PM sources in a highly industrialised area in the process of implementing PM abatement technology. Quantification and evolution

Principal component analysis (PCA) coupled with a multilinear regression analysis (MLRA) was applied to PM(10) speciation data series (2002-2005) from four sampling sites in a highly industrialised area (ceramic production) in the process of implementing emission abatement technology. Five common factors with similar chemical profiles were identified at all the sites: mineral, regional background (influenced by the industrial estate located on the coast: an oil refinery and a power plant), sea spray, industrial 1 (manufacture and use of glaze components, including frit fusion) and road traffic. The contribution of the regional background differs slightly from site to site. The mineral factor, attributed to the sum of several sources (mainly the ceramic industry, but also with minor contributions from soil resuspension and African dust outbreaks) contributes between 9 and 11 microg m(-3) at all the sites. Source industrial 1 entails an increase in PM(10) levels between 4 and 5 microg m(-3) at the urban sites and 2 microg m(-3) at the suburban background site. However, after 2004, this source contributed less than 2 microg m(-3) at most sites, whereas the remaining sources did not show an upward or downward trend along the study period. This gradual decrease in the contribution of source industrial 1 coincides with the implementation of PM abatement technology in the frit fusion kilns of the area. This relationship enables us to assess the efficiency of the implementation of environmental technologies in terms of their impact on air quality.     

Distribution of polycyclic aromatic hydrocarbons (PAHs) and tributyltin (TBT) in Barcelona harbour sediments and their impact on benthic communities

Sediments have long been recognised as a sink for many contaminants like polycyclic aromatic hydrocarbons (PAHs) and tributyltin (TBT), which by virtue of their nature can strongly adsorb onto sediments affecting the benthic community inhabiting them. Using geographical information systems, this study reports and combines the results of several already existing studies along Barcelona harbour in order to assess the potential ecological impacts of these contaminants on the benthos of the harbour ecosystem. Chemical analysis indicated low to moderate contents of PAHs and high contents of TBT in sediments in Barcelona harbour. Comparison against existing sediment quality guidelines (SQGs) indicated that acutely toxic effects would not be expected for PAHs but for TBT, which represents a serious environmental threat for the benthic community. Benthos surveys revealed a deterioration of the benthic community throughout the harbour, especially in the inner port.     

Thermogravimetric kinetic analysis and pollutant evolution during the pyrolysis and combustion of mobile phone case

The increase in electronic waste, including cellular telephones, worldwide is a worrying reality. For this reason, urgent action on the management of these wastes is necessary within a framework that respects the environment and human health. Mobile phone components can be physically segregated through grinding at the dismantling sites, in order to reuse or reprocess (via chemical or physical recycling) the recovered plastics and valuable metals. A kinetic study of the thermal decomposition of a mobile phone case has been carried out under different conditions by thermogravimetry. Several experiments were performed in a nitrogen atmosphere (pyrolysis runs) and also in an oxidative atmosphere with two different oxygen concentrations (10% and 20% oxygen in nitrogen). Dynamic runs and dynamic+isothermal runs have been carried out to obtain much decomposition data under different operating conditions. Moreover some TG-MS runs were performed in order to better understand the thermal decomposition of a mobile phone case and identify some compounds emitted during the controlled heating of this material. A scheme of two independent reactions for pseudocomponents has been proposed for the pyrolysis process. For the combustion runs, the scheme proposed includes two pyrolytic reactions competing with other two reactions with formation of an intermediate residue, and finally the reaction of oxidation/burning of the intermediate residue. Furthermore, pyrolysis and combustion runs at 500 °C in a horizontal laboratory furnace were carried out. More than 50 compounds, including carbon oxides, light hydrocarbons, and polycyclic aromatic hydrocarbons (PAHs) have been identified and quantified. The main semivolatile compounds detected were phenol and styrene. Furthermore, polychlorodibenzo-p-dioxin and polychlorodibenzofurans (PCDD/Fs) and dioxin-like PCBs produced were analyzed. In the combustion run, PCDDs were obtained in higher amounts than PCDFs and HxCDD was the most emitted homologue.     

Monitoring of heavy metal concentrations in home outdoor air using moss bags

One monitoring station is insufficient to characterize the high spatial variation of traffic-related heavy metals within cities. We tested moss bags (Hylocomium splendens), deployed in a dense network, for the monitoring of metals in outdoor air and characterized metals’ long-term spatial distribution and its determinants in Girona, Spain. Mosses were exposed outside 23 homes for two months; NO₂ was monitored for comparison. Metals were not highly correlated with NO₂ and showed higher spatial variation than NO₂. Regression models explained 61-85% of Cu, Cr, Mo, Pb, Sb, Sn, and Zn and 72% of NO₂ variability. Metals were strongly associated with the number of bus lines in the nearest street. Heavy metals are an alternative traffic-marker to NO₂ given their toxicological relevance, stronger association with local traffic and higher spatial variability. Monitoring heavy metals with mosses is appealing, particularly for long-term exposure assessment, as mosses can remain on site many months without maintenance.     

Indoor metallic pollution related to mining activity in the Bolivian Altiplano

The environmental pollution associated with mining and metallurgical activities reaches its greatest extent in several Andean cities and villages. Many locations in this area have accumulated through centuries a large amount of mining wastes, often disregarding the magnitude of this situation. However, in these naturally mineralized regions, there is little information available stating the exact role of mining and metallurgical industries in urban pollution. In this study, we demonstrated that the various metallic elements present in indoor dust (As, Cd, Cu, Pb, Sb, Sn, Zn) had a common origin and this contamination was increased by the proximity to the mines. Lead dust concentration was found at concerning levels for public health. In addition, wrong behaviors such as carrying mining workwear home contributed to this indoor dust pollution. Consequently, the constant exposure of the population could represent a potential health hazard for vulnerable groups, especially children.     

Thermal decomposition of electronic wastes: mobile phone case and other parts

Pyrolysis and combustion runs at 850°C in a horizontal laboratory furnace were carried out on different parts of a mobile phone (printed circuit board, mobile case and a mixture of both materials). The analyses of the carbon oxides, light hydrocarbons, polycyclic aromatic hydrocarbons (PAHs), polychlorodibenzo-p-dioxin, polychlorodibenzofurans (PCDD/Fs), and dioxin-like PCBs are shown. Regarding semivolatile compounds, phenol, styrene, and its derivatives had the highest yields. In nearly all the runs the same PAHs were identified, naphthalene being the most common component obtained. Combustion of the printed circuit board produced the highest emission factor of PCDD/Fs, possibly due to the high copper content.     

Diastereoisomer- and enantiomer-specific determination of hexabromocyclododecane in fish oil for food and feed

Fish oils are one of the main sources of ω-3 fatty acids. However, they can present elevated levels of some lipophilic pollutants, such as hexabromocyclododecanes (HBCDs). Since data about HBCDs in fish oil samples are very limited, in this study, 25 samples of fish oil for feed and food have been analyzed. Total HBCDs, as well as, α-, β- and γ-diastereoisomers have been determined. Total HBCDs ranged from 0.09 to 26.8 ng g⁻¹, with higher concentrations in fish oil for feed (average value of 9.69 ng g⁻¹) than those for food (1.14 ng g⁻¹). Concentrations of α-HBCD (average value of 4.12 ng g⁻¹ in feed samples and 0.48 ng g⁻¹ in food samples) and γ-HBCD (5.05 and 0.43 ng g⁻¹ respectively) were higher than that of β-HBCD (0.52 and 0.19 ng g⁻¹ respectively) in most of the samples. However, none of them was predominant in the samples. Concentrations of HBCDs were compared to concentrations of other pollutants and correlation between dioxin and dioxin-like PCBs levels and HBCDs levels were observed. Intake of HBCDs was calculated for fish oil with human consumption purposes and it ranged from 0.08 to 5.38 ng HBCDs d⁻¹, which could contribute significantly to HBCDs total intake. Enantiomeric fractions were also determined. No clear enrichment was observed for γ-HBCD, while (−)-α-HBCD enrichment was detected in some samples.     

Interactive effects of metal contamination and pathogenic organisms on the introduced marine bivalve Ruditapes philippinarum in European populations

In natural environment, marine organisms are concomitantly exposed to pollutants and multiple disease agents resulting in detrimental interactions. The present study evaluated interactive effects of metal contamination (cadmium) and pathogenic organisms (trematode parasites Himasthla elongata and pathogenic bacteria Vibrio tapetis) singularly and in combination on the bivalve Ruditapes philippinarum, an introduced species to Europe, under laboratory controlled conditions. After 7 days, metal bioaccumulation and pathogen load were analyzed as well as metallothionein (MT) response and hemocyte concentrations and activities. Results showed that infection by opportunistic pathogens affects metal accumulation, leading to maximal Cd accumulation in co-infected clams. Among stressors only V. tapetis induced significant effects on immune parameters whereas a particular interaction “trematode-bacteria” was shown on MT responses. Despite low trematode infection in agreement with the resistant status of R. philippinarum to these macroparasites, significant interaction with bacteria and metal occurred. Such results highlight the necessity of taking pathogens into account in ecotoxicological studies.     

Fungal biofilters for toluene biofiltration: evaluation of the performance with four packing materials under different operating conditions

Packing materials play a key role in the performance of bioreactors for waste gas treatment and particularly in biofilter applications. In this work, the performance of four differently packed biofilters operated in parallel for the treatment of relatively high inlet concentration of toluene was studied. The reactors were compared for determining the suitability of coconut fiber, digested sludge compost from a waste water treatment plant, peat and pine leaves as packing materials for biofiltration of toluene. A deep characterisation of materials was carried out. Biological activity and packing capabilities related to toluene removal were determined throughout 240 days of operation under different conditions of nutrients addition and watering regime. Also, biofilters recovering after a short shutdown was investigated. Nutrient addition resulted in improved removal efficiencies (RE) and elimination capacities (EC) of biofilters reaching maximum ECs between 75 and 95 g m(-3)h(-1) of toluene. In the first 80 days, the pH decreased progressively within the reactors, causing a population change from bacteria to fungi, which were the predominant decontaminant microorganisms thereafter. All reactors were found to recover the RE rapidly after a 5 days shutdown and, in a maximum of 7 days, all reactors had been completely recuperated. These results point out that fungal biofilters are a suitable choice to treat high loads of toluene. In general, coconut fiber and compost biofilters exhibited a better performance in terms of elimination capacity and long-term stability.     

Arsenic speciation of atmospheric particulate matter (PM10) in an industrialised urban site in southwestern Spain

An arsenic speciation study has been performed in PM10 samples collected on a fortnight basis in the city of Huelva (SW Spain) during 2001 and 2002. The arsenic species were extracted from the PM10 filters using a NH2OH x HCl solution and sonication, and determined by HPLC-HG-AFS. The mean bulk As concentration of the samples analyzed during 2001 and 2002 slightly exceed the mean annual 6 ng m(-3) target value proposed by the European Commission for 2013, arsenate [As(V)] being responsible for the high level of arsenic. The speciation analyses showed that As(V) was the main arsenic species found, followed by arsenite [As(III)] (mean 6.5 and 7.8 ng m(-3) for As(V), mean 1.2 and 2.1 ng m(-3) for As(III), in 2001 and 2002, respectively). The high levels of arsenic species found in PM10 in Huelva have a predominant industrial origin, such as the one from a nearby copper smelter, and do not present a seasonal pattern. The highest daily levels of arsenic species correspond to synoptic conditions in which the winds with S and SW components transport the contaminants from the main emission source. The frequent African dust outbreaks over Huelva may result in an increment of mass levels of PM10, but do not represent a significant input of arsenic in comparison to the anthropogenic source. The rural background levels of arsenic around Huelva are rather high, in comparison to other rural or urban areas in Spain, showing a relatively high atmosphere residence time of arsenic. This work shows the importance of arsenic speciation in studies of aerosol chemistry, due to the presence of arsenic species [As(III) and As(V)] with distinct toxicity.