Evaluation of the methyl ester O-methyl acetate derivative of muramic acid for the determination of peptidoglycan in environmental samples by ion-trap GC-MS-MS

Muramic acid (MA) is a unique amino sugar that is a constituent of the peptidoglycan (PG) present in prokaryotic cell walls. MA can serve as a marker for quantifying bacterial load, e.g. in indoor environments, by using gas chromatography-tandem mass spectrometry (GC-MS-MS). We demonstrated recently that the methyl ester O-methyl acetate (MMA) derivative can be used to detect MA in house dust by ion-trap GC-MS-MS. However, since the MMA derivative is not formed from free MA quantification was not optimal. Here we report 1) significant improvements in sample preparation of the MMA derivative and 2) an evaluation of the performance of derivative, using for comparison the alditol acetate derivative, the gold standard in quantitative trace analysis of MA in complex matrices. The MMA derivative was analysed using an MS instrument with internal ionization and the alditol acetate derivative was analysed using an instrument with external ionization. 13C-labelled cyanobacteria, containing MA in their PG, were used as the internal standard. A linear relationship was found between the two methods in studies on 27 parallel samples of airborne dust from school classes collected on filters. Although the analytical sensitivity of the MMA derivatives was somewhat slightly lower than of the alditol acetate derivative, this may be due to differences in yield of derivative, sample clean-up efficiency, or different performance of the GC columns or MS instruments. However preparation of the MMA derivative is quick and compatible with preparation of methyl esters of 3-hydroxy fatty acids (used as markers of Gram negative endotoxin) allowing the levels of both markers to be determined in the same dust sample. In conclusion, the MMA procedure can be used to determine MA in environmental samples with good reproducibility provided the concentration of the 13C-labelled MA internal standard in the cyanobacteria is first determined with an alternative method.     

Design of an integrated monitoring programme in Sweden

A National Swedish Environmental Monitoring Programme, the PMK, has been designed for regular and permanent recording of environmental conditions and long-term changes in background regions, and for keeping track of the flux of pollutants in and between various media. Many of the projects involved deal with integrated monitoring of terrestrial and limnic ecosystems. This work is carried out in or near some 20 small watersheds, usually selected in national parks or nature reserves. The environmental factors monitored in these areas include concentrations of chemical substances in precipitation, soil, groundwater, surface water, and organisms, as well as biological parameters—such as the population size and reproductive capacity of certain species—that may indicate effects of environmental disturbances. The data from this programme can be used as a reference to environmental data acquired near pollution sources, and as a basis for measures against e.g. acid rain, heavy-metal pollution, and use of pesticides. The biological parameters may also reveal effects of yet unknown pollutants or other disturbances.     

Dealing with uncertainty: a case study of controlling insect populations in natural ecosystems

This paper analyses the political process for handling an outbreak of an insect causing human allergic reactions. In the southern part of the Swedish island Gotland in the Baltic Sea, an outbreak of the northern pine processionary moth, Thaumetopoea pinivora, has occurred. With regard to the human nuisance and long-term effects on the tourist industry, demands have been raised for intervention to reduce and control the insect population. At the same time, there have been warnings against treating the insect population because there are knowledge gaps concerning the wider ecological consequences, including effects on biodiversity. This paper analyses the political process and its problem-solving efforts. Of particular interest is how it dealt with the issue of uncertainty. It was found that the uncertainty associated with the issue hindered the development of a shared understanding of the problem and a possible solution. There seems to be a growing need in society to develop the institutional capacity to handle complex issues that cross different sectors, regulatory frameworks and policy targets.     

Comprehensive Study Regarding Greenhouse Gas Emission from Iron Ore Based Production at the Integrated Steel Plant SSAB Tunnplåt AB

During the years 2001–2002, a comprehensive study regarding CO₂ emissions related to the steel production for the integrated steel making production route, was carried out. The study was financed by SSAB and carried out by a research group with members from SSAB, MEFOS and LTU. The aim was to study the emissions from the existing system and how these could be influenced by process changes and by process modifications. The calculations were made using a global spreadsheet model for calculating the CO₂ emissions, developed from an existing Energy and Process Integration model of the same system. The calculated cases included the existing BF/BOF route as well as integration of other processes, e.g., an electric arc furnace, DR processes, COREX and a new future smelting reduction process concept (Sidcomet). All new existing alternative ore based process technologies would increase the specific CO₂ emission from the system. A technology transfer to scrap based metallurgy would significantly decrease the emission level, but is not feasible for SSAB, due to the future product mix and the structure of scrap availability. In a 5–20 year perspective, the existing steel making process route with the use of magnetite ore for pellet production has the lowest specific CO₂ emission. In a long-term perspective, 20–50 years, alternative process routes, e.g., based on H₂ and DRI, could be of interest. Studies on such changes are, however, big projects and should be carried out as joint European and/or international efforts.     

Issues and practices in the use of effects data from FREDERICA in the ERICA Integrated Approach

The ERICA Integrated Approach requires that a risk assessment screening dose rate is defined for the risk characterisation within Tiers 1 and 2. At Tier 3, no numerical screening dose rate is used, and the risk characterisation is driven by methods that can evaluate the possible effects of ionising radiation on reproduction, mortality and morbidity. Species sensitivity distribution has been used to derive the ERICA risk assessment predicted no-effect dose rate (PNEDR). The method used was based on the mathematical processing of data from FRED (FASSET radiation effects database merged with the EPIC database to form FREDERICA) and resulted in a PNEDR of 10 microGy/h. This rate was assumed to ascribe sufficient protection of all ecosystems from detrimental effects on structure and function under chronic exposure. The value was weighed against a number of points of comparison: (i) PNEDR values obtained by application of the safety factor method, (ii) background levels, (iii) dose rates triggering effects on radioactively contaminated sites and (iv) former guidelines from literature reviews. In Tier 3, the effects analysis must be driven by the problem formulation and is thus highly case specific. Instead of specific recommendations on numeric values, guidance on the sorts of methods that may be applied for refined effect analysis is provided and illustrated.