Green additives to enhance silica dissolution during water treatment

The effect of various environmentally friendly chemical additives on the dissolution of colloidal silica is systematically studied. These silica scale dissolvers are principally polycarboxylates with one to five –COOH groups, mixed polycarboxylates/phosphonates and aminoacids. Based on these results, an effort is made to link their dissolution performance to structural features in this structure/function study. Presence of additional groups (eg. –PO₃H₂, –NH₂, or –OH) in the dissolver molecule augments the dissolution process.     

Decision support models for solid waste management: Review and game-theoretic approaches

This paper surveys decision support models that are commonly used in the solid waste management area. Most models are mainly developed within three decision support frameworks, which are the life-cycle assessment, the cost–benefit analysis and the multi-criteria decision-making. These frameworks are reviewed and their strengths and weaknesses as well as their critical issues are analyzed, while their possible combinations and extensions are also discussed. Furthermore, the paper presents how cooperative and non-cooperative game-theoretic approaches can be used for the purpose of modeling and analyzing decision-making in situations with multiple stakeholders. Specifically, since a waste management model is sustainable when considering not only environmental and economic but also social aspects, the waste management bargaining game is introduced as a specific decision support framework in which future models can be developed.     

Biomarkers of end of shift exposure to disinfection byproducts in nurses

Increased disinfectant use commonly takes place in hospitals and other health care settings. A cross-sectional study among active nurses in two Cypriot public hospitals (n = 179) was conducted to examine the prevalence of exposure to disinfection byproducts (DBPs), such as trihalomethanes (THMs) using both self-reported information and biomarker measurements. The objectives of this study were to: i) quantify the magnitude and variability of occupational exposure to disinfectants/DBPs in nurses, ii) generate job exposure matrices (JEM) and job task exposure matrices (JTEM) for disinfectants, and iii) assess the major determinants of urinary THMs in nurses. End of shift urinary total THM values showed high variability among the nurses, but did not differ between hospitals. The disinfectant group of alcohols/phenols was used by > 98% of nurses, followed by octenidine (82%), iodine and chlorine (39%, each), chlorhexidine (25%), formaldehyde (12%), hydrogen peroxide (11%), and peracetic acid/ammonia/quaternary ammonium compounds (QACs), all being < 8% each. Chlorine use during the past 24 hr was associated with significantly (p < 0.05) lower brominated THMs (BrTHMs) after adjusting for age, gender and BMI, while a positive association was shown for TCM and the sum of all THMs (TTHMs), albeit not significant. Nurses were exposed to nearly double the levels of TTHMs and BrTHMs (median and IQR, 1027 [560, 2475] ng/g and 323 [212, 497] ng/g, respectively) when compared to those of the general population (552 [309,989] ng/g and 152 [87,261] ng/g, respectively). This was the first occupational health dataset reporting measurements of biomarkers of end of shift exposures to disinfectants/DBPs.     

Model-driven development of covariances for spatiotemporal environmental health assessment

Known conceptual and technical limitations of mainstream environmental health data analysis have directed research to new avenues. The goal is to deal more efficiently with the inherent uncertainty and composite space-time heterogeneity of key attributes, account for multi-sourced knowledge bases (health models, survey data, empirical relationships etc.), and generate more accurate predictions across space-time. Based on a versatile, knowledge synthesis methodological framework, we introduce new space-time covariance functions built by integrating epidemic propagation models and we apply them in the analysis of existing flu datasets. Within the knowledge synthesis framework, the Bayesian maximum entropy theory is our method of choice for the spatiotemporal prediction of the ratio of new infectives (RNI) for a case study of flu in France. The space-time analysis is based on observations during a period of 15 weeks in 1998–1999. We present general features of the proposed covariance functions, and use these functions to explore the composite space-time RNI dependency. We then implement the findings to generate sufficiently detailed and informative maps of the RNI patterns across space and time. The predicted distributions of RNI suggest substantive relationships in accordance with the typical physiographic and climatologic features of the country.     

MOSESS: A New Emission Model for the Compilation of Model-Ready Emission Inventories—Application in a Coal Mining Area in Northern Greece

Over the last years, the capabilities of chemical transport models have been greatly improved and the need for more accurate emission data has increased as well. In the past, a number of emission models have been developed and present different functionalities and applications. The majority of these though cover very specific needs. This paper describes the development of a new emission model namely computer model for the construction of model-ready emission inventories (MOSESS) which is used to compile high-resolution emission inventories or improve existing ones, utilizing complex GIS techniques. The model aims in helping chemical modelers to obtain a better overview of their modeling application by having a comprehensive understanding of the emission input. MOSESS incorporates more than 70 different emission calculation methodologies, and it is capable of handling external emission databases (such as EMEP and EPER) from which emissions can be extracted. The temporal variation (annual/daily and diurnal processing), chemical speciation of NMVOCs and particles, vertical distribution and point source treatment, as well as the spatial disaggregation of emissions (utilizing numerous spatial proxies including high-resolution landuses) can help create model-ready emission inventories which can be used for contemporary modeling applications.     

Improved liquid chromatographic photo diode array mass spectrometric determination of 5-hydroxymethylfurfural and related furfurals in honey

5-Hydroxymethylfurfural is found in several food commodities, including honey. Its concentration is used as one of honey's quality indicators since elevated 5-hydroxymethylfurfural levels indicate overheating and aging of the product. In this context, the European Commission and Codex Alimentarius established the maximum tolerable level for 5-hydroxymethylfurfural, for general type honeys intended for human consumption, at 40 mg kg^?1. In this study, 5-hydroxymethylfurfural, 2-furfural, and the furfuralic derivative 5-methyl-2-furfural were investigated in Greek honey samples, through a high performance liquid chromatographic photo diode array mass spectrometric method developed and validated. Sample preparation was based on a modification of the ‘Quick, Easy, Cheap, Effective, Rugged, and Safe’ procedure. The method was sensitive, exhibiting limit of detection for 5-hydroxymethylfurfural at 0.1 mg kg^?1, far below the permissible level of 40 mg kg^?1. Levels of 5-hydroxymethylfurfural in 28 honey samples varied from 0.5 to 23.5 mg kg^?1, thus, not worrying for consumers. Traces of 2-furfural were detected in limited samples.     

High uptake of 2,4,6-trinitrotoluene by vetiver grass--potential for phytoremediation?

2,4,6-Trinitrotoluene (TNT) is a potent mutagen, and a Group C human carcinogen that has been widely used to produce munitions and explosives. Vast areas that have been previously used as ranges, munition burning, and open detonation sites are heavily contaminated with TNT. Conventional remediation activities in such sites are expensive and damaging to the ecosystem. Phytoremediation offers a cost-effective, environment-friendly solution, utilizing plants to extract TNT from contaminated soil. We investigated the potential use of vetiver grass (Vetiveria zizanioides) to effectively remove TNT from contaminated solutions. Vetiver grass plants were grown in hydroponic systems containing 40 mg TNTL(-1) for 8d. Aqueous concentrations of TNT reached the method detection limit ( approximately 1 microg L(-1)) within the 8-d period, demonstrating high affinity of vetiver for TNT, without any visible toxic effects. Results from this preliminary hydroponic study are encouraging, but in need of verification using TNT-contaminated soils.     

Diversity of cyanobacterial phylotypes in a Mediterranean drinking water reservoir (Marathonas, Greece)

The structure of the cyanobacterial community in a large drinking water reservoir (Marathonas, Greece) was investigated in October 2007 and September 2008. Cyanobacteria-specific primers were used for the PCR amplification of cyanobacterial 16S rDNAs from three water column sites and the water collection tank. In total, 199 clones were sequenced representing 52 unique cyanobacterial, including chloroplast-related, and 11 non-cyanobacterial phylotypes. All cyanobacterial phylotypes belonged to the order Chroococcales. Cluster analysis showed that the cyanobacterial communities in 2007 in the three water column sites showed high similarity between the stations and low diversity (H?=?1.17???1.44), due to the occurring common phylotypes, while all sites in 2008 had very low similarities between them and higher diversity (H?=?1.56???2.40). Some of the most abundant phylotypes were closely related (>98%) to members of the genus Gloeocapsa and a potentially toxin-producing strain of Microcystis aeruginosa. The non-cyanobacterial phylotypes were either unaffiliated or belonged to the Verrucomicrobia, and were related with sequences originating from lake water habitats.     

Assessing non-financial reports according to the Global Reporting Initiative guidelines: evidence from Greece

In recent years a growing number of companies around the world have started reporting on issues other that those in the financial domain, in order to discharge their accountability efforts. While such non-financial accounting and reporting footprints, in terms of relevant policies and practices, are evident among all regions and such activities are becoming a universal trend, the level of uptake and diffusion varies from country to country. This paper contributes to the country-level analyses of non-financial reporting by assessing the quality and inclusiveness of triple-bottom-line reports published by companies operating in Greece. To accomplish this, a numerical scoring system was devised, based on the de facto global standard on corporate non-financial reporting, the Global Reporting Initiative guidelines. Overall findings reveal major gaps in the disclosing practices of Greek organizations and denote that there is much room for improvement in order to meet international standards and promote effective engagement with their stakeholders.