Zachowanie Cd, Cr, Cu, Pb i Zn w glebach napływowej i brunatnej nawożonych kompostami

Risk elements contents play important role in compost quality determination. The aim of the work was to evaluate main risk elements availability in two soils with various parameters after composts application. The changes of risk elements mobility in soils fertilized with composts differed in dependence on soil parameters (risk elements contamination of soil, clay particles content, organic matter content and pH value) and on used extraction agent. Cadmium, zinc and partly chromium extracted in 0.01 mol o dm^-3 CaCl2 solution were immobilized and lead was released to soil solution of both soils. The remediation ability of composts in cadmium and lead contaminated soil was found only for cadmium.Zawartość pierwiastków szkodliwych odgrywa ważną rolę w wyznaczaniu jakości kompostu. Celem badań była ocena przyswajalności głównych pierwiastków szkodliwych w dwóch glebach o różnych parametrach po zastosowaniu kompostów. Zmiany mobilności tych pierwiastków w glebach nawożonych kompostami różniły się w zależności od właściwości gleby (zanieczyszczenia gleb pierwiastkami szkodliwymi, zawartości frakcji iłu, zawartości materii organicznej i wartości pH) i od użytego odczynnika ekstrakcyjnego. Kadm, cynk i częściowo chrom ekstrahowane roztworem 0,01 mol CaCl2 o dm^-3 były unieruchamiane, a ołów był uwalniany do roztworu glebowego obydwu gleb. Zdolność remediacyjną kompostu w glebach zanieczyszczonych kadmem i ołowiem stwierdzono tylko w przypadku kadmu

Classical dry ashing of biological and agricultural materials. Part II. Losses of analytes due to their retention in an insoluble residue

Retention of selected analytes (Cd, Cr, Cu, Mn, Pb, Zn) in solid residue which remains undissolved in 1.5% HNO$_3$ used as a leaching medium after classical dry ashing of ten materials (alfalfa leaves, NIST SRM 1569 Brewer's Yeast, blood meal, meat-bone meal, feather-bone meal, silage residue, litter, pond sediment, coal waste, IRM NSC-21 Industrial Compost Vitahum) was studied. The elements remaining in the residue were determined mainly by AAS after dissolution of this residue in the mixture of HF + HNO$_3$. In several instances, pressurized wet digestion, alkaline fusion, stripping voltammetry and instrumental neutron activation were also applied. Increasing concentration of mineral acid in leaching medium which does not contain HF, plus increasing final volume of the solution, suppresses significantly this type of analyte losses in the majority of matrices tested. However, for industrial compost and standard reference material NIST 1569 Brewer's Yeast, application of an HF step is necessary for quantitative release of the analytes (in particular chromium) into solution

Efficiency of extractants to release As, Cd and Zn from main soil compartments

Various soil extraction methods were developed for the determination of total and/or plant-available concentrations of potentially toxic elements. In this experiment, four single extraction procedures (aqua regia, HNO$_3$, acetic acid, DTPA) were tested for the determination of extractable contents of As, Cd and Zn. 35 soils differing in their physicochemical properties and in total element contents were used in this experiment. Extractability of elements from soil samples varied following the individual elements and/or extraction agents used. The strong acids were not able to release the elements tightly bound into the silicate sample matrix. However, such techniques remain utilizable for the approximate determination of “pseudototal” element contents in soil, especially if soil samples are affected by anthropogenic contamination. The concentrations of As, Cd, and Zn determined in soil extracts by both mineral and organic acids covered in most cases the element portion representing more than one soil element fraction determined using SM&T sequential extraction procedure. Solutions of acetic acid and DTPA were able to release a part of the element fraction bound in Fe/Mn oxides and organic matter of soil sample. Arsenic represents an exception because it is not released by DTPA

The risk element uptake by chamomile (Matricaria recutita (L.) Rauschert) growing in four different soils

German chamomile (Matricaria recutita (L.) Rauschert) belongs to the plants with a high tolerance to toxic elements. The ability of chamomile to accumulate risk elements was tested in a pot experiment in which four soils contaminated by different levels of arsenic (As), cadmium (Cd), lead (Pb), and zinc (Zn), differing in their physicochemical parameters, were used. The element mobility in the soils was affected predominantly by the cation exchange capacity (CEC) of the soils. Whereas As, Pb, and Zn were retained in roots, Cd showed good ability to translocate to the shoots, including anthodia, even in extremely Cd-contaminated soil without symptoms of phytotoxicity. The bioaccumulation factor for Cd calculated as the ratio of element content in the plant and the soil was the highest among the investigated elements. Between 5.5 and 35% of the total Cd was released to infusion, and its extractability decreased with increasing Cd content in anthodia. The essential oil composition suggested an alteration of the abundance of the individual compounds. However, no detectable contents of risk elements were found in the oil. Chamomile can be recommended as a suitable alternative crop for risk element-contaminated soils tested within this experiment, but only for production of essential oil

Does Zinc Overdose in Rat Diet Alter Cu, Fe, Mn, and Zn Concentrations in a Tapeworm Host?

We evaluated Cu, Fe, Mn, and Zn concentrations in the bone, muscle, testes, intestine, liver, kidneys and tapeworm parasites Hymenolepis diminuta of rats from four groups: 12 animals given zinc lactate (120 mg/rat and week) in feed mixture (M0 group); six animals given zinc lactate (120 mg/rat and week) in feed mixture and infected with tapeworms (MT group); six control animals fed a standard mixture of ST-1 for rats (00 group); and six control animals fed a standard mixture of ST-1 for rats and infected with tapeworms (0T group). The experiment was conducted over a six-week period. In our study, tapeworm presence decreased element concentrations in the majority of rat tissues. Tapeworms accumulated higher levels of zinc and manganese than did the majority of host tissues; however, they accumulated very little iron and copper in comparison to the host tissues. Zinc overdosing increased manganese concentrations in rat tissues; zinc overdosing also seemed to protect the liver from absorption of Fe by tapeworms

Wpływ kadmu i cynku na metabolizm szpinaku

Changes in metabolism of spinach (Spinacia oleracea L., 'Matador' cv.) plants exposed to stress caused by two heavy metals: cadmium and zinc were studied. The distribution of these elements in biomass (in root, leaf blade, petiole), chlorophyll content and activity of glutamate 5-kinase [E.C.2.7.2.11] the enzyme catalyzing the first step of proline biosynthesis were investigated in pot experiments. Results of the experiment revealed the toxic effects of cadmium and zinc at both tested levels (2.5, 25 mg Cd and 50, 500 mg Zn o kg^-1) for spinach. Under these conditions, decrease of glutamate kinase activity in spinach plants grown on contaminated treatments compared with untreated control was found. Allosteric regulation of glutamate kinase activity by free proline creates a possibility for an increase in glutamic acid content due to the synthesis of glutathione and subsequently phytochelatines in plant cells. For this reason the rates of Cd and Zn applied into soil decreased the glutamate kinase activity. The higher doses of both metals negatively affected yield of spinach dry biomass, but only Cd dose (25 mg Cd o kg^-1 soil) was associated with the significant inhibition of aboveground biomass compared with control treatment (by 14 %). The highest contents of both elements were analyzed in blades of spinach leaves. Chlorophyll content was decreased only by higher cadmium dose.Badano zmiany metabolizmu roślin szpinaku (Spinacia oleracea L., odmiany 'Matador') eksponowanych na stres powodowany przez dwa metale ciężkie: kadm i cynk. W doświadczeniu wazonowym badano rozmieszczenie tych pierwiastków w biomasie (w korzeniach, blaszkach i ogonkach liściowych), zawartość chlorofilu oraz aktywność kinazy glutaminianowej [E.C.2.7.2.11], enzymu katalizującego pierwszy stopień biosyntezy proliny. Wyniki doświadczenia wykazały toksyczny wpływ kadmu i cynku na szpinak w obydwu zastosowanych dawkach (2,5 i 25 mg Cd oraz 50 i 500 mg Zn o kg^-1). W tych warunkach stwierdzono spadek aktywności kinazy glutaminianowej w roślinach szpinaku rosnących w obiektach zanieczyszczonych metalami w porównaniu z obiektem kontrolnych, bez ich dodatku. Regulacja allosteryczna aktywności kinazy glutaminianowej przez wolną prolinę indukuje możliwość zwiększenia zawartości kwasu glutamiowego w wyniku syntezy glutationu, a następnie fitochelatyn w komórkach roślin. Z tego względu dawka Cd i Zn zastosowana do gleby zmniejszyła aktywność kinazy glutaminianowej. Większa dawka obydwu metali ujemnie oddziaływały na plon suchej masy szpinaku, ale tylko dawka 25 mg Cd - kg^-1 gleby wywołała znaczne zahamowanie (o 14 %) wzrostu nadziemnej biomasy w porównaniu z obiektem kontrolnym. Największe zawartości obydwu metali stwierdzono w blaszkach liściowych szpinaku. Zawartość chlorofilu zmniejszyła się tylko po zastosowaniu większej dawki kadmu