Application of Biochar Functionalized with Layered Double Hydroxides: Improved Plant Growth Performance after Use as Phosphate Adsorbent

The objective of this study was to verify the feasibility of using biochar, functionalized with layered double hydroxides, as a fertilizer after its use in phosphate treatment (P-BC-LDHs). It was conducted with several levels of P-BC-LDHs using seed germination and early growth assays of lettuce (Lactuca sativa L.). The application of P-BC-LDHs resulted in successful seedling emergence, with an excellent germination capacity of over 96% for all treatments. However, compared to the controls, P-BC-LDHs did not provide favorable seedling traits. In contrast, in the latter experiments, lettuce cultivated under mixtures with P-BC-LDHs, particularly at an application rate of 2.5% (w/w), displayed superior growth quality to those under non-treated conditions. The length of lettuce shoots and roots from this optimal dosage were increased by at least 24% compared to untreated samples. A 17% reduction in biomass yield was observed for the samples from non-supplemented substrates. The nutrient release profiles showed that P-BC-LDHs were capable of slowly supplying phosphorus, thereby increasing the long-term nutrient availability for plants. The findings reported here provide important insights into these materials and confirm that P-BC-LDHs can be used for agricultural purposes after phosphate remediation applications. The results of this study provide constructive information to facilitate the implementation of biochar-based LDH composites for sustainable phosphate removal and recovery.

Undeclared (Poly)phosphates Detection in Food of Animal Origin as a Potential Tool toward Fraud Prevention

(Poly)phosphates are approved as water-preserving and emulsifying agents that improve the appearance and consistency of many food products. The labelling of added (poly)phosphates is essential for protecting vulnerable population groups and to prevent unfair trade practices resulting in economic fraud. The problems with (poly)phosphates’ utilisation concerns both analytical and legislative issues, such as: (1) their straightforward detection; (2) excessive addition altering freshness perception and misleading consumers; (3) uncontrolled usage increasing foodstuff weight; (4) application in products where they are not permitted; and (5) no indication on the label. Bearing all these issues in mind, the main purpose of this study was the quantification and screening of the (poly)phosphates profile in meat, marine and dairy products (160 samples), of which 43 were without declared (poly)phosphate treatment. Analysis was completed by high-performance ion-exchange chromatography either with conductometric detection or coupled to Q-Exactive Orbitrap high-resolution mass spectrometry. Although the (poly)phosphates profiles varied greatly according to species and processing type, the following criteria for detection of illicit treatment were established: high orthophosphate level, quantified short-chain (poly)phosphate anions and the presence of long-chain forms. In conclusion, the instrumental platforms used in this study can be recommended to inspection bodies as reliable methods for the detection of food adulteration with (poly)phosphates.

Toceranib phosphate-associated nephrotic syndrome in a dog: a case report

Background Nephrotic syndrome (NS) is rare in dogs and is characterized by concurrent clinical findings of proteinuria, hyperlipidemia, hypoalbuminemia, and edema. NS has been reported in humans receiving tyrosine kinase inhibitors (TKI) and in dogs receiving masitinib. This is the first report of NS in a dog receiving toceranib phosphate. Case presentation An 8-year-old, female, spayed Labrador retriever was diagnosed with a 10 cm mast cell tumor on the left lateral abdomen. After completion of a 12-week vinblastine and prednisone protocol, she began treatment with toceranib phosphate (2.6 mg/kg by mouth, every other day). Proteinuria was documented prior to starting toceranib. On day 426 after diagnosis (day 328 of toceranib phosphate treatment), the dog was evaluated for diarrhea, lethargy and anorexia. On physical examination, dependent edema was noted on the ventral chest and abdomen, and sterile neutrophilic inflammation was aspirated from a 2.3 cm splenic nodule. The following laboratory values were reported: albumin < 1.5 g/dL; cholesterol 378 mg/dl and urine protein to creatinine ratio of 3.79. The patient was diagnosed with NS, and treatment with toceranib phosphate was discontinued. Low-dose aspirin was started in addition to an increased dosage of enalapril (0.47 mg/kg q12hr). No other therapy was instituted. The dog improved clinically, and laboratory values returned to near normal over the 8-week follow-up. She was euthanized 1399 days after discontinuing toceranib phosphate with progressive disease. Conclusions Nephrotic syndrome is a potential adverse event associated with the drug toceranib phosphate which may be reversible with discontinuation of treatment. Careful monitoring of urine protein, serum biochemistry, blood pressure and patient weight is advisable during treatment with toceranib phosphate.

Phosphorus Release and Adsorption Properties of Polyurethane–Biochar Crosslinked Material as a Filter Additive in Bioretention Systems

Bioretention systems are frequently employed in stormwater treatment to reduce phosphorus pollution and prevent eutrophication. To enhance their efficiency, filter additives are required but the currently used traditional materials cannot meet the primary requirements of excellent hydraulic properties as well as outstanding release and adsorption capacities at the same time. In this research, a polyurethane-biochar crosslinked material was produced by mixing the hardwood biochar (HB) with polyurethane to improve the performance of traditional filter additives. Through basic parameter tests, the saturated water content of polyurethane-biochar crosslinked material (PCB) was doubled and the permeability coefficient of PCB increased by two orders of magnitude. Due to the polyurethane, the leaching speed of phosphorus slowed down in the batching experiments and fewer metal cations leached. Moreover, PCB could adsorb 93–206 mg/kg PO43− at a typical PO43− concentration in stormwater runoff, 1.32–1.58 times more than HB, during isothermal adsorption experiments. In the simulating column experiments, weaker hydropower reduced the PO43− leaching quantities of PCB and had a stable removal rate of 93.84% in phosphate treatment. This study demonstrates the potential use of PCB as a filter additive in a bioretention system to achieve hydraulic goals and improve phosphate adsorption capacities.

Optimization of Pickling Solution for Improving the Phosphatability of Advanced High-Strength Steels

This study investigated the optimum pickling conditions for improving the phosphatability of advanced high-strength steel (AHSS) using surface analysis and electrochemical measurements. To remove the SiO2 that forms on the surface of AHSS, 30 wt.% NH4HF2 was added to the pickling solution, resulting in a significant reduction in the amount of SiO2 remaining on the surface of the AHSS. The phosphatability was improved remarkably using HNO3 concentrations higher than 13% in the pickling solution. Furthermore, phosphate crystals became finer after pickling with a HNO3-based solution rather than a HCl-based solution. Electrochemical impedance spectroscopy (EIS) data indicated that the corrosion resistance of AHSS subjected to HNO3-based pickling was higher than that of AHSS subjected to HCl-based pickling. Fluorine compounds, which were involved in the phosphate treatment process, were only formed on the surface of steel in HNO3-based solutions. The F compounds reacted with the phosphate solution to increase the pH of the bulk solution, which greatly improved the phosphatability. The phosphatability was better under HNO3-based conditions than a HCl-based condition due to the fineness of the phosphate structure and the increased surface roughness.

Selection and valorization of arbuscular mycorrhizal fungi isolated from phosphate sludge basins in promoting of citrus and carob seedlings

Accumulation of phosphate sludge (PS) generated from phosphate treatment process in the open air represent an environment risk and a problem in terms of storage capacities. The use of this by-products in agriculture, is an alternative recovery technique for the phosphate. Moreover, selection of symbionts and their inoculation into the soil whether in the nursery or at field were strongly encouraged. These inoculants were selected not only for their impact on the plant, but also for their ability to persist in the soil at the expense of the residual native microflora. This can be performed to the microorganisms which could occur in the solid sludges deriving the exploitation of phosphates in a pilot site of Khouribga area. In this context, the indigenous mycorrhizal resources have been exploited through better exploration of the local floristic diversity and then a series of mycorrhizal fungi selection and production tests have been made. The mycorrhizal complex was prepared and their effect was tested in Citrus and carob plants growth in the nursery. Two mixtures of PS were carried out: 10% (S2) and 40% (S5) for Citrus plants and 20% (S3) and 40% (S5) for carob plants. The sandy soil of Maamora forest was used as a control (S1). The results shown three dominant morphotypes were detected: Rhizophagus irregularis, Funnileformis constrictum and Scutellospora calospora. The effect of the PS with the AMF-based inoculum indicate that mycorrhizal inoculation of the substrates by a raw inoculum stimulates the growth of plants specially S2, S5 and S3 for Citrus volkameriana, Carrizo citrange and carob respectively. Based on these results, this combination between PS and mycorrhizal fungi had a great effect on Citrus and carob plant in the nursery.

Effect of phosphate treatment on interfacial properties of poplar fiber/high-density polyethylene composites

Poplar fiber was treated with phosphate solution as a modifier and then wood fiber/high-density polyethylene (HDPE) degradable composite was prepared by melt blending with HDPE. The effects of phosphate solution concentration on tensile strength and flexural strength of composites were investigated. The surface morphology of phosphate-treated poplar fibers was observed by scanning electron microscopy. The results show that the phosphate treatment increases the surface roughness of the poplar fiber, increases the strength of the single fiber, and effectively improves the mechanical adhesion to the HDPE matrix. However, when the phosphate concentration is too large, the density of the cellulose molecular chains is lowered, and the mechanical properties of the whole fiber are lowered. When the concentration of phosphate solution is 3%, the treatment time is 4 h, and the treatment temperature is 60°C, the tensile properties, bending properties, and water resistance of poplar fiber/HDPE composites are the best.

Phosphate Dosing in Drinking Water Distribution Systems Promotes Changes in Biofilm Structure and Functional Genetic Diversity

Water utilities treat drinking water by adding phosphate to prevent metal dissolution from water pipe work systems and particularly lead poisoning. Phosphate can be a limiting nutrient for microbial biofilms in DWDS, yet its effects on these microbial consortia are not well understood. This research presents results from phosphate dosing experiments using a real scale chlorinated DWDS, comparing standard phosphate concentrations of United Kingdom drinking water (1 mgP/L) with a double dose (2 mgP/L) commonly used in plumbosolvency treatment. Biofilm development during phosphate treatment experiments was monitored using a holistic approach by combining metagenomics analysis, flow cytometry and SEM characterisation. The increase of phosphate levels in drinking water, reduced biofilm cell numbers and promoted the presence of poorly distributed biofilms on inner pipe surfaces. Metagenomics analysis using genetic markers (16S rRNA and ITS2) showed that phosphate influenced biofilm community structure, particularly fungal composition. Whole metagenome sequencing showed that phosphate enrichment favoured the presence of sequencing reads associated to ATPases, ion transporters and DNA-interacting proteins, whilst reads associated to nitrogen metabolism were predominant in control samples. This research brings new knowledge regarding the influence of phosphate treatment on the composition and structure of biofilms within DWDS, and the implications that this might have for the management of these systems.

Ileal Digestibility and Total Tract Retention of Phosphorus in Inorganic Phosphates Fed to Broiler Chickens Using the Direct Method

The objective of this study was to determine and compare the phosphorus (P) utilization of inorganic phosphates fed to broiler chickens using the direct method. On day 15 of age, six hundred forty 15-day-old male Ross 308 broiler chickens (initial body weight = 399 ± 38 g) were assigned to five experimental diets with 16 birds per cage in a randomized complete block design. The experimental diets consisted of four semi-purified diets containing monocalcium phosphate, monodicalcium phosphate, dicalcium phosphate, and tricalcium phosphate as the sole P sources. Additionally, a P-free diet was prepared to measure basal endogenous P loss. Chromic oxide was added to the experimental diets as an indigestible index. Excreta were collected per cage on days 17 to 18 of age, and all birds were asphyxiated with carbon dioxide on day 19 of age for ileal digesta collection. The cage was an experimental unit, and the number of replications per each treatment was eight except for the tricalcium phosphate treatment (n = 4). There was no interaction observed between the P source and the collection site (ileal digestibility vs. total tract retention). Phosphorus utilization differed (p < 0.05) among inorganic phosphates and the ileal digestibility of P was greater (p < 0.05) than the total tract retention. In conclusion, the standardized ileal digestibility of P in inorganic phosphates ranged from 56.7% to 89.8% and ileal digestibility was greater than the total tract retention.