Particulate matter from a tropical city in southeast Brazil: Impact of biomass burning on polycyclic aromatic compounds levels, health risks, and in vitro toxicity.

In the context of a rising global temperature, biomass burning represents an increasing risk to human health, due to emissions of highly toxic substances such as polycyclic aromatic hydrocarbon (PAHs). Size-segregated particulate matter (PM) was collected in a region within the sugarcane belt of São Paulo state (Brazil), where biomass burning is still frequent, despite the phasing out of manual harvesting preceded by fire. The median of the total concentration of the 15 PAHs determined was 2.3 ± 1.8 ng m-3 (n = 19), where 63% of this content was in PM1.0. Concentrations of OPAHs and NPAHs were about an order of magnitude lower. PM2.5 collected in the dry season, when most of the fires occur, presented PAHs and OPAHs total concentrations three times higher than in the wet season, showing positive correlations with fire foci number and levoglucosan (a biomass burning marker). These results, added to the fact that biomass burning explained 65% of the data variance (PCA analysis), evidenced the importance of this practice as a source of PAHs and OPAHs to the regional atmosphere. Conversely, NPAHs appeared to be mainly derived from diesel-powered vehicles. The B[a]P equivalent concentration was estimated to be 4 times higher in the dry season than in the wet season, and was greatly increased during a local fire event. Cytotoxicity and genotoxicity of PM1.0 organic extracts were assessed using in vitro tests with human liver HepG2 cells. For both types of tests, significant toxicity was only observed for samples collected during the dry season. Persistent DNA damage that may have impaired the DNA repair system was also observed. The results indicated that there was a health risk associated with the air particulate mixture, mainly related to biomass burning, demonstrating the urgent need for better remediation actions to prevent the occurrence of burning events.

Estudo computacional das propriedades ópticas não lineares de moléculas com potencial aplicação tecnológica / Computational study of nonlinear optical properties of molecules with potential technological application

[{"text": "Resumo: Existe um grande interesse no estudo de materiais moleculares que possuem propriedades\r\nópticas não lineares (ONL) visando potenciais aplicações tecnológicas, tais como em tecnologia da\r\ninformação. O uso de métodos baseados na mecânica quântica tem sido usado como uma alternativa\r\nna busca de novos materiais com aplicação em ONL. No entanto, a previsão teórica das propriedades\r\nONL é muito dependente do protocolo computacional (método de mecânica quântica, funções de\r\nbase, efeitos da correlação eletrônica e do meio). Assim, no presente estudo foi realizada uma\r\nvalidação dos protocolos computacionais CAM-B3LYP/NLO-V e CAM-B3LYP/aNLO-V (J. Mol.\r\nModel. 19 (2013) 2079-2090) propostos anteriormente para um conjunto de quatro moléculas\r\norgânicas com valores de primeira hiperpolarizabilidade (ß) variando entre 52 e 190×10-30esu. Além\r\ndisso, os efeitos do meio também foram avaliados considerando os modelos implícitos de solvatação\r\nIEF-PCM, CPCM e SMD. No geral, os resultados obtidos estão dentro da faixa de erro de ±20% das\r\nmedidas experimentais, com os protocolos computacionais CAM-B3LYP/aNLO-V/IEF-PCM (UFF)\r\ne CAM-B3LYP/aNLO-V/SMD descrevendo adequadamente a tendência observada dos valores\r\nexperimentais. O valor de ß calculado com o protocolo CAM-B3LYP/aNLO-V/SMD apresentou um\r\ndesvio relativo de apenas 0,7% para a molécula DIA (ß ), que apresenta o

Simultaneous quantification of volatile fatty acids and nonvolatile organic acids in Hevea brasiliensis latex.

The current method used in latex industries to determine the volatile fatty acids contents of Hevea brasiliensis latex is steam distillation. However, the accuracy of the method has been debated for some time. We assessed the accuracy of the method and developed a new, more reliable high-performance liquid chromatographic method of determining acids in latex. The volatile fatty acids (formic, acetic, propionic, butyric, and valeric acids) and nonvolatile organic acids (oxalic, malic, lactic, citric, and succinic acids) in latex are directly determined simultaneously for the first time with high sensitivity and without losses during sample preparation. To avoid errors from derivatization, an acid-resistant Prevail HPLC column and a gradient mobile phase of 25 mM potassium dihydrogen phosphate (pH 2.5) and acetonitrile were employed. Under optimum conditions, the calibrations of both types of acids demonstrated satisfactory correlation coefficients of  ≥0.990, with limits of detection ranging from 0.02 to 395 mM. The developed method demonstrated the profiles of acids in field and concentrated latex of the same batch. Moreover, the evolution of the profiles of all studied acids in both types of latex during a 3-month period was also revealed.

Effect of mixed organic and inorganic fertilizers on growth, leaf macronutrient contents and yield of pitaya(Hylocereus undatus) under field conditions / Efeito da combinação de fertilizantes orgânicos e inorgânicos no crescimento, conteúdo de macronutrientes nas folhase rendimento de pitaya (Hylocereus undatus) emcondições de campo

This study aimed to evaluate the effect of organic and inorganic fertilizers on the pitaya’s Hylocereus undatusperformance under field conditions. The experimental design used was Completely Randomized Block Design (CRBD). Five treatments consisting of the four different fertilizer dosages were included in this study, namely T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) and T5 (Control: 00-000-000-000) of bovine manure (kg pit-1), urea (g pit-1), super simple (g pit-1) and potassium chloride (g pit-1), respectively. Parameters such as height, number, length, width, area, and volume of the cladodes were assessed at 20 and 320 days after planting. The number of fruits produced and mineral composition (N, K, Ca, Mg, P, and S) of H. undatusplants were also assessed. The results on morphometric characteristics of the cladodes, macronutrient composition and fruit yield have been recorded with higher values in treatments 3 and 4. However, according to the principal component analysis performed, treatment 3 was the one that correlated with the evaluated characteristics. The results have clearly indicatedthe importance of combination of adequate dose of mineral and organic fertilizer for better vegetative performance and yield of pitaya crop.

Este estudo tevepor objetivoavaliar o efeito defertilizantes orgânicos e inorgânicos sobre o desempenho da pitayaHylocereus undatusem condições de campo.O delineamento experimental utilizado foi Delineamento emBlocos Completamente Casualizados (DBC).Foram incluídos neste estudo cinco tratamentos constituídos por quatro diferentes dosagens de fertilizantes, nomeadamente T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) e T5 (Controle: 00-000-000-000) de estercobovino (kg cova-1), ureia (g cova-1), super simples (g cova-1) e cloreto de potássio (g cova-1), respectivamente. Parâmetros como altura, número, comprimento, largura, área e volume dos cladódios foram avaliados aos 20 e 320 dias após oplantio.O número de frutos produzidos e a composição mineral (N, K, Ca, Mg, P, e S) das plantas H. undatusforam também avaliados. Os resultados sobre as características morfométricas dos cladódios, composição de macronutrientes e rendimento de frutos foram registados com valores mais elevados nos tratamentos 3 e 4. No entanto, de acordo com a análise dos componentes principais (PCA) realizada, o tratamento 3 foi o que mais se correlacionou com as características avaliadas. Os resultados indicaram claramente a importância da combinação de doses adequadas de fertilizante mineral e orgânico para um melhor desempenho vegetativo e rendimento da cultura da pitaya.

Effect of mixed organic and inorganic fertilizers on growth, leaf macronutrient contents and yield of pitaya(Hylocereus undatus) under field conditions / Efeito da combinação de fertilizantes orgânicos e inorgânicos no crescimento, conteúdo de macronutrientes nas folhase rendimento de pitaya (Hylocereus undatus) emcondições de campo

This study aimed to evaluate the effect of organic and inorganic fertilizers on the pitayas Hylocereus undatusperformance under field conditions. The experimental design used was Completely Randomized Block Design (CRBD). Five treatments consisting of the four different fertilizer dosages were included in this study, namely T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) and T5 (Control: 00-000-000-000) of bovine manure (kg pit-1), urea (g pit-1), super simple (g pit-1) and potassium chloride (g pit-1), respectively. Parameters such as height, number, length, width, area, and volume of the cladodes were assessed at 20 and 320 days after planting. The number of fruits produced and mineral composition (N, K, Ca, Mg, P, and S) of H. undatusplants were also assessed. The results on morphometric characteristics of the cladodes, macronutrient composition and fruit yield have been recorded with higher values in treatments 3 and 4. However, according to the principal component analysis performed, treatment 3 was the one that correlated with the evaluated characteristics. The results have clearly indicatedthe importance of combination of adequate dose of mineral and organic fertilizer for better vegetative performance and yield of pitaya crop.(AU)

Este estudo tevepor objetivoavaliar o efeito defertilizantes orgânicos e inorgânicos sobre o desempenho da pitayaHylocereus undatusem condições de campo.O delineamento experimental utilizado foi Delineamento emBlocos Completamente Casualizados (DBC).Foram incluídos neste estudo cinco tratamentos constituídos por quatro diferentes dosagens de fertilizantes, nomeadamente T1 (00-120-320-120); T2 (04-080-160-080); T3 (06-060-100-060); T4 (08-000-000-000) e T5 (Controle: 00-000-000-000) de estercobovino (kg cova-1), ureia (g cova-1), super simples (g cova-1) e cloreto de potássio (g cova-1), respectivamente. Parâmetros como altura, número, comprimento, largura, área e volume dos cladódios foram avaliados aos 20 e 320 dias após oplantio.O número de frutos produzidos e a composição mineral (N, K, Ca, Mg, P, e S) das plantas H. undatusforam também avaliados. Os resultados sobre as características morfométricas dos cladódios, composição de macronutrientes e rendimento de frutos foram registados com valores mais elevados nos tratamentos 3 e 4. No entanto, de acordo com a análise dos componentes principais (PCA) realizada, o tratamento 3 foi o que mais se correlacionou com as características avaliadas. Os resultados indicaram claramente a importância da combinação de doses adequadas de fertilizante mineral e orgânico para um melhor desempenho vegetativo e rendimento da cultura da pitaya.(AU)

Primary and secondary organic winter aerosols in Mediterranean cities under different mixing layer conditions (Barcelona and Granada).

PM10 was collected during an EMEP winter campaign of 2017-2018 in two urban background sites in Barcelona (BCN) and Granada (GRA), two Mediterranean cities in the coast and inland, respectively. The concentrations of PM10, organic carbon (OC), elemental carbon (EC), and organic molecular tracer compounds such as hopanes, anhydro-saccharides, polycyclic aromatic hydrocarbon, and several biogenic and anthropogenic markers of secondary organic aerosols (SOA) were two times higher in GRA compared to BCN and related to the atmospheric mixing heights in the areas. Multivariate curve resolution (MCR-ALS) source apportionment analysis identified primary emissions sources (traffic + biomass burning) that were responsible for the 50% and 20% of the organic aerosol contributions in Granada and Barcelona, respectively. The contribution of biomass burning was higher in the holidays than in the working days in GRA while all primary combustion emissions decreased in holidays in BCN. The MCR-ALS identified that oxidative species and SOA formation processes contributed to 40% and 80% in Granada and Barcelona, respectively. Aged SOA was dominant in Granada and Barcelona under stagnant atmospheric conditions and in presence of air pollution. On the other hand, fresh SOA contributions from α-pinene oxidation (cis-pinonic acid) were three times higher in Barcelona than Granada and could be related to new particle formation, essentially due to overall cleaner air conditions and elevated air temperatures.

Plinia cauliflora (Mart.) Kausel: toxicological assays, biological activities, and elemental analysis of organic compounds.

Jaboticaba, Plinia cauliflora (Mart.) Kausel, is a Brazilian berry traditionally used in folk medicine as treatment for some health conditions. Phenolic compounds such as flavonoids and anthocyanins have previously been detected in the fruit. This current study aimed to evaluate the toxicological effects of jaboticaba peel extract (JPE) on Artemia salina, L929, and MDA-MB-231 cell lines. Besides, JPE antioxidant, acetylcholinesterase, and antifungal activities, and elemental analysis CHNS were also tested. JPE had moderate toxicity (LD50 = 360.92 µg mL-1) on A. salina, non-toxic effect on L929 cell line, and decreased the viability of cancer cell line MDA at 1,000 µg mL-1 and 500 µg mL-1 concentrations. The antioxidant activity toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) performed IC50 = 37.45 ± 0.17 µg mL-1, whereas 45.7% of acetylcholinesterase activity was inhibited. By its elemental composition, JPE is an alternative food supplement and dermocosmetic component. Antifungal potential toward Candida strains was not observed.

Monoglyceride oleogels as fat replacers in filling creams for sandwich cookies.

BACKGROUND: Many food products need to be reformulated to reduce the intake of saturated and trans fats which are considered unhealthy. In particular, the reformulation of filling creams (FCs) is challenging as these fats cannot be directly replaced with liquid oil without affecting the final product properties. This research studied the formulation and characterization of FCs for sandwich cookies using monoglyceride oleogel as fat material. RESULTS: FC formulated with 260 g kg-1 oleogel showed viscoelastic moduli values that did not differ significantly from those measured in a filling cream of commercial sandwich cookies (FC-CSCs) used as reference. The oil binding capacity of the FCs decreased with the increase of oleogel content. The increase of the oleogel amount in the formulation produced a decrease in hardness but an increase in adhesiveness and cohesiveness. Hardness, adhesiveness, and cohesiveness ranged from 0.66 to 3.48 N, 0.44 to 0.86 N s, and 0.07 to 0.29, respectively. When FCs were used for assembling cookies into sandwiches, an oil loss of about 9 g kg-1 FC after 21 days of storage was found in FCs containing 220 and 260 g kg-1 oleogel. The nutritional improvement due to the use of oleogel in FCs led to a reduction in saturated fatty acids between 64.5% and 35.2% and from 1.0 to 0.0% trans fatty acids in comparison with FC-CSC. CONCLUSION: Full fat replacement with monoglyceride oleogel in FC formulations allows the obtention of products with good quality and some similar characteristics to those obtained for FC-CSC, with the added benefit of a healthier nutritional profile. © 2020 Society of Chemical Industry.

Removal efficiency of dissolved organic matter from secondary effluent by coagulation-flocculation processes.

Wastewater reuse has been widely discussed as an essential strategy to minimize the consumption of drinking water for less noble purposes. During biological wastewater treatment, organic matter is converted into a complex matrix containing a variety of soluble organic compounds. The objective of the present study was to evaluate the removal efficiency of the residual organic load in the final effluent from wastewater treatment plant with a conventional activated sludge process by different coagulants and parameters of coagulation-flocculation process, using dissolved organic carbon (DOC) concentration, molecular weight (MW) size distribution by size exclusion chromatography (SEC) coupled to mass spectrometry (MS), and zeta potential (ZP) analyses. The results showed a DOC removal efficiency up to 45% with iron chloride, and of 38% for aluminum sulfate and 31% for PAC coagulants. ZP was also measured during the procedures and authors conclude that the ZP also does not have a determining role in these removals. SEC and MS assessment was able to detect changes on secondary effluent molecular weight distribution profile after effluent coagulation-flocculation, this technique might be a promising tool to understand the composition of effluent organic matter and be helpful to estimate and optimize the performance of wastewater effluents treatment processes.

Liver infusion tryptose (LIT): the best choice for growth, viability, and infectivity of Leishmania infantum parasites.

Leishmania spp. parasites have a complex biological cycle presenting basically two different morphological stages, the amastigote and promastigote forms. In vitro cultivation allows a more complete study of the biological aspects of these parasites, indicating better conditions for infection, immunoassay tests, drug evaluations, and vaccines. Thus, we evaluated the three most used culture media for Leishmania spp., Grace's insect cell culture medium (Grace's), liver infusion tryptose (LIT), and Schneider's insect medium (Schneider's), without supplementation or supplemented with fetal calf serum (FCS) and bovine serum albumin (Albumin) to evaluate the growth, viability, and infectivity of the L. infantum promastigotes. It was observed that promastigote forms have a better growth in LIT and Schneider's with or without FCS when compared to that in Grace's. The supplementation with albumin promoted greater viability of the parasites independent of the medium. For in vitro infection of J774.A1 macrophages using light microscopy and flow cytometry analyses, FCS-supplemented LIT and Grace's promoted higher percentage of infected macrophages and parasite load compared with Schneider's media. Taken together, our results demonstrated that the supplementation of LIT culture medium with FCS is the most suitable strategy to cultivate Leishmania infantum parasites enabling the maintenance of growth and infective parasites for research uses.

Potential Applicability of Cocoa Pulp (Theobroma cacao L) as an Adjunct for Beer Production.

The aim of this study was to evaluate the application of cocoa pulp as an adjunct for malt in beer production. The cocoa pulp was analyzed for humidity, proteins, lipids, sugars, total soluble solids, organic acids, and minerals. A study was carried out to reduce the cocoa pulp viscosity by enzymatic depectinization, making its use viable in beer production. The cocoa pulp showed relevant quantities of compounds important in fermentation, such as sugars, acids, and minerals. In fermentation using the adjunct, the proportions of pulp used were 10, 30, and 49%. A significant difference was found between the adjunct and all-malt worts. The 30% cocoa pulp concentration as an adjunct for malt in the fermentation medium contributed the most to the fermentative performance of the yeasts at both 15 and 22°C based on the consumption of apparent extract (°Plato), ethanol production, and cellular growth.

Copper and Zn distribution in humic substances of soil after 10 years of pig manure application in south of Santa Catarina, Brazil.

This study aims to evaluate available Cu and Zn levels in soil and related in soil organic matter (SOM) fractions (fulvic acids-FA, humic acids-HA, and humins-HU) after 10 years of application of pig slurry (PS) and pig deep litter (PL). Soil samples were collected from an experiment with black oat/corn succession under no-tillage in southern Brazil. The treatments consisted of fertilization of 90 and 180 kg N ha-1 applied as PS and PL from 2002 to 2012 and a control treatment without any fertilization. SOM chemical fractionation was performed in air-dried samples. Copper and Zn concentrations were analyzed in soil (total, EDTA- and CaCl2-extracted) and in SOM fractions. The amount of Cu and Zn (in mol) related to each fraction of SOM (Cu/C and Zn/C molar ratios) was established. The applications of PS and PL promoted the accumulation of total and available Cu and Zn, especially in the PL180 treatment. The highest amount of Zn was found with HU, while for Cu both HA and HU were important retention compartments. The highest Cu/CFA, Cu/CHA and Cu/CHU ratios were found with the addition of PL. Increases in Zn/C ratio were found mainly in FA fraction. The high levels of Cu and Zn obtained in the HCl-extracted SOM fraction suggest that a considerable part is bound to SOM and clay minerals with low energy. However, the SOM is an important source of metal adsorption in soils with swine manure application.

Biosignature Analysis of Mars Soil Analogs from the Atacama Desert: Challenges and Implications for Future Missions to Mars.

The detection of biosignatures on Mars is of outstanding interest in the current field of astrobiology and drives various fields of research, ranging from new sample collection strategies to the development of more sensitive detection techniques. Detailed analysis of the organic content in Mars analog materials collected from extreme environments on Earth improves the current understanding of biosignature preservation and detection under conditions similar to those of Mars. In this article, we examined the biological fingerprint of several locations in the Atacama Desert (Chile), which include different wet and dry, and intermediate to high elevation salt flats (also named salars). Liquid chromatography and multidimensional gas chromatography mass spectrometry measurement techniques were used for the detection and analysis of amino acids extracted from the salt crusts and sediments by using sophisticated extraction procedures. Illumina 16S amplicon sequencing was used for the identification of microbial communities associated with the different sample locations. Although amino acid load and organic carbon and nitrogen quantities were generally low, it was found that most of the samples harbored complex and versatile microbial communities, which were dominated by (extremely) halophilic microorganisms (most notably by species of the Archaeal family Halobacteriaceae). The dominance of salts (i.e., halites and sulfates) in the investigated samples leaves its mark on the composition of the microbial communities but does not appear to hinder the potential of life to flourish since it can clearly adapt to the higher concentrations. Although the Atacama Desert is one of the driest and harshest environments on Earth, it is shown that there are still sub-locations where life is able to maintain a foothold, and, as such, salt flats could be considered as interesting targets for future life exploration missions on Mars.

Collision Cross Section Calculations Using HPCCS.

A technical overview of the High Performance Collision Cross Section (HPCCS) software for accurate and efficient calculations of collision cross sections for molecular ions ranging from small organic molecules to large protein complexes is presented. The program uses helium or nitrogen as buffer gas with considerable gains in computer time compared to publicly available codes under the Trajectory Method approximation. HPCCS is freely available under the Academic Use License at https://github.com/cepid-cces/hpccs .

Dissolved major and trace geochemical dynamics in Antarctic lacustrine systems.

Clearwater Mesa (James Ross Island, northeast Antarctic Peninsula) provides a unique opportunity to study solute dynamics and geochemical weathering in the pristine lacustrine systems of a high latitude environment. In order to determine major controls on the solute composition of these habitats, a geochemical survey was conducted on 35 lakes. Differences between lakes were observed based on measured physico-chemical parameters, revealing neutral to alkaline waters with total dissolved solids (TDS) < 2500 mg L-1. Katerina and Trinidad-Tatana systems showed an increase in their respective TDS, total organic carbon values, and finner sediments from external to internal lakes, indicating an accumulation of solutes due to weathering. Norma and Florencia systems exhibited the most diluted and circumneutral waters, likely from the influence of glacier and snow melt. Finally, isolated lakes presented large variability in TDS values, indicating weathering and meltwater contributions at different proportions. Trace metal abundances revealed a volcanic mineral weathering source, except for Pb and Zn, which could potentially indicate atmospheric inputs. Geochemical modelling was also conducted on a subset of connected lakes to gain greater insight into processes determining solute composition, resulting in the weathering of salts, carbonates and silicates with the corresponding generation of clays. We found CO2 consumption accounted for 20-30% of the total species involved in weathering reactions. These observations allow insights into naturally occurring geochemical processes in a pristine environment, while also providing baseline data for future research assessing the impacts of anthropogenic pollution and the effects of climate change.

Air quality of an urban school in São Paulo city.

A major campaign was carried out in indoor and outdoor environments in a school located in the university campus of the city of São Paulo. Elements, PAH, oxy-PAH, water-soluble ions and black carbon were determined and compared with preliminary campaigns. The results indicated that the concentrations of particles and organic compounds were higher indoors. Some high molecular weight compounds, attributed to vehicular emissions, were more abundant outdoors. The associated health risk was found to be low. 2-Methylanthraquinone and benzo(a)anthracene-7,12-dione were detected in the indoor samples, denoting the infiltration of vehicle exhaust. The observation of black carbon also corroborates the contribution of traffic emissions. For most of the elements, except for chromium, iron and manganese, the concentrations obtained in indoors were higher than outdoors, mainly due to soil resuspension. Chromium and manganese likely derived from emissions of the vehicle powered by mixtures of ethanol and gasoline. Water-soluble inorganic ions species denoted the influence of soil resuspension and human activities.

Seasonal variation of the organic and inorganic composition of sugarcane vinasse: main implications for its environmental uses.

Sugarcane vinasse is the main waste stream of the Brazilian agroindustry. The typical composition of sugarcane vinasse gives it a high polluting potential that implies the necessity to define sustainable strategies for managing this waste. Knowledge of the inorganic and organic composition of vinasse and its seasonal variation is extremely important to conduct scientific research to define alternative managements for vinasse disposal other than fertigation. This study evaluated the variability of vinasse composition throughout the same harvesting season and among three harvesting seasons of one Brazilian annexed biorefinery (2015-2017). The contents of chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total solids (TS), suspended solids (SS), salinity (K+, Na+, Ca2+, Mg2+, Cl-, F-), nutrients (N, P, S), trace metals (Al3+, As2+, Ba2+, Cd2+, Cr3+, Co2+, Cu2+, Fe2+, Pb2+, Mn2+, Hg2+, Mo2+, Ni2+, Se2+, Zn2+), and specific soluble organic compounds (sugars, alcohols, and organic acids), as well as pH and conductivity, were monitored in 13 samples. The results indicated that sugarcane vinasse is a suitable feedstock for biological treatments, such as anaerobic digestion processes for energy recovery, as well as substrate for biomass (e.g., microalgae, energy crops, lignocellulosic biomass) growth. The application of a previous treatment makes vinasse a more environmentally friendly natural fertilizer for land fertigation.

First long-term record of halogenated organic compounds (AOX, EOX, and PCDD/F) and trace elements (Cd, Cr, Cu, Fe, Hg, Pb, Ni, and Zn) in marine biota of the coastal zone of southcentral Chile.

This paper reports long-term concentration records of metals and organic halogenated compounds in tissues of 49 species of marine organisms from Eastern South Pacific coast, Biobio region, Chile during a marine monitoring program developed between 2006 and 2015. Principal component (PCA) and generalized linear model (GLM) analyses indicated significant differences in the concentrations of metals and organic halogenated compounds among taxonomic and functional groups. The strongest relationships exist between species that share similar feeding habits rather than between species of the same taxonomic group or habitat. The significant differences between these groups were maintained over time; thus concentrations detected are, in general, within the ranges reported at genus level for Chile and the rest of the world. Since there is no evidence of any pollution process in the area, this information can be used as an environmental reference to establish natural concentrations for the parameters and organisms analyzed.

Stable isotopes and geochemical indicators in marine sediments as proxies for anthropogenic impact: A baseline for coastal environments of central Chile (33°S).

Stable isotopes and geochemical proxies (TOC/TN and Chla/TOC) in sediments can be used to distinguish organic matter sources (anthropogenic, terrestrial, or marine). This study aims to characterize organic matter (OM) in superficial sediments from three sectors of central Chile (33°S) that are highly influenced by urban and industrial development. Our results show that a substantial fraction of these OM in Quintero Bay is anthropogenic, from industrial and domestic wastewater sources. In contrast, a mixture of terrestrial and anthropogenic OM dominates the isotopic signal of surface sediments from Concón, derived from non-point industrial and agriculture sources associated with the Aconcagua River basin, while Ritoque exhibited a mixture of different OM sources. However, deposition of allochthonous OM in our study area depends on coastal topography, which influences the local currents and well-ventilated waters, promoting the dispersion and assimilation of OM and thus providing an environment with a high capacity for natural remediation.

Effect of platform subway depth on the presence of Airborne PM2.5, metals, and toxic organic species.

PM2.5 that have been related to public health risks, were collected during two seasons with High-Vol samplers in platforms of a Mexican subway station, which interconnects through transfers three lines having different depths. The objective was to study the influence of depth on the PM2.5 concentrations and their species. PM2.5 concentrations in cold-dry and warm-dry seasons presented statistical differences, being in average 57 and 66 µgm-3 respectively, in the shallower line 9; 90 µgm-3 and 111 µgm-3 in line 1; and 104 and 122 µgm-3in the deepest line 7. During the cold-dry season and warm-dry season PM2.5concentrations in the subway environment were respectively up to 3.5 times and up to 5 times greater than in the ambient air. Like PM2.5, metals analyzed with an OES-ICP presented higher concentrations in deeper lines as well as PAHs quantified with CG-MS, which ranged from 4.5 to 11.7 ngm-3. High PM2.5, metals and organic toxic concentrations found in deeper lines of the subway environment represent a risk for commuters endorsing the need for ventilation systems to reduce them. Zn, Pb, V and Ni in subway particles presented the highest solubility in artificial lysosomal fluid suggesting high bioavailability in the lung fluids.