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Chemical industries and oil refineries are known emission sources of environmental contaminants, such as metals/metalloids, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), among others. Based on the toxicological potential of these pollutants, harmful health effects can be expected for the population living near these facilities. One of the largest chemical/petrochemical complexes in Europe is located in Tarragona County (Catalonia, Spain). In the last two decades, a number of investigations aimed at assessing the environmental impact of air pollutants potentially emitted by this industrial complex have been carried out. The present paper is a review of the available scientific information on the levels of air pollutants related with the activities of this chemical/ petrochemical complex. Although there are currently some data on the environmental burdens of metals/ metalloids, PAHs, VOCs and PCDD/Fs, there is an evident lack of specific biological monitoring studies on human health. Taking into account the amount of chemicals released to air and their toxicity, it is essential to perform an in-depth analysis of the current health status of the population living in Tarragona County.(c) 2021 The Author(s). Published by Elsevier B.V. This is an open access article under the CC BY license(http://creativecommons.org/licenses/by/4.0/).

Полициклични ароматични угљоводоници, ПAУ (енгл. polycyclic aromatic hydrocarbons), представљају једне од најраспрострањенијих загађивача. Прерада и изливање нафте као и спаљивање органске материје и употреба фосилних горива представљају главне путеве којима ПAУ и њихови деривати доспевају у животну средину, где се путем хемијских реакција могу превести у окси-, нитро- и друге деривате. ПAУ су често мутагени и канцерогени, а неки од њих могу бити и тератогени. У литератури ипак постоји мало података о многим од ових молекула, међу којима су деривати нафталена, антрацена, дибензофурана и бензантрона. У овом раду приказани су резултати теоријског проучавања изомера нитродибензофурана (НДФ), динитродибензофурана (ДНДФ), нитробензантрона (НБА), диметилнафталена (ДМН) и диметилантрацена (ДМА)..., Polycyclic aromatic hydrocarbons, PAHs, are one of the most widespread class of the pollutants. Processing and spilling of the crude oil as well as the organic matter combustion and usage of the fossil fuels are major paths by which PAHs and their derivatives reach the environment where through chemical reactions can be converted into the oxy, nitro, and other derivatives. PAHs are often mutagens and carcinogens and some of them may be teratogenic. However, there is little data in the literature on many of these molecules among which are the derivatives of naphthalene, anthracene, dibenzofuran and benzanthrone. In this thesis the results of a theoretical investigation of nitrodibenzofurans (NDFs), dinitrodibenzofurans (DNDFs), nitrobenzanthrones (NBAs), dimethylnaphtalenes (DMNs) and dimethylantracenes (DMAs) isomers are presented...

[EN]: The development of sorbents based on natural materials to immobilize pollutants in soils is an area of great interest, because of its growing need. Through the interaction of two natural smectitic clays (SWy-2 and Bailén), a synthetic hydrotalcite (HT) and its product of calcination (HT500) with the soluble organic matter (MOS) of an olive mill waste (alperujo) we obtained biosorbents, which can emulate the organo-mineral complex of soil and thus be used as natural amendments to reduce the mobility of organic pollutants in soils. Four sorbents were prepared, characterized and assayed against four contaminants: three herbicides (diuron, terbuthylazine and terbutryn) and dibenzofuran and its possible formation in situ. These biosorbents showed an increase in the adsorption of contaminants between 90 and 4%, depending on the clay and the contaminant, with respect to the raw materials. The more hydrophobic compounds (dibenzofuran and terbutryn) and the biosmectites displayed better performance by penetration of the MOS in the interlayer space of the clays. Amendment of soil with the original clays followed by addition of the contaminant in the presence of the MOS of alperujo showed a large increase of terbutryn and dibenzofuran retention in soil, evidencing the in situ formation of these adsorbents., [ES]: El desarrollo de adsorbentes basados en materiales naturales para inmovilizar contaminantes en suelos es un área de gran interés, por su creciente necesidad. Mediante la interacción de dos arcillas naturales esmectíticas (SWy-2 y Bailén), una hidrotalcita sintética (HT) y su producto de calcinación (HT500) con la materia orgánica soluble (MOS) de un alperujo se obtienen bioadsorbentes, que puedan emular al complejo organo-mineral del suelo y así ser utilizados como enmendantes naturales para disminuir la movilidad de contaminantes orgánicos en suelos.Se prepararon quatroadsorbentes, se caracterizaron y se ensayaron frente a quatro contaminantes: tres- herbicidas (diurón, terbutilazina y terbutrina) y el dibenzofurano y su posible formación in situ. Estos bioadsorbentes presentaron un aumento en la adsorción de contaminantes de entre el 90 y el 4%, dependiendo de la arcilla y el contaminante, respecto a las materias primas. Los compuestos más hidrófobos (dibenzofurano y terbutrina) y las bioesmectitas muestran los mejores resultados por penetración interlaminar de la MOS. La enmienda previa de un suelo con las arcillas originales seguida de la adición del contaminante en presencia de la MOS de alperujo muestra un gran aumento de la retención de terbutrina y dibenzofurano en el suelo, evidenciando la formación in situ de estos adsorbentes.

The hydrodeoxygenation (HDO) of dibenzofuran (DBF) was investigated over silica-supported nickel phosphide catalysts with low metallic loadings (2.5–10 wt.%) and with different initial P/Ni atomic ratios. The formation of the nickel phosphide phase as well as the textural, structural and acidic properties of the catalysts were evaluated by X-ray fluorescence (XRFS), H2-temperature programmed reduction (H2-TPR), X-ray diffraction (XRD), CO chemisorption at 35 °C, N2 adsorption–desorption isotherms at −196 °C, NH3-temperature programmed desorption (NH3-TPD) and elemental analysis (CNHS). The effect of metallic loading, the initial P/Ni molar ratio as well as the feed O-concentration on the catalytic activity were studied. Characterization results reveal that smaller particle sizes are formed at lower metallic loadings and high P/Ni atomic ratios, and that the acidity increases linearly with the metallic loading pointing to nickel and phosphorous species as the acidic centers in reduced catalysts. Nickel phosphide catalysts display good activity and stability in the HDO of DBF, reaching high DBF conversion values at moderate temperatures (300 °C) and with high selectivity to bicyclohexane (BCH), the main deoxygenated product which was obtained by hydrogenation of both aromatic rings (HYD pathway). Catalyst deactivation due to coke was minimal due to the low strength of the acid sites, while the formation of water did not present an inhibiting effect even under high O-concentration. This behavior might occur because water interacts preferentially with the excess phosphorous present on the catalyst surface and thus nickel phosphide particles do not undergo oxidation.

Microbialites flourished globally immediately following the latest Permian mass extinction. In this study, lipid biomarker records were analyzed in the Cili section (Hunan Province, South China) in order to determine the types of microbes involved in microbialite formation and their response to contemporaneous environmental changes. Various biomarkers were identified in the aliphatic and aromatic fractions using gas chromatography (GC) and GC–mass spectrometry (GC–MS). Low abundance of steranes in the microbialite layer suggests that it did not contain large amounts of algae, in striking contrast to the abundant algal fossils and algal-derived steranes present in the underlying (pre-crisis) skeletal limestone. Although pristine/phytane (Pr/Ph) ratios increased in the microbialite layer, covariation of Pr/Ph with the ratio of low- to high-molecular-weight n-alkanes (C20 −/C20 +) suggests that the former proxy was controlled by microbial (particularly cyanobacterial) inputs rather than by redox conditions.The microbialite also yielded low ratios of hopanes to short-chain n-alkanes (HP/Lalk) and high abundances of C21n-alkylcyclohexane, indicating that, in addition to cyanobacteria, anaerobic bacteria, archaea, and possibly acritarchs flourished in the aftermath of the marine extinction event. The upper part of the thinly bedded micritic limestone overlying the microbialite exhibits a bimodal distribution of n-alkanes as well as increased abundances of extended tricyclic terpanes and steranes, suggesting a return of habitable shallow-marine conditions for eukaryotic algae several hundred thousand years after the latest Permian mass extinction. Increases in the dibenzofuran ratio (i.e., DBF/(DBF + DBT + F)) and in the coronene to phenanthrene ratio (Cor/P) in the skeletal limestone immediately below the microbialite are evidence of enhanced soil erosion rates and wildfire intensity, marking the collapse of terrestrial ecosystems. The terrestrial crisis thus slightly pre

Objectives: In Sweden, an important source for exposure to persistent organochlorine pollutants, such as PCDD and PCDF, is through intake of fatty fish from the Baltic Sea off the Eastern coast of Sweden. The present study assesses temporal trends for human levels of PCDD/F between 1987 and 2002 among 26 men from Sweden. In addition, we investigate the impact of potential determinants (age, relative change in BMI and fish consumption) on the relatively change in individual PCDD/F congener levels between 1987 and 2002. Methods: In 1987, nine of the men did not eat fatty fish from the Baltic Sea, eight had a moderate intake, and nine were high consumers. For the same individuals,blood samples were collected in 1987 as well as in 2002, and the concentrations of seven PCDD and 10 PCDF congeners were analyzed at the same laboratory. Results: The WHO-TEQ levels for PCDD/F did not significantly change over the 15-year period. There were, however, some specific congeners that significantly had changed over time. None of the investigated determinants were associated with the change over time for the specific PCDD/F congeners. Conclusion: The present study may be of importance for risk assessment and setting standards for food contamination with PCDD/F, especially regarding intake of fatty fish from the Baltic Sea.