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Manganese is one of the most frequently used materials in industry, hence its elevated levels in the surrounding environment. Manganese is an essential nutrient, important in biochemical reactions of several enzymes; on the other hand, it can cause both acute and chronic diseases (eg. manganism). The importance of manganese in living systems remains poorly explored. Manganese compounds share with certain other elements the property of being essential for life, but certain manganese species and large doses are toxic. Manganese plays an important role in iron metabolism and is required for the brain’s normal function. Chemical speciation is an important subject in the environmental protection as well as in toxicological and analytical research because toxicity, availability and reactivity of trace elements depend on the chemical forms in which they occur. This study deals with effects of manganese and manganese speciation forms on living organisms, particularly in aquatic environments. The review presents manganese speciation methods using sophisticated hyphenated techniques.The hyphenated techniques, in which a separation method is coupled with multi-dimensional detectors, have become a useful alternative. These techniques allow for a qualitative and quantitative analysis of the sample composition, wherein manganese may be present in various speciation forms. The article provides many examples of the hyphenated technique application in manganese speciation analysis.
Soil iron and manganese fractionation is evaluated in the soil profile sampled from a pine-covered area of Wielkopolski National Park (mid-western Poland), that for years has been exposed to acid rain. The soils studied are sands and loamy sands with a pH of 3.3-4.4. The content of iron and manganese was analyzed by sequential extraction in the following fractions: exchangeable, acid extractable, reducible, oxidizable, and residual. The soil profile displays a lithogenically dichotomous structure that is reflected in the iron and manganese content, especially in the Fe residual fraction and Mn oxidizable fraction. In terms of the lability of manganese, it can be stated that the amount of manganese in reducible fractions (Mnred) is higher than in exchangeable and acid extractable ones (except in the surface layer), while the amounts of manganese in fractions in which it is poorly available (Mnox) and unavailable (Mnres) are lower than that of Mnred. For iron, this sequence looks as follows: Feex
The accumulation of elements in biocenoses of aquatic ecosystems depends primarily on the forms of elements in the environment. The bioaccumulation coefficient (BC) is a measure of the intensity of an elements uptake of trace by living organisms. Manganese is an essential element for both plant and animal organisms. However, its excess may cause a toxic effect, i.e. it disturbs the activity of synapses, thus leading to an impaired functioning of the central nervous system. This study focused on the accumulation of manganese in individual links of an aquatic ecosystem food chain under conditions of extensive carp farming. The BC values were computed and the pollution degree of the fish pond was estimated. The investigations were conducted in a fish pond situated in Mydlniki and fed with water from the Rudawa River. Water, bottom sediment, benthic organisms (Diptera Chironomidae larvae) and carps were sampled from the pond. Organs most strongly involved in the metal metabolism (gills, gonads, liver and muscles) were prepared from sampled carps. Manganese concentrations were determined in all samples using atomic emission spectroscopy after wet mineralization of samples in a closed system in a microwave mineralizer. The concentrations of manganese in the abiotic elements of pond ecosystems were low and should not pose any threat of its excessive accumulation in living organisms. However, the manganese concentrations in the benthic organisms and in the analyzed carp organs were high. Similarly, other authors found high manganese concentration in fish living in the environments polluted with this element. The value of manganese enrichment coefficient for the bottom sediments in relation to its water concentration was high. The biggest manganese content was assessed in gills, then in the liver and gonads, and the smallest one - in carp muscles. Manganese BCs in the gills of carps in relation to its content in water and bottom sediments were 176.6 and 0.08, respectively. The BC values in relation to the manganese concentration in water were much higher, but lower in comparison to its content in bottom sediments than reported elsewhere. This confirms that the BC for manganese in gills varies depending on the water pollution level.
In 1996, a field experiment was set up on class IIIa soil, which consisted of 6 trials: 1 – bare fallow, 2 – fallow land seeded with annual plants, 3 – field swarded with goat’s rue (Galega orientalis Lam.), 4 – traditional fallow, 5 – field swarded with a mix of goat’s rue (Galega orientalis Lam.) and aweless brome (Bromus inermis), 6 – field swarded with aweless brome (Bromus inermis). During the tests, no agrotechnical measures were carried out apart from periodical mechanical weeding of the bare fallow and the sowing of annual plants. Plant samples for chemical analyses were taken from the swarded fields; the remaining biomass was left on the fields. After each growing season, soil samples were collected in four replicates from the 0-25 cm and 25-50 cm soil horizons, for determination of the content of Cu, Zn and Mn available forms. This paper discusses the results obtained in 2000-2007. The experiment has demonstrated that the way farmland was laid fallow or set-aside had an effect on concentrations of the available forms of Cu, Zn and Mn in the 0-25 and 25-50 cm soil horizons. Particularly large changes occurred in the levels of Zn and Mn. The way set-aside arable land was kept had a weaker influence on the concentrations of easily soluble forms of copper. By seeding annual plants and leaving the grown biomass on a set-aside field, it was possible to maintain the soil abundance of available Zn on a high level and that of Cu and Mn – moderately high. Keeping soil as bare fallow favoured better accumulation of available forms of copper and manganese.
A method for blood manganese measurements has been described. The method provides high reproducibility of the concentrations measured. The coefficients of variation were 3.4% and 4.1 % for within-run and between-runs, respectively. The recovery of the method was 98.1 %. Manganese concentrations in the blood ranged from 6.27 ng/ml to 8.98 ng/ml. The measurements revealed that contamination of tubes containing samples and prepared for determination can be the cause of the divergence of the results obtained.
This paper presents investigation results which evaluate the role of biological processes in elimination of Mn (II) and NH4+ ions from groundwater. The raw water containing up to 1.4 mg/dm3 manganese and up to 2.9 mg N/dm3 ammonia nitrogen after aeration was treated using first and second stage sand filters at the "Letniki" water treatment plant near Elblag. Both ions were removed with high efficiency and the concentrations of these components after two stages of filtration were lower than the admissible values for drinking water in Poland (0.1 mg Mn/dm3 and 0.5 mg N-NH4/dm3). It was found that physico-chemical and biological processes were responsible for ammonia nitrogen elimination, while catalytic processes (physico-chemical and biological) contributed to manganese removal.
Trace elements are important in appropriate organisms functioning. Among them manganese as well as silicon play essential roles. Manganese takes parts in composition of many enzymes, it is a cofactor of numerous enzymatic reactions, a structural element of skin and bones, it also prevents osteoporosis. Its very important role in reproduction processes and in central nervous system has been already stated. Silicon is a very important factor, which takes active part in vital processes, regenerating tissues and increasing general immunity of organism. It has basic meaning in metabolism of connective tissue, collagen formation and bone development and mineralization, cartilages, hair, nails, teeth in human and animals, and also in processes of convalescence and ageing of organism. The aim of our experiment was to estimate influence of manganese chloride on the concentration of silicone in mice tissues. It has been find out that doses of administered manganese as well as the duration of exposure have influence on silicon content in tissues.
The objective of this study has been to follow modifications in the content of Cu, Zn and Mn in the topmost layer of soil which had been fertilized for many years with farmyard manure and mineral fertilizers or with mineral fertilizers alone. Soil samples were collected in 2002-2005 from a trial established in 1986 on proper brown podsolic soil, according to the random block design with four replication. The first factor consisted of organic fertilization (manure applied every two years or without manure). The second factor involved different rates of mineral fertilization. Rates of nutrients in the mineral fertilizers were identical in both experimental series – with or without manure. In each year, the same crop was grown on both fields, in a crop rotation system: sugar beet (2002), spring barley (2003), maize (2004) and spring wheat (2005). Plant available forms of nutrients were extracted from soil in 1 mol HCl dm-3 solution. After extraction, the content of metals was determined by atomic absorption spectrophotometry. The results underwent statistical processing using analysis of variance for a two-factor experiment. The content of available forms of copper, zinc and manganese in soil regularly amended with manure was evidently higher than analogous concentrations determined in soil receiving only mineral fertilization since 1986. Manure most strongly improved the concentration of Cu (nearly 1.7-fold), while producing the weakest influence on manganese (over 1.3-fold more). In absolute values, however, the increase in availability of manganese was the highest, reaching on average 52 mg kg-1 of soil. Differentiated mineral fertilization with nitrogen or potassium as well as manganese and liming to a lesser extent than manure modified the availability of Cu, Zn and Mn in soil. Among these nutrients, nitrogen most often increased the content of plant assimilable forms of metals in soil, which may have been caused by its acidifying influence.
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