Toxic Components Research Articles

The genus Oxytropis DC: application, phytochemistry, pharmacology, and toxicity.

Oxytropis DC is a perennial plant of Fabaceae family, which is widely distributed in the northern temperate zone. It is known as "locoweed" because of its toxic component swainsonine. However, it is widely used in Tibetan medicine and Mongolian medicine, mainly for the treatment of heat-clearing and detoxifying, pain-relieving, anti-inflammatory, hemostasis, and other diseases. To provide a basis for the further development and utilization of Oxytropis DC, the pieces of literature about the application, phytochemistry, pharmacological action, and toxicity of Oxytropis DC were reviewed and analyzed. A total of 373 chemical constituents were found from Oxytropis DC, including flavonoids, alkaloids, steroids, terpenoids, and others. Pharmacological actions mainly include antitumor, antioxidation, anti-inflammatory, analgesic, antibacterial, antifibrosis, and other pharmacological actions, among them, the antitumor effect is particularly prominent. At present, studies on its pharmacological effects are mainly concentrated on the extracts, some flavonoids, and alkaloids. In the follow-up studies, research on the pharmacological activities of the other chemical constituents in Oxytropis should be strengthened. It has the potential to pave the way for research and development of novel Oxytropis medicines.

Combination of Chemical and Physical Cancer Therapeutics Developed with Microcapsules Made of κ-Casein and Gold Nanoparticles in the Presence of Drug-Loaded Phase Change Materials.

Tumor heterogeneity requires development of an anticancer system equipped with both chemical and physical therapeutics to eradicate cancer exhibiting drug resistance and clonal evolution into diverse tumor cells. Assortment of various toxic components into one platform without compromising their individual toxic activity remains a formidable task. Herein, a novel drug delivery system (DDS) exerting potent cytotoxicity toward cancer cells was fabricated with gold nanoparticles (AuNPs) coated with an innocuous self-assembly protein of κ-casein (κC). Pickering emulsions of the κC-AuNP conjugates in the presence of chloroform inside led to the κC-AuNP microcapsules being stabilized via robust β-sheet formation between κC molecules located on the single-layered shell made of κC-AuNPs. Phase change material (PCM) comprising a eutectic mixture of lauric acid and myristic acid with the melting point of 43 °C was encapsulated in the presence of a hydrophilic anticancer drug of doxorubicin (Dox), in which the PCM has played multiple functions such as drug-holding matrix and thermoresponsive gating material for drug release. Once liberated with the heat generated by the AuNPs upon a near-infrared (NIR) irradiation at 808 nm, the PCM by itself exhibited not only chemical cytotoxicity but also physical toxic effects such as membrane destabilization of the cells and a possible cellular fixative effect toward cancer cells by the solidified PCM at body temperature. Moreover, the PCM was shown to facilitate the intranuclear localization of Dox. As a result, the DDS comprising κC-AuNP microcapsules containing Dox-loaded PCM was demonstrated to show a powerful anticancer effect upon the NIR irradiation, which unleashed several toxic agents such as Dox, PCM, heat-generating AuNPs, and tissue-immobilizing solidified PCM. Therefore, the κC-AuNP microcapsules would serve as an anticancer system into which diverse chemical and physical therapeutic agents could be combined to effectively remove the heterogeneous and drug resistant cancer cells.

Precise subcellular organelle-targeted analyses of the hepatotoxicity of rhubarb

Objective: Drug-induced liver injury (DILI) is the leading cause of acute liver failure and poses a significant challenge to human health. Rhubarb (Rheum officinale Baill.) DaHuang) has been clinically used for its heat-clearing and diuresis-promoting effects. However, its toxic effects on different organelles in the liver require further validation. Methods: We analyzed the potential targets affecting hepatotoxicity in rhubarb and the potential damage relationship with five major organelles, including microsomes, mitochondria, endoplasmic reticulum (ER), Golgi apparatus (GA), and lysosomes through ITCM/HERB databases and network pharmacology. We isolated and purified different organelles, incubated them with different fractions and monomers of rhubarb in an ATP culture system and examined the structural and functional changes in the organelles using particle size analysis and molecular biological experiments to investigate whether rhubarb affects the damage and rupture of major organelles in the liver. Results: By combining virtual predictions and experimental verification, our research confirmed that emodin isolated from the anthraquinone of rhubarb, catechin in the tannins of rhubarb, and palmitic acid in the organic acids of rhubarb caused the most significant functional and structural damage to the representative organelles. Among all the monomeric compounds, emodin caused the most damage to the microsome, mitochondria, ER, and lysosome; catechin induced microsome and GA damage; and palmitic acid caused the most damage to microsomes and GA in the liver, suggesting that rhubarb components may exert hepatotoxicity through multi-organelle injury. Conclusions: Our findings revealed that rhubarb has varying degrees of damaging effects on different organelles, which in turn affects cellular life activities by impairing organelle morphology and function. This study provides a theoretical basis and technical support for a refined analysis of the toxic components and targets of rhubarb.

Qualitative and quantitative studies on the chemical changes during Ayurvedic detoxification process of Acorus calamus Linn. (Indian Vacha)

BackgroundAcorus calamus, commonly known as Vacha holds a significant place in Ayurvedic medicine, addressing memory issues and acting as an anthelminthic. A. calamus rhizomes are known to be toxic due to presence of β-asarone and are used in Ayurvedic medicines only after elaborate processing known as Sodhana (detoxification or purification). As mentioned in Ayurvedic texts like Rasatrangini and Bhaisajya Ratnavali, Sodhana entails the transformation of potentially poisonous plants/substances into non-toxic forms. This study aims to uncover the chemical basis of this ancient detoxification process. Study designThe plant material was detoxified following the methods mentioned in the Ayurvedic Formulary of India. The plant material was boiled in gomutra (cow urine) and decanted. Subsequently, it was boiled with Spaeranthus indicus (Alambusa kwath) and then with Panchpallav kwath (a decoction of leaves from five different plants). The plant material so obtained was dried and subjected to swedana (steam distillation), dried again and extracted to obtain processed (detoxified) extract. Both the unprocessed and processed extracts were analyzed for secondary metabolites using HPLC, LCMS, and 1H NMR. ResultsThis study demonstrated that detoxification process resulted in morphological changes in rhizome, almost ten-fold reduction in extractive yield, reduced amount of major toxic component β-asarone and other toxic metabolites like asaronaldehyde, acorone, calamusin, acoraminol, acoramone, 1,2-dihydroxyasarone, asarotonide, propioveratrone, azulene and calamol in the extract, and isomerisation of β-asarone to α-asarone. Further the toxic metabolites were screened for genotoxicity by molecular docking. ConclusionOur findings have identified the chemical basis of Ayurvedic detoxification process.

Inhaled pollutants of the Gero-Exposome and later life health.

Inhaled air pollutants (AirP) comprise extraordinarily diverse particles, volatiles, and gases from traffic, wildfire, cigarette smoke, dust, and various other sources. These pollutants contain numerous toxic components which collectively differ in relative levels of components, but broadly share chemical classes. Exposure and health outcomes from AirP are complex, depending on pollutant source, duration of exposure, and socioeconomic status. We discuss examples in the current literature on organ responses to AirP, with a focus on lung, arteries, and brain. Some transcriptional responses are shared. It is well accepted that AirP contributes to Alzheimer's disease and other neurodegenerative conditions in the Gero-Exposome. However, we do not know which chemical compounds initiate these changes and how activation of these transcriptional pathways is further modified by genetics and prenatal development.

Pseudomonas mosselii: a potential alternative for managing pyrethroid-resistant Aedes aegypti.

Aedes aegypti is a widespread mosquito in tropical and subtropical regions that causes significant mortality and morbidity in humans by transmitting diseases, such as dengue fever and Zika virus disease. Synthetic insecticides, such as pyrethroids, have been used to control Ae. aegypti, but these insecticides can also affect nontarget organisms and contaminate soil and water. This study aimed to investigate the mosquitocidal activity of Pseudomonas mosselii isolated from pond sludge against larvae of Ae. aegypti. Based on the initial results, similar time-course profiles were obtained for the mosquitocidal activity of the bacterial culture and its supernatant, and the pellet resuspended in Luria-Bertani (LB) medium also showed delayed toxicity. These results imply that the toxic component can be released into the medium from live bacteria. Further research indicated that the toxic component appeared in the supernatant approximately 4 h after a 3-mL stock was cultured in 200 mL of LB medium. The stabilities of the P. mosselii culture and supernatant stored at different temperatures were also evaluated, and the best culture stability was obtained at 28 °C and supernatant stability at 4 °C. The bacterial culture and supernatant were toxic to larvae and pupae of not only susceptible Ae. aegypti but also pyrethroid-resistant strains. This study highlights the value of the mosquitocidal activity of P. mosselii, which has potential as an alternative insecticide to control pyrethroid-resistant Ae. aegypti in the field. © 2024 Society of Chemical Industry.

Toxic and Environmental Effects of Neonicotinoid Based Insecticides

The insecticide known as neonicotinoid has negative impacts on the ecosystem, human health, and the environment; specifically, its effects on the relationship between crop yields and the death rate of natural pollinators, such as bees, affect food security. The active ingredients in neonicotinoids include imidacloprid, clothianidin, thiamethoxam, acetamiprid, sulfoxaflor, and thiacloprid, which are sold under various trade names. For many of the components of these toxic insecticides, patents have been expired; however, farmers and consumers who continue to use these chemicals are unaware of the products’ toxicity and the environmental effects they have. Thus, agricultural industries are required to consider diverse methods to minimize neonicotinoid use in farming operations and move away from the current prevailing methods. In this short review, the negative effects of neonicotinoid use; the toxic components, health effects, and environmental regulations of neonicotinoids; and sustainable methods to minimize their use are examined.

Integration of sequential electrocoagulation and adsorption for effective removal of colour and total organic carbon in textile effluents and its utilization for seed germination and irrigation.

Textile effluent discharge can negatively impact the environment and living organisms due to its potential toxicity, higher percentages of total organic carbon (TOC) contents, and so on. The study investigates the extraordinary performance of the electrocoagulation process (ECP) combined with powdered activated carbon (PAC) as a highly effective and environmental friendly method of treating textile effluents. This scientific work mainly includes the focus on removing toxic components in textile effluents, such as high concentrations of colour and TOC using synthesized PAC derived from coconut shells coupled with the ECP (ECP-PAC). Initially, PAC was characterized by using XRD, Raman, BET, FTIR, and TGA studies. Subsequently, the pilot-scale ECP-PAC batch reactor was constructed with iron (Fe) as an anode and copper (Cu) as a cathode. The pilot-scale ECP-PAC batch reactor has achieved higher treatment efficiency in a shorter reaction time with low energy consumption compared to a stand-alone ECP. Further, the optimum conditions for effective ECP-PAC have been optimized, such as pH 7.5, applied current density (0-50mA/cm2), reaction time (0-30min), electrode combinations (Fe-Cu) with electrode distances of 5cm apart, and an optimum dose of 5g/L of PAC. Specifically, 98% of the colour and 96% of the TOC contents present in the industrial textile effluent were treated in 15 and 30min, respectively. In quantitative perspectives, the developed batch reactor has sharply decreased TOC (324.1mg/L), IC (1410mg/L) and TC (1019mg/L) to 13.55mg/L (96%), 31.49mg/L (97%), and 48.05mg/L (95%), respectively, in 30min demonstrating its sensitivity and selectivity with the utmost care. Moreover, the physicochemical properties of the treated water were convincingly assessed. That is, it remains suitable for the seed germination of mung bean and chlorophyll content study. Thus, the developed methodology could effectively reduce freshwater consumption in the agricultural sector, increase freshwater availability in water-scarce regions, and facilitate the increase of the recharging capacity of groundwater tables.

Phytochemicals derived from Nicotiana tabacum L. plant contribute to pharmaceutical development.

The Nicotiana tabacum L. plant, a medicinal resource, holds significant potential for benefiting human health, as evidenced by its use in Native American and ancient Chinese cultures. Modern medical and pharmaceutical studies have investigated that the abundant and distinctive function metabolites in tobacco including nicotine, solanesol, cembranoid diterpenes, essential oil, seed oil and other tobacco extracts, avoiding the toxic components of smoke, mainly have the anti-oxidation, anti-lipid production, pro-lipid oxidation, pro-insulin sensitivity, anti-inflammation, anti-apoptosis and antimicrobial activities. They showed potential pharmaceutical value mainly as supplements or substitutes for treating neurodegenerative diseases including Alzheimer's and Parkinson's disease, inflammatory diseases including colitis, arthritis, sepsis, multiple sclerosis, and myocarditis, and metabolic syndrome including Obesity and fatty liver. This review comprehensively presents the research status and the molecular mechanisms of tobacco and its metabolites basing on almost all the English and Chinese literature in recent 20 years in the field of medicine and pharmacology. This review serves as a foundation for future research on the medicinal potential of tobacco plants.

Probiotic Pediococcus pentosaceus restored gossypol-induced intestinal barrier injury by increasing propionate content in Nile tilapia

BackgroundIntestinal barrier is a dynamic interface between the body and the ingested food components, however, dietary components or xenobiotics could compromise intestinal integrity, causing health risks to the host. Gossypol, a toxic component in cottonseed meal (CSM), caused intestinal injury in fish or other monogastric animals. It has been demonstrated that probiotics administration benefits the intestinal barrier integrity, but the efficacy of probiotics in maintaining intestinal health when the host is exposed to gossypol remains unclear. Here, a strain (YC) affiliated to Pediococcus pentosaceus was isolated from the gut of Nile tilapia (Oreochromis niloticus) and its potential to repair gossypol-induced intestinal damage was evaluated.ResultsA total of 270 Nile tilapia (2.20 ± 0.02 g) were allotted in 3 groups with 3 tanks each and fed with 3 diets including CON (control diet), GOS (control diet containing 300 mg/kg gossypol) and GP (control diet containing 300 mg/kg gossypol and 108 colony-forming unit (CFU)/g P. pentosaceus YC), respectively. After 10 weeks, addition of P. pentosaceus YC restored growth retardation and intestinal injury induced by gossypol in Nile tilapia. Transcriptome analysis and siRNA interference experiments demonstrated that NOD-like receptors (NLR) family caspase recruitment domain (CARD) domain containing 3 (Nlrc3) inhibition might promote intestinal stem cell (ISC) proliferation, as well as maintaining gut barrier integrity. 16S rRNA sequencing and gas chromatography-mass spectrometry (GC-MS) revealed that addition of P. pentosaceus YC altered the composition of gut microbiota and increased the content of propionate in fish gut. In vitro studies on propionate’s function demonstrated that it suppressed nlrc3 expression and promoted wound healing in Caco-2 cell model.ConclusionsThe present study reveals that P. pentosaceus YC has the capacity to ameliorate intestinal barrier injury by modulating gut microbiota composition and elevating propionate level. This finding offers a promising strategy for the feed industry to incorporate cottonseed meal into fish feed formulations.Graphical

The association between PM2.5 components and blood pressure changes in late pregnancy: A combined analysis of traditional and machine learning models

BackgroundPM2.5 is a harmful mixture of various chemical components that pose a challenge in determining their individual and combined health effects due to multicollinearity issues with traditional linear regression models. This study aimed to develop an analytical methodology combining traditional and novel machine learning models to evaluate PM2.5's combined effects on blood pressure (BP) and identify the most toxic components. MethodsWe measured late-pregnancy BP of 1138 women from the Heshan cohort while simultaneously analyzing 31 p.m.2.5 components. We utilized multiple linear regression modeling to establish the relationship between PM2.5 components and late-pregnancy BP and applied Random Forest (RF) and generalized Weighted Quantile Sum (gWQS) regression to identify the most toxic components contributing to elevated BP and to quantitatively evaluate the total effect of the PM2.5 component mixtures. ResultsThe results revealed that 16 p.m.2.5 components, such as EC, OC, Ti, Fe, Mn, Cu, Cd, Mg, K, Pb, Se, Na+, K+, Cl−, NO3−, and F−, contributed to elevated systolic blood pressure (SBP), while 26 components, including two carbon components (EC, OC), fifteen metallics (Ti, Fe, Mn, Cr, Mo, Co, Cu, Zn, Cd, Na, Mg, Al, K, Pb), one metalloid (Se), and nine water-soluble ions (Na+, K+, Mg2+, Ca2+, NH4+, Cl−, NO3−, SO42−, F−), contributed to elevated diastolic blood pressure (DBP). Mn and Cr were the most toxic components for elevated SBP and DBP, respectively, as analyzed by RF and gWQS models and verified against each other. Exposure to PM2.5 component mixtures increased SBP by 1.04 mmHg (95% CI: 0.33–1.76) and DBP by 1.13 mmHg (95% CI: 0.47–1.78). ConclusionsOur study highlights the effectiveness of combining traditional and novel models as an analytical strategy to quantify the health effects of PM2.5 constituent mixtures.

Autophagic-lysosomal damage induced by swainsonine is protected by trehalose through activation of TFEB-regulated pathway in renal tubular epithelial cells

Swainsonine (SW) is the main toxic component of locoweed. Previous studies have shown that kidney damage is an early pathologic change in locoweed poisoning in animals. Trehalose induces autophagy and alleviates lysosomal damage, while its protective effect and mechanism against the toxic injury induced by SW is not clear. Based on the published literature, we hypothesize that transcription factor EB(TFEB) -regulated is targeted by SW and activating TFEB by trehalose would reverse the toxic effects. In this study, we investigate the mechanism of protective effects of trehalose using renal tubular epithelial cells. The results showed that SW induced an increase in the expression level of microtubule-associated protein light chain 3-II and p62 proteins and a decrease in the expression level of ATPase H+ transporting V1 Subunit A, Cathepsin B, Cathepsin D, lysosome-associated membrane protein 2 and TFEB proteins in renal tubular epithelial cells in a time and dose-dependent manner suggesting TFEB-regulated lysosomal pathway is adversely affected by SW. Conversely, treatment with trehalose, a known activator of TFEB promote TFEB nuclear translocation suggesting that TFEB plays an important role in protection against SW toxicity. We demonstrated in lysosome staining that SW reduced the number of lysosomes and increased the luminal pH, while trehalose could counteract these SW-induced effects. In summary, our results demonstrated for the first time that trehalose could alleviate the autophagy degradation disorder and lysosomal damage induced by SW. Our results provide an interesting method for reversion of SW-induced toxicity in farm animals and furthermore, activation of TFEB by trehalose suggesting novel mechanism of treating lysosomal storage diseases.

Blocking the dimerization of polyglutamine-expanded androgen receptor protects cells from DHT-induced toxicity by increasing AR turnover

Spinal and bulbar muscular atrophy (SBMA) is a neuromuscular degenerative disease caused by a polyglutamine expansion in the androgen receptor (AR). This mutation causes AR to misfold and aggregate, contributing to toxicity in and degeneration of motor neurons and skeletal muscle. There is currently no effective treatment or cure for this disease. The role of an interdomain interaction between the amino- and carboxyl-termini of AR, termed the N/C interaction, has been previously identified as a component of androgen receptor-induced toxicity in cell and mouse models of SBMA. However, the mechanism by which this interaction contributes to disease pathology is unclear. This work seeks to investigate this mechanism by interrogating the role of AR homodimerization- a unique form of the N/C-interaction- in SBMA. We show that, although the AR N/C-interaction is reduced by polyglutamine-expansion, homodimers of 5α-dihydrotestosterone (DHT)-bound AR are increased. Additionally, blocking homodimerization results in decreased AR aggregation and toxicity in cell models. Blocking homodimerization results in the increased degradation of AR, which likely plays a role in the protective effects of this mutation. Overall, this work identifies a novel mechanism in SBMA pathology that may represent a novel target for the development of therapeutics for this disease.

Internally cooled tools as an innovative solution for sustainable machining: Temperature investigation using Inconel 718 superalloy

Machining is a process that involves intense heat generation at localized points within the tool-chip interface. This leads to elevated temperatures, which can be detrimental to cutting tools. This issue becomes even more crucial when dealing with superalloys like Inconel 718, as they exhibit high shear strength and good creep resistance. Consequently, a significant amount of energy is expended, increasing the cutting temperature. Until now, the primary technique employed to address this issue has been using Cutting Fluids (CFs). In machining, a portion of costs is attributed to fluid handling. It also contains harmful elements that can pose health risks, potentially leading to conditions such as cancer. Moreover, the toxic components can contribute to environmental degradation when improperly disposed of. Therefore, this study proposes an innovative cooling technique called Internally Cooled Tools (ICTs). The ICTs employ an internally circulating coolant fluid through closed cooling channels within the cutting tools, eliminating fluid dispersion into the atmosphere. The main objective was to compare the performance of ICTs in controlling the tool-chip interface temperature during Inconel 718 turning using hard metal tools. For this purpose, a complete factorial experimental design (25) was utilized, with the response variable being the temperature measured by the tool-work thermocouples technique. Beyond that, a sustainable assessment was performed using the Pugh Matrix method. Many key sustainable factors were evaluated related to three atmospheres, cutting fluids in abundance – CFA, dry machining, and ICT. The data base used was a depth literature investigation together with results found in this work. The main findings of this entire work demonstrated that an increase in cutting parameters corresponded to an increase in temperature, as anticipated. TiNAl coating reduced the temperature by up to 10% compared to uncoated tools. Similarly, applying ICTs led to temperature reductions of up to 17% compared to dry machining conditions. The Pugh Matrix made considering 12 factors showed that ICT (14 points) was the most sustainable lubri-cooling method in comparison to CFA (3) and DM (5). Ultimately, ICTs showed to be a promising eco-friendly method. It outperformed conventional methods, showcasing a remarkable heat dissipation capacity. As a result, further studies are warranted to delve deeper into this promising approach.

Pd-Adsorbed SiN3 Monolayer as a Promising Gas Scavenger for SF6 Partial Discharge Decomposition Components: Insights from the First-Principles Study.

Gas-insulated switchgear (GIS) equipment must be protected by detecting and eliminating the toxic SF6 partial discharge decomposition components. This study employs first-principles calculations to thoroughly investigate the interaction between a Pd-adsorbed SiN3 monolayer (Pd-SiN3) and four typical SF6 decomposition gases (H2S, SO2, SOF2, and SO2F2). The study also investigates the associated geometric, electrical, and optical characteristics along with the sensing sensitivity and desorption efficiency. The ab initio molecular dynamics (AIMD) simulations demonstrated the favorable stability of the Pd-SiN3 monolayer. Furthermore, the Pd-SiN3 monolayer exhibited strong chemisorption behavior toward H2S, SO2, SOF2, and SO2F2 gases because of the higher adsorption energies of -2.717, -2.917, -2.457, and -2.025 eV, respectively. Furthermore, significant changes occur in the electronic and optical characteristics of the Pd-SiN3 monolayer following the adsorption of these gases, resulting in remarkable sensitivity of the Pd-SiN3 monolayer in relation to electrical conductivity and optical absorption. Meanwhile, all of these gas adsorption systems exhibited extremely long recovery times. The aforementioned theoretical findings suggest that the Pd-SiN3 monolayer has the potential to be an effective gas scavenger for the storage or removal of the SF6 decomposition components. Additionally, it might function as a reliable one-time sensor for detecting these gases. The results potentially provide valuable theoretical guidance for maintaining the normal operation of the SF6 insulation devices.

Approaches to Use Anti-nutritional Factors Containing Plant Based Protein-rich Aquafeeds

Replacement of the fish meal as a protein source in the aquafeeds is required these days due to the high cost of fish meal and its uncertain availability. Aquatic animals rely on fish meal for protein source so the protein source used in place of fish meal must not alter the nutritional quality of the feed. Therefore, such alternatives include animal and plant by- products such as meat, bone meal, rapeseed meal, soybean meal, corn gluten meal, a meal of protein- rich leaves, etc. However, the presence of anti-nutritional substances such as phytic acid, tannin, saponin, cyanide, oxalate, phytoestrogens, and gossypol limits the use of plant ingredients because ANFs have various side effects such as poor intestinal inflammation, oxidative stress, and decreased growth rate in many fish. To reduce the harmful effects several techniques such as solvent extraction, dry and wet heating, enzyme treatment, etc are used to reduce or eliminate such toxic components from Aquafeed. Amelioration strategies help in removal of anti-nutritional factors from plant based extract and are helpful in production of nutrient- rich and cost effective feed for fish for better growth and viability.

High spatial-resolved source-specific exposure and risk in the city scale: Influence of spatial interrelationship between PM2.5 sources and population on exposure

Research on High Spatial-Resolved Source-Specific Exposure and Risk (HSRSSER) was conducted based on multiple-year, multiple-site synchronous measurement of PM2.5-bound (particulate matter with aerodynamic diameter<2.5 μm) toxic components in a Chinese megacity. The developed HSRSSER model combined the Positive Matrix Factorization (PMF) and Land Use Regression (LUR) to predict high spatial-resolved source contributions, and estimated the source-specific exposure and risk by personal activity time- and population-weighting. A total of 287 PM2.5 samples were collected at ten sites in 2018–2020, and toxic species including heavy metals (HMs), polycyclic aromatic hydrocarbons (PAHs) and organophosphate esters (OPEs) were analyzed. The percentage non-cancer risk were in the order of traffic emission (48 %) > industrial emission (22 %) > coal combustion (12 %) > waste incineration (11 %) > resuspend dust (7 %) > OPE-related products (0 %) ≈ secondary particles (0 %). Similar orders were observed in cancer risk. For traffic emission, due to its higher source contributions and large population in central area, non-cancer and cancer risk fraction increased from 23 % to 48 % and 20 % to 46 % after exposure estimation; while for industrial emission, higher source contributions but small population in suburb area decreased the percentage non-cancer and cancer risk from 38 % to 22 % and 39 % to 24 %, respectively.

High toxin concentration in pollen may deter collection by bees in butterfly-pollinated Rhododendron molle.

The hypothesis that plants evolve features that protect accessible pollen from consumption by flower visitors remains poorly understood. To explore potential chemical defenses against pollen consumption, we examined the pollinator assemblage, foraging behaviour, visitation frequency and pollen transfer efficiency in Rhododendron molle, a highly toxic shrub containing Rhodojaponin III. Nutrient (protein and lipid) and toxic components in pollen and other tissues were measured. Overall in the five populations, floral visits by butterflies and bumblebees were relatively more frequent than visits by honeybees. All foraged for nectar but not pollen. Butterflies did not differ from bumblebees in the amount of pollen removed per visit, but deposited more pollen per visit. Pollination experiments indicated that R. molle was self-compatible, but both fruit and seed production were pollen limited. Our analysis indicated that the pollen was not protein-poor and had a higher concentration of the toxic compound Rhodojaponin III than petals and leaves, which compound was undetectable in nectar. Pollen toxicity in Rhododendron flowers may discourage pollen robbers (bees) from taking the freely accessible pollen grains, while the toxin-free nectar rewards effective pollinators, promoting pollen transfer. This preliminary study supports the hypothesis that chemical defense in pollen would be likely to evolve in species without physical protection from pollinivores.

Una ingesta explosiva

The ingestion of firecrackers poses a potential risk to the patient's life if they contain the toxic component called yellow phosphorus (YFP). Fortunately, this material is not currently used in our country for the manufacture of pyrotechnic products, but this is not the case in other regions of the world such as Asia or Latin America. The ingestion of FA can cause the death of the patient in up to 20-50% of them by toxic accumulation in the organism, producing mainly hepatic failure and consequently multiorgan failure. Firecrackers in Spain contain non-toxic materials for the organism, so their ingestion may cause nausea and abdominal discomfort, but not a lethal risk for the patient.

Simulation of alternative fuel combustion process in internal combustion engines

BACKGROUND: The tasks of improving fuel efficiency and environmental performance of engines are interrelated with the technical, economic, resource performance and reliability of their operation.&#x0D; AIM: In this regard, the aim is simulation of the alternative fuels combustion process.&#x0D; METHODS: To achieve this aim, the method for preparing a water-fuel emulsion mixed with diesel fuel has been developed and experimental studies have been carried out with the measurement of toxic components of exhaust gases from diesel engines.&#x0D; RESULTS: As a result of the research, the most optimal droplet sizes of water-fuel emulsions were revealed after 4–6 processing cycles with the smokiness reduction by 3 to 5 times, the NOx reduction by 2 to 3 times, the CO reduction by 20–30%, depending on the operating modes.&#x0D; CONCLUSIONS: As a result of the research, it was found that the use of alternative fuels makes it possible to expand the fuel balance and to improve environmental performance.