indicators of Metal Exposure in Freshwater Ecosystems

Although there are common and well-established bioindicator organisms and tissues, there is still a need for reliable and sensitive bioindicators in aquatic environments. In the present pilot study, calcified structures in fish were applied as indicators of metal exposure in combination with commonly used fish soft tissues and intestinal parasites, therefore comprising short- and long-term indicators. Patterns of metal accumulation and distribution in soft (muscle, liver) and hard (scales, otoliths) tissues of brown trout (Salmo trutta Linnaeus, 1758) and their intestinal parasites, acanthocephalans (Dentitruncus truttae Sinzar, 1955), from the Krka River influenced by industrial and municipal wastewaters were estimated and compared. Most elements had higher levels in acanthocephalans, scales and liver than muscle and otoliths, possibly reflecting differences in metal uptake routes, tissue function and metabolic activity. Despite the recorded differences in metal contents, all applied bioindicators reflected environmental conditions in a similar way, indicating higher levels of most elements in fish from the contaminated rather than from the reference site. Acanthocephalans were confirmed as sensitive bioindicators due to effective metal accumulation capacity, while the combination of soft and hard tissues provided extended temporal information on metal exposure. Wastewater impact was evidenced as moderate metal pollution by all applied indicators and pointed to present but also long-term disturbances in the Krka River and the importance of continuous monitoring and protective actions.

Seasonal variation of trace elements and stable isotope (δ13C and δ15N) values of commercial marine fish from the black sea and human health risk assessment

The purpose of this study is to examine changes in stable carbon and nitrogen isotope ratios, to determine the levels of metals (aluminum, copper, iron, manganese, lead, and zinc), and to assess the health risks associated with consumption of the most consumed pelagic and demersal fish species in Turkey. Trachurus mediterraneus, Mullus barbatus, and Merlangius merlangus were seasonally caught from the Eastern Black Sea in 2020. Concentrations of heavy metals in fish muscle tissues were measured using Inductively Coupled Plasma-Optical Emission Spectroscopy whereas stable isotope analysis was performed using Isotope Ratio Mass Spectrometer. The detected levels of metals studied in all fish species except lead were below the determined limits of national and international standards. In addition, the carcinogenic risk index was considered significant in all fish species. Considering the principal components analysis results, Cu and Pb may have originated from similar sources. No significant difference in metal content and stable isotope rates was observed between different species of fish. Also, target hazard quotient values were found below 1 in all species, which means that the consumption of the studied fish species does not pose a health risk.

Trace elements in pelagic Sargassum species in the Mexican Caribbean: Identification of key variables affecting arsenic accumulation in S. fluitans

Since 2014, the Mexican Caribbean beaches have received massive influxes of the brown seaweed Sargassum (S. fluitans III, S. natans I and S. natans VIII), causing serious ecological and economic effects. Concentrations of arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), lead (Pb), and zinc (Zn) were determined over an annual cycle in pelagic Sargassum species from massive influxes into the Mexican Caribbean. The contribution of trace elements, polysaccharides (alginate and fucoidans), and their main functional groups (uronic acids and sulfate) to arsenic content in Sargassum fluitans — the most abundant species in the Sargassum influx — is discussed. Arsenic was recorded in all samples, yielding mean concentrations of 74.2 ± 2.84 mg kg−1. Significant differences were found between species for As, Cu, Fe, and Pb, but not for Cd and Zn; also, S. fluitans showed significant differences in metal content between seasons for all elements, as well as in alginate and uronic acids from fucoidan. The season of the year, copper, iron, uronic acids, and sulfate content in fucoidan were the main variables associated with arsenic accumulation in S. fluitans as evidenced with a Generalized Linear Model. Arsenic content in Sargassum biomass exceeded the maximum allowable level in the rainy season; therefore, the content of this trace element should be carefully monitored for safe usage of Sargassum biomass.

Controls on metal enrichment in ferromanganese crusts: Temporal changes in oceanic metal flux or phosphatisation?

Oceanic hydrogenetic ferromanganese (Fe-Mn) crusts are a major repository for many metals, such as Co, Ni, Cu, Pt, Te and REE, which are essential for decarbonisation of transport and energy systems. Secondary mineralisation processes, occurring during phosphatisation episodes, commonly impregnate the shallower deposits with carbonate fluorapatite (CFA). The suboxic oceanic conditions during such events are frequently invoked to explain the lower Co content and unusually high Ni, Cu, Zn and Pt content of older phosphatised crusts. Here, the hypothesis of suboxic diagenetic recrystallization induced by phosphatisation episodes as a driving mechanism for Ni, Cu, Zn and Pt enrichment and Co depletion is evaluated. Accurately dated geochemical profiles, spanning 75 Ma of depositional history, for a shallow (1100 mbsl) phosphatised sample and a deeper (3100 mbsl) unphosphatised sample from Tropic Seamount in the north-east Atlantic, are compared. An isocon analysis, which allows to quantitively evaluate chemical gains and losses in mass transfer and therefore permits compensation for the dilution effect induced by the addition of CFA in the Fe-Mn crusts, demonstrates that no loss of Co has occurred in the phosphatised crust, whilst Pt, Te, Cu, Ni and Zn are enriched relative to younger, unphosphatised Fe-Mn crust. Both geochemical profiles show sympathetic trends and similar amplitudes of variation in concentration. This excludes phosphatisation as the driving mechanism for the metal enrichment and depletion. Systematic differences in metal content between the two samples, such as higher Cu and lower Co content in the deeper sample, are consistent with the depth profile of dissolved metal concentrations in the water column. The variability observed in the geochemical profiles is consistent with temporal changes in metal fluxes to the ocean, as a result of the evolving climate and oceanographic configuration of the north-east Atlantic Ocean through the Cenozoic. It is concluded that changing metal fluxes, rather than secondary mineralisation process associated with phosphatisation, is the dominant control on the primary metal content in Fe-Mn crust deposits at Tropic Seamount.

Toxicity of particles emitted by fireworks

BackgroundParticle matter (PM) has been associated with increased morbidity and mortality rates across the world. This study was designed to test the hypotheses that pyrotechnic firework displays introduce significant amounts of toxic metals into the atmosphere and are hazardous to human health. Size-selective emissions from 10 different fireworks displays were collected during particle generation in a dynamic, stainless steel chamber and tested for toxicity in cells. A subset of 2 particle types were tested in vivo in mice. At doses that did not produce cytotoxicity in an LDH assay, in vitro reactive oxygen species (ROS) formation was measured in bronchial epithelial airway (BEAS-2B) and human pulmonary microvascular endothelial (HPMEC-ST1.6R) cell lines treated with size-fractionated particles from the emissions of fireworks.ResultsSignificant increases in ROS, in both cell types, were dependent upon the type of firework but not particle size. The in vitro ROS activity was correlated with lung inflammation produced in groups of mice treated by oropharyngeal aspiration with 0, 50, or 100 μg fireworks PM10/mouse. Trace metal analyses of the PM10 samples showed significant differences in metal content among fireworks type. Interestingly, the PM10 sample for the fireworks type producing the greatest in vitro ROS response in BEAS-2B cells contained ~ 40,000 and ~ 12,000 ppm of lead and copper, respectively. This sample also produced the greatest inflammatory response (i.e., increased neutrophils in bronchoalveolar lavage fluid) in mice.ConclusionsThese findings demonstrate that pyrotechnic display particles can produce adverse effects in mammalian cells and lungs, thus suggesting that further research is needed to expand our understanding of the contribution of metal content to the adverse health effects of fireworks particles. This information will lead to the manufacture of safer fireworks.

Accumulation of Nickel by Excluder Thlaspi arvense and Hyperaccumulator Noccaea caerulescens upon Short-Term and Long-Term Exposure

Abstract: The ability to accumulate nickel (Ni) was compared in hyperaccumulator Noccaea сaerulescens F.K. Mey and excluder Thlaspi arvense L. after a short-term (1, 2, or 3 days) and long-term (8 weeks) exposure. T. arvense and four accessions of N. сaerulescens (La Calamine (LC), Saint Felix de Pallieres (SF), Monte Prinzera (MP), and Lellingen (LE)) were grown on a half-strength Hoagland`s solution in the presence of 25 µM Ni(NO3)2 (N. сaerulescens and T. arvense) and 250 µM Ni(NO3)2 (N. сaerulescens; T. arvense for only 1–3 days). Metal content in the roots and shoots was determined by atomic absorption spectroscopy. The Ni content per unit mass in the roots and shoots of N. сaerulescens in most cases did not differ significantly after the short-term incubation. At 25 µM Ni in the nutrient solution, its content in the roots of LC plants after 2–3 days of incubation was lower than in T. arvense, whereas Ni content in the shoots of these plants was similar. In the plants of other accessions of N. сaerulescens, Ni content in the roots and shoots in most cases was higher than in T. arvense. At 250 µM Ni, the differences in metal content in the roots were insignificant, and its content in the shoots in all the accessions of the hyperaccumulator was much higher than in the excluder. The Ni translocation factor was higher in N. сaerulescens than in T. arvense and exceeded unity only in the plants of MP accession. After the long-term exposure, the Ni translocation factor was higher than 1 in plants of all accessions of N. сaerulescens and decreased in the following order: MP ≈ LC > LE ≥ SF; in T. arvense, it did not exceed 0.3. Upon both long-term and short-term exposure, the ability to accumulate Ni by N. сaerulescens plants of different accessions generally increased in the following order: LC < SF < LE < MP. However, minor changes were observed depending on the duration of exposure and Ni concentration in the medium. Thus, considerable differences in the ability to accumulate Ni among the plants of different accessions of hyperaccumulator N. сaerulescens became apparent as early as during the first days of exposure to Ni and hardly depended on the duration of incubation or metal concentration in the medium. The obtained data confirm the assumption about a constitutive or genetically predetermined ability of plants of different N. сaerulescens accessions to accumulate Ni.

Metal Content of Nutritional and Toxic Value in Different Types of Brazilian Propolis.

Brazilian raw propolis samples (brown, green, red, and yellow) were investigated to evaluate the content of three elements of nutritional value (Cu, K, and Se) and three toxic metals (As, Cd, and Pb). The propolis samples (n = 19) were obtained from different regions of Brazil and analysed by atomic absorption spectrometry after microwave-assisted digestion. A descriptive analysis of the variables was carried out, and nonparametric tests (Kruskal–Wallis or Mann–Whitney) were performed to verify the differences in metal contents. The elemental concentrations of the Brazilian propolis were in the following ranges: As < 0.048–8.47 μg·g−1, Pb < 0.006–0.72 μg·g−1, Cu 0.57–11.60 μg·g−1, Se < 0.041–0.54 μg·g−1, and K 0.23–7.94 mg·g−1; Cd was below LOD (0.008 μg·g−1) in all samples, except one. Seven samples exceeded the limits defined for As or Pb by the Brazilian regulation.

Differences in metal content in liver of Heteromyids from deposits with and without previous mining operations

Some rodents of the family Heteromyidae can survive without drinking water, as they obtain it from food. All these species have in common that they eat seeds and fruits. The content of trace metals in food varies depending on the local geology and anthropogenic activities. Baja California Sur has mineral deposits that have been exploited; thus, the metals released may be incorporated into seeds and fruits that are consumed by Heteromyidae. Therefore, metal content in the liver is expected to reflect the presence of mining in soil where these rodents thrive. Individuals from different species of Heteromyidae were collected at sites with mineral deposits; these were divided into two groups: rodents captured in sites with a history of mining operations (Santa Rosalia, San Juan de la Costa, and El Triunfo), and rodents captured in areas with no mining activities (El Vizcaino, Punta Abreojos, Magdalena Island, and Santiago). The liver of these rodents was excised and its manganese, copper, cadmium, lead, zinc, nickel, and iron contents were determined using atomic absorption spectrophotometry. Manganese was the element that showed the highest significant differences between species, followed by zinc and copper. Iron and cadmium showed the lowest differences. Nickel and lead showed no differences. Chaetodipus arenarius showed significant differences between sites in copper and lead content; C. spinatus did not show significant differences for manganese, copper, nickel, and iron, but it did for cadmium and lead content. Differential accumulation of metals occurs across species. These results indicate that the same species could be used for comparative purposes in pollution monitoring. The comparison of different heteromid species, despite their sharing similar feeding habits and belonging to the same family, can lead to misinterpretation due to the variability of the results. This is probably due to the requirements and tolerances regarding essential elements, such as manganese and zinc, to or tolerance to non-essential elements such as cadmium and lead, which may vary across species.

Settled Dust from Urban and Suburban Roads in an Industrial City Area: Location and Seasonal Differences in Metal Content.

Settled road dust, present on all roads surfaces in a relatively high abundance, is a complex of particles-ranging from nanosized to microsized-from both natural and anthropogenic sources and may pose possible risk to the biosphere as well as influence the atmosphere because of the road dust resuspension. Geographical and seasonal differences in heavy metal content of the settled road dust were studied at two sites: urban site with a heavy traffic in the industrial city of Ostrava, Czech Republic and suburban site of Ostrava with a negligible traffic load in settlement Ludgeřovice. Dust samples were collected monthly during the period from March to October 2015. Obtained dust samples were homogenized and subsequently analyzed by Inductively Coupled Plasma Atomic Emission Spectroscopy; the results were then assessed by multivariate statistical methods (Principal components analysis, Factorial analysis on mixed data). The difference in the content of Ba, Cr, Cu, Mn, Ni, Pb, Sb, Sn, V, and Zn was explainable mainly by the factor of the site only the content of Fe was significantly dependent on the month of sampling. The contents of the particular elements and the correlations found among them confirm the assumption that heavy metals detected in the road dust samples from the urban site most likely originated primarily from the traffic-and particularly from the non-combustion processes.

Analysis of Design Efficiency of Tube Bundles of Shell-and-Tube Heat Exchangers with a Rigid Structure

The metal content of tube bundles of rigid-type shell-and-tube heat exchangers is analyzed in terms of their design options and used materials. Outer tube diameters, tube material, wall thickness, pressure in the tubes, and inner diameter of the exchanger are considered as the influencing factors. Use of tube bundles consisting of strong tubes is proposed for reducing metal content of tube bundles. High-strength low-alloy steel tubes are recommended for medium and high pressures in the tubes. In the case of low pressure in the tubes, the difference in metal content of carbon steel and high-strength low-alloy steel tube bundles is negligible.

Metals and elements in sardine and anchovy: Species specific differences and correlations with proximate composition and size

Species – specific differences in the levels of 26 metals and elements in sardine and anchovy are investigated and the factors of proximate composition (proteins, lipids, ash) and body size (length, weight) that may affect the metal and elemental concentrations in fish are explored. Statistical analysis revealed that levels of metals and elements in fish seem to strongly depend on species. Significantly higher levels of most of the metals and elements studied have been observed in anchovy compared to sardine at each of six different sites. The observed species-specific differences in metal content could be attributed to different proximate composition and size among other factors. The significant (positive or negative) correlations found between lipids, proteins, ash, weight, length and metals or elements, suggest that higher levels of most of the metals and elements studied can be associated with lower lipid content, greater protein and ash content and smaller size.

Trace metal distribution in pelagic fish species from the north-west African coast (Morocco)

In the current study, ten elements contents (Fe, Zn, Mn, Cu, Cr, Co, Ni, Cd, Pb and Hg) have been measured in muscle and liver of four pelagic fish species (Engraulis encrasicolus, Sardina pilchardus, Scomber japonicus and Trachurus trachurus) from the north-west African coast (South Atlantic Moroccan coast), collected during summer and autumn seasons (July and December 2013, respectively). Significant differences in metal contents were found between the different species (p < 0.05). Metals levels were also much higher in liver than those recorded in muscle tissues. The concentrations of Fe, Zn, Cd, Co, Cu and Pb were significantly higher in mackerel liver (p < 0.05).While, in muscle, anchovy presents a higher content of Mn, Cu, Cr, Ni and Pb. A high level of cadmium was recorded in liver of the different species which can be attributed to an anthropogenic source (phosphate industry) and to natural sources (upwelling activities). The main concentration of toxic elements (Cd, Pb and Hg) recorded in the four edible muscles of pelagic fish species, under study, were below the established values by the European Commission Regulations and show that their effect on the consumers health can be considered as negligible.

Sulfur isotope and fluid inclusion geochemistry of metamorphic Cu–Au vein deposits, central Cobar area, NSW, Australia

ABSTRACTVein-type, structurally controlled Cu–Au mineralisation hosted by turbidites of late Silurian to earliest Devonian age, forms an important resource close to the eastern margin of the Cobar Basin. Here we report 103 new sulfur isotope analyses, together with homogenisation temperatures and salinity data for 545 primary two-phase fluid inclusions for the mineralised zones from the central area of the Cobar mining district. A range in δ34S values from 3.8 to 11.2‰ (average 7.9‰) is present. Sulfur is likely to have been derived from rock sulfur/sulfide in basin and basement rocks, but there may be an additional connate-derived component. Homogenisation temperatures (Th) for inclusion fluids trapped in quartz and minor calcite veins range from near 150°C to 397°C. Fluid inclusions are characterised by a low CO2 content and low, but variable salinities (2.1–9.1 wt% NaCl equivalent). Generations of inclusion fluids correspond to six paragenetic stages of vein quartz deposition and recrystallisation at the Chesney mine. Primary fluid inclusions in the first two stages were subjected to re-equilibration resulting from increased confining pressure. Their Th range (151–317°C) is considered a minimum for the temperature of these fluids. Sulfide and gold deposition at Chesney appears to be related to fluids of moderately high Th (range 270–397°C) associated with the final paragenetic stage. Th for the ore-related fluids may be close to the solvus of the H2O–NaCl–CO2 system and hence near trapping temperatures. Late-stage entry of a hot, moderately saline ore-forming fluid is implicated as the origin of the Cu–Au mineralisation. However, comparison with geochemical data for the vein-style Zn–Pb–Ag deposits at Cobar demonstrates that differences in metal content for individual zones cannot be attributed to major differences in fluid temperature or salinity. Rather, these differences are probably due to variations in source-rock reservoirs and structural pathways along which the ore-forming fluids moved.

Bioaccumulation of metals in ryegrass (Lolium perenne L.) following the application of lime stabilised, thermally dried and anaerobically digested sewage sludge

The uptake and accumulation of metals in plants is a potential pathway for the transfer of environmental contaminants in the food chain, and poses potential health and environmental risks. In light of increased population growth and urbanisation, the safe disposal of sewage sludge, which can contain significant levels of toxic contaminants, remains an environmental challenge globally. The aims of this experiment were to apply municipal sludge, having undergone treatment by thermal drying, anaerobic digestion, and lime stabilisation, to permanent grassland in order to assess the bioaccumulation of metals (B, Al, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Nb, Mo, Sb, Ba, W, Pb, Fe, Cd) by perennial ryegrass over a period of up to 18 weeks after application. The legislation currently prohibits use of grassland for fodder or grazing for at least three weeks after application of treated sewage sludge (biosolids). Five treatments were used: thermally dried (TD), anaerobically digested (AD) and lime stabilised (LS) sludge all from one wastewater treatment plant (WWTP), AD sludge from another WWTP, and a study control (grassland only, without application of biosolids). In general, there was no significant difference in metal content of the ryegrass between micro-plots that received treated municipal sludge and the control over the study duration. The metal content of the ryegrass was below the levels at which phytotoxicity occurs and below the maximum levels specified for animal feeds.

Metal concentrations in hair of patients with various head and neck cancers as a diagnostic aid.

Head and neck cancers are one of the most frequent cancers worldwide. This paper attempts to evaluate disturbances of homeostasis of the necessary elements (calcium, magnesium, zinc, copper, iron, manganese) and changes in the levels of toxic metals (lead, cadmium, cobalt, chromium VI) in hair of patients with head and neck cancers, as well as people without a diagnosed neoplastic disease. In order to quantify the necessary elements and toxic metals, a method using ICP-MS and ICP-OES techniques had been developed and validated. The studies have shown that patients with head and neck cancer used to drink alcohol and smoked much more frequently than healthy individuals, both in the past and presently. Statistically significant differences in concentrations of average metal content in the group of patients with head and neck cancers compared to the control group were confirmed. Significant differences in metal content between the group of patients with head and neck cancers and healthy individuals were found which enabled distinguishing between the study groups. To this end, a more advanced statistical tool, i.e. chemometrics, was used. The conducted research analyses and the use of advanced statistical techniques confirm the benefits of using alternative material to distinguish the patients with head and neck cancers from the healthy individuals.

Heavy Metal Content in PM2.5 Air Samples Collected in the Metropolitan Area of Monterrey, México

ABSTRACTThe air PM2.5 concentration and its heavy metal content (Fe, Pb, Mn, Ni, As) were measured in the Metropolitan Area of Monterrey, Méxicoin Mexico, an area that is characterized by both very active and diverse industrial activity and intense highway traffic and industrial activity. The 24-h PM2.5 samples were collected in two different zones during a 1-year-long measurement program (February 2008–February 2009). The year PM2.5 average was above 15 μg/m3 exceeding Mexican and international standards. The difference of PM2.5 in each zone was not statistically significant. The greatest metal content was for iron, followed by lead, manganese, nickel and arsenic. The difference in metal content for Pb, Mn, and As was statistically significant.