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The preparation of a new candidate certified reference material CRM for trace elements based on the antarctic bivalve Adamussium colbeckiIRMM 813 was carried out by the Istituto Superiore di Sanità ISS, Rome, Italy in cooperation with the Institute for Reference Materials and Measurements, Joint Research Centre of the European Commission EC-JRC-IRMM, in the frame of the Italian National Programme of Research in Antarctica Programma Nazionale di Ricerca in Antartide, PNRA. Samples were collected at Terra Nova Bay Ross Sea during the 2000–2001 expedition in Antarctica. The preparation of a material suitable for certification was performed by the EC-JRC-IRMM. Measurements for homogeneity and short-term stability tests were carried out by ISS. The elements selected for the certification project were As, Cd, Cu, Cr, Fe, Mn, Ni and Zn. For the above-mentioned tests, the determination of the elements of interest was performed on samples mineralised by microwave-assisted acid digestion. The analytical techniques employed to this end were inductively coupled plasma atomic emission spectrometry ICP-AES and inductively coupled plasma dynamic reaction cell quadrupole mass spectrometry ICP-DRC-Q-MS. The candidate material was shown to be fit for purpose with regard to homogeneity and short-term stability, thus allowing the following phases of the certification project to be undertaken, in the first place the selection of expert laboratories for the accomplishment of the certification campaign.

The recovery of trace elements of ecotoxic importance has been studied on certified soil and sediment reference samples after pressurized digestions with HNO3, HNO3+HF and HNO3+HCl+HF mixtures, respectively. The acid digests have been analyzed by ICP-MS. The results indicate that digestion with nitric acid alone is satisfactory for the recovery of As, Cd, Co, Cu and Zn. Cr and Pb showed lower recoveries with HNO3 alone but addition of HF improved their extraction. With appropriate corrections, ICP-MS can be used for the routine analysis of soils and sediments. These digestion procedures, evaluated based on reference samples, have been used for the trace element characterization of soil samples from the German Environmental Specimen Bank.

The crystallization enthalpies of MgCl2 in MgCl2-H2O-cosolvent systems at 25°C were determined calorimetrically as a function of the cosolvent content in the mixed solvent. Methanol, acetone, and N,N-dimethylformamide were employed as cosolvents. The results show the individual cosolvents to have very differently influences on the energy state of the salt in the saturated solution. The most pronounced changes are effected by an increase of the DMF content in the mixed solvent. The intensity of Mg2+-DMF interaction at a higher DMF content in the saturated solution considerably exceeds the Li+-DMF interaction in LiCl solutions.

The crystallization enthalpy of LiCl at 25°C in LiCl-H2O-cosolvent systems is determined calorimetrically as a function of the cosolvent content in the mixed solvent. This parameter is used for the investigation of heat phenomena accompanying the solvation of the salt in a saturated solution. The cosolvents employed include methanol, acetone, and N,N-dimethylformamide. The most pronounced change is effected by replacement of water with N,N-dimethylformamide.

Within the framework of the German Environmental Specimen Bank program, Tl, Cu, Pb, Cd and Zn were determined in homogenized materials from the limnic environment using Isotope Dilution Mass Spectrometry (IDMS) with thermal ionization. The analytical procedures which were developed for the trace metal analysis of bioindicator and sediment samples are described in detail. Results obtained in bream, mussels (Dreissena polymorpha) and sediments of Lake Constance/Estuary of Constance in the sampling years 1981, 1985, 1988, 1990, 1992 and 1993 are discussed and compared with those of bream from the lakeland district of Born-hoeved/Lake Belau and from the River Saar as well as from reference materials.

Analytical investigations of metals within the present program of the German Environmental Specimen Bank (ESB) are briefly introduced. The focus is directed to challenges and opportunities which are provided by an ESB for analytical chemistry. Several aspects of instrumental approaches for environmental analysis, bioindication, speciation, data evaluation and quality assurance are discussed. Illustrative examples of ESB results are presented concerning metal concentrations in biological material, comparison of ecosystems and long-term tendencies.

The aim of the present study was to compare data on 24-h energy expenditure (EE24 h) in nine boys and ten girls (mean age 9.3 and 8.1 years, respectively) by heart rates (fc) combined with energy expenditure obtained from a 1-day stay in an indirect calorimeter (EEcal) and a 2-week period of normal living using the doubly labelled water method (EEdlw). Individual calibration curves were derived fromfc and oxygen uptake measured during sleep (in the calorimeter), standing and walking on a treadmill. An estimation of energy expenditure based on 24-hfc, monitoring (EEfc) was made during the stay in the calorimeter and on a normal school-day. Mean results showed an overestimation in EEfc compared to EEcal and EEdlw of 10.4% and 12.3% respectively, varying from 6.3% to 16.2%. These results confirmed earlier observations in adults that for a group thefc method overestimates EE24 h by about 10%.