From mine to mind and mobiles - Lithium contamination and its risk management.

With the ever-increasing demand for lithium (Li) for portable energy storage devices, there is a global concern associated with environmental contamination of Li, via the production, use, and disposal of Li-containing products, including mobile phones and mood-stabilizing drugs. While geogenic Li is sparingly soluble, Li added to soil is one of the most mobile cations in soil, which can leach to groundwater and reach surface water through runoff. Lithium is readily taken up by plants and has relatively high plant accumulation coefficient, albeit the underlying mechanisms have not been well described. Therefore, soil contamination with Li could reach the food chain due to its mobility in surface- and ground-waters and uptake into plants. High environmental Li levels adversely affect the health of humans, animals, and plants. Lithium toxicity can be considerably managed through various remediation approaches such as immobilization using clay-like amendments and/or chelate-enhanced phytoremediation. This review integrates fundamental aspects of Li distribution and behaviour in terrestrial and aquatic environments in an effort to efficiently remediate Li-contaminated ecosystems. As research to date has not provided a clear picture of how the increased production and disposal of Li-based products adversely impact human and ecosystem health, there is an urgent need for further studies on this field.

Can Chitin and Chitosan Replace the Lichen Evernia prunastri for Environmental Biomonitoring of Cu and Zn Air Contamination?

This study compared the ability of the lichen Evernia prunastri, chitin and chitosan to take up Cu2+ and Zn2+. It was hypothesized that chitin and chitosan have an accumulation capacity comparable to the lichen, so that these biopolymers could replace the use of E. prunastri for effective biomonitoring of Cu and Zn air pollution. Samples of the lichen E. prunastri, as well as chitin (from shrimps) and chitosan (from crabs), were incubated with Cu and Zn solutions at concentrations of 0 (control), 10, 25, 50, 75, and 100 µM and analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Metal concentrations accumulated by lichen, chitin and chitosan samples were strongly and linearly correlated with the concentrations in the treatment solutions. The lichen always showed significantly higher accumulation values compared to chitin and chitosan, which showed similar accumulation features. The outcomes of this study confirmed the great effectiveness of the lichen Evernia prunastri for environmental biomonitoring and showed that chitin and chitosan have a lower accumulation capacity, thus suggesting that although these biopolymers have the potential for replacing E. prunastri in polluted areas, their suitability may be limited in areas with intermediate or low pollution levels.

Quality means decency-on the quality of teaching through accreditation of the course?

The term "accreditation" applies to the attempts in various fields of scientific work and administration. It refers to an acknowledgement of some particular positive (wanted) property being present in or brought about by either a procedure or technical system, an acknowledgement which is then formally issued by some authority generally accepted to be able to prove and file such statements. Bioindication & Biomonitoring (B&B) technologies are highly influenced by accreditation procedures, because both B&B technologies are often related to accreditation during the overall instrumental measurement processes applied. As an example, tuna fish used for (bio) monitoring salt water systems on pollution by Pb will be presented. Analytical measurement results from the International Measurement Evaluation Programme (IMEP 20) and additionally the construction of the university course "Integrative sustainable management: quality, environmental, health, safety and risk management (QUAR)" are reviewed in this respect. It was a serious finding by the multi-participant IMEP study that neither quality control measures nor accreditation actually ensure improved quality of measurement results, i.e. data produced by analytical laboratories. Accordingly, even though the accreditation of study curricula is often done with utmost diligence and precision, and while it is fairly important for making study curricula throughout Europe (and the World) fitting and comparable to each other to get study results produced and tested at university X also be accepted when changing to university Y, we cannot assume or take for granted that the mere protocol of accreditation will do anything positive to improve the chance to get better or "more correct" results. A single member of lab staff or professor changing to some other position might seriously compromise the turnout of some analytical lab or university course at least in the short term regardless of whether accreditation was done or not. As consequence, data obtained by B&B technologies have to be discussed and handled with the highest care to reach acceptable and scientifically sound goals of quality.

Degradation of atrazine by Frankia alni ACN14a: gene regulation, dealkylation, and dechlorination.

Atrazine is transformed to N-isopropylammelide through hydroxyatrazine as an intermediate as indicated by high-performance liquid chromatography/mass spectroscopy in culture filtrates of Frankia alni ACN14a and Frankia sp. EuI1c. Both Frankia strains have the ability to degrade atrazine via dechlorination and dealkylation and, subsequently, may be using it as a nitrogen and carbon source as detected here by increasing their growth patterns. Bioinformatic analysis of the Frankia genomes revealed that a potential gene cluster involved in atrazine decomposition contains three genes, namely, trzN (FRAAL1474 and FraEuI1c_5874), atzB (FRAAL1473 and FraEuI1c_5875), and atzR (FRAAL1471). The relative messenger RNA gene expression of the former genes was examined by qRT-PCR. The LysR-type transcriptional regulator atzR (FRAAL1471), which is expected to control the cluster expression, showed a 13-fold increase in the expression level under atrazine stress. Moreover, the putative adenosine aminohydrolase 3 atzB (FRAAL1473), which is expected to dealkylate the N-ethyl group of atrazine, showed also an increased expression by factor 16 with increased exposure. Eventually, the trzN (FRAAL1474) gene, which is predicted to encode a putative amidohydrolase catalyzing atrazine dechlorination, exhibited 31-fold increased expression. To our best knowledge, this is the first report about adenosine aminohydrolase 3 function in the dealkylation of the N-ethyl group from atrazine.

Estimating and predicting chemical potentials, distributions, speciation modes and mobilities of radiometals in soil, water and biomass.

Using a method from coordination chemistry, which is linked to ligand field theory, the interaction of (binding of) metal ions with biomass is described and put to quantitative scales including bioconcentration factors for a given living being. This can be extended to radionuclides and biological exposure to them. Fractionation of radionuclides from fission in biomass is discussed in examples from various taxonomic groups, also touching issues of possible human exposure.

Metals in biomass: from the biological system of elements to reasons of fractionation and element use.

BACKGROUND, AIM AND SCOPE: Metal ions generally share the ability/ tendency of interacting with biological material by forming complexes, except possibly for the heavy alkali metals K, Rb and Cs. This is unrelated to the metals being either essential for sustaining life and its reproduction, apparently insignificant for biology, although perhaps undergoing bioconcentration or even being outright toxic, even at low admission levels. Yet, those different kinds of metal-biomass interactions should in some way depend on properties describing coordination chemistries of these very metals. Nevertheless, both ubiquitously essential metals and others sometimes used in biology should share these properties in numeric terms, since it can be anticipated that they will be distinguished from non-essential and/or toxic ones. These features noted above include bioconcentration, the involvement of metal ions such as Zn, Mg, Cu, Fe, etc. in biocatalysis as crucial components of metalloenzymes and the introduction of a certain set of essential metals common to (almost) all living beings (K, Mg, Mo, Mn, Fe, Cu and Zn), which occurred probably very early in biological evolution by 'natural selection of the chemical elements' (more exactly speaking, of the metallomes). MATERIALS AND METHODS: The approach is semiempirical and consists of three consecutive steps: 1) derivation of a regression equation which links complex stability data of different complexes containing the same metal ion to electrochemical data pertinent to the (replaced) ligands, thus describing properties of metal ions in complexes, 2) a graphical representation of the properties--two typical numbers c and x for each metal ion--in some map across the c/x-space, which additionally contains information about biological functions of these metal ions, i.e. whether they are essential in general (e.g. Mg, Mn, Zn) or, for a few organisms of various kinds (e.g. Cd, V), not essential (e.g. rare earth element ions) or even generally highly toxic (Hg, U). It is hypothesized that, if coordination properties of metals control their biological 'feasibility' in some way, this should show up in the mappings (one each for mono and bidentate-bonding ligands). 3) eventually, the regression equation produced in step 1) is inverted to calculate complex stabilities pertinent to biological systems: 3a) complex stabilities are mapped for ligands delivered to soil (-water) by green plants (e.g. citrate, malate) and fungi and, compared to their unlike selectivities and demands of metal use (photosynthesis taking place or not), 3b) the evolution of the metallome during late chemical evolution is reconstructed. RESULTS: These maps show some 'window of essentiality', a small, contrived range/area of c and x parameters in which essential metal ions gather almost exclusively. c and x thus control the possibility of a metal ion becoming essential by their influencing details of metal-substrate or (in cases of catalytic activities) metal-product interactions. Exceptions are not known to be involved in biocatalysis anyhow. DISCUSSION: Effects of ligands secreted, e.g. from tree roots or agaric mycelia to the soil on the respective modes (selectivities) of metal bioconcentration can be calculated by the equation giving complex stability constants, with obvious ramifications for a thorough, systematic interpretation of biomonitoring data. Eventually, alterations of C, N and P-compounds during chemical evolution are investigated--which converted CH4 or CO2, N2 and other non-ligands to amino acids, etc., for example, with the latter behaving as efficient chelating ligands: Did they cause metal ions to accumulate in what was going to become biological matter and was there a selectivity, a positive bias in favour of now-essential metals (see above) in this process? Though there was no complete selectivity of this kind, neither a RNA world in which early ribozymes effected most of biocatalysis, nor a paleoatmosphere containing substantial amounts of CO could have paved the way to the present biochemistry and metallomes. CONCLUSIONS: This way of reasoning provides a causal account for abundance distributions described earlier in the Biological System of Elements (BSE; Markert 1994, Fränzle & Markert 2000, 2002). There is a pronounced change from chemical evolution, where but few transformations depended on metal ion catalysis to biology. RECOMMENDATIONS AND PERSPECTIVES: The application of this numerical approach can be used for modified, weighted evaluation of biomonitoring analytical data, likewise for the prediction of bioconcentration hazards due to a manifold of metal ions, including organometallic ones. This is relevant in ecotoxicology and biomonitoring. In combining apoproteins or peptides synthesized from scratch for purposes of catalysing certain transformations, the map and numerical approaches might prove useful for the selection of central ions which are even more efficient than the 'natural' ones, like for Co2+ in many Zn enzymes.

Nitrogen and metals in two regions in Central Europe: significant differences in accumulation in mosses due to land use?

The study was conducted to test the hypothesis that the regional variability of nitrogen (N) and metal accumulations in terrestrial ecosystems are due to historical and recent ways of landuse. To this end, two regions of Central Europe were selected for investigation: the Weser-Ems Region (WER) and the Euro Region Nissa (ERN). They were assumed to have land use-specific accumulation profiles. Thus, the metal and N accumulations in both regions were examined by means of geostatistically based comparative moss analysis. The sampling and chemical analysis of mosses were conducted in accordance with the convenient guidelines and methods, respectively. The spatial representativity of the sampling sites was computed by means of a land classification which was calculated for Europe by means of classification trees and GIS-techniques. The differences of deposition loads were tested for statistical significance with regard to time and space. The measurement values corroborated the decline of metal accumulation observed since the beginning of the European Metals in Mosses Surveys in 1990. The metal loads of the mosses in the ERN exceeded those in the WER significantly. The opposite holds true for the N concentrations: those in the WER were significantly higher than those in the ERN. The reduction of emissions from power plants, factories and houses was strongly correlated with the decline of deposition and bioaccumulation of metals. As proved by the European Metals in Mosses Surveys, this tendency is due to successful environmental policies. But no such success could be verified by monitoring the accumulation of N in mosses.

Dynamics of trace metals in organisms and ecosystems: prediction of metal bioconcentration in different organisms and estimation of exposure risks.

Metal ions interact with biological materials and their decomposition products by ligation (coordination complex-formation with certain moieties containing O, N, S, etc.). The extent of this interaction depends on the identities of both ligand and metal ion and can be described by some equation derived from perturbation theory. Uptake of metal ions - including highly toxic ones - from soils is controlled by a competition between root exudate components and soil organic matter (SOM) for the ions. SOM consists of a variety of potential ligands which evolve during humification towards more efficient binding (retention) of metals such as Cu, Ni, Cr but also of toxicants like U, Cd. The actual way of interaction can be inferred from stoichiometry of the involved compounds and the C/N ratio in the soil, providing predictions as to which metals will be most efficiently shuttled into green plants or fungi, respectively. The latter, selective process is crucial for closing nutrient cycles and sensitively depends on C/N ratio and the extent of "forcing" by onfalling leaf or needle litter. Therefore, analytical data on the soil can be used to predict possible risks of exposition to toxic metals also for human consumption of plant parts.

Carcinogenesis and chemotherapy viewed from the perspective of stoichiometric network analysis (SNA): what can the biological system of the elements contribute to an understanding of tumour induction by elemental chemical noxae (e.g., Ni2+ , Cd2+ ) and to an understanding of chemotherapy?

The biological application of stoichiometric network analysis (SNA) permits an understanding of tumour induction, carcinogenesis, and chemotherapy. Starting from the Biological System of the Elements, which provides a comprehensive treatment of the functions and distributions of chemical (trace) elements in biology, an attempt is made to interrelate the essential feature of biology and--regrettably--of tumour genesis by superimposing SNA reasoning on common features of all crucial biological processes. For this purpose, aspects, effects and drawbacks of autocatalysis (identical reproduction which can occur either under control or without control [in tumours]) are linked with the known facts about element distributions in living beings and about interference of metals with tumours (in terms of both chemotherapy and carcinogenesis). The essential role of autocatalysis in biology and the drawbacks of either controlled or spontaneous cell division can be used to understand crucial aspects of carcinogenesis and chemotherapy because SNA describes and predicts effects of autocatalysis, including phase effects that may be due to some kind of intervention. The SNA-based classifications of autocatalytic networks in cell biology are outlined here to identify new approaches to chemotherapy.

The Biological System of the Elements (BSE)--a brief introduction into historical and applied aspects with special reference on "ecotoxicological identity cards" for different element species (e.g. As and Sn).

There are different methods to estimate and predict effects of chemical elements and corresponding speciation forms in biochemistry and toxicology, including statements on essentiality and antagonisms. Two approaches are given here: (1) "identity cards" describing biologically fundamental aspects of element chemistry and (2) qualitative discussions which assume the existence of (indirect ways into) chemical autocatalysis to be essential for maintaining life and permitting reproduction. The latter method, developed by the present authors, draws upon Stoichiometric Network Analysis, a safe procedure for complexity reduction in feedback networks) and provides estimates of concentration regimes for different elements suitable for survival and reproduction. The biochemical hierarchy level considered here is that of (metallo-)proteins. Thermodynamic toxicity aspects are given in correlations with DMSO solvent affinities and thiocyanate bonding modes. Effects of antagonists and of ion substitution within metalloenzymes or of metabolic simplification can be dealt with, likewise increased sensitivities within symbiotic relationships and within carcinomas are explained which are relevant for environmental monitoring and tumour therapy, respectively.