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Inhalation of particulate matter (PM) has been linked to serious adverse health effects, such as asthma, cardiovascular diseases and lung cancer. In the present study, coarse (PM10-2.5), accumulation mode (PM2.5-0.25), and quasi-ultrafine (PM0.25) particulates were collected inside twelve educative centers of Tarragona County (Catalonia, Spain) during two seasons (cold and warm). Chemical characterization of PM, as well as risk assessment were subsequently conducted in order to evaluate respiratory and digestive risks during school time for children. Levels and chemical composition of PM were very different among the 12 centers. Average PM levels were higher during the cold season, as well as the concentrations of most toxic metals. In most schools, PM levels were below the daily PM10 threshold established in the regulation (50 μg/m3), with the exception of school number 1 during the cold season. On average, and regardless of season, coarse PM was highly influenced by mineral matter, while organic matter and elemental carbon were prevalent in quasi-ultrafine PM. The concentrations of the toxic elements considered by the legislation (As, Cd, Pb, and Ni) were below their correspondent regulatory annual limits. Calculated risks were below the safety thresholds, being fine fractions (PM2.5-0.25 and PM0.25) the main contributors to both digestive and respiratory risks.

The concentrations of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in 40 plasma samples of individuals living in zones under potential influence of the emissions of a hazardous waste incinerator (HWI) (Tarragona County, Catalonia, Spain). Samples corresponded to subjects of different gender, age and specific areas of residence. The levels of PCDD/Fs were compared to those obtained in a baseline study (1998), as well as in previous surveys (2002, 2007 and 2012). The current mean concentration of PCDD/Fs in plasma was 6.79 pg I-TEQ/g lipid, which was significantly lower than the baseline concentration (27.0 pg I-TEQ/g lipid). A significant decrease was also observed in comparison to the results obtained in 2002 and 2007 (15.7 and 9.4 pg I-TEQ/g, respectively), while the current PCDD/F levels were similar to those obtained in 2012 (6.18 pg I-TEQ/g lipid). This important reduction in plasma PCDD/F levels is in accordance with the decreasing trend in the daily dietary intake of PCDD/Fs, which diminished from 210.1 pg I-TEQ (baseline) to 8.54 pg WHO-TEQ (current). OCDD was the predominant congener in plasma, while 2,3,7,8-TeCDD and 1,2,3,4,7,8,9-HpCDF showed the lowest levels. Based on the above results, as well as other recent data on the levels of PCDD/Fs in human milk, we conclude that the presence of the HWI does not mean additional and significant risks –as regards to PCDD/F exposure-for the population living in the neighborhood of the facility.

In 2009, a cement plant located in Alcanar (South Catalonia, Spain) started co-processing a special kind of refuse-derived fuel (RDF) called ENERFUEL™. In April 2014 and 2017, 5 and 8 years after RDF co-processing, the concentrations of metals and metalloids (As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Sb, Tl, V and Zn) and PCDD/Fs were measured in samples of soils, herbage and air collected in the vicinity of the facility. The comparison of the current concentrations with those obtained in a baseline study (2008), when fossil fuels were used solely, has shown that the environmental concentrations of metals, metalloids and PCDD/Fs were not significantly modified. The concentrations of metals, metalloids and PCDD/Fs in soil, vegetation and air of Alcanar are in the low part of the ranges found around other cement plants in Catalonia (in general, below 50th percentile). Non-carcinogenic risks due to exposure to metals, metalloids and PCDD/Fs were lower than the safety value (HQ

A combined assessment on the levels and distribution profiles of polycyclic aromatic hydrocarbons (PAHs) and trace elements in soils from Pyramiden (Central Spitsbergen, Svalbard Archipelago) is here reported. As previously stated, long-range atmospheric transport, coal deposits and previous mining extractions, as well as the stack emissions of two operative power plants at this settlement are considered as potential sources of pollution. Eight top-layer soil samples were collected and analysed for the 16 US EPA priority PAHs and for 15 trace elements (As, Be, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sn, Tl, V and Zn) during late summer of 2014. The highest levels of PAHs and trace elements were found in sampling sites located near two power plants, and at downwind from these sites. The current PAH concentrations were even higher than typical threshold values. The determination of the pyrogenic molecular diagnostic ratios (MDRs) in most samples revealed that fossil fuel burning might be heavily contributing to the PAHs levels. Two different indices, the Pollution Load Index (PLI) and the Geoaccumulation Index (Igeo), were determined for assessing soil samples with respect to trace elements pollution. Samples collected close to the power plants were found to be slightly and moderately polluted with zinc (Zn) and mercury (Hg), respectively. The Spearman correlation showed significant correlations between the concentrations of 16 PAHs and some trace elements (Pb, V, Hg, Cu, Zn, Sn, Be) with the organic matter content, indicating that soil properties play a key role for pollutant retention in the Arctic soils. Furthermore, the correlations between ∑16 PAHs and some trace elements (e.g., Hg, Pb, Zn and Cu) suggest that the main source of contamination is probably pyrogenic, although the biogenic and petrogenic origin of PAHs should not be disregarded according to the local geology.

The photodegradation of polycyclic aromatic hydrocarbons (PAHs) may be an important degradation pathway of PAHs in regions with a high solar radiation. The present investigation was aimed at studying the photodegradation of PAHs after their deposition on surface soils with different textures. Photodegradation by-products were also identified and semi-quantified, as well as correlated with the decrease of parent compounds. The experiment was performed by deploying soil samples spiked with a mixture of the 16 US EPA priority PAHs in a methacrylate box, exposed to solar radiation for 7 days, meaning a solar energy of 102.6 MJ m − 2 . As hypothesized, the individual PAHs were volatilized, sorbed and/or photodegraded, depending on their physicochemical properties, as well as the soil characteristics. Low and medium molecular weight PAHs were more sorbed and photodegraded in fine-textured Regosol soil, while a higher volatilization was observed in the coarse-textured Arenosol soil. In contrast, high molecular weight PAHs were more photodegraded in Arenosol soil. Specially low half-lives were noted for anthracene and benzo( a )pyrene, agreeing with previous findings at laboratory scale. Nine by-products were identified, including oxy-, nitro- and hydro-PAHs, whose toxic and mutagenic potential might be higher than the 16 priority PAHs.

Polycyclic aromatic hydrocarbons (PAHs) are airborne pollutants that are deposited on soils. As climate change is already altering temperature and solar radiation, the global warming is suggested to impact the environmental fate of PAHs. This study was aimed at evaluating the effect of climate change on the PAH photodegradation in soils. Samples of Mediterranean soils were subjected to different temperature and light radiation conditions in a climate chamber. Two climate scenarios were considered according to IPCC projections: 1) a base (B) scenario, being temperature and light intensity 20 °C and 9.6 W/m2, respectively, and 2) a climate change (CC) scenario, working at 24 °C and 24 W/m2, respectively. As expected, low molecular weight PAHs were rapidly volatilized when increasing both temperature and light intensity. In contrast, medium and high molecular weight PAHs presented different photodegradation rates in soils with different texture, which was likely related to the amount of photocatalysts contained in both soils. In turn, the hydrogen isotopic composition of some of the PAHs under study was also investigated to verify any degradation process. Hydrogen isotopes confirmed that benzo(a)pyrene is degraded in both B and CC scenarios, not only under light but also in the darkness, revealing unknown degradation processes occurring when light is lacking. Potential generation pathways of PAH photodegradation by-products were also suggested, being a higher number of metabolites formed in the CC scenario. Consequently, in a more or less near future, although humans might be less exposed to PAHs, they could be exposed to new metabolites of these pollutants, which might be even more toxic. Keywords: Climate change, Polycyclic aromatic hydrocarbons (PAHs), Photodegradation, Metabolites, Hydrogen isotopes

Particulate matter (PM) is widely recorded as a source of diseases, being more harmful those particles with smaller size. PM is released to the environment as a consequence of different activities, being one of them cement production. The objective of this pilot study was to characterize PM of different sizes around cement facilities to have a preliminary approach of their origin, and evaluate their potential health risks. For that purpose, three fractions of PM (10, 2.5, and 1) were collected in the nearby area of two cement plants with different backgrounds (urban and rural) in different seasons. Subsequently, main components, outdoor and indoor concentrations, exposure, and human health risks were assessed. Greatest levels of PM 1 , organic matter, and metals were found in urban location, especially in winter. Consequently, environmental exposure and human health risks registered their highest values in the urban plant during wintertime. Exposure was higher for indoor activities, expressing some metals their peak values in the PM 1 fraction. Non-carcinogenic risks were below the safety threshold (HQ −5 , except for Cr (VI), which exceeded it in both locations, but being in the range considered as assumable (10 −6 –10 −4 ).

Heat treatment of harvested fruit has been demonstrated to be an effective and a safe approach for managing postharvest decay. In the present study, the effect of a hot water treatment (HT) (45. °C for 10. min) on the response of apple to blue mold infection was investigated. HT was applied to 'Ultima Gala' apples using 2 different methods. Wounded apples were: (1) inoculated with a Penicillium expansum spore suspension and then heat-treated after 1, 4 and 24. h (Inoc-HT); or (2) first heat-treated and then inoculated with a P. expansum spore suspension after 1, 4 and 24. h (HT-Inoc). All treated/inoculated apples were stored at 20. °C for 6 days. Significant reductions in fruit rot incidence, up to 100%, were observed using the Inoc-HT protocol at 4 and 24. h while a 30% reduction in blue mold incidence was found at 1 and 4. h using the HT-Inoc method. In vitro experiments showed no evident lethal effect of HT at 45. °C for 10. min on the germination of P. expansum conidia, indicating that this pathogen has a high heat tolerance. In order to investigate the molecular mechanisms involved in fruit response to heat treatment, an apple microarray was used to conduct a global transcriptional analysis of gene expression in apple at 0, 15, 30. min, 1, 4, 8 and 24. h after the heat treatment. The results provided evidence that at 1 and 4. h after heating, the HT apples had the highest number of differentially expressed genes. A significant upregulation of heat shock proteins, heat shock cognate protein, and heat shock transcription factor genes, involved in thermotolerance were observed. This indicates that the apple fruit respond to the heat treatment in a programmed manner and suggests that the genes responsible for thermotolerance may also be involved in the induced resistance response.

Data concerning atmospheric lifetime and relative source contributions of polycyclic aromatic hydrocarbons (PAH) are fragmentary and contradictory. In this study, two datasets of measurements of atmospheric PAH (sum of particulate and gaseous phases), one from a national network, the other from a more local three-site study, were analysed and used to infer processes affecting PAH in the atmosphere, and their sources. PAH congener profiles measured at urban and rural locations were remarkably similar suggesting that atmospheric decay processes are relatively slow. This allows the use of such profiles to elucidate sources. A spatial analysis of two PAH datasets showed a clear influence of industry and road traffic upon local PAH concentrations. When Principal Component Analysis (PCA) was applied to UK national network data, it showed a clear influence of steel industry emissions and of home heating emissions from coal and oil in Northern Ireland. These sites also showed different winter/summer concentration ratios to the main group of sites. In the data from Birmingham (UK), PCA identified separate factors relating to gasoline and diesel vehicles, as well as the influence of wood combustion on "Bonfire night", and a factor related to home heating emissions which shows up only in the cold season.

Comprehensive health risk assessment based on aggregate exposure and cumulative risk calculations requires a better understanding of exposure variables and uncertainty associated with them. Although there are many sources of uncertainty in system models, two basic kinds of parametric uncertainty are fundamentally different from each other: natural/stochastic and epistemic uncertainties. However, conventional methods such as standard Monte Carlo Sampling (MCS), which assumes vagueness as random property, may not be suitable for this type of uncertainty analysis. An improved systematic uncertainty and variability analysis can provide insight into the level of confidence in model estimates, and it can aid in assessing how various possible model estimates should be weighed. The main goal of the present study was to introduce Fuzzy Latin Hypercube Sampling (FLHS), a hybrid approach for incorporating epistemic and stochastic uncertainties separately. An important property of this technique is its ability to merge inexact generated data of the LHS approach to increase the quality of information. The FLHS technique ensures that the entire range of each variable is sampled with proper incorporation of uncertainty and variability. A fuzzified statistical summary of the model results produces a detailed sensitivity analysis, which relates the effects of variability and uncertainty of input variables to model predictions. The feasibility of the method has been tested with a case study, analyzing total variance in the calculation of incremental lifetime risks due to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) for the residents living in the surroundings of a municipal solid waste incinerator (MSWI) in the Basque Country, Spain.

In 2005 and 2006, the levels of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), polychlorinated biphenyls (PCBs) and metals (As, Be, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sn, Tl and V) were measured in air samples collected in an industrial area of Sant Adrià del Besòs (Barcelona, Catalonia, Spain) where a municipal solid waste incinerator (MSWI) is placed, and in a background/control area. In general terms, concentrations of all environmental pollutants were higher at the industrial site. No significant seasonal/temporal variations were observed in any of the areas. No Pearson correlation was found between the PCDD/F concentrations and the environmental conditions of the two sampling periods considered. Principal component analyses (PCA) were performed to get information on the relationship among samples, pollutants, and emission sources. The results indicate that the MSWI of S. Adrià de Besòs is not a significant emission source of the above compounds for the area under its direct influence. Moreover, a notable difference in the PCDD/F congener profiles was found between ambient air and stack gas emissions, indicating that the current levels of PCDD/Fs are more related to other potential emissions sources rather than to those from the MSWI.

The concentrations of polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polychlorinated biphenyls (PCBs) and polychlorinated naphthalenes (PCNs) were determined in air samples collected at four sampling sites located in two zones of Barcelona (Spain): near a municipal solid waste incinerator (MSWI) and a combined cycle power plant (3 sites), and at a background/control site. Samples were collected using high-volume active samplers. Moreover, 4 PUF passive samplers were deployed at the same sampling points during three months. For PCDD/Fs, total WHO-TEQ values were 27.3 and 10.9 fg WHO-TEQm(-3) at the urban/industrial and the background sites, respectively. The sum of 7 PCB congeners and the Sigma PCN levels were also higher at the industrial site than at the background site. In order to compare active and passive sampling, the accumulated amounts of PCDD/Fs, PCBs and PCNs in the four passive air samplers, as well as the total toxic equivalents in each sampling site were also determined. To assess the use of PUF passive samplers as a complementary tool for PCDD/F, PCB and PCN monitoring, sampling rates were calculated in accordance with the theory of passive air samplers. PUF disks allowed establishing differences among zones for the POP levels, showing that they can be a suitable method to determine POP concentrations in air in areas with various potential emission sources. Although both particle and gas phase were sorbed by the PUFs, data of gas phase congeners are more reproducible.

The aim of this study was to measure, 6 years after regular operations, the concentrations of a number of organic substances in blood and urine of 19 workers employed at a hazardous waste incinerator (HWI) in Spain, and to establish the temporal variation with respect to baseline data and previously performed surveys. This facility was the first, and so far the only HWI in that country. The levels of hexachlorobenzene (HCB), polychlorinated biphenyls (PCB 28, 52, 101, 138, 153 and 180) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were analyzed in six composite plasma samples, while concentrations of di-, tri, and pentachlorophenols, as well those of 1-hydroxypyrene were measured in the urine of these workers. The current mean PCDD/F concentration, 10.4 ng I-TEQ/kg lipid, was significantly lower than that found in the baseline survey, 26.7 ng I-TEQ/kg lipid and similar to that found in the previous (2004) study (7.7 ng I-TEQ/kg lipid). PCDD/F levels in plasma were similar or even lower than those recently reported for various non-exposed populations. For the remaining analyzed substances in plasma and urine, there was not any significant increase in comparison with the levels found in the baseline survey. On the other hand, no marked differences between the concentrations of organic substances in plasma or urine were found according to the respective workplace (plant, laboratory and administration). The results of the present survey indicate that after 6 years of regular operation, the workers at the HWI are not occupationally exposed to PCDD/Fs and other organic substances in their workplaces.

The possibility of employing antagonistic bacteria for postharvest control of gray mold on pear was studied. Approximately 175 strains of bacteria were isolated from beneath the skin of various fruits and vegetables and 14 of these possessed high levels of antagonistic properties. They significantly reduced gray mold in cv Conference pear artificially inoculated withBotrytis cinereaand stored at 20°C for at least 9 days. Two strains, 3PPE (Bacillus pumilus) and 2TOE (Bacillus amyloliquefaciens), were particularly active. They did not produce antibiotic substances and their application was compatible with iprodione-based antifungal treatments. The bacterial antagonist mixed with the fungicide at 50 ppm a.i. resulted in a greater control of the pathogen compared to the single ingredient. Holding bacteria-treated fruits at 20°C for 24 h before cold storage improved the efficacy of the bacteria against gray mold.

Endophytic bacteria were tested in the postharvest biocontrol of Monilinia laxa and Rhizopus stolonifer in stone fruits. Of a total of 122 strains of these sub-epidermis micro-organisms isolated from various horticultural sources (cucumber, eggplant, pepper, tomato, zucchini, apricot, peach and plum), approximately twenty showed greater than 90% control of the given pathogens. R. stolonifer appeared to be less susceptible than M. laxa to the endophytes. The influence of conidial concentration of M. laxa and of antagonist/pathogen contact time on the effectiveness of biocontrol were also evaluated.

Trichoderma viride, T. harzianum, Gliocladium roseum and Paecilomyces variotii were tested in biocontrol trials against several postharvest pathogens and compared with conventional fungicides. Applied as spray treatments to the fruits, these fungi partially controlled Botrytis cinerea, in strawberry and kiwifruit, Fusarium oxysporum in potato and Alternaria citri in lemon. Trichoderma demonstrated significant control of artificially inoculated B. cinerea in strawberry but proved ineffective against latent infections. Several strains of Trichoderma were found to be pathogenic in kiwifruit and lemon. All three fungal species gave poor mycelial development at 0, 2, 5, and 10°C storage temperatures, resulting in unsuccessful fruit colonization. The overall data indicate some of the difficulties in developing biological control techniques using Trichoderma, Gliocladium and Paecilomyces.