Total Manganese Content Research Articles

Assessing Phytoremediation Potentials of Selected Plant Species in Restoration of Environments Contaminated by Heavy Metals in Gold Mining Areas of Tanzania

Phytoremediation uses green plants for in-situ removal, degradation, and containment of contaminants in soils, surface waters and groundwaters. However, little research has been conducted on the phytoremediation potential of plant species in removing heavy metals in the contaminated soils within the gold mining concession areas. Therefore, this study assessed and classified the phytoremediation potentials of selected plant species around gold mining areas in restoring the environments contaminated by heavy metals. The geographic focuses of the study were the Golden Pride Gold Mine (GPGM) and Geita Gold Mine (GGM) in Tanzania. The shoots and roots of plant species surrounding the mining areas and the samples of associated soils were collected and analysed for total concentrations of lead (Pb), chromium (Cr), cadmium (Cd), copper (Cu), arsenic (As), manganese (Mn) and nickel (Ni) using Atomic Absorption Spectrophotometer (AAS) and UV-VIS spectrophotometry. Routine soil analysis was performed to provide an impression of the fertility status of soils in these gold mining areas. Further, the plants were classified based on their ability to accumulate or exclude heavy metals from the soils. Results indicated that the soils from study areas were loamy textured and slightly acid (pH 6.1–6.5), soil organic carbon and organic matter were low (0.6–2.0%), total nitrogen was very low (<0.10%), phosphorous ranged from low (6–12 mg kg-1 soil) to high (13–25 mg kg-1 soil), and cation exchange capacity ranged from low (6.0–12.0 cmol(+) kg-1 soil) to medium (12.1–25.0 cmol(+) kg-1 soil). In assessing heavy metals using plant parts, the roots of giant rats-tail grass (Sporobolus pyramidalis) accumulated highest Pb (757.78 µg g-1), Creeping Blepharis (Blepharis maderaspatensis) Cd (158.11 µg g-1), lantana (Lantana camara) As (68.61 µg g-1), and leuceana (Leucaena leucocephala) accumulated higher Mn (2734.61 µg g-1) and Ni (4464.33 µg g-1). In shoots, L. leucocephala accumulated higher Cr (1276.67 µg g-1) and higher Cu (2744.44 µg g-1) in L. camara. Results indicated that S.pyramidalis and L.camara are hyper-accumulators of Pb and Cu, respectively. No hyper-accumulator of Cr, Cd, As, Mn and Ni in the areas. Results further revealed that S. pyramidalis, Natal grass (Melinis repens), L. camara, L. leucocephala and B. maderaspatensis are potential phytoremediators, as were either accumulators or excluders of Pb, Cr, Cd, Cu, As, Mn and Ni. Although S. pyramidalis, M. repens, L. camara, B. maderaspatensis and L. leucocephala are likely to pose hazards to herbivores (grazing animals) while entering the food chain, they are still the potential phytoremediators in decontaminating of metalliferous affected ecosystems.

Monitoring of the Contents of Manganese, Zinc, and Copper in Soils and Plants of the Central Chernozemic Region of Russia

The paper discusses the data obtained in 2015–2018 by the State agrochemical monitoring of soils in Belgorod oblast. The research revealed that organic fertilizers are the main source of microelements entering phytocenoses. They are responsible for 79.2% manganese, 87.3% zinc and 84.2% copper of their total amount introduced with fertilizers and ameliorants. The Ap horizon of the ordinary chernozem (Haplic Chernozem) in the steppe zone contains 1.15, 1.18, and 1.14 times more manganese, zinc, and copper, respectively, than the typical chernozem (Haplic Chernozem) in the forest—steppe zone. The studied microelements show the biophylic accumulation in the arable layer. The average total content of manganese, zinc, and copper in the Ap horizon was higher than that in CCa horizon in 1.49, 1.17, and 1.22 times, respectively, in the typical chernozem; and 1.42, 1.22, and 1.16 times in the ordinary chernozem, respectively. The results of continuous monitoring proved that 38.6; 98.7, and 98.2% of the studied arable soils manifest a low supply with manganese, zinc, and copper, respectively. The highest content of manganese was found in grain (1053 mg/kg) and straw (841 mg/kg) of white lupine; that of zinc (43.5 mg/kg), in the grain of the same crop; and the maximal amount of copper was found in the soybean grain (10.5 mg/kg). The lowest accumulation of manganese (9.22 mg/kg) and zinc (26.45 mg/kg) is typical for pea grains, and that of copper, for winter wheat grains (3.60 mg/kg). The concentration of microelements was higher in grains than in straw of winter wheat, soybean and white lupine; whereas the inverse relationship was found for pea plants.

The kinetic parameters of the smoke gases purification process from carbon monoxide on a zeolite-based manganese oxide catalyst

A modified MnO 2 clinoptillolite was obtained by using the available zeolite rock from the Sokyrnytsia deposit (Khust district of the Zakarpattia region, Ukraine) using a simple technique of mixing solutions containing separately Mn 2+ and MnO 4 - . It was determined that the total manganese content in the air-dry modified thermally untreated clinoptyllolite was 11.42 mg/g, which is 1.8 % in terms of MnO 2 . Structural characteristics, namely, the pore size distribution and specific surface area as the main basic characteristics of the catalyst, were studied, which were obtained from the isotherms of low-temperature nitrogen adsorption-desorption. These studies are necessary to determine the limiting stage of CO oxidation. It has been determined that the kinetics of the oxidation process is described by a first-order equation. Based on the obtained characteristics of the catalyst, the kinetic parameters of the process were calculated, namely, the effective and true rate constants and the activation energy, which is 31 kJ/mol. It has been proved that the oxidation reaction of carbon monoxide on an oxide-manganese catalyst proceeds in the intra-diffusion mode. This makes it possible, using the criterion dependences, namely, the Carberry criterion, which is less than 0.05, to assert that the reaction is not limited by the diffusion of CO from the gas stream to the outer surface of the catalyst. It is shown that the transport of carbon monoxide molecules inside the catalyst granules proceeds in the Knudsen regime. The obtained scientific result in the form of a kinetic description of the catalytic oxidation of carbon monoxide with atmospheric oxygen on a manganese oxide catalyst based on zeolite is interesting from a theoretical point of view. From a practical point of view, the calculated kinetic parameters of this process make it possible to calculate a catalytic CO oxidation reactor

Manganese in the hydrosphere of the Jewish autonomous region: surface water

At present, knowledge about the content of manganese in the surface waters of the Jewish Autonomous Region is becoming more and more relevant, since the development and extraction of iron-manganese ores has already begun in the area of the Bidzhan deposit in the north-west of the region. It is planned to develop iron-manganese deposits in other regions of the autonomy. However, we are not sufficiently aware of the migration of this element, its spread by watercourses along the hydraulic network, the change in the forms of transportation due to the boggy territory of the autonomy, and the possible negative impact on aquatic organisms. The purpose of our work is to study the distribution of manganese in surface watercourses, taking into account the geological features and natural conditions of the Jewish Autonomous Region. The content of total manganese in the surface waters of the Bira River and mainly its northern tributaries located on the territory of the autonomy was determined by the method of atomic absorption spectrophotometry. The article presents the results of determining manganese and iron, as well as indicators that affect their migration ability, in the surface watercourses of the Jewish Autonomous Region for two years. The paper describes and analyzes the natural conditions and geological features of the autonomy that affect the distribution of manganese in its surface waters. As a result of the study, it was revealed that all rivers reflect the specific nature of the natural conditions of their formation. In the watercourses of the northwestern part of the region, draining the foothills of the Small Khingan, the influence of deposits of ferromanganese ores is clearly manifested. In the rivers flowing from the southern spurs of the Bureinsky ridge, manganese ore content is not felt. Bira's sharp turn from the mountainous north to the south, to the Amur, occurs against the background of a contrasting change in the relief and close contact of the river with the adjacent swampy plain. Natural processes and sources of Mn input into river waters change: the input of soluble humid metal complexes from the bog drainage begins.

Determination of total concentration and bioaccessible fraction of metals in tomatoes and their derivatives by MIP OES

This study presents information about the total concentration and bioaccessible fraction of barium (Ba), calcium (Ca), cadmium (Cd), copper (Cu), iron (Fe), mercury (Hg), potassium (K), lithium (Li), magnesium (Mg), manganese (Mn), molybdenum (Mo), lead (Pb) and zinc (Zn) in different cultivars of tomato (Gaucho, Paulista, Italiano and Cherry) and their derivatives (sauce and tomato extract). The determinations were performed by microwave induced plasma optical emission spectrometry (MIP OES). The bioaccessible fraction of the elements was evaluated through in vitro digestion process and the concentrations varied between 25 and 100 % ​for Cu, Fe, Mn and Zn, depending on the type of tomato sample and its derivatives. The total concentrations for all the elements studied were below the recommendation of dietary guidelines. For Ba, only the Italiano sample presented 22 % of bioaccessibility. For Pb, the highest percentage of bioaccessible fraction was found in sauces and tomato extracts. The elements Cd, Hg, Li and Mo presented concentrations lower than the limit of detection for the bioaccessibility method.

Effects of mining and reduced turnover of Ephemeroptera (Insecta) in streams of the Eastern Brazilian Amazon

Mining operations can cause environmental alterations that have a major impact on aquatic organisms. In the present study, we analyzed the effects of mining operations on the environmental heterogeneity of streams in the eastern Brazilian Amazon, and the beta diversity (and components) of the local communities of the order Ephemeroptera. We tested three hypotheses: (a) mining activities reduce the environmental variation of streams; (b) altered streams have lower beta diversity, and (c) environmental variables influence the genus richness and abundance of ephemeropterans. The ephemeropterans were sampled in the Carajas National Forest in the dry season over 3 years. Streams were sampled in areas near the extraction of iron ore (16) and in pristine environments (8). The beta diversity was estimated based on the occurrence and abundance approaches. We recorded 2259 individuals and 32 genera. The comparative assessment of environmental variables indicated that environments altered by mining have higher total manganese and iron concentrations than preserved environments. Environmental variables influenced ephemeropteran communities, and the analysis of the components of the beta diversity indicated a higher turnover of ephemeropterans in preserved streams, which implies that species substitution rates are higher in preserved streams than in altered streams. These results indicate that the substitution of species in preserved streams is limited spatially, probably linked to the sensitivity of the organisms to oscillations in the environmental variables occurring in impacted environments. IMPLICATIONS FOR INSECT CONSERVATION: The results indicated that possibly the changes brought about by mining activities restrict the turnover of species between the preserved and altered areas, and only species tolerant to these changes were established. Over time and with the advancement of mining activities may occur the local exclusion of the most sensitive species and homogenization of the composition formed by more tolerant and less relevant conservation species.

Impact of Copper Fungicide Use in Hop Production on the Total Metal Content and Stability of Wort and Dry-Hopped Beer

Transition metals, including copper, iron, and manganese, are known to catalyze the generation of reactive oxygen species (ROS) in beer leading to reduced product stability. Metals in beer are generally derived from raw ingredients. The present study aims to evaluate the impact of brewing and dry-hopping using hops treated with copper-based fungicides (CBFs) on the final transition metal content of model buffer solutions and pilot-scale systems of wort and beer. Copper levels in model wort and beer solutions were elevated (105.6% and 230.4% increase, respectively) when CBF-treated hops were used. In laboratory-prepared wort, elevated copper concentrations were not observed when CBF-treated hops were used for boiling. Dry hopping of beer using CBF-treated hops led to significant increases in total copper content (ca. 75 µg/kg vs. ca. 40–50 µg/kg in the control-hopped beer) when yeast was absent from the treated beer, but not when yeast was present. It was observed that manganese levels were significantly elevated in all hopped beers (ca. 495–550 µg/kg vs. 90–125 µg/kg in the unhopped control), regardless of hop treatment. A hop varietal thiol, 4-Mercapto-4-methylpentan-2-one, was spiked into treated beers, and the rate of oxidative loss was monitored during aging. Rates of thiol loss in treated beer samples did not differ across CBF treatments but were significantly lower in unhopped controls in the absence of yeast (p &lt; 0.0001) and correlated significantly with total manganese content of the beers (R2 = 0.4228, p = 0.0006). The rate of staling in hopped beers as measured by the rate of 1-hydroxyethyl radical generation did not differ among hop treatments, suggesting that excess copper content contributed from the hops does not negatively impact the oxidative stability of the beers. These findings suggest that brewers can use CBF-treated hops without any negative implications for the shelf stability of their beers and do not contraindicate the use of CBF in hops production when necessary.

Caracterização química do solo em uma área de recuperação de um depósito de metalurgia de zinco

Ore processing generates a large amount of sterile and waste from purification and concentration processes. This material, in contact with the environment, can cause major environmental impacts. CMM-Votorantim at Três Marias benefits silicate and sulphide Zn ores. The tailings from one stage of the process are deposited in an area called PH9 on the banks of the São Francisco River and subsequently removed and placed in a waterproofed settling basin. The area of the old deposit presented problems in the process of environmental recovery and, therefore, it became opportune to investigate chemically the level of contamination there. The area has 14.4 ha and is located in the municipality of Três Marias / MG with a slope towards the bed of the São Francisco River. The soil samples were collected in two cross profiles, one North - South and the other East - West, totaling 29 georeferenced points with a distance of 20 m. A soil sample was collected at each point. After preparation at the Soil Laboratory of Unimontes, Campus Janaúba - MG, the samples were analyzed in the ICP OES laboratory of the NGqA of the CPMTC of UFMG - Campus Belo Horizonte. Total and available concentrations of calcium, magnesium, aluminum, iron, manganese, copper, zinc and organic matter, together with pH were determined. For the graphical representation, we opted for a grouping the results in pH ranges versus concentrations. The results show that the area has magnesium contamination, thus causing severe structural degradation of the soil. The concentrations of the other elements in the PH9 area are within the limits allowed for land use in agricultural activity, but approaching the upper limit allowed.

Effect of Buckwheat Groats Processing on the Content and Bioaccessibility of Selected Minerals.

Adequate supply of minerals in the diet is necessary for the proper functioning of the human body. In recent years gluten-free diet, which rigorous forms may lead to deficiencies of mineral components (especially Mg, Mn, Zn and Cu), is becoming more and more popular. Buckwheat grains do not contain gluten, and their nutritional value is very high. They are often consumed in the form of groats, which are obtained from roasted and dehulled seeds. The purpose of the work was to determine how conducting the buckwheat groats production in industrial conditions affects the content and availability of magnesium, manganese, zinc and copper. The results indicated that husk removal had a particularly adverse effect on the total manganese content and its amount released by enzymatic digestion, whereas it had a positive effect on the post-digestion zinc level by increasing it by nearly half. Hydrothermal processes especially affected the release of analysed elements simulated by the in vitro method, and the extent of changes depended on the processing parameters. It was shown that bioaccessibility of minerals may be increased by treating buckwheat at a lower temperature for a short time, which has a particularly beneficial effect on the manganese and magnesium. Treating grains at a higher temperature reduces the bioaccessibility of all analysed elements, which was particularly noted for zinc and copper. Based on the obtained results, it should be stated that buckwheat groats should be a regular part of human diet, because they are a good source of easily digestible mineral compounds. Their consumption should be especially considered by people on a rigorous gluten-free diet, as they can prevent mineral deficiencies associated with its use.

Estimated Contributions of Rooibos Tea to the Daily Manganese and Zinc Intakes Determined in Tea Leaves and Tea Infusions by Inductively Coupled Plasma-Mass Spectrometry.

Rooibos tea, scientific name Aspalathus linearis, is a popular tea grown in South Africa and consumed worldwide for its unique taste and presumed health benefits. There is a growing interest in using rooibos tea as a supplement for the deficiency of metallic nutrients in South Africa. In this study, the total concentrations of manganese (Mn) and zinc (Zn) in acid-digested tea leaves and the corresponding tea infusions were determined by inductively coupled plasma-mass spectrometry (ICP-MS) to estimate the contribution of rooibos tea consumption to the recommended daily allowance (RDA) of Mn and Zn in consumers. The accuracy of microwave-assisted acid digestion and tea infusion methods were checked by analyzing INCT-TL-1 tea leaves certified reference material (CRM) and samples spiked with standards, respectively. Both methods yielded quantitative percentage recoveries for Mn and Zn. Rooibos tea leaves and the corresponding infusions are composed of higher levels of Mn than Zn where 40.9 to 85.7 μg Mn/g and 4.15 to 12.2 μg Zn/g were found in digested tea leaves and 11.8 to 30.2 μg Mn/g and 1.51 to 4.59 μg Zn/g in tea infusions. These results indicate the contribution of about 1.0 to 3.2% Mn and 0.03 to 0.08% Zn in males approximately ≥ 9 years of age and 1.3 to 3.8% Mn and 0.04 to 0.11% Zn in females of the same age group as males of the RDA from drinking a cup of tea obtained by infusing a 2-g bag of rooibos tea.

Assessment of heavy metals in Cypress (Thuja orientalis L.) in the Yazd Highway green belt

Dust storm is one of the criteria for air pollution, and pollution by Heavy Metal(HM) is one of the major environmental problems in the world. The objective of the present study was to assess some of HMs concentrations in the leaves and bark of cypress and atmospheric falling dust along the Yazd highway, Yazd Province, Iran. The total concentrations of cadmium (Cd), cobalt (Co), copper (Cu), nickle (Ni), lead (Pb), zinc (Zn), iron (Fe) and manganese (Mn) in the dust and plant samples were measured using atomic absorption spectrophotometry after digestion with acid. The results showed that the concentration of Zn and Cd metals in falling dust were the highest to the lowest, respectively. The distance from the highway significantly influenced the concentration of HMs in leaves and bark of the cypress tree. Moreover, the effect of HMs on the bark of this tree was higher than that of leaves, except for Cd, Co, Cu and Mn. Concentrations of Zn, Co, Ni and Fe increased with the increase in the distance from the highway due to multi-directional winds and the presence of other contaminants. The Pearson correlation analysis between the HMs found in the falling dust and Thuja orientalis L. showed that the input and controlling factors of these metals in the cypress tree were probably the same as the dust. The results further showed that the Thuja orientalis L. leaves with a metal accumulation index of 1973.16 mg/kg were more able to simultaneously absorb different metals. Therefore, since this green belt surrounds the Yazd urban area, it is expected that a significant amount of HMs will be absorbed by these trees.

Prevention of mineral metabolism of disorders in lactating rabbits

Considerable damage to rabbit breeding is caused by the loss of production by eating or trampling newborn rabbits by their mothers. The main reason is the weakening of the organism due to deficiency of nutrients (high quality protein) and of biologically active substances in the diet. It is relevant today to search for non-toxic and highly effective complex preventive drugs, which have a positive effect on the mineral metabolism in animal organism. The research was carried out on the farm of Kyiv region. We studied the morphological parameters of blood by standard methods and the biochemical parameters of blood using semi-automatic biochemical analyzer with standard reagent kits. The content of chemical elements in blood plasma was investigated by the method of atomic emission spectrometry with inductively coupled plasma using Optima 2100 DV device. The paper presents the research on determining the biochemical status of an organism of lactating rabbits at the prevention of microelementosis using a new experimental eco-friendly drug. The content of total protein, albumin, glucose, total calcium, inorganic phosphorus, total bilirubin, urea, creatinine, TBA-active products, iron, manganese, copper, zinc, cobalt and activity of ALT, AST, ALP, GGT and Catalase in rabbits blood in the first,15th and 30th day for the use of the biologically active additive “Huminorm plus” is determined. In rabbit blood at the use of the “Huminorm plus” with water for watering for 15th days of the experiment, the content of hemoglobin was 1,2 times higher, phosphorus inorganic was 2.2 times higher, urea was 1.3 times higher, manganese was 3.6 times higher, cobalt was 2.6 times higher, cooper was 1.2 times higher and zinc was 1.6 times higher, compared to the first day of the experiment. In rabbit blood at the use of the “Huminorm plus” with feed for 30th days of the experiment, the number of red blood cells was determined to be 7 % higher, content of hemoglobin was 1.4 times higher, total protein was 1.2 times higher, urea was 1.3 times higher, calcium was 1.4 times higher, manganese was 3.1 times higher, zinc was twice higher, iron was 2.5 times higher, cobalt was 2.5 times higher, cooper was 1.7 times higher and alkaline phosphatase activity was 1.7 times lower, compared with the first day of experience. We defined the positive influence of the prophylactic drug on the indicators of hematopoiesis, metabolism of proteins and minerals in lactating rabbits. The development of ecofriendly, non-toxic substances for the prevention of mineral disbolism among rabbits is a promising area of research.

Elec-accumulating behaviors of manganese in the electrokinetics-processed electrolytic manganese residue with carbon dioxide and oxalic acid

An electrokinetic treatment for the accumulation of manganese in electrolytic manganese residue (EMR) was investigated. Electrokinetic experiments were conducted in a self-made electrokinetic device with CO2 bubbled into the cathode region as well as deionized water (EKCa), Na2SO4 (EKCb), Na2C2O4 (EKCc) and H2C2O4 (EKCd) pretreating the EMR, respectively. The potential difference, the pH, the accumulated content of manganese, the manganese fractionation and the energy consumption were investigated during the electrokinetic experiments. The results revealed that the accumulated content of manganese at the cathode region during the electrokinetic experiments with CO2 and different pretreating reagents was higher than that during the direct electrokinetic experiment. The manganese content of the cathode region increased gradually with an increasing electrokinetic time during EKCa, EKCb, EKCc and EKCd. The total manganese content and the combinative exchangeable and carbonate content at the cathode region had the maximum 7.5% and 6.3%, respectively, during EKCd, and the energy consumption per gram accumulated manganese of EKCd was lowest. These patterns were because CO2 reacted with OH − ions generated at the cathode region to produce CO32− ions and reduced the resistance, and CaMn2O4 from the EMR was reduced to Mn2+ ions by H2C2O4 in acidic regions.

Evaluation of source of corn silage and trace minerals on lactational performance and total-tract nutrient digestibility in Holstein cows

We evaluated the effects of source of corn silage and trace minerals on lactational performance and total-tract digestibility (TTD) of nutrients in 16 Holstein cows averaging 82 (standard error = 3) days in milk in a replicated 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments with 28-d periods. The diets consisted [dry matter (DM) basis] of 55% conventional (CON) or brown midrib-3 (BM3) corn silage, 2% chopped wheat straw, and 43% grain mix with either sulfate (STM) or hydroxy (HTM) sources of copper, manganese, and zinc trace minerals. The targeted supplemental concentrations of copper, zinc, and manganese were 194, 1,657, and 687 mg/d, respectively. The dietary treatments were CON-STM, CON-HTM, BM3-STM, and BM3-HTM. The dietary nutrient composition of the BM3 diets averaged 32.1% amylase neutral detergent fiber on an organic matter basis (aNDFom) and 6.9% undigested neutral detergent fiber at 240 h (uNDF240om; % of DM), and CON diets averaged 36.2% aNDFom and 8.6% uNDF240om (% of DM). The average supplemental concentrations of copper, zinc, and manganese for the STM diets were 10, 41, and 64 mg/kg, respectively, and the average supplemental concentrations of copper, zinc, and manganese for the HTM diets were 10, 40, and 62 mg/kg, respectively. The average total dietary concentrations of copper, zinc, and manganese for the STM diets were 17, 104, and 60 mg/kg, respectively, and the average total dietary concentrations of copper, zinc, and manganese for the HTM diets were 17, 91, and 66 mg/kg, respectively. Data were summarized by period and analyzed as a replicated Latin square design with fixed model effects for corn silage, trace minerals, corn silage × trace mineral interaction, period within replicated square, and replicated square using the MIXED procedure of SAS. Cow within replicated square was a random effect. Cows fed the BM3 diets had greater dry matter intake (DMI) and milk yield (28.1 and 47.0 kg/d) than cows fed the CON diets (27.5 and 44.7 kg/d). We found no significant interaction between corn silage and trace minerals for DMI and milk yield. Cows fed the HTM diets (28.1 kg/d) had a greater DMI than cows fed the STM diets (27.5 kg/d). Cows fed the BM3 diets had greater TTD of DM and OM (72.8 and 74.1% of DM) than cows fed the CON diets (71.1 and 72.3% of DM). Cows fed the HTM diets had a tendency for greater TTD of aNDFom than cows fed the STM diets (56.8 vs. 54.9% of DM). Cows fed the CON diets ruminated longer during the day than cows fed the BM3 diets (524 vs. 496 min/d). Corn silage with greater NDF digestibility and lower uNDF240om enhanced DMI, milk yield, and TTD of DM and OM, and hydroxy trace minerals improved DMI and tended to improve TTD of aNDFom. The source of corn silage and trace minerals should be taken into consideration when formulating diets for high-producing dairy cows.

Effects of Chitosan on the Uptake of Total Iron, Manganese and Boron in Peach Seedlings

As materials for the study, peach seedlings were sprayed with various concentrations (0, 1, 2, 4 and 6 g/L) of chitosan for the sake of the uptake of total iron, manganese and boron content and a more particular knowledge of the growth of the seedlings. The results in experiment showed that the total manganese content accumulated more in peach seedlings compared with other two elements. The total manganese and boron content in roots and leaves of chitosan-treated seedlings could increase in general. In the wake of the chitosan concentration increased, the total iron content in roots and leaves of seedlings gradually decreased but increased in stems. When it comes to the absorption of nutrients by peach seedlings, there were existing synergism and antagonism in this experiment among iron, manganese and boron, which were good for the growth of peach seedlings.

Safety and efficacy of Manganese chelates of lysine and glutamic acid as feed additive for all animal species.

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of manganese chelates of lysine and glutamic acid (Manganese‐LG) as nutritional feed additive for all animal species. The EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) Panel was assigned to this mandate. The Panel concluded that, owing to safety considerations, the simultaneous use of both feed and water supplemented with Manganese‐LG should be avoided. Manganese‐LG showed to be safe for chickens for fattening up to the maximum authorised levels in the EU for manganese in feed (150 mg/kg); however, since a margin of safety could not be derived, the conclusions could not be extrapolated/extended to other categories/species. The data showed that Manganese‐LG does not increase nor change the patterns of manganese tissue deposition when administered up to the maximum level allowed in the EU; therefore, the Panel concluded that the additive is safe for consumers of tissues and products from animals fed the additive up to the total manganese content in feed authorised in the EU. Owing to the manganese and nickel content of Manganese‐LG, the Panel concluded that the handling of the additive poses a risk to users by inhalation and shall be considered as a skin and respiratory sensitiser; the data showed that the additive is irritant to eye and non‐irritant to skin. Manganese‐LG, intended to substitute other authorised manganese additives, will not further increase the environmental burden of manganese; the Panel considered that the use of the additive in animal nutrition would not pose an additional risk for the environment. The Panel concluded that the additive is efficacious in chickens for fattening; this conclusion can be extrapolated/extended to other categories/species. The FEEDAP Panel posed a recommendation concerning the description of the additive.

Assessment of cadmium and lead contamination in rice farming soils and rice (Oryza sativa L.) from Guayas province in Ecuador

Rice is the world’s most consumed and in-demand grain. Ecuador is one of the main rice-consuming countries in Latin America, with an average per capita consumption of 53.2 kg per year. Rice cultivation takes place under flooding conditions, which favors the mobilization and subsequent accumulation of heavy metals in the plant. This study’s principal objective was to evaluate the contamination of cadmium (Cd) and lead (Pb) in the rice cultivation system in the province of Guayas. To this end, extensive sampling of water, soil and rice grains was carried. Water samples were analyzed to determine physicochemical properties and concentrations of dissolved Cd and Pb. Physicochemical properties, total organic carbon (TOC), total content of nitrogen (N), iron (Fe), manganese (Mn), phosphorus (P), bioavailable phosphorus (P mehlich), Cd and Pb were determined in soil samples. In addition, to understand the dynamics of Cd and Pb mobility and bioavailability, an extraction of six randomly selected soil samples was carried out. The concentration values of the total Cd and Pb content in the rice cultivation system did not exceed the maximum recommended limit for soil, water and rice grains. However, 85% of the total Cd was in the soluble or exchangeable fraction of the soil, while the Pb was strongly bound to crystalline iron oxyhydroxides. It was established that the TOC, N, Fe, and P mehlich have a significant correlation (p < 0.05) with the overall concentration of Cd and Pb in the rice farming soil. The Cd and Pb present in rice do not represent a dietary health risk to the population of Ecuador.

Content of heavy metals and petroleum products in the soil on the territory of oilproducing areas of the Republic of Tatarstan

The paper presents data on the hygienic assessment of the content of heavy metals and petroleum products in the soil on the territory of oil-producing areas of the Republic of Tatarstan. The average total content of lead (10,1 mg/kg), cadmium (0.073 mg/kg), manganese (792.4 mg/kg), cobalt (14.2 mg/kg), chromium (87.6 mg/kg), nickel (65.2 mg/ kg), arsenic (8.0 mg/kg), copper (36.6 mg/kg) and zinc (521 mg/kg) in soil for agricultural purposes near objects oil production was shown not to exceed the established hygienic standards. Soil contamination with oil products leads to an increase in its toxicity and mutagenicity. Soil contamination with oil products at the level of as low as 30 mg/ kg leads to the gain in its toxicity (low toxicity) and mutagenicity (average) (specific gravity of germinated seeds was 70.7±0.67%, aberrations - 1.78±0.19%).

Determination of heavy metal pollutions in the atmospheric falling dust by multivariate analysis

The purpose of this study was to assess some heavy metal (HM) concentrations in the soil and atmospheric falling dust along the Yazd highway, Yazd Province, Iran. The total concentrations of cadmium (Cd), cobalt (Co), copper (Cu), nickle (Ni), lead (Pb), zinc (Zn), iron (Fe) and manganese (Mn) in the dust and soil samples were measured using atomic absorption spectrophotometry after digestion with acid. The relationship between HMs in the falling dust was determined using correlation coefficients, principal component analysis and cluster analysis. The mean concentrations of HMs in falling dust were higher than those of the nearby soils, except for Fe, Pb and Zn. The highest correlation between HMs in the falling dust and soil was associated with Cd and Fe as well as Cd and Ni with the correlation coefficients of 0.81 and 0.97, respectively. Based on the principle component analysis, cluster analysis and correlation coefficients, two resources were identified for HM concentrations in the falling dust. The measurement of enrichment factor exhibited that the region dust infiltration of metals on Mn (13.46), Zn (8.16) and Cu (5.21) are grouped in the severe enrichment class. Increasing industrialization and human activities lead to enter intensified levels of HMs into atmosphere. So, implementation of environmental standards and improvement of public transportation are necessary to reduce the level of pollutants entering the atmosphere.

A Zinpyr-1-based Fluorimetric Microassay for Free Zinc in Human Serum.

Zinc is an essential trace element, making it crucial to have a reliable biomarker for evaluating an individual’s zinc status. The total serum zinc concentration, which is presently the most commonly used biomarker, is not ideal for this purpose, but a superior alternative is still missing. The free zinc concentration, which describes the fraction of zinc that is only loosely bound and easily exchangeable, has been proposed for this purpose, as it reflects the highly bioavailable part of serum zinc. This report presents a fluorescence-based method for determining the free zinc concentration in human serum samples, using the fluorescent probe Zinpyr-1. The assay has been applied on 154 commercially obtained human serum samples. Measured free zinc concentrations ranged from 0.09 to 0.42 nM with a mean of 0.22 ± 0.05 nM. It did not correlate with age or the total serum concentrations of zinc, manganese, iron or selenium. A negative correlation between the concentration of free zinc and total copper has been seen for sera from females. In addition, the free zinc concentration in sera from females (0.21 ± 0.05 nM) was significantly lower than in males (0.23 ± 0.06 nM). The assay uses a sample volume of less than 10 µL, is rapid and cost-effective and allows us to address questions regarding factors influencing the free serum zinc concentration, its connection with the body’s zinc status, and its suitability as a future biomarker for an individual’s zinc status.