Co-leaching of brominated compounds and antimony from bottled water

A fast-growing bottled water market is occasionally challenged by reports calling for contaminant leaching from water-contact materials (plastics). Our focus was on leaching of antimony (Sb) and brominated compounds expressed by total soluble bromine (Br) measurements, including those of polybrominated diphenyl ethers (PBDE). Studies are lacking on concomitant leaching of two or more inorganic plastic constituents from the same bottle. A market-representative basket survey of bottled water was initiated in Boston, USA supermarkets. Bottled water classes sampled were: i) non-carbonated (NCR), ii) carbonated (CR), and iii) non-carbonated and enriched (NCRE). Plastic bottle materials sampled were: polyethylene terephthalate (PET), high-density polyethylene (HDPE), polystyrene (PS), and polycarbonate (PC). Storage conditions for the 31 bottled water samples were: 23 °C temperature, no-shaking and 12 h/12 h light/dark for 60 days of equilibration. Average Br and Sb concentrations after 60-days of storage followed the order of NCR < CR = NCRE, and NCR < CR < NCRE, respectively, suggesting that the presence of dissolved carbon dioxide in CR samples coupled to additions of flavors and color to NCRE could explain the elevated leaching of Br and Sb. Combining all bottled water classes and plastic material types, a highly significant (p < 0.001) correlation was observed between log-transformed soluble Br and Sb concentrations, suggesting similar leaching behavior. Among samples with the highest soluble Br concentrations, BDE-209 congener was qualitatively confirmed in three out of four bottled water samples. The PC, HDPE, and PS samples exhibited significantly (p < 0.05) lower Sb and Br leaching than PET. Upon quantitative validation of PBDE leaching from certain plastic bottles into water, a revisit to existing PBDE exposure assessment reports will be deemed necessary.     

Soil column experiments used as a means to assess transport,sorption, and biodegradation of pesticides in groundwater

Soil column experiments are used to investigate the fate of three pesticides of high, intermediate, and low solubility in groundwater: N- phosphonomethyl glycine (glyphosate); O,O-diethyl-S-[(ethylthio)methyl]phosphorodithioate (phorate); (2,4-dichlorophenoxy)acetic acid (2,4-D). Feed solutions are prepared by adding each pesticide (100 mg/L glyphosate, 50 μ g/L phorate, 50 mg/L 2,4-D) along with conservative tracer, KBr, in synthetic groundwater. The concentration of the pesticides in effluents is detected by ion chromatography (glyphosate, 2,4-D) and GC-FID (phorate). The Br^? breakthrough curves are employed to estimate the dispersion coefficient and mean pore velocity in each column. Solute transport and reactive models accounting for equilibrium/non-equilibrium sorption and biodegradation are coupled with inverse modeling numerical codes to estimate the kinetic parameters for all pesticides.     

The role of materials selection in the urban heat island effect in dry mid-latitude climates

This work investigates the role of materials selected for different urban surfaces (e.g. on building walls, roofs and pavements) in the intensity of the urban heat island (UHI) phenomenon. Three archetypal street-canyon geometries are considered, reflecting two-dimensional canyon arrays with frontal packing densities (λ_f) of 0.5, 0.25 and 0.125 under direct solar radiation and ground heating. The impact of radiative heat transfer in the urban environment is examined for each of the different built packing densities. A number of extreme heat scenarios were modelled in order to mimic conditions often found at low- to mid-latitudes dry climates. The investigation involved a suite of different computational fluid dynamics (CFD) simulations using the Reynolds-Averaged Navier–Stokes equations for mass and momentum coupled with the energy equation as well as using the standard k-ε turbulence model. Results indicate that a higher rate of ventilation within the street canyon is observed in areas with sparser built packing density. However, such higher ventilation rates were not necessarily found to be linked with lower temperatures within the canyon; this is because such sparser geometries are associated with higher heat transfer from the wider surfaces of road material under the condition of direct solar radiation and ground heating. Sparser canyon arrays corresponding to wider asphalt street roads in particular, have been found to yield substantially higher air temperatures. Additional simulations indicated that replacing asphalt road surfaces in streets with concrete roads (of different albedo or emissivity characteristics) can lead up to a ~5 °C reduction in the canyon air temperature in dry climates. It is finally concluded that an optimized selection of materials in the urban infrastructure design can lead to a more effective mitigation of the UHI phenomenon than the optimisation of the built packing density.     

Waste management project's alternatives: A risk-based multi-criteria assessment (RBMCA) approach

This paper examines the evaluation of a waste management project’s alternatives through a quantitative risk analysis. Cost benefit analysis is a widely used method, in which the investments are mainly assessed through the calculation of their evaluation indicators, namely benefit/cost (B/C) ratios, as well as the quantification of their financial, technical, environmental and social risks. Herein, a novel approach in the form of risk-based multi-criteria assessment (RBMCA) is introduced, which can be used by decision makers, in order to select the optimum alternative of a waste management project. Specifically, decision makers use multiple criteria, which are based on the cumulative probability distribution functions of the alternatives’ B/C ratios. The RBMCA system is used for the evaluation of a waste incineration project’s alternatives, where the correlation between the criteria weight values and the decision makers’ risk preferences is analyzed and useful conclusions are discussed.     

Determining the ventilation and aerosol deposition rates from routine indoor-air measurements

Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO₂, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h^?1. The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors’ concentrations were found to be compared well with the experimentally measured values.     

Co-occurrence profiles of trace elements in potable water systems: a case study

Potable water samples (N?=?74) from 19 zip code locations in a region of Greece were profiled for 13 trace elements composition using inductively coupled plasma mass spectrometry. The primary objective was to monitor the drinking water quality, while the primary focus was to find novel associations in trace elements occurrence that may further shed light on common links in their occurrence and fate in the pipe scales and corrosion products observed in urban drinking water distribution systems. Except for arsenic at two locations and in six samples, rest of the analyzed elements was below maximum contaminant levels, for which regulatory values are available. Further, we attempted to hierarchically cluster trace elements based on their covariances resulting in two groups; one with arsenic, antimony, zinc, cadmium, and copper and the second with the rest of the elements. The grouping trends were partially explained by elements’ similar chemical activities in water, underscoring their potential for co-accumulation and co-mobilization phenomena from pipe scales into finished water. Profiling patterns of trace elements in finished water could be indicative of their load on pipe scales and corrosion products, with a corresponding risk of episodic contaminant release. Speculation was made on the role of disinfectants and disinfection byproducts in mobilizing chemically similar trace elements of human health interest from pipe scales to tap water. It is warranted that further studies may eventually prove useful to water regulators from incorporating the acquired knowledge in the drinking water safety plans.     

Linking Hydrogeological and Ecological Tools for an Integrated River Catchment Assessment

Ecological (biological and hydrochemical assessment) and hydrogeological (vulnerability and pollution risk mapping) tools have been combined to assess the ecological quality and hydrogeological vulnerability of an agricultural river basin. In addition, the applicability of the recently developed vulnerability assessment approach (COP method) in the particular environmental conditions was tested by comparing its results with hydroecological assessment tools (i.e., pollution metrics). Five sampling sites were selected and sampled for benthic macroinvertebrates and physicochemical variables during summer and spring. Overall, sites ranged from moderate to poor ecological quality. The results illustrated that 26% of the study area was of moderate pollution risk, while 65% was classified as of low and very low risk zones. However, the higher elevation zones where calcareous rock formations are encountered presented moderate to high pollution risk that was accredited by the ecological quality assessment. Pollution metrics facilitated from hydrochemical analysis indicated a significant association with groundwater vulnerability, thus validating vulnerability and risk estimations. This study indicated that the particular groundwater pollution risk mapping methodology and the water quality assessment indices can be well combined to provide an integrated evaluation tool at a catchment scale.     

Development of an Evaluation Methodology for Triple Bottom Line Reports Using International Standards on Reporting

The purpose of this article is twofold. First, evaluation scoring systems for triple bottom line (TBL) reports to date are examined and potential methodological weaknesses and problems are highlighted. In this context, a new assessment methodology is presented based explicitly on the most widely acknowledged standard on non-financial reporting worldwide, the Global Reporting Initiative (GRI) guidelines. The set of GRI topics and performance indicators was converted into scoring criteria while the generic scoring devise was set from 0 to 4 points. Secondly, the proposed benchmark tool was applied to the TBL reports published by Greek companies. Results reveal major gaps in reporting practices, stressing the need for the further development of internal systems and processes in order to collect essential non-financial performance data. A critical overview of the structure and rationale of the evaluation tool in conjunction with the Greek case study is discussed while recommendations for future research on the field of this relatively new form of reporting are suggested.     

Complaints regarding occupational health and safety in the area of Thessaloniki (Greece)

This paper deals with the complaints regarding occupational health and safety in the area of Thessaloniki (Greece). It seeks to examine who are the complainers and which companies or activities do they complain about, to what extent are complaints relevant to occupational health and safety and whether the complaints result to penalties. Such complaints do not pertain to all economic sectors equally, nor do they derive from all kinds of sources. Furthermore, it appears that complaints “irrelevant” to occupational health and safety are twice as many as the “relevant” ones. In three quarters of the cases, the complaints do not result to any kind of sanction; more specifically, in one fifth of the cases, the complaints are not followed by any action taken by the office in charge. All things considered, it seems that filing complaints does not imply finding the most dangerous workplaces. Therefore, investigation of complaints should not be considered more significant than other inspection activities.