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In the framework of circular economy, the need of new feedstock materials for the production of alternative new products is of high priority. Biowastes such as manure, sewage sludge (biosolids, BS) and food-waste are used as raw materials for the production of biochar. The present study aims at characterizing biochars produced from three distinct biowastes (i) manure from cattle waste (manure-derived biochar; MDB), (ii) biosolids (BS) from a conventional Urban Wastewater Treatment Plant (UWTP) (biosolids-derived biochar; BDB), and (iii) spent coffee grounds (SCG)-derived biochar (SCGDB). Samples were slowly pyrolyzed in a small-scale kiln with a capacity of 20–24 kg. The samples were heated under nitrogen atmosphere at approximately 6–7 °C min−1 up to the desired temperature (550 °C) and held for 1.5h. The physicochemical characterization of biochars showed the production of alkaline materials with similarities and variations in their characteristics, which depend to the type of feedstock used. The surface area of the raw materials was considerably low (

Hairdressing personnel is daily exposed to various chemical air pollutants, and specifically to Volatile Organic Compounds (VOCs) and Particulate Matter (PM) in hair salons. This is of concern, due to the hazardous effects of these chemicals on the individual's health. Nevertheless, a limited exposure assessment of indoor air quality (IAQ) has been performed. The aim of this study was to analyze the indoor air in 5 hair salons, to assess the IAQ of the occupational exposure, and to identify the main VOCs produced or activities responsible for the respective indoor pollution. The chemical analysis took place inside the salon environment by monitoring the emitted VOCs, as well as the PM of 1, 2.5, 4, and 10 μm aerodynamic diameter. The sampling of VOCs was performed by adsorption of pollutants on Tenax TA sorbent tubes, that were subsequently analyzed using a thermal desorption unit coupled to gas chromatography/mass spectrometry (TD-GC/MS). The obtained results showed that hair products are a major source of air pollutants, as elevated concentrations of VOCs and PM are released in the working environment. Furthermore, the type and concentration of VOCs are affected by the various hair treatment activities taking place in the salons. Among the main compounds detected there was benzene, toluene, ethylbenzene, and xylenes, known as BTEX, as well as, diethyl phthalate, 1,4-dioxane, etc. More than 50 VOCs were identified (occurrence ≥60%) and 14 of them were quantified. Their average concentration levels varied from 12 μg m

Four novel fruit-derived biochars were developed: pomegranate peels (PB), prickly pear peels (PPB), carob (CB), and locust bean gum (LBGB). The feedstocks were pyrolyzed at 350 and 550 ℃ (under N2), respectively, and characterized using Scanning Electron Microscopy (SEM), Elemental Analysis (EA), Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), Brunauer–Emmett–Teller (B.E.T) analysis, and Thermogravimetric analysis (TGA). A systematic and comprehensive comparison for the adsorption of selected volatile organic compounds (VOCs) by biochar was established. Cresol, dimethyl trisulfide (DMTS), hexane, and benzene were examined as a function of contact time (30–480 min), mass (0.1–1 g), concentration levels (50–1000 ppbv), efficiency, and reusability, using the headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC–MS) method. PB 550 ℃ revealed a specific surface area of 8.3 m2 g−1, the fastest complete removal, an ideal mass of 1 g, 3-times reuse, and ∼ 99% removal of 500 ppbv benzene, cresol, DMTS, and 100 ppbv hexane.

Biochars produced from various organic waste feedstocks have lately been utilized as adsorbents for the decontamination of antibiotics-contaminated environmental matrices. The aims of the present study were a) the assessment of the adsorption capacity of three distinct derived biochars [biosolids (BDΒ), cattle manure (MDB) and spent coffee grounds (SCGDB)], applied either at a low (1 g L−1) or high (10 g L−1) dose on seven antibiotics (tetracycline, TET; erythromycin, ERY; clarithromycin, CLA; ampicillin, AMP; ofloxacin, OFL; sulfamethoxazole, SMX; trimethoprim, TMP) spiked as mixture in environmentally relevant concentration (100 μg L−1) of an aqueous solution (8.27 85%) of AMP and TMP. However, the studied biochars failed to remove OFL and SMX. The adsorption results were best fitted to the Freundlich model with the sole exception of SMX. The main responsible mechanisms for the adsorption of antibiotics included surface complexation, H-bonding, π-π electron-donor-acceptor (EDA) interactions, pore-filling effects or the simultaneous occurrence of several of these mechanisms. Overall, the results highlighted the potential utilization of BDB, MDB and SCGDB for the decontamination of antibiotics-contaminated water bodies, while promoting the circular economy strategy.

A multi-residue method for the simultaneous analysis of a wide range of pesticides in raisins using liquid and gas chromatography-tandem mass spectrometry (LC-MS/MS and GC–MS/MS) has been validated. Pesticides are extracted from raisins with ethyl acetate, followed by centrifugation. The validation study was in accordance with DG SANTE guidelines. Validation experiments have been performed in both analytical instruments. A total number of 314 pesticides were spiked in raisins of organic farming at two spiking levels for GC–MS/MS (0.025 and 0.1 mg/kg), and at three spiking levels for LC-MS/MS (0.005, 0.05, and 0.1 mg/kg) with 6 replicates at each concentration. The scope of validation included linearity, limits of quantification (LOQ), accuracy, precision, and matrix effects (%) for each pesticide. The validated method was then applied for the analysis of 37 commercial raisin samples purchased from the market. For the evaluation of the results, processing factors (PFs) have been applied to derive the amount of residue in raisins, from the maximum residue levels (MRLs) of grapes, and which in this paper will be referred as to the MRL expressed in raisins. In all conventional samples, pesticides were detected at concentrations above the LOQ. In total, 55 different pesticides were detected. All conventional samples contained multiple pesticides ranging from 2 to 24. On the other hand, samples from organic farming were found to be free of the analysed pesticides. The 13.5% of the examined samples were considered as violations. The exposure assessment for the acute risk of the violating samples indicated that no potential risk derives from the detected and approved in the EU pesticides, while the detection of not approved pesticides in the EU, and the lack of toxicological reference values for certain pesticides raise concerns for the human health, especially for children. The results of the survey study indicate the need to include processed samples, and in particular dry fruits with a high consumption rate such as raisins, in the official controls of pesticide residues in food.

The biogenic volatile organic compounds (BVOCs) emissions from cultivated plants-soil systems and N fertilization's role on these emissions are mostly unknown. This study aimed to elucidate the BVOCs emissions from a plant-soil system receiving N fertilization using Rosmarinus officinalis as a model case study. We put forward the hypothesis that N fertilization changes the BVOCs emissions patterns irrespectively the presence of Rosmarinus officinalis and that the emissions are related to N availability and bacterial abundance. To test our hypothesis, we established a microcosm (glass static chambers) study in a fully randomized design with four treatments: soil (S), soil and plant (S + P), soil and fertilizer (S + F), soil, plant, and fertilizer (S + P + F); using NH4NO3 as N source. BVOCs were sampled from the microcosms, using the static headspace sampling technique with a solid-phase microextraction (SPME) device and analyzed by gas chromatography–mass spectrometry (HS-SPME-GC–MS). Sampling occurred 1, 2, 3, 4, 7, 10, 15, 17, 22, 25, and 31 days after applying the NH4NO3 and besides BVOCs, we measured soil NH4+ and NO3− concentration as well as 16S rRNA bacterial abundance. Time drives a significant portion of the variation in the chemical diversity and quantity of the different VOCs found throughout the experiment (PERMANOVA; R2 = 0.28, p

Mining in Cyprus resulted in a significant number of abandoned sulphide mines without any rehabilitation measures. The present study aims to describe and compare the environmental parameters in three such mines with respect to water chemistry, waste dumps geochemistry, slope-topography and plant growth. The mines under study are that of Kokkinopezoula, North and South Mathiatis located at the northeast of the Troodos massif. A synopsis of the previous studies conducted for the above-mentioned mines is presented, which includes water and soil samples analyses. Although, in these areas environmental degradation is reported, there are some plants which grow naturally. Therefore, a preliminary attempt to report these plants is conducted, while remediation options presented in the literature including technosols, revegetation, phytoremediation and phytostabilization are proposed. Potential use of native plants such as Phragmites australis, Tamarix smyrnensis, Poaceae, Pinus brutia and Schoenus nigricans Poaceace could be applied for phytoremediation of the sulphide mines in Cyprus. These plants seem to have great strength at low pH values and high metal content in contaminated soils and water. The three mines under study are also compared with three other old mines located in the broader area of Cyprus; that of Xeros, Limni and Skouriotissa, which operated under similar climatic conditions. By improving abandoned mines environment with technosols, the action of native plants will be enhanced and thus work towards a successful phytoremediation treatment, resulting in the minimization of future pollutants generated by the solid waste dumps.

Vaping is promoted as a healthier alternative to smoking over the recent years, and e-cigarette (EC) users are considered to affect air quality (and thus contribute to passive smoking) much less than tobacco cigarette (TC) smokers. Here we test this hypothesis, by comparing measurements of the size distributions of particles and the levels of Volatile Organic Compounds (VOCs) exhaled by both EC and TC users. A total of 26 individuals (16 EC users and 10 TC users) provided exhaled air samples that were analyzed using the same protocol. Our measurements show that the particle number concentration emitted by both EC and TC users are comparable, but the size distributions of the particles emitted by the former exhibit significantly higher variability compared to those from the latter. The burden of the VOCs was much higher in the exhaled air of TC smokers compared to that of EC users. Although some of the VOCs measured in the exhaled air of EC users were expected, as they are used directly in the e-liquids, the collected mixtures were highly variable (i.e., varying significantly from case to case) with only 8 compounds being common among all individuals participating in the study. In contrast, we identified 65 compounds among the TC smokers that were common among the participants. Toxic compounds (e.g., benzene, acetaldehyde, toluene, xylenes, styrene, phenol, naphthalene, etc.) were also present in the exhaled air of EC users. The high variabilities observed in the size distributions of the exhaled particles and the levels of VOCs from different EC users (i.e., due to different devices, operational settings and liquids) warrants for further research in order to fully understand the main- and side-stream effects of EC use in the human micro-environment. Despite that, the high particle emissions and the presence, even at trace levels, of toxic VOCs in the exhaled air of EC users that are reported in this study, suggests that ECs should not be considered as harmless substitutes of TCs.

The barriers to racemization in C 2 D 4 Cl 2 of [Ir{Fe(P( p -tolyl) 2 )(CO) 2 (η 5 -C 5 H 5 )} 2 ] + BF 4 − and [Ir{Ru(P( p -tolyl) 2 )(CO) 2 (η 5 -C 5 H 5 )} 2 ] + BF 4 − are 17.5 and 17.8 kcal/mol respectively. Both clusters add H 2 reversibly at 1 atmosphere and room temperature. The former also forms an adduct with H 2 and CO when exposed to both gases simultaneously.

The photolysis of hexacarbonyltungsten (I) in carbon tetrachloride yields a catalytic mixture for olefin metathesis. One of the principal products of this transformation is dichlorotetracarbonyltungsten (II). Chemical preparation of II from I and chlorine was carried out. Authentic II was shown to give catalysis of 2-pentene metathesis by either heating in chlorobenzene or chloroform or irradiation in chlorobenzene or carbon tetrachloride. The Dubois report of phosgene formation in the original irradiated mixture of I in carbon tetrachloride was shown to be an artifact.