Sorption of lead (Pb2+) from aqueous solutions using chars obtained in the pyrolysis of forestry pine, rubber tires and plastics

Carbonaceous solid products resulting from thermochemical processes (pyrolysis, gasification), commonly known as chars, are emerging as low-cost sorbents of metallic contaminants, being their effectiveness already demonstrated in several studies (Inyang et al., 2012; Fuente-Cuesta et al., 2012; Ko³odyñska et al., 2012; Quek and Balasubramanian, 2009; Devecia and Kar, 2013). Given the fact that the commercial viability of pyrolysis and gasification plants for the treatment and valorisation of waste streams are increasingly being demonstrated, it is expected that large amounts of solid chars will be available in a near future, as by-products or as main products (pyrolysis-carbonization). Chars may possess several characteristics which turn them effective as heavy metals sorbents: aromatic carbon matrix with relatively porous structures, the presence of functional groups or inorganic inclusions in the surface providing active sites to interact with metallic species (Inyang et al., 2012; Fuente-Cuesta et al., 2012; Ko³odyñska et al., 2012; Quek and Balasubramanian, 2009; Devecia and Kar, 2013; Lu et al., 2012). Lead (Pb2+) is considered as a priority substance in the field of European water policy (EU, 2000; EU, 2008) which means that measures shall be taken by the Member States to eliminate or reduce the water pollution caused by this pollutant in order to fulfill the emission/discharge limits legislated for this compound

Leaching behaviour and ecotoxicity evaluation of chars from the pyrolysis of forestry biomass and polymeric materials

The main objective of this study was to assess the environmental risk of chars derived from the pyrolysis of mixtures of pine, plastics, and scrap tires, by studying their leaching potential and ecotoxicity. Relationships between chemical composition and ecotoxicity were established to identify contaminants responsible for toxicity. Since metallic contaminants were the focus of the present study, an EDTA washing step was applied to the chars to selectively remove metals that can be responsible for the observed toxicity. The results indicated that the introduction of biomass to the pyrolysis feedstock enhanced the acidity of chars and promote the mobilisation of inorganic compounds. Chars resulting from the pyrolysis of blends of pine and plastics did not produce ecotoxic eluates. A relationship between zinc concentrations in eluates and their ecotoxicity was found for chars obtained from mixtures with tires. A significant reduction in ecotoxicity was found when the chars were treated with EDTA, which was due to a significant reduction in zinc in chars after EDTA washing

Salinity and Atrazine Sublethal Levels Induce Gill Cells Basolateral Membrane Phospholipids Modulation in Sea Lamprey Downstream Migrants

Conditions experienced by anadromous fishes while in freshwater may be critical to their subsequent survival in the sea. During the trophic migration to the ocean, juveniles of sea lamprey (Petromyzon marinus L.) are exposed to several stress factors, including different types of pollutants. We analyzed gill histopathological biomarkers, characterized the lipid profile of the basolateral membrane (BLM) of gill cells, and determined NKA activity, in order to evaluate if BLM lipid profile system plays a part in modulation of NKA activity and may be involved in the successful acclimation of sea lamprey juveniles during downstream migration

Potential of supercritical fluid myrtle extracts as an active ingredient and co-preservative for cosmetic and topical pharmaceutical applications

Funding Information: The authors gratefully acknowledge the support of Fundação para a Ciência e a Tecnologia ( FCT ) through the grants UIDB/04567/2020 and UIDP/04567/2020 to CBIOS , UIDB/04028/2020 to CERENA and UIDP/04077/2020 to MEtRICs . Publisher Copyright: © 2022 Elsevier B.V.This study investigated the applications of a myrtle extract obtained by supercritical fluid extraction (SFE), a technique considered environmentally friendly, as a possible antimicrobial ingredient in cosmetic and pharmaceutical formulations. The supercritical fluid extract was obtained at 230 bar and 45 °C, for 2 h, with a flow of CO2 of 0.3 kg h−1. A cosolvent (ethanol) was also used, with a flow 0.09 kg h−1. The extracts thus obtained were tested against seven Gram-positive bacteria and one yeast using the well diffusion and the broth dilution techniques. The results showed that the myrtle extract exhibits good antibacterial activity against all the bacteria strains studied and is superior to most of those obtained by conventional extraction methods. Antifungal activity was also present but at a lesser extent. Cell viability studies were carried out by exposing HaCat cells to a range of extract concentrations, from 0.1 μg/mL up to 60 μg/mL for 24 h, using the MTT assay. The Salmonella mutagenicity assay was applied to evaluate the mutagenicity and antimutagenicity of the extract. The results obtained suggest that the myrtle extract obtained using a green solvent, supercritical CO2, is safe and could reduce the genotoxic damage induced by reactive oxygen species (ROSs).publishersversionpublishe

Development and Optimization of an Online SPE-HPLC-FD Method for Quantification of Fluoroquinolones in Wastewater Effluents

Fluoroquinolones are antimicrobial agents widely found in environmental matrices and extensively studied due to their persistence and implications for multiresistant bacteria. The presence of fluoroquinolones in the environment is mainly due to the incapability of wastewater treatment plants (WWTPs) to completely remove those compounds. The amount of fluoroquinolones released through effluents depends on the type of treatment used by the WWTPs. So, accurate analytical methods to quantify those compounds on WWTPs process and in effluents are crucial. Solid phase extraction (SPE) coupled to liquid chromatography is a straightforward technique that provides analyte extraction, cleanup, separation and detection while providing a good reproducibility and efficiency. The purpose of this work was the establishment of a novel method for quantification of Ofloxacin, Norfloxacin, Ciprofloxacin and Moxifloxacin on WWTPs effluents using on-line SPE. Samples were injected directly on a restricted access material column LichroCart 25-4 Lichrospher® RP-18 ADS (25 μm) and then transferred to an analytical column Luna PFP (2) (150 x 4.6 mm ID, 100 Å, 3 μm) for separation in isocratic mode with a mixture of 0.1% triethylamine in water (acidified to pH = 2.2 with trifluoroacetic acid) and ethanol as mobile phase; column oven was set at 45ºC. The detection was performed by fluorescence with an excitation wavelength of 290 nm and an emission wavelength of 460 nm. The injection volume of 100 μL of previous preconcentrated sample was compared with larger volume injection of only filtered effluent samples. The study was conducted with effluent samples collected from a municipal WWTP in the north of Portugal

Toxin profile of two Gymnodinium catenatum strains from Iberian Coastal Waters

Gymnodinium catenatum has been the main species responsible for paralytic shellfish poisoning events along the Portuguese coast (Iberian Peninsula), causing bans on bivalve harvesting that result in huge economic losses. This work presents the characterization of two novel isolates of G. catenatum regarding their growth and toxin profiles. Laboratory growth experiments revealed that, although low growth rates were obtained during cultivation, the cell yields were high compared to those reported in the literature. Evaluation of the toxin profiles, by HPLC-FLD, essentially confirmed the typical composition of toxins of this regional population (Iberian Peninsula), namely, the absence or low representation of the toxins dcNEO, GTX1,4 and NEO and a higher ratio of the toxins C1,2, GTX6 and GTX5. However, the percentage of the identified toxins varied among the strains of this study (under the same isolation, growth, and analysis conditions), and also differed from that of other strains described in the literature. Interestingly, we found a comparatively high abundance of dcSTX in both strains, relative to the other toxins, and an unquantifiable amount of C3,4 toxins. In addition to the geographic relationship between toxin profiles, chemical conversions among toxins may explain some differences encountered in the toxin profiles of G. catenatum strains.info:eu-repo/semantics/publishedVersio

SUB-LETHAL EFFECTS OF EXPOSURE TO ATRAZINE IN GILL CELLS OF SEA LAMPREY DOWNSTREAM MIGRANTS

In Portugal, atrazine (ATZ) was one of the most widely used herbicides in agriculture, and despite prohibited since 2007, it still continued to be detected in the surface and ground waters. Recent research demonstrated that the conditions experienced by anadromous fishes, while in freshwater, may be critical to their subsequent fitness and survival in the sea. Several studies established a decline in wild populations, most probably caused by a reduction in recruitment related with pollution. In the case of sea lamprey (Petromyzon marinus) trophic migration to the ocean, expose fish to several stress factors, including chemical stress. Thus, it is crucial to assess the effects of sub-lethal exposure to ATZ and predict potential consequences to juveniles of sea lamprey

Removal of Paracetamol and Cu2+ from Water by Using Porous Carbons Derived from Agrowastes

Publisher Copyright: © 2023 by the authors.Dende and babassu coconuts are largely used in tropical countries, namely in Brazil, for the extraction of oils from kernels. The remaining biowastes are industrially processed to produce porous carbons (PCs). PCs derived from dende and babassu biowastes and produced at an industrial scale have been characterized by textural, chemical, and ecotoxicological parameters. A commercial activated carbon (CC) of mineral origin has been used as a benchmarking material. Although the CC sample presented a higher surface area (SBET = 1083 m2/g), the PCs derived from the biowastes were richer in micropores (Vmicro = 0.25–0.26 cm3/g), while the CC carbon presented wider pore size distribution with a higher mesopore volume (Vmeso = 0.41 cm3/g). All the adsorbents used in this work have shown a non-acute ecotoxic behavior for the bacterium Vibrio fischeri (EC50-30 min > 99% v/v). The adsorbents have been tested for paracetamol and Cu2+ adsorption in mono- and bicomponent solutions. The uptake capacities of paracetamol (qe, 98–123 mg g−1) and Cu2+ (qe, 15–18 mg g−1) from monocomponent solutions were similar to the ones obtained in the bicomponent solutions, indicating no competition or cooperative effects but a site-specific adsorption. This finding represents an advantage for the removal of these adsorbates when present in the same solution as they can be adsorbed under similar rates as in the single systems. Paracetamol adsorption was related to micropore filling, π-π interactions, and H-bonding, whereas Cu2+ removal was attributed to the cation exchange mechanism and complexation to the hydroxyl groups at the carbons’ surface.publishersversionpublishe

Polyphenol oxidase activity and colour changes of ‘Starking’ Apple cubes coated with alginate and dehydrated with air

The objective was to study the effect of alginate coating on polyphenol oxidase (PPO) activity and colour of ‘Starking’ apple cubes during dehydration with hot air. Apple cubes were dehydrated at 20°C, 35°C or 40°C, with a parallel air-flow. Analysis of PPO activity, colour (L*, a*, b*) and dry matter were performed along the dehydration process at each temperature. All samples presented a peak in relative PPO activity in the beginning of the drying. Exponential models fitted well the experimental data after the peak. Cubes without coating presented lower PPO activity, suggesting lower browning than coated samples throughout the dehydration process, for all temperatures. Better results for coated samples were obtained with a perpendicular airflow drying at 40°C, after dipping the whole apple in water at 60°C for 10 minutes. In order to prevent coated samples from browning, drying by perpendicular airflow preceded by a thermal treatment of the whole apple is required.info:eu-repo/semantics/publishedVersio

Probable Person-to-Person Transmission of Legionnaires’ Disease

Correspondence to the Editor.Legionnaires’ disease is an often severe form of pneumonia that is typically acquired by susceptible persons (e.g., elderly persons and smokers) through inhalation of aerosols that contain legionella species.1-4 A cluster of cases of this disease occurred in Vila Franca de Xira, Portugal, in 2014