Toxicity bioassay of waste cooking oil-based biodiesel on marine microalgae

The world biodiesel production is increasing at a rapid rate. Despite its perceived safety for the environment, more detailed toxicity studies are mandatory, especially in the field of aquatic toxicology. While considerable attention has been paid to biodiesel combustion emissions, the toxicity of biodiesel in the aquatic environment has been poorly understood. In our study, we used an algae culture growth-inhibition test (OECD 201) for the comparison of the toxicity of B100 (pure biodiesel), produced by methanol transesterification of waste cooking oil (yellow grease), B0 (petroleum diesel fuel) and B20 (diesel-biodiesel blended of 20% biodiesel and 80% petroleum diesel fuel by volume). Two marine diatoms Attheya ussuriensis and Chaetoceros muelleri, the red algae Porphyridium purpureum and Raphidophyte Heterosigma akashiwo were employed as the aquatic test organisms. A sample of biodiesel from waste cooking oil without dilution with petroleum diesel (B100) showed the highest level of toxicity for the microalgae A. ussuriensis, C. muelleri and H. akashiwo, compared to hexane, methanol, petroleum diesel (B0) and diluted sample (B20). The acute EC50 in the growth-inhibition test (96 h exposure) of B100 for the four species was in the range of 3.75–23.95 g/L whereas the chronic toxicity EC50 (7d exposure) was in the range of 0.42–16.09 g/L

Identification of cement in atmospheric particulate matter using the hybrid method of laser diffraction analysis and Raman spectroscopy

Environmental science; Atmospheric science; Ecology; Environmental chemistry; Environmental pollution; Atmospheric particulate matter, Laser diffraction analysis, PM10, Raman spectroscop

Characterization of fume particles generated during arc welding with various covered electrodes

Abstract Arc welding operations are considered to be risky procedures by generating hazardous welding fume for human health. This study focuses on the key characteristics, as well as dispersion models, of welding fumes within a work zone. Commercial and widely used types of electrodes with various types of covering (rutile, basic, acidic and rutile-cellulose) were used in a series of experiments on arc welding operations, under 100 and 150 amps of electric current. According to the results of this study, maximum levels of pollution with particles of PM10 fraction occur in the workspace during arc welding operations. Disregarding the types of electrodes used, the 3D models of dispersion of the РМ10 particles at the floor plane exhibit corrugated morphologies while also demonstrate high concentrations of the РМ10 particles at distances 0–3 m and 4–5 m from the emission source. The morphology of these particles is represented by solid and hollow spheres, ‘nucleus-shell’ structures, perforated spheres, sharp-edged plates, agglomerates of the tree-like (coral) shape. At last the bifractional mechanism of fume particle formation for this type of electrodes is also shown and described. In this article results are reported, which demonstrate the hazards of the arc welding process for human health. The results of the characterization of WFs reported improve our understanding of risks that these operations pose to human health and may strengthen the need for their control and mitigation

NEUROSOME: a multidisciplinary training network to explore the neurodevelopmental and neurological exposome

On the basis of existing epidemiological data, the effect of neurotoxic metals (mercury, methylmercury, lead, manganese, cadmium), pesticides (organophosphates, pyrethroids) and flame retardants (brominated and organophosphate) on the neuropsychological development of exposed children appears to be variable among individuals. The extent to which the observed differences could be explained by genetic vulnerability or co-exposure to more environmental chemicals is still unclear. Although environmental health literature is rich with knowledge on the potential individual steps linking environmental contamination to disease, there is a lack of established causality for developing the respective Adverse Outcome Pathways (AOPs), especially taking into account cumulative exposure, where different mechanisms of toxicity are involved, interacting between them at different levels of biological organization. Furthermore, the brain, the target organ of neurotoxicants, it is not accessible if not using highly invasive or extremely costly (e.g. neuroimaging) methods. Research is needed to identify a set of peripheral accessible markers of susceptibility, vulnerability and effects, able to predict the neuropsychological/neurological outcome. NEUROSOME is an Innovative Training Networks funded in 2017 within H2020 Marie Sklodowska-Curie Actions. The main objective of the NEUROSOME project is the development of an integrated model based on real human biomonitoring data (HBM) to identify causal associations between early environmental exposures, the human genome, and the risk of neurodevelopmental disorders and neurodegenerative diseases. In particular, the project is based on the evaluation and re-analysis of biological samples collected in existing birth cohorts (PHIME, INMA, PROBE) and in the context of a cross-Mediterranean cohort study set up specifically within NEUROSOME. The project is focused on exposure to mixtures of heavy metals and organic compounds (phthalates, plasticizers, pyrethroids, organophosphate pesticides and brominated and organophosphate flame retardants), but will also consider the role of modulation and the synergistic or additive effects of other intrinsic (such as genetic susceptibility) and extrinsic (such as diet and socio-economic status) environmental stressors. This requires the synthesis among different scientific disciplines, including environmental and exposure modelling, recent advances in toxicology (including in vitro, in vivo and in silico aspects) with a special focus on omics technologies and bioinformatics, as well as environmental epidemiology, taking stock of gene- and exposome-wide associations. The NEUROSOME objectives are pursued through an interdisciplinary network aimed at developing new knowledge and training a new generation of young European researchers on the most current issues of the relationship between the environment and health. Fifteen selected Early Stage Researchers will move between participating institutions to integrate their transdisciplinary skills and learn the different research approaches, from in silico models to human biomonitoring. A preliminary set of results collected in the first year of the project will be presented: they include collection of HBM and outcome data from the relevant population studies, transcriptomics and metabolomic signatures linked to the neurodevelopmental phenotype in biosamples, the establishment of in vitro and in vivo models of exposure to environmentally relevant chemical mixtures and generic lifetime PBBK model incorporating mixtures interaction to integrate exposure data and modelling output with HBM data

Stabilization of formamidinium lead triiodide alpha-phase with isopropylammonium chloride for perovskite solar cells

The operational stability of formamidinium lead triiodide solar cells varies with the fabrication method of the perovskite layer. Now Park et al. find that isopropylammonium stabilizes the perovskite structure and leads to solar cells with 2,000-h stability under constant illumination. Formamidinium lead triiodide (FAPbI(3)) perovskite solar cells (PSCs) are mainly fabricated by sequentially coating lead iodide and formamidinium iodide, or by coating a solution in which all components are dissolved in one solvent (one-pot process). The PSCs produced by both processes exhibited similar efficiencies; however, their long-term stabilities were notably different. We concluded that the major reason for this behaviour is the stabilization of the alpha-FAPbI(3) phase by isopropylammonium cations produced by the chemical reaction between isopropyl alcohol, used as solvent, and methylammonium chloride, added during the process. On this basis, we fabricated PSCs by adding isopropylammonium chloride to the perovskite precursor solution for the one-pot process and achieved a certified power conversion efficiency of 23.9%. Long-term operational current density-voltage measurements (one sweep every 84 min under 1-Sun irradiation in nitrogen atmosphere) showed that the as-fabricated device with an initial efficiency of approximately 20% recorded an efficiency of about 23% after 1,000 h that gradually degraded to about 22% after an additional 1,000 h