Novel nanohybrid iron (II/III) phthalocyanine-based carbon nanotubes as catalysts for organic pollutant removal: process optimization by chemometric approach.

In the present study, two iron phthalocyanine (FePc)-based nanocatalysts were synthesized and fully characterized. The carbon nanotubes (CNT) functionalized in an easy way with either Fe(II)Pc or Fe(III)Pc exhibit a very good catalytical activity. The activity in real wastewater effluent was comparable with the activity in distilled water. The procedure of modeling and optimizing with the assistance of chemometrics, utilizing design of experiments (DOE) and response surface methodology (RSM), revealed the conditions of optimum for decaying Reactive Yellow 84 on the nanocatalysts FePc_CNT. These optimal conditions included a catalyst dose of 1.70 g/L and an initial concentration (C0) of 20.0 mg/L. Under the indicated optimal conditions, the experimental findings verified that the removal efficiency was equal to Y = 98.92%, representing the highest observed value in this study. Under UVA light, after only 15 min of reaction, over 94% of dye was removed using both catalysts. The reuse experiments show that the activity of both nanohybrid material based on FePc-CNT slightly decreases over four consecutive runs. The quenching experiments show that RY84 was removed through radical pathways (O2•- and •OH) as well as non-radical pathways (1O2 and direct electron transfer).

Impaired Melatonin Secretion, Oxidative Stress and Metabolic Syndrome in Night Shift Work.

Metabolic syndrome has been associated in many studies with working in shifts. Even if the mechanistic details are not fully understood, forced sleep deprivation and exposure to light, as happens during night shifts, or irregular schedules with late or very early onset of the working program, lead to a sleep-wake rhythm misalignment, metabolic dysregulation and oxidative stress. The cyclic melatonin secretion is regulated by the hypothalamic suprachiasmatic nuclei and light exposure. At a central level, melatonin promotes sleep and inhibits wake-signals. Beside this role, melatonin acts as an antioxidant and influences the functionality of the cardiovascular system and of different metabolic processes. This review presents data about the influence of night shifts on melatonin secretion and oxidative stress. Assembling data from epidemiological, experimental and clinical studies contributes to a better understanding of the pathological links between chronodisruption and the metabolic syndrome related to working in shifts.

Club Cells-A Guardian against Occupational Hazards.

Club cells have a distinct role in the epithelial repair and defense mechanisms of the lung. After exposure to environmental pollutants, during chronic exposure, the secretion of club cells secretory protein (CCSP) decreases. Exposure to occupational hazards certainly has a role in a large number of interstitial lung diseases. According to the American Thoracic Society and the European Respiratory Society, around 40% of the all interstitial lung disease is attributed to occupational hazards. Some of them are very well characterized (pneumoconiosis, hypersensitivity pneumonitis), whereas others are consequences of acute exposure (e.g., paraquat) or persistent exposure (e.g., isocyanate). The category of vapors, gases, dusts, and fumes (VGDF) has been proven to produce subclinical modifications. The inflammation and altered repair process resulting from the exposure to occupational respiratory hazards create vicious loops of cooperation between epithelial cells, mesenchymal cells, innate defense mechanisms, and immune cells. The secretions of club cells modulate the communication between macrophages, epithelial cells, and fibroblasts mitigating the inflammation and/or reducing the fibrotic process. In this review, we describe the mechanisms by which club cells contribute to the development of interstitial lung diseases and the potential role for club cells as biomarkers for occupational-related fibrosis.

Advanced removal of Reactive Yellow 84 azo dye using functionalised amorphous calcium carbonates as adsorbent.

Two environmentally friendly organics (ethylenediaminetetraacetic acid, EDTA and its easier biodegradabe isomer, ethylenediamine-N, N'-disuccinic acid, EDDS) were used to dope calcium carbonate (CC) nanoparticles intending to increase their adsorptive properties and evaluate adsorption performance (uptake capacity and removal efficiency) for the persistent Reactive Yellow 84 azo dye. Easily synthesized nanomaterials were fully characterized (morphology and size, mineralogy, organic content, surface area, pore size and hydrodynamic diameter). RY84 removal was performed using two consecutive processes: photodegradation after adsorption. The CC-EDTA particles were most efficient for dye removal as compared to the plain and CC-EDDS particles. Adsorption kinetics and isotherms were considered for the CC-EDTA system. 99% removal occurred via adsorption on 1 g/L of adsorbent at 5 mg/L dye concentration and pH of 8 and it decreased to 48% at 60 mg/L. Maximum uptake capacity as described by Langmuir is 39.53 mg/g. As post-adsorption, under UVA irradiation, in the presence of 40 mmol/L H2O2, at dye concentration of 10 mg/L the highest degradation was 49.11%. Substantial decrease of adsorption (ca. 4 times) and photodegradation (ca. 5 times) efficiencies were observed in wastewater effluent as compared to distilled water. The results have important implications to wastewater treatments and appropriate decisions making for the choice of treatment process, process optimization and scaling up to pilot and industrial levels.

Spatial Distribution of Minor Elements in the Tazlau River Sediments: Source Identification and Evaluation of Ecological Risk.

Minor elements received more attention in recent years due to their contamination susceptibility and environmental impact. Surface sediment samples were collected from 29 sites and total contents of eight minor elements (Cr, Co, Ni, Cu, Zn, As, Cd, and Pb) were investigated in order to determine the geostatistical distribution and to predict ecological implications. The relationship between metals and ecological implications was analyzed by using the geochemical normalization approach and ecological prediction indicators such as the enrichment factor (EF), the contamination degree (CD), the environmental toxicity quotient (ETQ), and the health risk assessment. Based on the studied toxic metals, it was observed that the most toxic element in Tazlau River sediments is Cr. The assessment results of carcinogenic and non-carcinogenic risks via dermal contact indicate that the study area shows no human health risk. The correlation matrix and principal component analysis (PCA) provide an overview of the major sources, anthropogenic versus geogenic, where Cr and Cd mainly originate from anthropogenic sources, while Pb is derived from a geogenic source. The approaches used in this study will provide a baseline regarding the accumulation of minor elements in the sediment and will be useful for other studies to easily identify the major contaminates and to estimate the health human risk.

Efflorescent sulfates from Baia Sprie mining area (Romania)--Acid mine drainage and climatological approach.

The Baia Sprie epithermal system, a well-known deposit for its impressive mineralogical associations, shows the proper conditions for acid mine drainage and can be considered a general example for affected mining areas around the globe. Efflorescent samples from the abandoned open pit Minei Hill have been analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman and near-infrared (NIR) spectrometry. The identified phases represent mostly iron sulfates with different hydration degrees (szomolnokite, rozenite, melanterite, coquimbite, ferricopiapite), Zn and Al sulfates (gunningite, alunogen, halotrichite). The samples were heated at different temperatures in order to establish the phase transformations among the studied sulfates. The dehydration temperatures and intermediate phases upon decomposition were successfully identified for each of mineral phases. Gunningite was the single sulfate that showed no transformations during the heating experiment. All the other sulfates started to dehydrate within the 30-90 °C temperature range. The acid mine drainage is the main cause for sulfates formation, triggered by pyrite oxidation as the major source for the abundant iron sulfates. Based on the dehydration temperatures, the climatological interpretation indicated that melanterite formation and long-term presence is related to continental and temperate climates. Coquimbite and rozenite are attributed also to the dry arid/semi-arid areas, in addition to the above mentioned ones. The more stable sulfates, alunogen, halotrichite, szomolnokite, ferricopiapite and gunningite, can form and persists in all climate regimes, from dry continental to even tropical humid.