Biosolid, i.e., dehydrated sludge from effluent treatment stations, has been progressively used as an agricultural fertilizer due to its high organic matter and nutrient contents. Elephant grass (Cenchrus purpureus (Schumach.) Morrone) presents easy adaptation and high yields, being used for animal feeding and for energy purposes. The objective of this work was to analyze the production and bromatological parameters of elephant grass with four different doses of biosolid, one of chemical fertilizer and a control plot, with two replicates each. A field experiment was carried out using a randomized block design with three blocks, totaling 18 plots, which received biosolid fertilization at 1×, 2×, 4×, and 8× the levels recommended by the Brazilian National Environment Council, along with conventional chemical fertilization and no fertilization, all under similar drip irrigation. Tukey’s test indicated a significant difference at p < 0.01 for total production in the first cut and acid detergent fiber in the second cut. At p < 0.05, significant differences were detected for total nitrogen and total protein in the first cut. The elephant grass yield under “1× biosolid” was similar to that reached with chemical fertilization. Physical and bromatological characteristics indicated potential use as animal feed and energy source. For doses higher than specified by Brazilian standards (2×, 4×, and 8×), further studies are required to verify possible contamination from heavy metals, pathogenic microorganisms, and n.

Bisphenol A (BPA) and reactive black 5 (RB5) dye are among the most persistent and non-biodegradable contaminants in water which require an urgent need for the development of effective removal method. The ubiquitous existence of both contaminants could interfere with the human health and aquatic environmental balance. Photocatalytic process as one of advanced oxidation processes (AOPs) has shown high performance for degradation of organic compounds to the harmless materials under sensible condition. Therefore, this study aims to develop a visible-light-driven photocatalyst that can efficiently degrade BPA and RB5 present in household water. N-doped TiO₂ were successfully synthesized via simple and direct sol–gel method. The prepared TiO₂ nanoparticles were characterized by field emission scanning microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), and Brunauere Emmette Teller (BET) analysis. The incorporation of nitrogen in TiO₂ lattice exhibited excellent optical responses to visible region as revealed by UV–Vis–NIR spectroscopy absorption capability at 400–600 nm. The photocatalytic activity of the N-doped TiO₂ nanoparticles was measured by photocatalytic degradation of BPA and RB5 in an aqueous solution under visible-light irradiations. Degradation of BPA and RB5 was 91.3% and 89.1%, respectively after 360 min illumination. The degradation of BPA and RB5 by N-doped TiO₂ was increased up to 89.8% and 88.4%, respectively under visible-light irradiation as compared to commercial TiO₂ P25. This finding clearly shows that N-doped TiO₂ exhibits excellent photocatalytic degradation of BPA and RB5 under visible irradiation, hence have a promising potential in removing various recalcitrant contaminants for water treatment to fulfill the public need to consume clean water. Graphical Abstract ᅟ

The amount of deicing salt spread on the road during cold periods increased since the 1940s even though its impact on water quality is well-known. In France, an average of 0.75 tons of salt per kilometre is spread during a winter in order to ensure the users security. The salt is carried by runoff from the road to a retention pond. One of the role of these ponds is to reduce road pollution before runoff joins the environment. The efficiency of the Azerailles retention pond collecting road runoff was assessed regarding NaCl retention. Indeed, an increase in Mg²⁺, K⁺, Ca²⁺, and SO[Formula: see text] concentrations correlated to an increase in Cl⁻ and Na⁺ concentrations was observed. These observations were directly linked to the presence of deicing salt on the roadway. Forty-eight percent of the spread salt was collected by the retention pond during the winter maintenance period from December 2016 to April 2017. The high intensity of rainfall during this period had a strong influence on the amount of salt leached from the pond. Almost all of the deicing salt entering the basin was evacuated at the end of March (91%). The sediment analysis showed that sodium from the road flux was not retained in the sediment neither during nor after the salting period.

In consideration of the hazards associated with the presence of the textile azo-dye and their biotransformation products in the environment, the goal of this work was to study bioremediation process by the yeast strain Pichia kudriavzevii CR-Y103 related to the ability to degrade and detoxify the sulfonated Reactive Orange 16 azo-dye. In experimental conditions, the optimal inoculum/dye concentration ratio required for complete decolorization (100%) of culture medium and biomass within 24 h has been 1 g L⁻¹ yeast cell (dry weight)/50 mg L⁻¹ Reactive Orange 16. In the presence of 400 mg L⁻¹ of Reactive Orange 16 (RO16), 95% of the dye was removed after 72 h of incubation. Also, the yeast strain could decolorize other eight textile dyes (56.48–99.98% decolorization within 24 h). NADH-DCIP reductase and azo reductase activities were significantly increased (ca. 5.4 times and ca. 37 times, respectively) during the decolorization process. UV-VIS spectra, high-performance liquid chromatography (HPLC), and Fourier transform infrared spectroscopy (FTIR) analysis confirmed the presence of new biotransformation products in extracted metabolites, highlighting the partial biodegradation of the dye by the new yeast isolate. The phytotoxicity evaluation strongly supported the decreased toxicity of biodegraded products as minor inhibition on germination (%), root and shoots elongation of T. pratense L. and T. aestivum L. seedlings. Increasing of mitotic index value and decreasing the frequency of chromosomal aberrations in tested plant meristem cells treated with biodegraded products, compared with RO16 treatment (500 ppm), confirmed their slightly toxic nature. A cell viability assay also confirmed the reduced toxicity of biodegraded products on healthy monkey kidney cells (Vero cells).

The calcined layered double hydroxide (CLDH)-alginate hydrogel beads were synthesized by embedding CLDH into alginate hydrogel beads. The beads were used to remove p-nitrophenol (PNP) and p-aminophenol (PAP) from aqueous solution. The structure and composition of CLDH-alginate hydrogel beads were characterized by scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), elemental mapping, transmission electron microscope (TEM), X-ray powder diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, BET, and X-ray photoelectron spectroscopy (XPS). The adsorption kinetic, isothermal, thermodynamic properties and adsorption mechanism of PNP and PAP on CLDH-alginate hydrogel beads were studied. The results demonstrated that the adsorption kinetic data fitted the pseudo-second-order model well with the correlation coefficients (R²) of 0.9975 and 0.9995 for PNP and PAP, respectively. The isothermal data followed the Freundlich equation, and the values of R² for PNP and PAP were 0.9728 and 0.9946, respectively. The adsorption processes were feasible, spontaneous, and endothermic. The adsorption mechanism was predominated by anionic exchange and hydrogen bonding for PNP and hydrogen bonding for PAP, which was evidenced by the results of adsorption experiments, characterization of FTIR and XPS, and theoretical calculation. Furthermore, the CLDH-alginate hydrogel beads can be separated easily due to their larger particle size. This will provide convenience in practice application.

Persistent organic pollutants (POPs) immobilization in farm land is an important issue to solve the residue in crop, and char has been considered for the remediation. In here, three commercially available chars like powdered oak char (POC), granulated oak char (GOC), and rice husk char (RHC) including powdered activated carbon (PAC) were investigated for their potential to adsorb and immobilize endosulfan in the soil. The maximum adsorption capacities (mg g⁻¹) of the applied chars as POC, GOC, and RHC were 714.8, 322.6, and 181.8, respectively, and the capacity of POC was similar with PAC (713.8). In addition, the pore volume (0.138 cm³ g⁻¹) and the surface area (270.3 m² g⁻¹) of POC were over 3-fold higher than GOC and RHC. The bioconcentration factor (BCF) reducing effect of α-, β-endosulfan, and endosulfan sulfate in oriental radish (Raphanus sativus var. sativus) was investigated by amendment of three commercially available chars to the contaminated soils. The BCF of total endosulfan was 0.025 in the radish root. POC treatments effectively suppressed the endosulfan uptake (BCF 0.002). However, GOC and RHC showed little BCF reducing effect of endosulfan in radish.

This study describes application of free liquid membrane (FLM) in micro-electromembrane extraction (μ-EME) of Cr(VI) from wastewater samples. Amount of Cr(VI) was quantified by electrothermal atomic absorption spectrometry. The transportation of Cr(VI) across the FLM was explored by electrokinetic migration and ion-exchange process. FLM and acceptor solution types, pH of donor and acceptor solutions, applied electrical potential, as well as FLM thickness were optimized. Presence of an anion exchange carrier (methyl trialkyl-ammonium chloride, Aliquat 336) in FLM facilitated Cr(VI) transportation. The best performance was observed for 1-octanol (containing 5% Aliquat 336) with thickness of 1 mm used as FLM, under applied electrical potential of 75 V, when 0.5 M NaClO₄ and 0.1 M HCl were used as the acceptor and donor phases, respectively; and the extraction time was set to 5 min. Linearity was obtained in the working range of 0.5–14.0 ng mL⁻¹ Cr(VI) (R² > 0.98). The calculated limit of detection was below 0.06 ng mL⁻¹. Application of this method to wastewater samples showed that relative recoveries of the spiked Cr(VI) in the samples were in the range of 73.8–85.1%, based on the standard addition method.

Recycled tires are often shredded for use in a variety of consumer-related products. The rubber so used may contain a number of compounds known to be deleterious to human and environmental health. We obtained nine samples of shredded tire material sold over the counter to the general public for home use, as well as six samples used for infill in synthetic turf athletic fields. After thorough cleaning and grinding, samples were extracted with either organic solvent (dichloromethane), strong acid, or simulated acid rain, or allowed to degas passively. Compounds released by these multiple methods were then identified, and in some cases quantified. Solvent extraction yielded 92 separate compounds, of which only about half have been tested for human health effects. Of these, nine are known carcinogens and another 20 are recognized irritants, including respiratory irritants that may complicate asthma. Strong acid extraction released measurable amounts of Pb and Cd and relatively large amounts of Zn. These three metals were specifically targeted for analysis, and others may be present as well, but were unmeasured. Simulated acid rain extracted only Zn in significant quantities. Passive volatilization yielded detectable amounts of 11 compounds. Results demonstrate that recycled tire materials contain and can release a wide variety of substances known to be toxic, and caution would argue against their use where human exposure is likely.

Soil proteomics, the large-scale characterization of the entire protein complement in soils, provides a promising approach for deciphering the role of microbial functioning in terrestrial ecosystems. However, the extraction of soil proteins in sufficient quantities and of adequate purity remains a challenging task mainly due to the co-extraction of interfering humic substances. Up to now, the treatment of soil extracts with liquid phenol has been the “gold standard” for reducing humics, while the NoviPure cleanup kit was recently launched as a non-toxic approach. The present study describes an alternative method for delivering high-purity proteins based on humic coagulation with trivalent aluminum ions (Al³⁺). Various experimental parameters were optimized individually in order to maximize protein yield and diminish co-extracted humics. The optimized method was applied on a set of soil samples with diverse physicochemical characteristics and a comparison with the other two techniques was conducted. The amount of residual humics resulting from Al³⁺-based method was 26 and 35% higher than that from phenol treatment and NoviPure Kit, respectively, but these differences were of marginal statistical significance. With regard to extracted proteins, the average yields of the three methods were comparable, without showing any statistically significant differences. Overall, humic coagulation with Al³⁺ offers comparable cleanup performance in terms of protein yield and purity, but it is less toxic and less complex than the phenol-partitioning method, whereas it is far less expensive than the NoviPure Kit. The new technique is expected to facilitate the implementation of proteomic studies in soils.

The concentrations of rare earth elements (REEs) were determined by ICP-MS in feed for farm animals in three regions of Northwestern Italy. This is the first study aimed at defining the levels and patterns of REEs in feed for different animal species. REEs are in fact emerging as contaminants worldwide, following their applications in industry, technology, medicine, and agriculture. Moreover, in 2016, the first REE-based feed additive—a zootechnical additive for weaned piglets—was authorized in the EU. Therefore, information about the natural content of REEs in animal feed of vegetal origin is required to evaluate the potential use of REEs as a growth promoter. There was a high variability in the REEs content of the animal feed in three different Italian regions, and REEs content varied according to the different animal species for which the feed was intended. Concentrations of light REE (LREE) were higher than those of heavy REE (HREE) in each feed typology. Raw materials were shown to have higher ΣREE concentrations (mean concentration 2.4 mg kg⁻¹) than complete or complementary feed. Considering the animal species, mean ΣREE concentrations were as follows: horse feed (2.7 mg kg⁻¹) > poultry feed > bovine feed > swine feed (0.61 mg kg⁻¹). REE levels in feed were in line with values available in the literature on vegetables; thus, REE concentrations in feed do not constitute a concern for animal health.