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Biomarkers as tools for monitoring within the Water Framework Directive context: concept, opinions and advancement of expertise
2019
Milinkovitch, Thomas | Geffard, Olivier | Geffard, Alain | Mouneyrac, Catherine | Chaumot, Arnaud | Xuereb, Benoit | Fisson, Cedric | Minier, Christophe | Auffret, Michel | Perceval, Olivier | Egea, Emilie | Sanchez, Wilfried
The Water Framework Directive (WFD) currently supports chemical and ecological monitoring programmes in order to achieve the good water surface status. Although chemical and ecological assessments are necessary, they have some limitations. Chemical approaches focus on certain substances identified as priorities, but they do not take into account other potentially harmful substances and also ignore the hazards related to contaminant cocktails. On the other hand, while ecological approaches provide holistic information on the impairment of biological communities in ecosystems, they do not distinguish the role of contaminants in these alterations, and consequently do not allow the establishment of contaminant impact reduction plans. Consequently, ecotoxicologists suggest the use of effect-based tools such as biomarkers. Biomarkers highlight the effect of potentially harmful substances (or a cocktail), and their specificity towards the chemicals makes it possible to properly discriminate the role of toxicants within biological community impairments. Thus, the integration of such tools (besides existing chemical and ecological tools) in the WFD could considerably improve its biomonitoring strategy. The B n' B project (Biomarkers and Biodiversity) exposes key objectives that will allow to (i) establish an inventory of the biomarkers developed by French laboratories; (ii) determine their methodological advancement and limits and, on this basis, formulate recommendations for biomonitoring use and future research needs; (iii) discuss the biomarkers' ecological significance, specificity to contaminants and interpretation capacity; (iv) establish, in fine, a selection of valuable biomarkers to enter the WFD; and (iv) propose integrative tools to facilitate the decision-taking by stakeholders.
Afficher plus [+] Moins [-]Estimating particulate matter (PM) concentrations from a meteorological index for data-scarce regions: A pilot study
2019
de Lange, Anzel | Garland, Rebecca M. | Dyson, Liesl L.
In regions where air quality data are scarce or access thereto is limited, a comprehensive understanding of air pollution is hindered by a lack of emission data and ambient air pollution measurements. Therefore, in this pilot study, we assess the feasibility of estimating particulate matter (PM) mass concentrations from a meteorological index. Measured PM concentrations from air quality monitoring stations (2013–2016) situated in and around South African air pollution priority areas were analysed. Simulated meteorological parameters were used to calculate the newly-developed Air Dispersion Potential (ADP) index, which describes the meteorological potential for pollution dispersion in the atmosphere. For most conditions, there exists weak (r = 0.1–0.29) to moderate (r = 0.30–0.49) correlations between the ADP index and PM classes. At the three stations with adequate data availability, it was found that the ADP index was relatively successful in predicting conditions of high PM concentrations. An investigation of the effect of meteorological conditions on the diurnal variation of PM concentrations led to both the quantification of this effect, and the realization that at these diverse sites, up to 29% of variation in hourly PM concentrations can be explained by variations in meteorology. The application of the index in this way can play an important role in air quality management by quantifying the impacts of meteorological drivers on PM peaks.
Afficher plus [+] Moins [-]Decision support tool to improve the spatial distribution of air quality monitoring sites
2019
Castro, Marlene | Pires, José C.M.
The air quality is an increasingly concerning topic. Efficient air quality monitoring system is highly required in urban areas due to the existing different types of air pollution sources. Consequently, air pollution profiles of the monitored region should be regularly evaluated to infer the efficiency of the monitoring system. This study applied principal components analysis (PCA) to air quality data from Porto (Portugal), aiming to characterize the spatial distribution of NO₂, O₃ and PM₁₀ concentration profiles. In the analysed period (2006 and 2013), some of the selected monitoring sites have been closed and others were moved to other locations. PCA allowed the evaluation of these changes in geographical distribution of the monitoring sites and the definition of proposals to improve the efficiency of air quality monitoring system. The performed analysis concluded that these last changes were correctly performed, but the reduction of the monitoring sites for NO₂ and O₃is still possible, being optimized the current number for PM₁₀. In addition, the application of computational model HYSPLIT (Hybrid Single-Particle Lagrangian Integrated Trajectory) allowed analysing the air pollution transport over long distances in high pollutant concentration episodes, having found that the variation of NO₂ and O₃ concentrations may be strongly influenced by air masses from the north of Spain. For PM₁₀, there are two different air mass trajectories: the transport of air masses from the Galicia region and from North Africa.
Afficher plus [+] Moins [-]Polycyclic aromatic hydrocarbons in two polluted lagoons, eastern coast of the Red Sea: Levels, probable sources, dry deposition fluxes and air-water exchange
2019
Rasiq, K.T. | El-Maradny, Amr | Orif, Mohammed | Bashir, Mohammed Elamin | Turki, Adnan J.
The air-water exchange of polycyclic aromatic hydrocarbons (PAHs) is an important process in determining the fate, transport and chemical loadings of these contaminants in the atmosphere and water bodies. Concentration levels of PAHs in air (gaseous and particulate) and surface water were investigated in the environments of two polluted lagoons along the eastern coast of the Red Sea to study air water exchange and dry deposition fluxes. Nine priority parent PAHs and nine methylated PAHs were identified and quantified by GC-MS. The range of total PAHs in surface water was from 120.29 ng L⁻¹ to 524.45 ng L⁻¹ (average: 308.7 ng L⁻¹, n = 19). The PAHs levels in air recorded significant rise form the previous study. The probable sources of dissolved PAHs in water were found predominantly to be of petrogenic origin in one lagoon and of pyrogenic origin in the other lagoon. The dry deposition fluxes for individual congeners ranged between 0.01 ng m⁻²d⁻¹ to 2.82 μg m⁻²d⁻¹. After Henry's law constant corrections for temperature and salinity; the air-water exchange fluxes were found in the range of −9.7 × 10⁴ to 8.6 × 10⁶ ngm⁻²d⁻¹ with an average of 6.8 × 10⁵ ngm⁻²d⁻¹. Beside the other sources of PAHs in the studied lagoons, high temperature and wastewater dumping might affect the magnitude and direction of air-water exchange fluxes.
Afficher plus [+] Moins [-]Characterisation of ambient Total Gaseous Mercury concentrations over the South African Highveld
2019
Belelie, M.D. | Piketh, S.J. | Burger, R.P. | Venter, A.D. | Naidoo, M.
Mercury is considered a ubiquitous, toxic, and global pollutant. In this study, ambient Total Gaseous Mercury (TGM) concentrations over the South African Highveld are characterised. Studies on ambient mercury in this region is important because of various anthropogenic emission sources. In this pilot study, concentrations of TGM and criteria pollutants (O3, SO2, NO, NO2, and CO) were measured concurrently with meteorological parameters at Balfour (BF), Middelburg (MB), and Standerton (ST) from January 2009 to December 2009. The spatial variation of TGM concentrations ranged from 0.40 to 28.72 ng/m3 (1.99 0.94 ng/m3), 0.12–9.91 ng/m3 (1.04 0.62 ng/m3), and 0.21–32.10 ng/m3 (1.25 1.38 ng/m3), at BF, MB, and ST, respectively. Generally, concentrations fell within the Northern Hemisphere background range of 1.5–1.7 ng/m3 and Cape Point, South Africa background of 1.2–1.4 ng/m3, with the exception of outliers. The outliers were much higher than the background values and may be the result of pollution events. Seasonal variation varied with descending orders of summer, spring, winter, autumn, at BF; summer, winter, autumn, spring at MB; and winter, spring, summer at ST (no data available for autumn). This study observed no profound diurnal patterns at BF and MB where sparse local and regional sources appear to have been the predominant sources. An interesting phenomena, however, was observed at ST where the diurnal cycle suggests a potential significant influence from local domestic combustion sources.
Afficher plus [+] Moins [-]VOCs emission characteristics in motorcycle exhaust with different emission control devices
2019
Dhital, Narayan Babu | Yang, Hsi-Hsien | Wang, Lin-Chi | Hsu, Ya-Tin | Zhang, Han-Yu | Young, Li-Hao | Lu, Jau-Huai
Speciated VOCs and regulated air pollutant emissions (CO, HC and NO) of carburetor (CB) and fuel injection (FI) motorcycles were evaluated based on engine dynamometer tests. Effects of engine loads and emission control systems were evaluated. CB was equipped with oxidation catalytic converter (OCC) and secondary air system (SAS) while FI had three-way catalytic converter (TWC) and oxygen sensor (OS). Under normal operation of the control devices, the emissions of regulated pollutants and the sum of detected VOCs (ΣVOC) were higher in CB than in FI motorcycle. Alkanes and aromatics had the highest concentrations contributing approximately 90% to the ΣVOC while xylene and toluene were most abundant among the BTEX, in both motorcycles. Emissions of all regulated pollutants and ΣVOC increased with increase in engine load. The emission control devices showed differential efficiencies on different VOC groups. Average emission reduction efficiencies of OCC with SAS (CB motorcycle) were 45.4% (ΣVOC) and 48.6% (BTEX) and TWC with OS (FI motorcycle) were 74.4% (ΣVOC) and 88.0% (BTEX). Without SAS, the efficiency of OCC dropped to 30.2% (ΣVOC) and 34.9% (BTEX) in CB motorcycle. Similarly, the efficiency of TWC reduced to 69.0% (ΣVOC) and 85.2% (BTEX) when the OS was blocked in FI motorcycle. The ozone formation potentials of VOCs ranged from 500 mg-O3/m3 (FI motorcycle with TWC and OS, TO 20%) to 2218 mg-O3/m3 (CB motorcycle without control system, TO 30%).
Afficher plus [+] Moins [-]Comparison of the epiphyte Tillandsia bergeri and the XAD-resin based passive air sampler for monitoring airborne pesticides
2019
Silva-Barni, María Florencia | González, Mariana | Miglioranza, Karina Silvia Beatriz
The aim of this study was to assess if the epiphyte Tillandsia bergeri is feasible to be used as a biomonitor of pesticides in the air by comparing with the results of the artificial XAD-resin based passive air sampler (XAD-PAS). Biomonitors and XAD-PAS were deployed at 10 sites of Quequén Grande River watershed (Buenos Aires province, Argentina) during three exposure periods. Endosulfan was the main pesticide found in T. bergeri as well as in XAD-PAS, even after the ban was in effect. Higher endosulfan levels were observed during pesticide application period in XAD-PAS, while T. bergeri showed a decreasing trend during this period. Chlorpyrifos concentrations were in the same order than endosulfan in XAD-PAS, while T. bergeri showed significantly lower levels. Concentrations of legacy pesticides (hexachlorocyclohexanes, chlordanes, dieldrin, heptachlors) registered a low contribution to total pesticides analyzed both in T. bergeri and XAD-PAS, reflecting the past use of organochlorine pesticides in the region. Trifluralin showed the lowest concentrations in T. bergeri while XAD-PAS exhibited a higher proportion in some sites. Even both samplers showed that endosulfan was the most frequent pesticide found, environmental processes such as volatilization and photodegradation, as well as biological processes in T. bergeri have probably occurred and therefore pesticides accumulation was altered. Results demonstrate the importance of taking into account the type of sampling media when analyzing atmospheric pesticide composition. Nevertheless, the use of T. bergeri and XAD-PAS allowed discriminating efficiently the relative contribution of currently used pesticides versus legacy pesticides to air pollution.
Afficher plus [+] Moins [-]LCA-based comparison of two organic fraction municipal solid waste collection systems in historical centres in Spain
2019
Laso Cortabitarte, Jara | García Herrero, María Isabel | Margallo Blanco, María | Bala Gala, Alba | Fullana i Palmer, Pere | Irabien Gulías, José Ángel | Aldaco García, Rubén | Universidad de Cantabria
Municipal solid waste (MSW) collection is an important issue in the development and management of smart cities, having a significant influence on environmental sustainability. Door-to-door and pneumatic collection are two systems that represent a way of arranging waste collection in city´s historic areas in Spain where conventional street-side container collection is not feasible. Since door-to-door collection generates significant direct greenhouse gas emissions from trucks, pneumatic collection emerges as an alternative to the trucking system. While this technology apparently reduces local direct air emissions, it suffers from a large energy demand derived from vacuum production for waste suction. The introduction of new normative frameworks regarding the selective collection of the biodegradable fraction makes necessary a comprehensive analysis to assess the influence of this fraction collection and its subsequent recycling by anaerobic digestion. As a novelty, this work compares both conventional door-to-door and pneumatic collection systems from a life cycle approach focusing on the biodegradable waste. Results indicate that, in spite of the fact electricity production and consumption have a significant influence on the results, the energy savings from the recycling of the organic fraction are higher than the energy requirements. Therefore, the pneumatic collection could be an environmentally-friendly option for MSW management under a circular economy approach in Spanish city´s historic areas, since wastes could be a material or energy source opportunity. | This work has been made under the financial support of the Project Ceres-Procom: Food production and consumption strategies for climate change mitigation (CTM2016-76176-C2-1-R) (AEI/FEDER, UE) financed by the Ministry of Economy and Competitiveness of the Government of Spain.
Afficher plus [+] Moins [-]Recycling, reuse, and circular economy: a challenge for ecotoxicological research
2019
Slaveykova, Vera I. | Couture, Patrice | Duquesne, Sabine | D’hugues, Patrick | Sánchez, Wilfried
Product vs corporate carbon footprint: A case study for the spirit drinks sectors
2019
Leivas Montero, Rubén | Laso Cortabitarte, Jara | Hoehn Capracci, Daniel | Margallo Blanco, María | Fullana i Palmer, Pere | Aldaco García, Rubén | Universidad de Cantabria
The use of Life Cycle Assessment (LCA) has become a common mechanism to evaluate and report the environmental performance of services and products due to its holistic approach and for its standardised method which guaranteeing reproducibility. There is a huge ongoing effort to improve and promote the use of LCA in Europe, by means of the Single Market of Green Products Initiative, which promotes the use of the Product Environmental Footprint (PEF) and the Organisation Environmental Footprint (OEF). Although LCA has been applied in a great variety of industries, there is an even higher worldwide trend of simplification focussing on a single indicator, carbon footprint (CF), relevant to global warming, which is internationally considered as a critical environmental concern. The scope of the CF assessment could be corporate (when all production processes of a company are evaluated) or product (when one of the products is evaluated throughout its life cycle). However, sometimes product CF studies collect corporate data, since for most companies it is easier to report global annual consumptions and emissions instead of the product's specific inputs and outputs. In this framework, this study aims to apply and compare the product and corporate CF methodologies to the case study of the spirit drinks sector in Cantabria (Northern Spain). In particular, to a SME dedicated to the artisanal elaboration of premium spirit drinks such as gin and vodka. The value obtained of the Product Carbon Footprint (PCF) was 0.57 kg CO2 eq. for a bottle (70 cl) of classic gin whereas the Corporate Carbon Footprint (CCF) presented a value of 4.58×103 kg CO2 eq. for Scope 2 and 5.58×104 kg CO2 eq. for Scope 3 in the year 2017. The results indicated that significant environmental impacts were caused during the production of the glass bottle as well as the production of the electricity required in the beverage company.
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