Optimization of chokeberry extraction, Aronia melanocarpa (Michx.) Elliott, extract microencapsulation by electrostatic extrusion and spray drying methods

Poslednjih godina sve je više aktuelna potreba za primenom i proučavanjem alternativnih prirodnih supstanci, antioksidanasa kojima bi se postiglo ciljano zaštitno dejstvo na organizam. Ispitivanje antioksidanasa, posebno prirodnog porekla danas je u fokusu farmaceutskih istraživanja. Po najvećem antioksidativnom kapacitetu ističe se bobičasto voće tamno plave ili ljubičaste boje, a meñu njima po najvećoj antioksidativnoj aktivnosti odnosno sadržaju polifenola, izdvajaju se plodovi aronije. Interesovanje za bobičasto voće, a posebno aroniju je sve veće proteklih godina, jer visok unos može imati povoljne efekte na smanjenje rizika od nastanka kardiovaskularnih, malignih i različitih degenerativnih bolesti. Aronija (Aronia melanocarpa (Michx.) Elliott) pripada familiji Rosacea i jedan je od najbogatijih izvora polifenolnih jedinjenja, u kojima dominiraju antocijani, proantocijanidini, fenolne kiseline, flavanoli. Na našim prostorima prisutna je više od 50 godina, ali je u široj upotrebi poslednjih nekoliko godina. Aktivni principi aronije predstavljaju jedan od najpotentnijih prirodnih antioksidanasa. Zbog toga su izolacija i identifikacija biološki aktivnih jedinjenja iz ploda aronije, njihova dalja primena u vidu obogaćivanja različitih proizvoda ovim jedinjenjima, primena kao dodatka ishrani, trenutno jedna od najaktuelnijih naučno-istraživačkih tema. Aronija je na tržistu dostupna u vidu svežih i suvih plodova, soka, džemova, ali je nedovoljno zastupljena u vidu različitih fitopreparata, ekstrakata ili dijetetskih suplemenata, pa je interesovanje za dobijanje ovih preparata, a pre svega ekstrakata sve veće. Meñutim, primena ekstrakata bogatih polifenolima ima i niz ograničenja, a pre svega nestabilnost, jer aktivni principi iz ekstrakta su osetljivi na prisustvo kiseonika, svetlosti, vlage i drugih nepovoljnih faktora, a posebno su osetljivi antocijani. Jedna od metoda koja može da se primeni za očuvanje biološki aktivnih jedinjenja iz ekstrakata ploda aronije i smanjenje njihove nestabilnosti je mikroinkapsulacija. Ovom metodom se postiže očuvanje stabilnosti ekstrahovanih aktivnih principa, produženje roka trajanja, zaštita od negativnih uticaja spoljašnje sredine, njihovo kontrolisano oslobañanje, pokrivanje gorkog ukusa polifenola, i sprečavanje negativnog dejstva gastrointestinalnog trakta...Introduction. In recent years, there is a growing interest for application and investigation of alternative natural substances, antioxidants which could achieve protective effects on human health. Examination of antioxidants, especially of natural origin nowdays represents the main focus in pharmaceutical research. Among many plants, berry friuts and especially dark blue or purple ones have the most antioxidant capacity, which include the highest antioxidant activity and polyphenol content, especially in the case of chokeberry. Growing interest in berries, peculiary in chokeberry is in increasing in the recent past years because their high intake may have beneficial effects on reducing the cardiovascular risks, cancer and various degenerative diseases. Chokeberry (Aronia melanocarpa (Michx.) Elliott) belongs to the Rosacea family, and it is one of the richest sources of polyphenol compounds, particular in anthocyanins, proanthocyanidins, phenolic acids, flavanols. In our country chokeberry exists more than 50 years, but is widely used in recent past. The active principles of chokeberry represent one of the most potent natural antioxidants. Therefore, the isolation and identification of chokeberry biologically active compounds, their further application in terms of enrichment the different products with these compounds, the possibility for their use as a dietary supplements are currently one of the most scientific and research topics. Chokeberry is available on the market in the form of fresh and dry fruits, juice, jams, but it is not enough represent in the form of various herbal remedies, extracts or dietary supplements, and there is growing interest in obtaining an extract rich in their active principles. However, the use of extracts rich in polyphenols has a number of limitation, extract instability due to the effects of oxygen, light, moisture and other adverse factors. Anthocyanins are especially sensitive among all polyphenols. One of the methods that can be applied for the preservation of biologically active compounds of chokeberry extract and which can reduce their instability is microencapsulation technology. This method could preserve the stability of the active principles, their shelf life extension, protection from the negative impact of the external environment, controlled release, covering the polyphenols bitter taste and preventing the negative effects of the gastrointestinal tract..

The effect of steroid hormones and their antagonists on galectinsʼ levels in human trophoblast cells in vitro

Galektini su evolutivno očuvana grupa lektina, sa afinitetom prema β-galaktozidnoj strukturi. Zahvaljujući lektinskoj aktivnosti, galektini su uključeni u regulaciju vitalnih ćelijskih procesa kao što su preživljavanje ćelija, apoptoza, regulacija ćelijskog ciklusa, obrada iRNK transkripta, ćelijska adhezija i migracija. Postoje indicije da su galektini uključeni u različite reproduktivne procese, uključujući i proces implantacije embriona i placentacije, kao preduslova za razvoj fetusa. Iako mehanizmi nisu nedovoljno poznati, ekspresija galektina je precizno regulisana i može biti specifična za određeno tkivo ili fazu razvića. Steroidni hormoni imaju važnu ulogu u pripremi, uspostavljanju i održavanju trudnoće. Ćelije ekstravilusnog trofoblalsta (EVT) ne sintetišu steroidne hormone, ali prisustvo odgovarajućih receptora omogućava da steroidni hormoni mogu ispoljiti svoje delovanje na ove ćelije. U ćelijama EVT je pokazano prisustvo galektina-1, -3 i -8. Poznavanje regulacije ekspresije galektina u EVT je veoma oskudno, ali postoje podaci za druga tkiva koji ukazuju na ulogu steroidnih hormona. U promotorskim regionima gena za ova tri galektina prisutne su odgovarajuće hormon-response sekvence, pa postoji mogućnost da steroidni hormoni mogu uticati na ekspresiju galektina-1, -3 i -8. U ovom radu je ispitan uticaj steroidnih hormona progesterona (P4), 17β-estradiola (E2) i testosterona (TE), zatim sintetskog analoga kortizola, deksametazona (DEX), kao i odgovarajućih antagonista steroidnih hormona na nivoe galektina-1, -3 i -8 u EVT ćelijskoj liniji HTR-8/SVneo. Efekat je praćen na nivou genske ekspresije, sadržaja galektina unutar ćelija, kao i mogućim promenama u sekreciji. Dobijeni rezultati su pokazali da su galektini-1, -3 i -8 u EVT ćelijskoj liniji HTR-8/SVneo modulirani steroidnim hormonima, steroid specifično i zavisno od doze. Steroidni hormoni mogu različito delovati na transkripciju gena (iRNK), na nivoe intracelularnih galektina, odnosno na galektine sekretovane van ćelija. Nivo iRNK za LGALS1, kao i nivoi galektina-1 u ćelijama i galektin-1 oslobađen van ćelija su bili povišeni pri koncentraciji od 10 nM E2, dok su pri višoj koncentraciji (1000 nM) bili smanjeni. S druge strane, nivo proteina galektina-3 i njegova sekrecija su stimulisani P4 (10 nM). U prisustvu mifepristona, antagonista glukokoritikoida i progesterona, uočen je efekat na nivoe galektina-1 i -3 suprotan u odnosu na P4, što sugeriše da je ova regulacija posredovana progesteronskim receptorom. Iako su uočene najmanje promene kod galektina-8 pod uticajem steroidnih hormona, njegova sekrecija je povećana nakon tretmana P4, DEX i E2 (10 nM)...Galectins are an evolutionarily conserved lectin family, with affinity for β-galactosides. Galectins are involved in regulation of vital cellular processes such as cell survival and apoptosis, regulation of cell cycle, RNA splicing, cell adhesion and migration. Galectins are assumed to participate in different reproductive processes including embryo implantation and placentation, and fetal development. Despite paucity of data, galectins seem to be precisely regulated, they are expressed in different tissues, or are specific for certain developmental phases. Steroid hormones are well known for their role in priming, establishing and maintenance of pregnancy. Extravillous trophoblast (EVT) cells do not synthesize steroid hormones, but are steroid-responsive, and steroid receptors are expressed in EVT cells. Three members of the galectin family are detected in EVT, galectin-1, -3 and -8. However, not much is known regarding regulation of galectins’ expression in EVT. The presence of corresponding hormone-response sequences in promotors of genes for galectins indicate that steroid hormones could regulate galectins-1, -3 and -8. In this study, the effect of steroid hormones progesterone (P4), 17β-estradiol (E2) and testosterone (TE), synthetic cortisol analog dexamethasone (DEX), as well as relevant steroid hormone antagonists on galectin-1, -3 and -8 levels in EVT cell line HTR-8/SVneo was investigated. The effect was studied at both RNA and galectin protein levels, following intracellular content, and secreted galectins. The results obtained showed that galectins-1, -3 and -8 in EVT cell line HTR-8/SVneo are modulated by steroid hormones, in steroid and dose-specific manner. Steroid hormones had different impact at gene expression (mRNA level), intracellular galectins and secreted galectins. LGALS1 gene expression, total cellular galectin-1 and secretion of this protein were increased with low concentration of E2 (10 nM), while higher concentration (1000 nM) had inhibitory effect on mRNA, total cellular galectin-1 and galectin-1 secretion. On the other hand, intracellular galectin-3, and secretion of galectin-3 were increased with P4 (10 nM). Mifepristone, a synthetic, steroidal antiprogestogen and antiglucocorticoid, had the opposite effect to P4 on galectin-1 and -3 levels, suggesting the progesterone receptor involvement. Galectin-8 was the least sensitive to treatment with steroid hormones. Nevertheless, secretion of galectin-8 was increased with P4, DEX and E2 (10 nM). Estradiol was also found to affect function of EVT in vitro, dose-independently inhibitting cell migration and invasion..

Effect of steroids on transcription and secretion of Gal-1 by the human trophoblast cell line in vitro

Galectin-1 (Gal-1) is a lectin with recently documented pro-invasive function in trophoblasts in vitro, whose regulation is currently insufficiently known. The potential involvement of steroid hormones, synthetic glucocorticoid dexamethasone (DEX), the sex steroid progesterone (PRG) and mifepristone (RU486) in the regulation of Gal-1 in the trophoblast-derived cell line HTR-8/SVneo was investigated. Gal-1 mRNA levels were assessed by real-time PCR. The effect on secretion of Gal-1 into the culture media was followed using the SELDI-TOF protein chip array. We present evidence that DEX and RU486 significantly reduced Gal-1 in the HTR-8/SVneo cell line at the mRNA level. In addition, trophoblast-derived HTR-8/SVneo cells were shown to secrete detectable Gal-1 protein, which was only slightly increased by PRG. The potential clinical relevance of these findings remains to be determined

Effect of steroids on transcription and secretion of Gal-1 by the human trophoblast cell line in vitro

Galectin-1 (Gal-1) is a lectin with recently documented pro-invasive function in trophoblasts in vitro, whose regulation is currently insufficiently known. The potential involvement of steroid hormones, synthetic glucocorticoid dexamethasone (DEX), the sex steroid progesterone (PRG) and mifepristone (RU486) in the regulation of Gal-1 in the trophoblast-derived cell line HTR-8/SVneo was investigated. Gal-1 mRNA levels were assessed by real-time PCR. The effect on secretion of Gal-1 into the culture media was followed using the SELDI-TOF protein chip array. We present evidence that DEX and RU486 significantly reduced Gal-1 in the HTR-8/SVneo cell line at the mRNA level. In addition, trophoblast-derived HTR-8/SVneo cells were shown to secrete detectable Gal-1 protein, which was only slightly increased by PRG. The potential clinical relevance of these findings remains to be determined. [Projekat Ministarstva nauke Republike Srbije, br. 173004

Justification, Optimization and Reference Levels in Existing Exposure Situations

U radu su razmatrani zahtevi za upravljanje situacijama postojećeg izlaganja a naročito primena principa opravdanosti i optimizacije zaštite, odnosno uvođenje referentnih nivoa za uspostavljanje kontrole nad ovim situacijama. Diskutovane su preporuke iz standarda MAAE i regulative Evropske unije, koje su zasnovane na nalazima Međunarodnog komiteta za zaštitu od zračenja, kao i relevantne odredbe propisa Republike Srbije. Istaknut je značaj donošenja dugoročne Strategije upravljanja situacijama postojećeg izlaganja, sa odgovarajućim akcionim planovima za implementaciju.The requirements for managing situations of existing exposure, and especially the implementation of the principles of justification and optimization of protection, and introduction of reference levels for establishing control over these situations have been discussed in the paper. Reccomendations given by the IAEA standards and EU regulations, which are based on the findings of the International Committee on Radiation Protection were considered as well as certain provisions of the regulations of the Republic of Serbia. The need and importance of adopting a long-term strategy for managing existing exposure situations, with appropriate action plans for implementation, was highlighted.XXXII Simpozijum Društva za zaštitu od zračenja Srbije i Crne Gore, 4-6. oktobar 2023; Budva, Crna GoraProceedings: [https://vinar.vin.bg.ac.rs/handle/123456789/11602

Antocijani - hemijska analiza i biološka aktivnost

Anthocyanins are a group of over 500 different compounds that cause red, purple and blue colours of many plants, especially fruits, vegetables and cereals. Anthocyanins structurally belong to flavones. Mainly fruit is considered the main source of anthocyanins, although they are present in vegetables, roots, bulbs, fruit pulps, pulses and cereals. Huge diversity of anthocyanins, which can be found in nature makes them very complex and interesting group. In plants anthocyanins are present in the form of heterosides. Aglycone anthocyanins are known as anthocyanins. In nature there is 6 well known anthocyanins: pelargonidin, cyanidin, peonidin, delphinidin, malvidin and petunidin. Pelargonidin as stable anthocyanins is the most frequent in nature. The glycoside derivatives of the most widespread in nature are 3-monoside, 3.5 and 3.7 biosides. Interest for anthocyanins is growing over the past few years due to their potential applications in the pharmaceutical industry, the food and cosmetic industries. Despite their great potential, their use is still limited because of their relative instability and the low percentage of extracting from the plant material. Anthocyanins are quite reactive and unstable compounds. They transform reversibly with pH changes. pH is defined as the greatest cause of instability of anthocyanins, and has the greatest impact on colour. Anthocyanins are polar molecules and the most efficient solvent for extraction are the mixture of polar solvent such as ethanol, methanol and acetone. Extraction methods for anthocyanins isolation are not selective because solvents extracted anthocyanins with ballast and the great number of substances such as sugars and organic acids. Because of that, it is necessary to implement a new purification techniques, such as solid phase extraction (SPE), liquid-liquid extraction (LLE), countercurrent chromatography (CCC), and high performance liquid chromatography (HPLC). Identification of anthocyanins play a key role in the taxonomy and evaluate the quality of herbal drugs and foods containing anthocyanins. Reversed phase RP- HPLC connected to a photodiode (DAD detector) is the most used method for detection and identification of anthocyanins. Sample preparation for HPLC analysis usually involves acid hydrolysis of anthocyanins to release anthocyanidins. Anthocyanins may be quantified using any purified standard, but most commonly used is standard of cyanidin-3-glucoside, and quantification is carried out at a wavelength of 520 nm. The method of choice for the rapid screening of total anthocyanins in vegetables and fruits is spectrophotometric determination at 528 nm, with a controlled pH. This method works very well, when the assessment is required and not the accuracy of the quantification. Anthocyanins are poorly absorbed and metabolised to the same extent as other flavonoids, which are considered to have low bioavailability. Examination of bioavailability for most of the anthocyanins was carried out on animals. Most studies have shown maximum concentration in blood after 15min-2h. Interest in anthocyanins has especially grown in recent years due to their positive effects on health. Anthocyanins are effective for chronic diseases, especially in cardiovascular diseases. Together with the other nutritional ingredients are important because of their antioxidant ability, suggesting their potential application in the prevention of several diseases which are associated with oxidative stress. Some plants with high content of anthocyanins play a role in the prevention of mutagenesis and carcinogenesis as inhibitors. Extracts obtained from berries have the highest potential for the removal free radicals. Antioxidant activity of them is proportional to the content of anthocyanins.Antocijani su grupa od preko 500 različitih jedinjenja koja uzrokuju crvenu, ljubičastu i plavu boju mnogih biljaka, a posebno voća, povrća i žitarica. Antocijani strukturno pripadaju flavonima. Uglavnom se voće smatra glavnim izvorom antocijana, mada su oni prisutni i u povrću, korenju, lukovicama, pulpama plodova, mahunarkama i žitaricama. Ogromna raznovrsnost antocijana koja može da se nađe u prirodi čini ih veoma složenom i interesantnom grupom. U biljnim vrstama su prisutni u vidu heterozida. Aglikoni antocijana poznati su kao antocijanidini, a u prirodi je do sad poznato 6 antocijanidina: pelargonidin, cijanidin, peonidin, delfinidin, petunidin i malvidin. Pelargonidin kao najstabilniji antocijanidin je i najviše zastupljen u prirodi. U glikozidne derivate najviše rasprostranjene u prirodi spadaju 3-monozidi, 3,5 biozidi i 3,7 diglukozidi. Interesovanje za antocijane je sve veće proteklih par godina, zbog njihove potencijalne primene u farmaceutskoj industriji, industriji hrane i kozmetičkoj industriji. Uprkos tome njihova upotreba je i dalje ograničena zbog njihove relativne nestabilnosti i niskom procentu ekstrahovanja iz biljnog materijala. Antocijani su reaktivna i dosta nestabilna jedinjenja. Reverzibilno trpe strukturne transformacije sa promenom pH što ima najveći uticaj na boju. pH je određen kao uzročnik najveće nestabilnosti antocijana, i od pH u najvećoj meri zavisi njihova pigmentacija. Antocijani su polarni molekuli tako da su se kao najefikasniji rastvarači za ekstrakciju pokazale smeše polarnih rastvarača kao što su etanol, metanol i aceton. Metode ekstrakcije koje se koriste za izolovanje antocijana nisu selektivne jer pored antocijana ekstrahuje se i veliki broj balastnih materija kao što su šećeri i organske kiseline. Neophodno je implementirati nove tehnike prečišćavanja, kao što su ekstrakcije na čvrstoj fazi (SPE), ekstrakcije tečno-tečno (LLE), kao i korišćenje sofisticiranih hromatografskih tehnika kao što su protivstrujna hromatografija (CCC), i visoko efikasna tečna hromatografija (HPLC). Identifikacija antocijana ima ključnu ulogu u taksonomiji, i proceni kvaliteta biljnih droga i hrane koja sadrži antocijane. Reverzno fazna RP-HPLC povezana sa fotodiodom (DAD detektor) je najviše korišćena metoda za identifikaciju i određivanje antocijana. Priprema uzoraka za HPLC analizu uglavnom podrazumeva kiselu hidrolizu antocijana da bi se oslobodili antocijanidini. Antocijani mogu biti kvantifikovani preko bilo kog prečišćenog standarda, ali najčešće se kao standard koristi cijanidin-3-glikozid, a kvantifikacija se vrši na talasnoj dužini od 520 nm. Metoda izbora za brz skrining ukupnih antocijana u povrću i voću je spektrofotometrijsko određivanje na 528 nm, pri kontrolisanoj pH. Ova metoda funkcioniše veoma dobro gde je potrebna procena, a ne preciznost kvantifikacije. Antocijani se slabo resorbuju i ne metabolišu se u istom stepenu kao drugi flavonoidi, zbog čega se smatra da imaju malu bioraspoloživost. Ispitivanje bioraspoloživosti antocijana uglavnom je vršeno je na životinjama. Većina studija je pokazala da dostižu maksimalnu koncentraciju u krvi nakon 15 min - 2h. Zainteresovanost za antocijane je posebno porasla poslednjih godina zbog njihovih pozitivnih efekata na zdravlje. Deluju kod hroničnih bolesti, a u prvom redu kod kardiovaskularnih oboljenja. Oni su zajedno sa ostalim flavonoidima važni nutritivni sastojci zbog svojih antioksidativnih sposobnosti, sto ukazuje na njihovu potencijalnu primenu u prevenciji nekoliko bolesti koje su povezane sa oksidativnim stresom. Neke biljke sa visokim sadržajem antocijana imaju ulogu u prevenciji mutageneze i inhibitori su kancerogeneze. Ekstrakti dobijeni iz bobičastog voća imaju najveći potencijal uklanjanja slobodnih radikala i kod njih je antioksidativna aktivnost proporcionalna sadržaju antocijana

Application of gum Arabic in the production of spray-dried chokeberry polyphenols, microparticles characterisation and in vitro digestion method

Due to its high content of phenolics, black chokeberry has been proposed as a health-promoting material, especially use of chokeberry extract as a food or pharmaceuticals. Chokeberry extract was spray-dried using gum Arabic as a carrier. The optimal conditions for the efficient microencapsulation of chokeberry extract using spray-drying technique have been investigated. The aim of our study was to obtain microparticles with the best potential to improve functionality and stability of extracted chokeberry polyphenols, and to investigate the possibility of microbeads to protect active compounds during simulated digestion process. Morphological characteristics of microbeads were analyzed using FTIR and SEM techniques. Zeta potential, particle size and moisture content were determined. Released total phenolics and total anthocyanins content as well as concentration of individual anthocyanins were quantified before and after digestion process. Microparticles exhibited high encapsulation efficiency up to 87%, and high content of released polyphenols was achieved. After in vitro simulated digestion phenolic compounds decreased by 11-24%, exhibited higher protective effect of gum Arabic. Our results showed that chokeberry microparticles obtained by spray drying method could be useful supplements or functional food.

Security Challenges Due to the Appearance of Counterfeit, Fake and Suspicious Items in the Nuclear Supply Chain

Poslednjih godina, usled ekonomske i političke nestabilnosti širom sveta, raste zabrinutost zbog moguće infiltracije falsifikovanih, lažnih i sumnjivih predmeta (FLSPa) u lanac nuklearnog snabdevanja. FLSPi ne prolaze kroz rigorozne procedure kontrole kvaliteta, koje su obavezne za legitimne artikle, tako da mogu odstupati od propisanih specifikacija. Unutar lanca nuklearnog snabdevanja, FLSP mogu umanjiti integritet opreme, sistema, struktura, komponenti ili uređaja koji doprinose nuklearnoj sigurnosti i/ili nuklearnoj bezbednosti. Nenamerno uvođenje ili zlonamerno umetanje FLSPa u nuklearni lanac snabdevanja može dovesti do pojave nuklearnog bezbednosnog događaja. Prevencija i procena rizika su od suštinskog značaja za obuzdavanje sigurnosnih posledica nezakonite trgovine, a tehnologija bi mogla da igra centralnu ulogu u praćenju, u cilju smanjenja resursa dostupnih politički motivisanim i terorističkim akterima. Zbog toga, neophodno je razviti mere za ublažavanje implikacija na nuklearnu bezbednost od FLSP koji su se infiltrirali u lanac nuklearnog snabdevanja, ili u potpunosti sprečiti njihovo uvođenje. Zahtevi za obezbeđenje kontrole kvaliteta za svaku kategoriju dobavljača i klasifikacija kvaliteta nabavljenog artikla ili usluge treba da budu deo FLSP programa i sastavni deo Integrisanog sistema menandžmenta kontrole kvaliteta. Od velike je važnosti izvršiti sveobuhvatan pregled postojećeg međunarodnog zakonodavstva i propisa koji se odnose na FLSP i sagledati proces nabavke u svetlu implikacija FLSP na nuklearnu bezbednost.In recent years, due to economic and political instability around the world, there has been growing concern over the possible infiltration of counterfeit, fraudulent and suspect items (CFSIs) into the nuclear supply chain. CFSIs do not undergo the same rigorous quality assurance procedures as legitimate items, and deviate from prescribed specifications. Within the nuclear supply chain, CFSIs can diminish the integrity of equipment, systems, structures, components or devices that contribute to nuclear safety and/or nuclear security. The inadvertent introduction or malicious insertion of CFSIs within the nuclear supply chain could lead to the occurrence of a nuclear security event. Prevention and risk assessment are essential in containing the security consequences of illicit trade, and technology could play a central role in monitoring – with the aim of reducing the resources available to politically motivated and terrorist actors. Therefore, it is necessary to develop measures to mitigate the nuclear security implications of CFSIs that have infiltrated the nuclear supply chain, or prevent their introduction altogether. Quality Assurance requirements for each supplier category and the quality classification of the procured item or service should be part of CFSI Program as an integral part of the Integrated Management System and Quality Assurance Program. It is of great importance to make comprehensive review of existing international legislations and regulations which refers to CSFIs and to look into procurement process in the light of nuclear security implications of CFSIs.XXXII Simpozijum Društva za zaštitu od zračenja Srbije i Crne Gore, 4-6. oktobar 2023; Budva, Crna GoraProceedings: [https://vinar.vin.bg.ac.rs/handle/123456789/11602

Health Risk Assessment of Particulate Matter Emissions from Natural Gas and Fuel Oil Heating Plants Using Dispersion Modelling

A significant proportion of homes and apartments in Serbia are still reliant on central heating systems during winter months, with about fifty heating plants in operation. Common fuels used in these plants primarily include fossil fuels such as coal, fuel oil, and natural gas. Some of these fuels have a high sulfur content, leading to an increased concentration of sulfur dioxide and particulate matter in the atmosphere (Todorović et al, 2020; Todorović et al, 2021). This study compares and evaluates the environmental impact of the two heating boilers at the Valjevo city (Serbia) heating plant. The AERMOD air dispersion model was used for estimating the concentrations of the various pollutants (Kakosimos et al, 2011; Mokhtar et al, 2014; Shaikh et al, 2020). Onsite emission data were gathered separately for the two heating boilers at the facility fuelled by natural gas and fuel oil, respectively. A combination of topographical and historical meteorological data were used to set up a receptor grid that was exposed to the gas emission in a radius of 10 km. The environmental impact from the fuel oil boiler was shown to be significantly higher than that caused by the natural gas-fuelled boiler. The resulting distribution of pollutant gases and particles showed that the concentration gradient is less inclined towards the city centre and instead spreads eastwards into the surrounding villages. The data were used to evaluate carcinogenic and non-carcinogenic health risks. It was found that the health risk was acceptable for different averaging periods. However, further study is still required in order to properly assess the cumulative health risk generated by other surrounding industries

Ecological and Health Risks Attributed to Rare Earth Elements in Coal Fly Ash

The occurrence and distribution of yttrium and rare earth elements (REYs), along with major elements and heavy metal(loid)s (HMs) in coal fly ash (CFA) from five coal-fired power plants (CFPPs), were analyzed, and the REY-associated ecological and health risks were assessed. The individual REYs in CFA were abundant in the following order: Ce > La > Nd > Y > Pr > Gd > Sm > Dy > Er > Yb > Eu > Ho > Tb > Tm > Lu. The total REY content ranged from 135 to 362 mg/kg, averaging 302 mg/kg. The mean light-to-heavy REY ratio was 4.1, indicating prevalent light REY enrichment in CFA. Significantly positive correlations between the REYs suggested that they coexist and share similar origins in CFA. REYs were estimated to pose low to moderate ecological risks, with risk index (RI) values ranging from 66 to 245. The hazard index (HI) and target cancer risk (TCR) of REYs from CFA, estimated to be higher for children (HIc = 0.15, TCRc = 8.4 × 10−16) than for adults (HIa = 0.017, TCRa = 3.6 × 10−16), were well below the safety limits (HI = 1, TCR = 1.0 × 10−6). However, the danger to human health posed by HMs in the same CFA samples (HIc = 5.74, TCRc = 2.6 × 10−4, TCRa = 1.1 × 10−4) exceeded the safe thresholds (excl. HIa = 0.63). The mean RI and HI attributed to REYs in CFA were 14% and 2.6%, respectively, of the total risks that include HMs