Browsing by Subject "PAH"

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  • Vari, Heli; Roslund, Marja; Oikarinen, Sami; Nurminen, Noora; Puhakka, Riikka; Parajuli, Anirudra; Grönroos, Mira; Siter, Nathan; Laitinen, Olli; Hyöty, Heikki; Rajaniemi, Juho; Rantalainen, Anna-Lea; Sinkkonen, Aki; The ADELE Research Group (2021)
    There is evidence that polycyclic aromatic hydrocarbons (PAHs) and human gut microbiota are associated with the modulation of endocrine signaling pathways. Independently, studies have found associations between air pollution, land cover and commensal microbiota. We are the first to estimate the interaction between land cover categories associated with air pollution or purification, PAH levels and endocrine signaling predicted from gut metagenome among urban and rural populations. The study participants were elderly people (65-79 years); 30 lived in rural and 32 in urban areas. Semi-Permeable Membrane devices were utilized to measure air PAH concentrations as they simulate the process of bioconcentration in the fatty tissues. Land cover categories were estimated using CORINE database and geographic information system. Functional orthologues for peroxisome proliferator-activated receptor (PPAR) pathway in endocrine system were analyzed from gut bacterial metagenome with Kyoto Encyclopaedia of Genes and Genomes. High coverage of broad-leaved and mixed forests around the homes were associated with decreased PAH levels in ambient air, while gut functional orthologues for PPAR pathway increased along with these forest types. The difference between urban and rural PAH concentrations was not notable. However, some rural measurements were higher than the urban average, which was due to the use of heavy equipment on active farms. The provision of air purification by forests might be an important determining factor in the context of endocrine disruption potential of PAHs. Particularly broad-leaved forests around homes may reduce PAH levels in ambient air and balance pollution-induced disturbances within commensal gut microbiota. (C) 2020 The Author(s). Published by Elsevier Ltd.
  • Pedersen, Stephan K.; Pedersen, Viktor B.; Kamounah, Fadhil S.; Broløs, Line M.; Baryshnikov, Glib V.; Valiev, Rashid R.; Ivaniuk, Khrystyna; Stakhira, Pavlo; Minaev, Boris; Karaush-Karmazin, Nataliya; Ågren, Hans; Pittelkow, Michael (2021)
    A soluble, green-blue fluorescent, pi-extended azatrioxa[8]circulene was synthesized by oxidative condensation of a 3,6-dihydroxycarbazole and 1,4-anthraquinone by using benzofuran scaffolding. This is the first circulene to incorporate anthracene within its carbon framework. Solvent-dependent fluorescence and bright green electroluminescence accompanied by excimer emission are the key optical properties of this material. The presence of sliding pi-stacked columns in the single crystal of dianthracenylazatrioxa[8]circulene is found to cause a very high electron-hopping rate, thus making this material a promising n-type organic semiconductor with an electron mobility predicted to be around 2.26 cm(2) V-1 s(-1). The best organic light-emitting diode (OLED) device based on the dianthracenylazatrioxa[8]circulene fluorescent emitter has a brightness of around 16 000 Cd m(-2) and an external quantum efficiency of 3.3 %. Quantum dot-based OLEDs were fabricated by using dianthracenylazatrioxa[8]circulene as a host matrix material.
  • Tissari, Jarkko; Väätäinen, Sampsa; Leskinen, Jani; Savolahti, Mikko; Lamberg, Heikki; Kortelainen, Miika; Karvosenoja, Niko; Sippula, Olli (MDPI, 2019)
    Atmosphere 2019; 10(12):775
    Sauna Stoves (SS) are simple wood combustion appliances used mainly in Nordic countries. They generate emissions that have an impact on air quality and climate. In this study, a new measurement concept for comparing the operation, thermal efficiency, and real-life fine particle and gaseous emissions of SS was utilized. In addition, a novel, simple, and universal emission calculation procedure for the determination of nominal emission factors was developed for which the equations are presented for the first time. Fine particle and gaseous concentrations from 10 different types of SS were investigated. It was found that each SS model was an individual in relation to stove performance: stove heating time, air-to-fuel ratio, thermal efficiency, and emissions. Nine-fold differences in fine particle mass (PM1) concentrations, and about 90-fold differences in concentrations of polycyclic aromatic hydrocarbons (PAH) were found between the SS, when dry (11% moisture content) birch wood was used. By using moist (18%) wood, particle number and carbon monoxide concentrations increased, but interestingly, PM1, PAH, and black carbon (BC) concentrations clearly decreased, when comparing to dry wood. E.g., PAH concentrations were 5.5–9.6 times higher with dry wood than with moist wood. Between wood species, 2–3-fold maximum differences in the emissions were found, whereas about 1.5-fold differences were observed between bark-containing and debarked wood logs. On average, the emissions measured in this study were considerably lower than in previous studies and emission inventories. This suggests that overall the designs of sauna stoves available on the market have improved during the 2010s. The findings of this study were used to update the calculation scheme behind the inventories, causing the estimates for total PM emissions from SS in Finland to decrease. However, wood-fired sauna stoves are still estimated to be the highest individual emission source of fine particles and black carbon in Finland.
  • Kuprijanov, Ivan; Väli, Germo; Sharov, Andrey; Berezina, Nadezhda; Liblik, Taav; Lips, Urmas; Kolesova, Natalja; Mannio, Jaakko; Lips, Inga; Junttila, Ville (Macmillan, 2021)
    Marine Pollution Bulletin, 170 (2021), 112642
    Contamination by hazardous substances is one of the main environmental problems in the eastern Gulf of Finland, Baltic Sea. A trilateral effort to sample and analyse heavy metals (HMs), polycyclic aromatic hydrocarbons (PAHs), and organotins from bottom sediments in 2019–2020 were conducted along with harvesting historical data in Russian, Estonian and Finnish waters. We suggest that the input of organotins still occurs along the ship traffic routes. The tributyltin content exceeded the established quality criteria up to more than 300 times. High contamination by PAHs found near the ports, most likely originate from incomplete fuel incineration processes. The Neva River Estuary and Luga Bay might potentially suffer from severe cadmium contamination. The high ecological risk attributed to the HMs was detected at deep offshore areas. The simulated accumulation pattern qualitatively agrees with field observations of HMs in sediments, demonstrating the potential of numerical tools to tackle the hazardous substances problems.
  • Kohl, Lukas; Meng, Meng; de Vera, Joan; Bergquist, Bridget; Cooke, Colin A.; Hustings, Sarah; Jackson, Brian; Chow, Chung-Wai; Chan, Arthur W. H. (2019)
    Wildfires are increasing in prevalence and intensity and emit large quantities of persistent organic and inorganic pollutants. Recent fires have caused elevated concerns that residual pollutants in indoor environments pose a long‐term health hazard to residents, however, to date no studies have investigated how long fire‐derived pollutants are retained in indoor environments. We quantified polycyclic aromatic hydrocarbons (PAHs) and toxic trace elements in ground ashes from the 2016 wildland‐urban interface fires in Fort McMurray (Alberta, Canada) and in house dust from 64 homes. We document residual arsenic pollution from local building fires, but found no evidence that forest fire ash remained in households 14 months after the fire. Overall, house dust pollutant concentrations were equal or lower than in other locations unaffected by wildfires. Given the current and future concerns over wildfire impacts, this study provides importance evidence on the degree of their long‐term effects on the residential environment.
  • Salo, Santeri (Helsingin yliopisto, 2021)
    Työn tavoitteena oli selvittää polttoöljyn suorapolton soveltuvuutta viljankuivaukseen tarkastelemalla kansallista lainsäädäntöä, paloturvallisuusmääräyksiä, elintarvikevaatimuksia, sekä polttotekniikkaa ja palamistulosta. Lisäksi toteutettiin käytännön kuivauskoe tekniikan toimivuuden, sekä mahdollisten haitallisten viljan kontaminaatioiden selvittämiseksi. Suorapolttoinen uuni on rakenteeltaan yksinkertaisempi ja hyötysuhteeltaan lämmönvaihtimella varustettua uunia parempi. Suorapolttoisia uuneja on käytössä viljankuivauksessa Suomessa jo maa- ja nestekaasukäyttöisinä. Lisäksi muualla Euroopassa käytetään suorapolttoisia öljyuuneja. Kirjallisuuden perusteella suorapoltto saattaa kohottaa kuivattavan viljan PAH- ja raskasmetallipitoisuuksia, jos poltin on säädetty ali-ilmalle. Suomen lainsäädännöstä ei löytynyt estettä öljyn suorapolton käytölle. Kuivauskokeessa todettiin tekniikan toimivan hyvin. Koe toteutettiin sekä polttimen optimisäädöillä, että ali-ilmalle säädetyllä polttimella. Vertailuksi otettiin näytteet myös lämmönvaihdinta käyttäen kuivatusta erästä. Viljanäytteistä analysoitiin PAH4-, lyijy- ja kadmiumpitoisuudet. Näytteistä ei havaittu haitallisia määriä edellä mainittuja yhdisteitä. Tutkimuksessa ei löytynyt suorapolton käyttöä estäviä tekijöitä. Tutkimuksen perusteella suorapolttoa voidaan pitää yhtenä vaihtoehtona viljankuivauksen lämmönlähdettä valittaessa myös Suomessa.
  • Näkki, Pinja; Eronen-Rasimus, Eeva Liisa; Kaartokallio, Hermanni; Kankaanpää, Harri; Setälä, Outi; Vahtera, Emil; Lehtiniemi, Maiju (2021)
    Resistant to degradation, plastic litter poses a long-term threat to marine ecosystems. Biodegradable materials have been developed to replace conventional plastics, but little is known of their impacts and degradation in marine environments. A 14-week laboratory experiment was conducted to investigate the sorption of polycyclic aromatic hydrocarbons (PAHs) to conventional (polystyrene PS and polyamide PA) and bio-based, biodegradable plastic films (cellulose acetate CA and poly-L-lactic acid PLLA), and to examine the composition of bacterial communities colonizing these materials. Mesoplastics (1 cm(2)) of these materials were incubated in sediment and seawater collected from two sites in the Gulf of Finland, on the coast of the highly urbanized area of Helsinki, Finland. PS sorbed more PAHs than did the other plastic types at both sites, and the concentration of PAHs was consistently and considerably smaller in plastics than in the sediment. In general, the plastic bacterial biofilms resembled those in the surrounding media (water and/or sediment). However, in the sediment incubations, the community composition on CA diverged from that of the other three plastic types and was enriched with Bacteroidia and potentially cellulolytic Spirochaetia at both sites. The results indicate that certain biodegradable plastics, such as CA, may harbour potential bioplastic-degrading communities and that PAH sorption capacity varies between polymer types. Since biodegradable plastics are presented as replacements for conventional plastics in applications with risk of ending up in the marine environment, the results highlight the need to carefully examine the environmental behaviour of each biodegradable plastic type before they are extensively introduced to the market. (C) 2020 The Author(s). Published by Elsevier B.V.
  • Hokkanen, Mirja (Finnish Food Authority, 2021)
    Finnish Food Authority Research Reports 2/2021
    Polycyclic aromatic hydrocarbon (PAH) contamination in food poses a potential risk to human health. PAHs are formed primarily as a result of incomplete combustion of organic material and can enter the food chain either from the environment or from food manufacturing processes such as smoking, roasting, drying and grilling. As some of them are known to cause cancer, it is important to reduce the PAH levels in foods as low as is reasonably achievable. The European Food Safety Authority (EFSA) has evaluated the sum of PAH4 compounds (=benzo[a]pyrene (BaP), benz[a]anthracene (BaA), chrysene (CHR) and benzo[b] fuoranthene (BbF)) to serve as a suitable indicator of both the occurrence and toxicity of the PAHs. The primary purpose of this dissertation study was to assess for the frst time Finnish children’s potential health risk caused by dietary exposure to PAH4. In order to complete this task, the applied analytical method must be appropriately validated to be able to produce precise occurrence data. In this study, the gas chromatography-tandem mass spectrometry method was successfully validated according to legislative requirements and the occurrence of PAH4 in a wide range of food groups (fsh, meat, fat and oil, bread, cereal and muesli) was determined. Generally, the concentrations of PAH4 in foods were low and below the prevailing maximum levels. That being said, in smoked fsh and meat products, the variation of the detected PAH4 levels was high, up to 200 µg/kg in smoked ham. It appeared that the smoking process was either controlled or not, and the science-based guidance is required to prevent and reduce contamination of PAHs. Therefore, our goal was to investigate the critical smoking factors that afect the PAH4 formation in fsh and meat products in order to provide tools for manufacturers to produce safer smoked products, thereby decreasing human dietary exposure and adverse health efects. Based on our results, indirect smoking, smoking in less than fve hours, optimised smoke generation temperature between 400 and 600 °C and distance more than fve metres between the food and the smoke source led to reduced PAH4 levels in smoked fsh and meat products. This study aimed to gain a better understanding of the potential mutagenicity of the processed foods, and therefore selected fsh and meat products were tested by the Ames test in Salmonella TA 100 and TA 98 strains with or without metabolic activation. The outcome was further compared to the chemical PAH4 analyses. The statistically signifcant mutagenic response was observed in all three lots of smoked Baltic herring, which also indicated higher PAH4 concentrations than other samples. By contrast, the tested meat products were not mutagenic and the corresponding individual PAH4 concentrations were, for the most part, undetectable. Despite the challenges in food mutagenicity testing, our results provided more information on the potential mutagenic activity of various foods. Specifcally, based on our fndings, a combination of both biological assays and chemical analyses can improve the interpretation of the fndings regarding mutagenicity. Lastly, in reference to our primary purpose of considering potential safety concerns of PAH4 in food, Finnish children’s dietary exposure to PAH4 was evaluated by combining the acquired occurrence and food consumption data. Utilising that data, a margin of exposure (MOE) was calculated in order to be used to provide relative indication of the level of health concern and support prioritisation of possible risk management actions. Our results demonstrated that bread, smoked ham, fat and oil and sausage contributed the most to BaP and PAH4 exposure. Even though the mean PAH4 levels in bread were below the limit of detection, its consumption volumes are high, which explains the contribution. Children’s total mean dietary exposure was estimated to BaP 1,500 pg/kg bw/day and to PAH4 8,100 pg/kg bw/day. The total margins of exposure (MOEs) for children were 482,000 for BaP and 42,000 for PAH4. Furthermore, the calculated MOEs for highly exposed children were also above the reference value 10,000, which caused them to be considered of low concern. Taking into account uncertainties and limitations, this study indicated no health risk to Finnish children aged three to six years.
  • Anasonye, Festus; Tammeorg, Priit; Parshintsev, Evgeny; Riekkola, Marja-Liisa; Tuomela, Marja Tuulikki (2018)
    The use of biochar (BC) has been suggested for remediation of contaminated soils. This study aims to investigate the role of microorganisms in sorption of PAH to BC-amended soils. Fungi, especially the wood and litter-degrading fungi, have shown the ability for humification and to degrade recalcitrant molecules, and are thus suitable model organisms. Haplic Arenosol with high organic matter content was chosen to highlight the importance of soil organic matter (SOM) in PAH sorption, possibly to form non-extractable residue. Basidiomycetous fungi Agrocybe praecox and Phanerochaete velutina grown on pine bark were inoculated in organic matter (OM)-rich Haplic Arenosol and OM-poor sandy loam with either BC or chemically activated BC (ABC) and 14C-labelled pyrene for 60 days. Fungi did not mineralize pyrene, but increased sorption up to 47–56% in BC-amended Haplic Arenosol in comparison with controls (13–25%) without a fungus irrespective of the presence of an adsorbent. In OM-poor sandy loam, only 9–12% of pyrene was sorbed to amended soil in the presence of fungus and adsorbent. The results suggest that BC and fungal amendment increased sorption of pyrene, especially to Haplic Arenosol more than by either BC or fungi alone.