Toxic Hazards Research Articles

Phytochemical and Heavy Metal Screening of Fura da Nono, Ciklavit®, Katoka Mixtures®, and Yoyo Bitters®

Background: Evaluation of the phytochemicals and heavy metals contained in four commonly consumed beverage and herbal products in Nigeria, was investigated. This was to ascertain the health benefits as well as potential for toxicity that may be associated with the consumption of these products. Methods: The samples studied are Fura da Nono, Ciklavit®, Katoka Mixtures® and Yoyo Bitters®. The phytochemical screening of each product was done using standard procedures. The heavy metals screening was done using Agilent®720 Inductively Coupled Plasma -Optical Emission Spectroscopy machine (ICP-OES). The Hazard quotient and Index were assessed using appropriate equations in line with United States Environmental ProtectionAgency (USEPA). Results: All phytochemicals tested were found in Fura da Nono except Steroids and Terpenoids.Also, all the tested phytochemicals were detected in Ciklavit® except Alkaloids and Phlobatannins. Both Katoka Mixtures® and Yoyo Bitters® contained all other phytochemicals except Phlobatannins. Quantitatively, Fura da Nono was high in Cardiac glycosides, and Ciklavit® was found to be high in Flavonoid content. Both Katoka Mixtures® and Yoyo Bitters® are high in Phenols. The results of the heavy metal analysis revealed different concentrations (ppm) of arsenic, mercury, lead, cadmium, zinc, manganese, copper and nickel in the four products. Arsenic was not detected only in Fura da Nono. The heavy metal concentrations obtained were all within WHO maximum permissible limits. Further analysis for potential non-carcinogenic health risk using Hazard quotient on each of the four toxic heavy metals (arsenic, mercury, lead and cadmium) and Hazard Index (HI) on the same toxic heavy metals revealed that by the United States Environmental ProtectionAgency (USEPA) threshold value of HI ≤1, Yoyo Bitters® (0.4684) and Ciklavit® (0.7870) had the lower and safer values for combined heavy metal risk while Katoka Mixtures® (0.9908) and Fura da Nono (1.4144) had the highest. Conclusion: The phytochemical screening of the investigated products showed that the commonly consumed food drink and herbal products, are rich in phytochemicals. Even though the heavy metal screening indicates a fairly positive safety margin for three of the products. Caution should therefore be exercised in the use of these products.

Retraction Note: Approaches to reducing the toxic exposure hazard on the sheep population.

Retraction Note: Approaches to reducing the toxic exposure hazard on the sheep population.

Polydopamine-coated HKUST MOFs-based strip lateral flow immunoassay for on-site ultrasensitive detection of aflatoxin B1 in foods

Owing to the high residue in foods and severe carcinogenic and teratogenic effects to human health of aflatoxin B1 (AFB1), it is vital to develop a reliable method for sensitive detection of AFB1. In this work, the polydopamine-coated Cu-based metal-organic framework ([email protected]) as a signal amplification marker was introduced to develop a strip lateral flow immunoassay (SLFIA) for on-site detection of AFB1 in food samples. The [email protected] was prepared by simple oxidative self-polymerization of dopamine on the surface of the HKUST. [email protected] with excellent hydrophilicity and biocompatibility allowed rapid labeling of anti-AFB1 monoclonal antibodies (mAbs) by simple physical adsorption. Under optimal conditions, [email protected] probes-based SLFIA could realize the qualitative visualization and sensitive quantitative detection by using a portable test strip reader. The detection limit for AFB1 was as low as 0.01 ng/mL with a wide concentration range of 0.05–2 ng/mL. Practical application in Maize and Lotus seed samples indicated satisfactory recoveries of 80.3–104.6%. The effectiveness and accuracy of the new SLFIA method were verified with a validated UFLC-MS/MS technique. The preparation process of [email protected] SLFIA was easy to operate with significantly improved sensitivity and stability, and could be widely used in the rapid and accurate detection of mycotoxins and other toxic hazards in foods.

Efficacy of Shilodbhidadi taila uttarabasti in the management of Pittaja mutrakricchra (cystitis) in female – An experience

Abstract: Urinary Tract Infections (UTIs) are a common cause of morbidity and have the potential to cause kidney damage. Mutrakricchra (~cystitis) is a disease of Mutravaha srotas (~urinary tract) and its symptomatology resembles more closely to cystitis which is the basic form of UTI. The injudicious use of prescribed antibiotics causes toxicity, drug resistance, and health hazards which make it difficult to manage the recurrent UTI. There is a need to search for an ideal therapy for UTI that causes least adversities. This case report provides an effective Ayurveda protocol to the existing modalities of UTI management. A 58-year-old female visited the Ayurveda outpatient department with the complaints of Adho udarashoola (~pain in the lower abdomen), Sashoola, Sadaha mutra pravritti (~painful, difficult, and burning micturition), and Atimutra pravritti (~increased frequency of micturition) with the frequency of 10–15 times/24 h for two months. After analysis, based on Ayurvedic and modern parameters, the condition was diagnosed as Pittaja mutrakricchra (~dysuria caused due to vitiation of Pitta dosha). After 60 days of management, the patient got complete relief after taking consecutive two sittings of Uttarabasti (~intraurethral douching) for eight days with an interval of one month along with Shamana chikitsa (~palliative therapy), suggesting in effective management of Pittaja mutrakricchra (~cystitis) in female through Ayurveda treatment protocols.

Natural History and Clinical/Dosimetric Determinants of Osteoradionecrosis in a Large Cohort of Head and Neck Cancer Following Curative Radiotherapy: Debunking the Myth of Decreased Rates of Osteoradionecrosis in the Modern Radiotherapy Era

Osteoradionecrosis (ORN) of the mandible is the most devastating toxicity following head and neck cancer (HNC) radiotherapy (RT). The rate of ORN occurrence has been debatable in the modern era of advanced RT. We aim to determine the natural history and time to ORN development in a large cohort of HNC. After IRB approval, we identified HNC patients treated with curative-intent RT between 2005 and 2020 at MD Anderson Cancer Center. Dental oncology notes were reviewed and all dental procedures were recorded. Available dose volume histograms (DVHs) for the segmented mandibular volumes were extracted. Based on our previously published ORN normal tissue complication probability (NTCP) model, any dental procedure pre-RT is a clinical high-risk factor and, therefore, data were coded as (high vs. low clinical risk) accordingly. We also coded the dosimetric risk factors to (high vs. low dosimetric risk) according to our published DVH thresholds (high dosimetric risk if any applies: V45≥40%, V55≥25%, and/or D30 ≥40 Gy). Finally, patients were classified to four groups according to combined clinical and dosimetric risk factors (No, clinical, dosimetric, and both). We used the Kaplan-Meier method to calculate time to ORN development and ORN-free survival. For time to ORN development, any grade ORN occurrence was coded as event and all others were censored. For ORN-free survival, death and ORN were coded as events and all others were censored. Log-rank test was used to compared curves of different risk groups. One thousand eight hundred sixty-six patients were included. Median follow-up was 38 months (range 4-162). ORN was reported in 252 patients (13.5%). The median time to ORN development was 18.5 months (range 4-145). 95 patients (37.7%) developed ORN after 2-years post-RT. The 1-, 3-, and 5-year ORN rates were 4.7%, 12.7%, and 17.8%, respectively. The 1-, 3-, and 5-year ORN-free survival were 94.3%, 85.5%, and 80.3%, respectively. There were statistically significant differences (P < 0.0001) between ORN-free survival in different clinical/dosimetric risk factors. The patients with no, clinical-only, dosimetric-only, and both clinical and dosimetric risk factors were 35%, 19%, 22%, and 24%, respectively. The 5-year ORN-free survival was 94.3%, 89.8%, 76.3%, and 69.6% for patients with no, clinical-only, dosimetric-only, and both clinical and dosimetric risk factors, respectively. The hazard-ratio (HR) of ORN development in clinical-only, dosimetric-only, and both clinical and dosimetric risk groups was 2.1, 5.4, and 7.5 compared to the no risk group (P<0.05 for all). Our findings indicate that ORN remains a remarkable toxicity hazard for HNC survivors. A prolonged surveillance time is required for the majority of HNC survivor since more than one-third of the ORN events occurred after 2-year follow-up. Patients with combined clinical and dosimetric risk factors have a staggering ORN risk profile and are proper candidates for future prophylactic pharmacotherapy clinical studies.

Desiccant Beads: A Novel Tool for Managing Pulse Beetle in Stored Chickpea

Chickpea is the most dominant pulse having a major share under area shown 65 per cent and production 72 per cent followed by lentil and field pea. Pulse beetle, Callosobruchus chinensis L. is a primary pest of stored chickpea which causes 50-60 per cent loss in seed weight and 45.5-66.3 per cent loss in protein content of the seeds (Rustamani et al., 1985) and injudicious and indiscriminate use of hazardous synthetic chemicals for preventing storage losses in chickpea may lead to human and animal health issues due to residual hazards. Therefore, the biorational management of the pulse beetle in stored chickpea has been undertaken keeping biology in mind will prevent the loss as well as protect human health hazard.The experiments on non-chemical biorational approaches like effect of desiccant beadswhich control the pulse beetle efficiently but have lesser toxicity hazards to non-target organisms and the environment was studied in the Department of Entomology, College of Agriculture, OUAT, BBSR, Odisha during 2018-2021.The results showed that desiccant beads viz., zeolite and sodium aluminium silicate impregnated with chickpea seeds in the ratio of 1:1 proved effective in suppression of the pulse beetle in chickpeaduring six months of storage.

MXene-wrapped zinc hydroxystannate nanocubes toward reducing the heat, smoke and toxicity hazards of ABS resin

MXene-wrapped zinc hydroxystannate nanocubes toward reducing the heat, smoke and toxicity hazards of ABS resin

A search towards alternative ways: replacing conventional chelation therapy against arsenic-induced female reprotoxicity: A review

long-term intake of contaminated water and poses the greatest public health threat from arsenic. Depending on the degree of exposure,its drastic effects might take years to manifest in developing skin lesions and peripheral neuropathy. Major radical changes occur withthe onset of developmental toxicity and reproductive health hazards in both sexes. Arsenic causes cellular damage by promotingoxidative stress and reactive oxygen species (ROS) production, resulting in chromosomal aberration and DNA damage. Managing thehealth risks brought on by arsenic has now become a global challenge. Available therapeutic strategy against arsenicosis is mainlyconcerned with using chelating agents that very often redistribute arsenic in the brain. This chelating treatment approach also needsa painful and invasive route that discourages affected individuals from continuing the therapy. Hence, we focused on alternative noninvasivestrategies in managing female reproductive ailments in arsenicated animals. We used different micronutrients, herbal extracts,phytochemicals, etc. The studies established that arsenic-nutrients/arsenic-phytomolecules interaction efficaciously reduced toxicitylevels by correcting the components of the s-adenosine-methionine pool (SAM) on the way of endorsing probable elimination ofarsenic from the system. Natural non-enzymatic antioxidants like vitamin C, vitamin E, and selenium were investigated against arsenictoxicity and proved to be beneficial for scavenging free radicals. These nutrients also enhance female gonadal function by regulatingovarian steroidogenesis and gonadotropin levels by controlling the brain’s biogenic amines. Phyto compounds such as curcumin,N-acetyl cysteine (NAC), arjunolic acid, extracts of green tea leaves (Camellia sinensis), pectic polysaccharide (CCPS) from bitter gourd(Momordica charantia) and functional foods such as probiotics and spirulina have been studied. These have been shown to mitigatearsenic toxicity via regulating various inflammatory markers such as NF-κB, MT-1, TNF-α, IL-6, etc. The potential benefits of these werealso shown against arsenic toxicity by upregulating Bcl-2 gene expression accompanied with suppression of pro-apoptotic genes BAX,p53 caspase-3, PARP, PCNA, AKT, etc., and eventually corrected female reproductive stress with improved fertility in arsenicated rats.Hence, these findings may pave the way for the development of a new drug as well as nutraceuticals with more effective and noninvasivetherapeutic approaches for arsenic toxicity.

ECHIDNA (Emerging CHemIcals Database for National Awareness): a framework to prioritise contaminants of emerging concern in water.

The widespread presence of contaminants of emerging concern (CEC) in surface waters, treated wastewater and drinking water is an ongoing issue for the water industry. The absence of regulatory guidance and limited occurrence, toxicity and removal data are defining criteria of CEC and make it difficult to prioritise which CEC pose the greatest risk. The online Emerging CHemIcals Database for National Awareness (ECHIDNA) aims to classify and prioritise CEC based on their potential risk, with the information presented in an easily accessible and intuitive manner. A candidate list of almost 1,800 potential CEC, including pesticides, pharmaceuticals and industrial compounds, was compiled using both Australian and international resources. These were ranked based on in silico assessment of their persistent, bioaccumulative and toxic (PBT) properties, as well as potential chronic toxicity hazard, yielding 247 CEC for further prioritisation. Risk Quotients (RQ) identified between 5 and 87 CEC posing a risk to human and ecosystem health, respectively, across drinking water, surface water, treated wastewater and raw wastewater. While the ability of the water industry to effectively prioritise CEC is limited by candidate identification and data availability, ECHIDNA can provide valuable information for better decision-making surrounding CEC management.

Understanding How Cationic Polymers' Properties Inform Toxic or Immunogenic Responses via Parametric Analysis.

Cationic polymers are widely used materials in diverse biotechnologies. Subtle variations in these polymers' properties can change them from exceptional delivery agents to toxic inflammatory hazards. Conventional screening strategies optimize for function in a specific application rather than observing how underlying polymer-cell interactions emerge from polymers' properties. An alternative approach is to map basic underlying responses, such as immunogenicity or toxicity, as a function of basic physicochemical parameters to inform the design of materials for a breadth of applications. To demonstrate the potential of this approach, we synthesized 107 polymers varied in charge, hydrophobicity, and molecular weight. We then screened this library for cytotoxic behavior and immunogenic responses to map how these physicochemical properties inform polymer-cell interactions. We identify three compositional regions of interest and use confocal microscopy to uncover the mechanisms behind the observed responses. Finally, immunogenic activity is confirmed in vivo. Highly cationic polymers disrupted the cellular plasma membrane to induce a toxic phenotype, while high molecular weight, hydrophobic polymers were uptaken by active transport to induce NLRP3 inflammasome activation, an immunogenic phenotype. Tertiary amine- and triethylene glycol-containing polymers did not invoke immunogenic or toxic responses. The framework described herein allows for the systematic characterization of new cationic materials with different physicochemical properties for applications ranging from drug and gene delivery to antimicrobial coatings and tissue scaffolds.

Physico-chemical compositions, nutraceutical properties, and starch-related techno-functional, thermal, and morphological characteristics of underutilized yam flour (Dioscorea spp.) from Odisha

High-yielding wild species of yam (Dioscorea spp.) play a vital role in the diet, nutritional, and economic stability of the tribal community. Lack of in-depth research provides scant information on the nutritional value and quality characteristics of tubers. In the present study, physicochemical, nutraceutical, antinutrients, structural, morphological, and thermal properties of lesser-known yam species: Dioscorea pentaphylla (five-leaf yam), Dioscorea bulbifera (bitter yam), Dioscorea hispida (intoxicating yam), and Dioscorea tomentosa (locally called ‘targai kanda’) were investigated. Total protein, fat, fiber, ash, carbohydrate, and metabolic energy of the investigated species are 5.05–8.79%, 0.33–1.01%, 3.53–14.15%, 3.30–5.31%, 62.60–78.26%, and 1241–149 kJ/100 g, respectively. Significant variations (P ≤ 0.05) were observed among the species for antioxidant, bioactive compounds, and physicochemical attributes, where Dioscorea tomentosa exhibited the highest antioxidant capacity. The starch and amylose content varied between 24.7–57.8% and 12.7–29%. X-ray diffractograms of D. pentaphylla and D. bulbifera displayed a B-type pattern, A-type starches in Dioscorea hispida, and CB–type starch for D. tomentosa. The FT-IR spectra confirmed the polysaccharide nature of the yam flours. The particle size ranged between 9.6 and 72.4 μm. The TG/DTG curves revealed that the yam flour could be subjected to cooking up to 180 °C without carbonization. The reported wild yam flours may have tremendous potential for industrial application. However, the study revealed that the presence of antinutrients might affect the mineral bioavailability, cause toxicity, and health hazards. Thus, this could be overcome by processing before safe consumption. The current study also recommended that these wild yam species are safe and can meet potential nutrition and food security through mainstream cultivation.

The acute vapour inhalation toxicity of 2-butoxyethanol. Points considered when designing and conducting a study in Guinea pigs and evaluating existing inhalation toxicity data on low volatility solvents

This publication reports the outcome of an acute inhalation toxicity study with guinea pigs by nose-only exposure to the substance 2-butoxyethanol at exposures close to the maximum attainable saturation vapour concentration. We describe the methods used to ensure exposure only to saturation vapour at a level as high as could be practically achieved whilst avoiding aerosol formation. We consider the practical difficulties and implications of testing substances at or close to their saturation vapour concentration and the criteria that should be used to critically assess such studies, especially with reference to the GHS (Globally Harmonised System) for classification and labelling, where a clear differentiation between gases, vapours and dust and mists applies. Guinea pigs showed no adverse effects when exposed for 4 h to the maximum attainable concentration of pure 2-butoxyethanol vapour. If guinea pigs are regarded as the most appropriate species to assess short term toxicity to humans from exposure to 2-butoxyethanol, because they are like humans not sensitive to haemolysis of red blood cells caused by exposure to the substance, then the data from this study shows that 2-butoxyethanol presents a low acute inhalation toxicity hazard.

Analysis of ortho-phthalates and other plasticizers in select organic and conventional foods in the United States.

ortho-phthalates and other plasticizers impart flexibility to plastics in food production, processing, and packaging; food consumption is a dominant plasticizer exposure pathway. Lower molecular weight ortho-phthalates are being replaced in plastic products due to toxicity concerns, but toxic hazards of and exposures to replacementortho-phthalates and other plasticizers are poorly understood. We measured 12 ortho-phthalates and 9 other plasticizers in conventional and organic U.S. food products to assess magnitude and profiles of contamination. We measured plasticizers in 34 vegetable oils, 10 milks, 18 infant formulas, and 9 cheese powders from macaroni kits using gas chromatography coupled with mass spectrometry (GC-MS). We analyzed plastic packaging composition using FTIR spectroscopy. We detected eight ortho-phthalates and three alternatives ((1,2-cyclohexane dicarboxylic acid diisononyl ester (DINCH), diethylhexyl terephthalate (DEHT), and diisobutyl adipate (DIBA). Diethylhexyl phthalate (DEHP) was measured in all 71 products. DEHT had the highest concentration of any plasticizer (>10,000 ng/g in three oils). Oils had the highest total plasticizer (median = 770 ng/g, max = 14,900 ng/g) and milk the lowest (median = 88 ng/g, max = 120 ng/g). Organic milk and refined oils had higher median plasticizer levels than conventional. Refined oils had significantly lower concentrations than unrefined oils. Maximum contributors for every category were non-ortho-phthalates: DEHT (powdered infant formula and oils) and DIBA (cheese powder, milk and liquid formula). Plasticizers were not detected in packaging except epoxidized soybean oil in liquid formula lids. Human exposure to plasticizers is a significant public health concern. Nevertheless, sources of such exposures are poorly characterized. This study adds valuable information for estimating legacy and alternative plasticizer exposures from foods. The method developed for measuring DINCH, DINP and DIDP broadens the range of plasticizers other researchers may analyze in future work. The profiles of plasticizer contamination varied depending on the food type. We also document that food processing may be a source of plasticizer contamination in foods.

Transformation of Zn and Cr during co-combustion of sewage sludge and coals: influence of coal and steam.

Combustion experiments of sewage sludge (SS) blended with low-rank coal were conducted through a drop tube furnace (DTF) to explore the effects of low-rank coal type, blending ratio, and steam on the transformation of Zn and Cr. The results showed that the retention rates of Zn and Cr in ash increased from 24.35% and 71.49% for sludge combustion alone to 53.77% and 117.49%, respectively, for coal blended to SS with a mass ratio of 7:3. The greater the proportion of low-rank coal in the fuel, the greater the residual rate of heavy metals in the ash. Meanwhile, rapid diffusion of vapor occupied adsorption sites on metal mineral surfaces, reducing the retention of Zn and Cr in the co-combustion ash. The leaching toxicity analysis of ash showed that the co-combustion ash of SS with coal was free from leaching toxicity hazards in simulated scenarios. The extraction rate of Zn in co-combustion ash increased from 90.72% with hydrothermal acid leaching to 95.46% with microwave-assisted in 2mol/L H2SO4 extract. The extraction rate of Cr in hydrothermal acid leaching was 62.80%, which was much higher than that in microwave-assisted extraction (31.76%).

Research Progress in Thermal Runaway Vent Gas Characteristics of Li-Ion Battery

The wide application of lithium-ion batteries (LIBs) brings along with it various safety problems, such as fire and explosion accidents. Aiming at the thermal runaway (TR) and fire problems of LIBs, we reviewed the evolution of TR within LIB and the release of TR gases and their hazards, as well as the research progress in recent years in the area of fire separation of LIBs. To begin with, physical, electrical, and thermal abuse are the three main factors leading to TR and the thermal stability of aging batteries significantly deteriorates. Furthermore, the decomposition of the electrolyte and the reaction between the active materials generates CO, CO2, H2, HF, and a variety of hydrocarbons. These TR gases have serious toxic and explosive hazards. In addition, fire separation can effectively delay the occurrence and propagation of TR within LIB modules. As a good heat-absorbing material, phase-change materials are widely used in the thermal management system and have a great prospect of wide applications in the fire separation of LIBs. Finally, the research on the TR gases’ hazards of aging LIB and safer and more effective fire separation are prospected.

Incorporating patient-reported outcomes in dose-finding clinical trials with continuous patient enrollment

ABSTRACT Dose-finding clinical trials in oncology estimate the maximum tolerated dose (MTD), based on toxicity obtained from the clinician’s perspective. While the collection of patient-reported outcomes (PROs) has been advocated to better inform treatment tolerability, there is a lack of guidance and methods on how to use PROs for dose assignments and recommendations. The PRO continual reassessment method (PRO-CRM) has been proposed to formally incorporate PROs into dose-finding trials. In this paper, we propose two extensions of the PRO-CRM, which allow continuous enrollment of patients and longer toxicity observation windows to capture late-onset or cumulative toxicities by using a weighted likelihood to include the partial toxicity follow-up information. The TITE-PRO-CRM uses both the PRO and the clinician’s information during the trial for dose assignment decisions and at the end of the trial to estimate the MTD. The TITE-CRM + PRO uses clinician’s information solely to inform dose assignments during the trial and incorporates PRO at the end of the trial for the estimation of the MTD. Simulation studies show that the TITE-PRO-CRM performs similarly to the PRO-CRM in terms of dose recommendation and assignments during the trial while almost halving trial duration in case of an accrual of two patients per observation window. The TITE-CRM + PRO slightly underperforms compared to the TITE-PRO-CRM, but similar performance can be attained by requiring larger sample sizes. We also show that the performance of the proposed methods is robust to higher accrual rates, different toxicity hazards, and correlated time-to-clinician toxicity and time-to-patient toxicity data.

Risk assessment of microplastics in fish assemblage based on ecological preferences in an interconnected and polluted river system

Risk assessment of microplastics (MPs) contamination in the assemblage of 15 important fish species with different feeding habits and microhabitats was studied in the River Ravi, Pakistan. Fishes with different feeding habits (omnivore, herbivore, and carnivore) and microhabitat preferences (surface, column, and bottom dweller) were sampled at Balloki and Sidhnai barrages during the post-monsoon seasons of 2019–2020. The gastrointestinal tract (GIT) of fish samples were found to be contaminated with MPs, with an average of 28.1 ± 20.7 MPs/individual and 26.8 ± 15.9 MPs/individual at Balloki and Sidhnai barrages, respectively. The surface dweller fish exhibited the highest MPs abundance, followed by the bottom dweller and column dweller. In addition, the highest MPs recovered from the omnivore generalist feeding group as compared to herbivores and carnivores. The fibers were the most abundant shape and generally made up of polyethylene terephthalate (PET) and polyethylene (PE). These PET and PE (low-density MPs) exhibit low hazard level, whereas high-density MPs with high hazard level and rarely present in GIT of sampled fishes. Based on MP polymer toxicity assessment, nine fish species were categorized in minor risk, two species in medium risk, and four species in highrisk group. Bottom dwelling fishes were at the highest plastic polymer risk level III due to the presence of a high density of MPs with high toxicity hazards. The high-risk prone fishes are under direct threat from MPs pollution, which may disrupt the ecological integrity of the river ecosystem and human health. The findings of the current study highlight the urgent need to address plastic pollution issues in River Ravi, and will be helpful for managers, researchers, and fisheries experts to mitigate this emerging challenge.speciesspecies

New Prospects of Waste Involvement in Marine Fuel Oil: Evolution of Composition and Requirements for Fuel with Sulfur Content up to 0.5%

Research was carried out on the possibility of involving oil refining wastes and petrochemical by-products in marine fuel oil. It was shown that the properties of the studied products (VAT distillation residue of butyl alcohols, heavy pyrolysis tar, desalted phenol production tar, waste motor oil mixture) mainly differ from primary and secondary oil refining products used in this fuel with increased toxicity (hazard classes 2 and 3). A clear disadvantage of waste motor oils is an increased content of metals, particularly zinc, calcium and phosphorus, which leads to high ash content. Recommended concentrations for introducing components into marine fuels are given. The influences of the composition and sulfur content on operational properties and quality indexes of VLSFO were also studied. It is shown that the use of products of deep hydrotreatment of vacuum-distillate fractions of oil processing can worsen its protective (anticorrosive) properties and colloidal stability; therefore, a reduction of sulfur content below 0.1% in this fuel is inexpedient without the use of additives. The requirements for VLSFO quality indicators have been developed. Application of VLSFO corresponding to the developed requirements will provide an increase in performance of ship power plants and the stability of VLSFO quality, which will contribute to cost reduction of ship owners when using it.

A laboratory-scale process for producing dilithium beryllium tetrafluoride (FLiBe) with dissolved uranium tetrafluoride

Flibe Energy, Incorporated (FEI)'s conceptual Lithium Fluoride Thorium Reactor (LFTR) incorporates a chemical processing facility aimed at recovering uranium and other valuable volatile radionuclides while managing harmful radionuclides from the used fuel. The fuel utilized in this reactor is a combination of dilithium beryllium tetrafluoride (Li2BeF4 or FLiBe) and uranium tetrafluoride (UF4), (FLiBe/U). FEI's plan involves extracting the uranium and other valuable volatile fluoride-forming radionuclides using nitrogen trifluoride (NF3). To facilitate laboratory-scale testing of uranium extraction using NF3 and address the toxicity and physical hazards associated with beryllium and beryllium fluoride (BeF2), we used a two-step process to prepare the simulated fuel salt. The first step entailed thermally decomposing ammonium beryllium tetrafluoride [(NH4)2BeF4] (ABeF) through a nominal 3-step process, combined with appropriate amounts of lithium fluoride (LiF) and UF4, resulting in the formation of beryllium fluoride (BeF2). In the second step, the mixture was repeatedly melted and frozen at the melting point of FLiBe to prepare the eutectic FLiBe with dissolved UF4. Although the concept appears straightforward, the production of FLiBe/U involved various challenges. These challenges included transporting the gaseous decomposition products of ABeF, hydrogen fluoride (HF) and ammonia (NH3), while preventing the formation of ammonium fluoride (NH4F). Additionally, it was necessary to control the reaction between the higher-than-anticipated water content in the commercial ABeF with NH3, HF, and the condensed NH4F, protect UF4 from forming an unknown black compound, select suitable structural materials to mitigate fluoride corrosion, address the risks associated with beryllium toxicity through equipment design and operational protocols, and monitor process conditions. This article provides an account of the thermal decomposition chemistry observed in the commercial ABeF, describes the FLiBe/U production apparatus, describes the experiences and process refinements developed to prepare FLiBe/U, and presents our characterizations of prepared FLiBe/U.

Critical attributes and considerations for selecting irrigation systems for wastewater

With increasing global population, the gap between the supply and demand for water is widening and poses a threat to human existence. In the face of water scarcity, urban wastewater is increasing in its attention as an alternate water source for crop production. However, several challenges such as toxicity hazards, salinity build-up and health concerns have been identified with the use of wastewater in agriculture. There are several technological solutions that can help ameliorate or lower the level of contamination associated with using wastewater for irrigation. This paper explores the use of some irrigation technologies to abate the toxicity and health concerns associated with wastewater irrigation. The paper identifies some decision parameters for the selection of identified irrigation technologies and subjects them to multi-criteria decision analysis (MCDA) to rank them based on the level of exposure of the crop and irrigator/field worker to contamination among other relevant criteria. This paper validates that limiting the contact of the wastewater with the edible parts of the crop, especially for leafy vegetables, can minimize contamination to the crop and field workers. Though not totally without constraints, the identified irrigation methods present prospects for a cleaner and more sustainable production with regard to wastewater usage in agriculture. Sub-surface drip irrigation systems were identified as the best irrigation system for filtered and treated wastewater followed by surface drip and pitcher irrigation. Irrigators can fall back on some of these identified methods for wastewater application for sustainable crop production and maximized food safety.