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  • 1.
    Avagyan, Rozanna
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Bergvall, Christoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Tire tread wear particles in ambient air—a previously unknown source of human exposure to the biocide 2-mercaptobenzothiazole2014Ingår i: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 21, nr 19, s. 11580-11586Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Urban particulate matter (PM), asphalt, and tire samples were investigated for their content of benzothiazole and benzothiazole derivates. The purpose of this study was to examine whether wear particles, i.e., tire tread wear or road surface wear, could contribute to atmospheric concentrations of benzothiazole derivatives. Airborne particulate matter (PM10) sampled at a busy street in Stockholm, Sweden, contained on average 17 pg/m3 benzothiazole and 64 pg/m3 2-mercaptobenzothiazole, and the total suspended particulate-associated benzothiazole and 2-mercaptobenzothiazole concentrations were 199 and 591 pg/m3, respectively. This indicates that tire tread wear may be a major source of these benzothiazoles to urban air PM in Stockholm. Furthermore, 2-mercaptobenzothiazole was determined in urban air particulates for the first time in this study, and its presence in inhalable PM10 implies that the human exposure to this biocide is underestimated. This calls for a revision of the risk assessments of 2-mercaptobenzothiazole exposure to humans which currently is limited to occupational exposure.

  • 2.
    Avagyan, Rozanna
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Thorsen, Gunnar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Östman, Conny
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Determination of benzothiazole and benzotriazole derivates in tire and clothing textile samples by high performance liquid chromatography-electrospray ionization tandem mass spectrometry2013Ingår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1307, s. 119-125Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A high performance liquid chromatography–tandem mass spectrometry method utilizing electrospray ionization in positive and negative mode has been developed for the separation and detection of benzothiazole and benzotriazole derivates. Ultra-sonication assisted solvent extraction of these compounds has also been developed and the overall method demonstrated on a selected clothing textile and an automobile tire sample. Matrix effects and extraction recoveries, as well as linearity and limits of detection have been evaluated. The calibration curves spanned over more than two orders of magnitude with coefficients of correlation R2 > 0.99 and the limits of detection and the limits of quantification were in the range 1.7–58 pg injected and 18–140 pg/g, respectively. The extraction recoveries ranged between 69% and 102% and the matrix effects between 75% and 101%. Benzothiazole and benzotriazole derivates were determined in the textile sample and benzothiazole derivatives determined in the tire sample with good analytical performance.

  • 3. Batistuzzo, S.
    et al.
    de Oliveira Galvão, M. F.
    Duarte, E. S.
    Hoelzemann, J. J.
    Menezes Filho, J.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Dreij, K.
    PAH exposure and relationship between buccal micronucleus cytome assay and urinary 1-hydroxypyrene levels among cashew nut roasting workers2016Ingår i: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 258, s. S223-S224Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The present study conducted the first assessment of the occupational risk associated to artisanal cashew nut roasting by the use of exposure and effect biomarkers, as well as the characterization and dispersion analysis of the released particulate matter (PM). The PM concentrations in the exposed area were higher than in the non-exposed area. Furthermore, in the control area yielded a higher prevalence of coarse particles, while in the exposed area was observed fine particles. The morphological analysis showed a wide variety of particles. Biomass burning tracers K, Cl, S and Ca were the major inorganic compounds and polycyclic aromatic hydrocarbons (PAHs) with mutagenic and carcinogenic potential, such as benzo[a]pyrene, benzo[b]fluoranthene, benzo[a]anthracene, benzo[j]fluoranthene and indeno[1,2,3-c,d]pyrene were the most abundant PAHs. In addition, atmospheric modeling analysis suggest that these particles can reach regions higher than 40 kilometers. Occupational PAH exposure was confirmed by increases in 1-OHP levels in cashew nut workers. The frequencies of BMCyt biomarkers of genotoxic (micronuclei and nuclear bud) and cytotoxic (pyknosis, karyolysis, karyorrhexis and condensed chromatin) were higher in the exposed group (p < 0.0001) compared with the control group. The influence of factors such as age on the micronucleus was evidenced and a correlation between 1-OHP and MN was observed. It was the first study to found a correlation between these types of biomarkers. The uses of exposure and effect biomarkers were therefore efficient in assessing the occupational risk associated with artisanal cashew nut roasting and the high rates of PM2.5 are considered a potential contributor to this effect.

  • 4. de Oliveira Galvão, Marcos Felipe
    et al.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Batistuzzo de Medeiros, Silvia R.
    Dreij, Kristian
    DNA damage signaling and genotoxic effects induced by complex mixtures of PAHs generated by biomass burning air particulate matter in human lung cells2019Ingår i: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 314, nr SI, s. S132-S133Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Most research concerning the effects of air pollutants on human health focuses on urban centers and on the role of vehicular and industrial emissions as major sources of pollution. However, approximately 3 billion people world-wide are exposed to air pollution from biomass burning [1]. Herein, particulate matter (PM) emitted from artisanal cashew nut roasting, an important economic and social activity worldwide [2,3], was investigated. This study focused on: i) chemical characterization of polycyclic aromatic hydrocarbons (PAHs) and their oxy-PAH derivatives; ii) time-dependent activation of DNA damage signaling and genotoxic effects, and iii) differential expression of genes involved in xenobiotic metabolism, inflammation, cell cycle arrest and DNA repair using A549 lung cells. Among the PAHs, chrysene, benzo[a]pyrene (B[a]P), benzo[b]fluoranthene, and benz[a]anthracene showed the highest concentrations (7.8-10 ng/m3), while among oxy-PAHs, benzanthrone and 9,10-anthraquinone were the most abundant. Testing of PM extracts was based on B[a]P equivalent doses (B[a]Peq). IC50 values for viability was 5.7 and 3.0 nM B[a]Peq at 24 h and 48 h, respectively. Based on this, all other experiments were conducted at doses up to 2 nM B[a]Peq. At these low doses, we observed a dose-dependent activation of DNA damage signaling (phosphorylation of Chk1) and genotoxicity (double strand breaks). In comparison, effects of B[a]P alone was observed at micromolar range. To our knowledge, no other study has demonstrated an activation of pChk1, a biomarker used to estimate the carcinogenic potency of PAHs in vitro [4], in lung cells exposed to biomass burning extracts. Persistent increased gene expression of several important stress response mediators of xenobiotic metabolism (CYP1A1, CYP1B1), inflammation (IL-8, TNF-α), cell cycle arrest (CDKN1A), and DNA repair (DDB2) was also identified. In conclusion, our data show high potency of biomass burning PM to induce cellular stress including genotoxicity, and more potently so when compared to B[a]P alone. Our study provides new data that will help elucidate the mechanism of lung cancer development associated with biomass burning. In addition, the results of this study support the establishment of new guidelines for human health protection in regions strongly impacted by biomass burning.

  • 5. de Oliveira Galvão, Marcos Felipe
    et al.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Batistuzzo de Medeiros, Silvia Regina
    Dreij, Kristian
    Genotoxicity and DNA damage signaling in response to complex mixtures of PAHs in biomass burning particulate matter from cashew nut roasting2020Ingår i: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 256, artikel-id 113381Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Approximately 3 billion people world-wide are exposed to air pollution from biomass burning. Herein, particulate matter(PM) emitted from artisanal cashew nut roasting, an important economic activity worldwide, was investigated. This study focused on: i) chemical characterization of polycyclic aromatic hydrocarbons (PAHs) and oxygenated (oxy-) PAHs; ii) intracellular levels of reactive oxygen species (ROS); iii) genotoxic effects and time- and dose-dependent activation of DNA damage signaling, and iv) differential expression of genes involved in xenobiotic metabolism, inflammation, cell cycle arrest and DNA repair, using A549 lung cells. Among the PAHs, chrysene, benzo[a]pyrene (B[a]P), benzo[b]fluoranthene, and benz[a]anthracene showed the highest concentrations (7.8–10 ng/m3), while benzanthrone and 9,10-anthraquinone were the most abundant oxy-PAHs. Testing of PM extracts was based on B[a]P equivalent doses (B[a]Peq). IC50 values for viability were 5.7 and 3.0 nM B[a]Peq at 24 h and 48 h, respectively. At these low doses, we observed a time- and dose-dependent increase in intracellular levels of ROS, genotoxicity (DNA strand breaks) and DNA damage signaling (phosphorylation of the protein checkpoint kinase 1 – Chk1). In comparison, effects of B[a]P alone was observed at micromolar range. To our knowledge, no previous study has demonstrated an activation of pChk1, a biomarker used to estimate the carcinogenic potency of PAHs in vitro, in lung cells exposed to cashew nut roasting extracts. Sustained induction of expression of several important stress response mediators of xenobiotic metabolism (CYP1A1, CYP1B1), ROS and pro-inflammatory response (IL-8, TNF-α, IL-2,COX2), and DNA damage response (CDKN1A and DDB2) was also identified. In conclusion, our data show high potency of cashew nut roasting PM to induce cellular stress including genotoxicity, and more potently when compared to B[a]P alone. Our study provides new data that will help elucidate the toxic effects of low-levels of PAH mixtures from air PM generated by cashew nut roasting.

  • 6.
    Ekner, Holly
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Dreij, Kristian
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Determination of polycyclic aromatic hydrocarbons in commercial olive oils by HPLC/GC/MS – Occurrence, composition and sources2022Ingår i: Food Control, ISSN 0956-7135, E-ISSN 1873-7129, Vol. 132, artikel-id 108528Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Polycyclic aromatic hydrocarbons (PAHs) are a large class of organic compounds produced from incomplete combustion. Many PAHs are mutagenic and some are carcinogenic and pose a health risk to humans. Dietary intake of PAHs is a major route of exposure, where fats and edible oils are important contributors to overall dietary PAH exposure. Composed of hundreds of individual compounds as a complex mixture, only 16 PAHs are typically monitored in food and the environment.

    In this present study we analyzed 16 commercial olive oil samples from different countries of origin and type (virgin or refined oil) for their content of 45 PAHs using a high-performance liquid chromatograph coupled to a gas chromatograph with a mass spectrometric detector. The content of the 45 PAHs varied between 9.17–94.7 μg/kg (median: 30.1 μg/kg) in the different olive oil samples. Only one sample didn't meet the regulatory threshold levels for PAHs.

    The compositional profile of PAHs across the olive oil samples showed a high abundance of PAHs of lower molecular weights, and a large contribution of alkylated PAHs regardless of olive oil type. Direct contact with diesel exhaust emissions from mechanical harvesters has previously shown to affect PAH levels in olive oils. Using diagnostic PAH ratios, biomass/coal combustion and/or petroleum/fossil fuel combustion were indicated as important sources. Source apportionment by positive matrix factorization revealed diesel exhaust emission and biomass combustion as the two major sources of PAHs followed by traffic emissions. This suggests that air quality may have a considerable impact on pollution levels in olive oils and thus indirectly affect dietary exposure.

  • 7.
    Elihn, Karine
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Dalmijn, Joost
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Froment, Jean
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Haland, Alexander
    Johansson, Jana
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Karlsson, Hanna L.
    Martin, Jonathan W.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Mikoviny, Tomas
    Norman, Michael
    Piel, Felix
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK). Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Schlesinger, Daniel
    Silvergren, Sanna
    Vallabani, N. V. Srikanth
    Wisthaler, Armin
    Steimer, Sarah
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Air quality impacts of a large waste fire in Stockholm, Sweden2023Ingår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 315, artikel-id 120124Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Fires in waste facilities are a common occurrence. Since many waste facilities are located adjacent to densely populated areas, these fires could potentially expose large populations to the emitted pollutants. However, at the moment there are only few field studies investigating the impact of waste fire emissions on air quality since the unpredictable nature of these events makes them challenging to capture. This study investigated the impact of a large and persistent un-prescribed fire in a waste storage facility in Stockholm county, Sweden, on the local air quality of two residential areas in close proximity to the fire. In-situ measurements of particulate matter, black carbon and nitrogen oxide concentrations were conducted both during open burning and after the fire was fully covered. In addition, filter samples were collected for offline analysis of organic composition, metal content and toxicity. Strongly increased concentrations of PM10, PM2.5 and black carbon were found during the open burning period, especially when the wind was coming from the direction of the fire. In addition, elevated concentrations of particulate heavy metals and polycyclic aromatic hydrocarbons were observed in the air during the open burning period. These results show that waste fires can have a strong impact on the air quality of nearby residential areas.

  • 8. Felipe de Oliveira Galvão, Marcos
    et al.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Marques Pedro, Tiago
    Dreij, Kristian
    Determination of whole mixture-based potency factors for cancer risk assessment of complex environmental mixtures by in vitro testing of standard reference materials2022Ingår i: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 166, artikel-id 107345Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Whole mixture-based testing using in vitro new approach methodologies (NAMs) has been suggested to facilitate the hazard and risk assessment of complex environmental mixtures. Previous studies have shown that phosphorylation of DNA damage signaling proteins checkpoint kinase 1 (pChk1) and histone 2AX (γH2AX) are sensitive markers that can be used for estimating carcinogenicity potencies in vitro. Here, and with the aim to better validate the applicability, in vitro-based Mixture Potency Factors (MPFs) of Standard Reference Materials (SRMs) from environmental polycyclic aromatic hydrocarbon (PAH)-containing mixtures were determined and compared to published mutagenicity and tumorigenicity data. Also, genotoxicity was assessed by a flow cytometry-based micronucleus (MN) assay which showed that only benzo[a]pyrene (B[a]P) and coal tar SRM (SRM1597a) caused dose-dependent increases of MN formation, while extracts of diesel particulate matter (SRM1650b), diesel particulate extract (SRM1975), and urban dust (SRM1649b) did not. However, a dose-dependent activation of DNA damage signaling was observed for all PAHs and SRMs. The results demonstrated that all SRMs were more potent than B[a]P, at B[a]P-equivalent concentrations, to induce pChk1 and γH2AX, and that western blot was more sensitive than the In-Cell Western assay in detecting their activation in response to these complex mixtures. Relative MPFs, based on dose–response modelling of pChk1 and γH2AX, ranged 113 – 5270 for the SRMs, indicating several orders of magnitude higher genotoxic potential than B[a]P. Moreover, these MPFs were in good agreement with potency values based on published data from Salmonella mutagenicity and in vivo carcinogenicity studies. In conclusion, these comparisons further validate the feasibility of applying in vitro NAMs, such as whole-mixture based MPFs, in cancer risk assessment of complex mixtures.

  • 9. Hunter, Amanda L.
    et al.
    Unosson, Jon
    Bosson, Jenny A.
    Langrish, Jeremy P.
    Pourazar, Jamshid
    Raftis, Jennifer B.
    Miller, Mark R.
    Lucking, Andrew J.
    Boman, Christoffer
    Nyström, Robin
    Donaldson, Kenneth
    Flapan, Andrew D.
    Shah, Anoop SV
    Pung, Louis
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Masala, Silvia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Sandström, Thomas
    Blomberg, Anders
    Newby, David E.
    Mills, Nicholas L.
    Effect of wood smoke exposure on vascular function and thrombus formation in healthy fire fighters2014Ingår i: Particle and Fibre Toxicology, E-ISSN 1743-8977, Vol. 11, artikel-id 62Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background

    Myocardial infarction is the leading cause of death in fire fighters and has been linked with exposure to air pollution and fire suppression duties. We therefore investigated the effects of wood smoke exposure on vascular vasomotor and fibrinolytic function, and thrombus formation in healthy fire fighters.

    Methods

    In a double-blind randomized cross-over study, 16 healthy male fire fighters were exposed to wood smoke (~1 mg/m3 particulate matter concentration) or filtered air for one hour during intermittent exercise. Arterial pressure and stiffness were measured before and immediately after exposure, and forearm blood flow was measured during intra-brachial infusion of endothelium-dependent and -independent vasodilators 4–6 hours after exposure. Thrombus formation was assessed using the ex vivo Badimon chamber at 2 hours, and platelet activation was measured using flow cytometry for up to 24 hours after the exposure.

    Results

    Compared to filtered air, exposure to wood smoke increased blood carboxyhaemoglobin concentrations (1.3% versus 0.8%; P < 0.001), but had no effect on arterial pressure,augmentation index or pulse wave velocity (P > 0.05 for all). Whilst there was a dose-dependent increase in forearm blood flow with each vasodilator (P < 0.01 for all), there were no differences in blood flow responses to acetylcholine, sodium nitroprusside or verapamil between exposures (P > 0.05 for all). Following exposure to wood smoke, vasodilatation tobradykinin increased (P = 0.003), but there was no effect on bradykinin-induced tissue-plasminogen activator release, thrombus area or markers of platelet activation (P > 0.05 for all).

    Conclusions

    Wood smoke exposure does not impair vascular vasomotor or fibrinolytic function, or increase thrombus formation in fire fighters. Acute cardiovascular events following firesuppression may be precipitated by exposure to other air pollutants or through other mechanisms, such as strenuous physical exertion and dehydration.

  • 10.
    Lim, Hwanmi
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    de Oliveira Galvão, Marcos Felipe
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Dreij, Kristian
    Polycyclic aromatic compounds in particulate matter and indoor dust at preschools in Stockholm, Sweden: Occurrence, sources and genotoxic potential in vitro2021Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 755, artikel-id 142709Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Children spend a significant amount of their day in preschool; thus, environmental quality at preschools may have an impact on children’s health. In the present study, we analyzed polycyclic aromatic compounds (PACs), including PAHs, alkylated PAHs and oxygenated PAHs (OPAHs), in indoor and outdoor air particulate matter (PM10) and indoor dust at preschools in Stockholm, Sweden. There were significant correlations between PAC levels in outdoor and indoor PM10, with in general higher PAC levels outdoors. Fluoranthene and pyrene were detected at highest levels in all sample types, although phenanthrene and methylated phenanthrene derivatives also were found at high levels in indoor dust. In addition, the highly carcinogenic PAHs 7H-benzo[c]fluorene, 7,12-dimethylbenz[a]anthracene, benz[j]aceanthrylene, and dibenzo[a,l]pyrene were detected in some samples. Benzanthrone was the most prevalent OPAH in PM10 samples and 9,10-anthraquinone in indoor dust. Based on diagnostic ratios and Positive Matrix Factorization we identified vehicle emission and biomass burning as important PAC sources for all samples analyzed. However, poor correlation between PAC levels in indoor PM10 and indoor dust suggested additional sources for the latter. Measuring activation of DNA damage signaling in human cells exposed to organic extracts of the samples indicated substantial genotoxic potential of outdoor PM10 and indoor dust. Determination of benzo[a]pyrene equivalents demonstrated that the highly potent PAHs benz[j]aceanthrylene and dibenz[a,h]anthracene contributed more than 20% to the total carcinogenic potency of the samples. We conclude that PAC levels at Stockholm preschools are relatively low but that outdoor air quality may impact on the indoor environment.

  • 11. Nielsen, Ingeborg E.
    et al.
    Eriksson, Axel C.
    Lindgren, Robert
    Martinsson, Johan
    Nyström, Robin
    Nordin, Erik Z.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Boman, Christoffer
    Nøjgaard, Jacob K.
    Pagels, Joakim
    Time-resolved analysis of particle emissions from residential biomass combustion – Emissions of refractory black carbon, PAHs and organic tracers2017Ingår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 165, s. 179-190Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Time-resolved particle emissions from a conventional wood stove were investigated with aerosol mass spectrometry to provide links between combustion conditions, emission factors, mixing state of refractory black carbon and implications for organic tracer methods. The addition of a new batch of fuel results in low temperature pyrolysis as the fuel heats up, resulting in strong, short-lived, variable emission peaks of organic aerosol-containing markers of anhydrous sugars, such as levoglucosan (fragment at m/z 60). Flaming combustion results in emissions dominated by refractory black carbon co-emitted with minor fractions of organic aerosol and markers of anhydrous sugars. Full cycle emissions are an external mixture of larger organic aerosol-dominated and smaller thinly coated refractory black carbon particles. A very high burn rate results in increased full cycle mass emission factors of 66, 2.7, 2.8 and 1.3 for particulate polycyclic aromatic hydrocarbons, refractory black carbon, total organic aerosol and m/z 60, respectively, compared to nominal burn rate. Polycyclic aromatic hydrocarbons are primarily associated with refractory black carbon-containing particles. We hypothesize that at very high burn rates, the central parts of the combustion zone become air starved, leading to a locally reduced combustion temperature that reduces the conversion rates from polycyclic aromatic hydrocarbons to refractory black carbon. This facilitates a strong increase of polycyclic aromatic hydrocarbons emissions. At nominal burn rates, full cycle emissions based on m/z 60 correlate well with organic aerosol, refractory black carbon and particulate matter. However, at higher burn rates, m/z 60 does not correlate with increased emissions of polycyclic aromatic hydrocarbons, refractory black carbon and organic aerosol in the flaming phase. The new knowledge can be used to advance source apportionment studies, reduce emissions of genotoxic compounds and model the climate impacts of refractory black carbon, such as absorption enhancement by lensing.

  • 12. Nyström, Robin
    et al.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Ahmed, Trifa Mohammad
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Koegler, Johannes H.
    Blomberg, Anders
    Sandström, Thomas
    Boman, Christoffer
    Physical and chemical properties of RME biodiesel exhaust particles without engine modifications2016Ingår i: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 186, s. 102s. 261-269Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A major contributor to ambient particulate air pollution is exhaust from diesel engines and other vehicles,which can be linked to different adverse health effects. During the last decades, a global drive towardsfinding sustainable and clean bio-based alternative fuels for the transport sector has taken place and biodieselis one of the most established alternatives today. To better assess the overall effects on a publichealth level when introducing biodiesel and other renewable fuels, a better understanding of the detailedexhaust particle properties, is needed. In this work, the physical and chemical properties of biodieselexhaust particles were studied in comparison to standard diesel exhaust emissions, in an existing enginewithout modifications, focusing on particulate carbonaceous matter and PAH/Oxy-PAH as well as fineparticle size distribution. An older off-road engine, produced between 1996 and 2004, was used withthree different fuels/fuel blends; (1) 100 wt% low-sulfur standard petro diesel (SD), (2) 100 wt% rapeseedmethyl ester biodiesel (B100) and (3) a blended fuel – B30 consisting of 30 wt% RME and 70 wt% SD. Thestudy focused mainly on emissions from transient engine operation, but includes also idling conditions.The gaseous emissions measured for the biodiesel fuel were in general in accordance with previousreported data in the literature, and compared to the standard petro diesel the emissions of CO was lowerwhile NOx emissions increased. The particulate mass concentration during transient operation wasalmost halved compared to when petro diesel was used and this was associated with a decrease in averageparticle size. The shift in particle mass and size was associated with a higher fraction of organic matterin general, considerable less PAH’s but a relative higher fraction of Oxy-PAH’s, when shifting frompetro diesel to biodiesel.

  • 13.
    Olsson, Petter
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Holmbäck, Jan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Class separation of lipids and polycyclic aromatic hydrocarbons in normal phase high performance liquid chromatography - A prospect for analysis of aromatics in edible vegetable oils and biodiesel exhaust particulates2014Ingår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1360, s. 39-46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The retention characteristics of the major lipid components in biodiesels and edible oils as well as representative polycyclic aromatic compounds (PAHs) have been investigated on five different normal phase HPLC stationary phases, in order to optimize class separation for an automatized online HPLC cleanup of PAHs prior GC-MS analysis. By stepwise comparison of different hexane/MTBE compositions as mobile phases on cyano-, phenyl-, pentabromobenzyl-, nitrophenyl- and amino- modified silica columns, the capacity and selectivity factors for each analyte and column could be calculated. It was concluded that the most suitable column for backflush isolation of PAHs in biodiesel and edible oil matrices was the pentabromobenzyl-modified silica (PBB). A previously described online HPLC-GC-MS system using the PBB column was then evaluated by qualitative and quantitative analysis of a biodiesel exhaust particulate extract and a vegetable oil reference material. The GC-MS full scan analysis of the biodiesel particulate extract showed that the lipids had been removed from the sample and a fraction containing PAHs and oxygenated derivatives thereof had been isolated. Quantified mass fractions of PAHs of the reference material BCR-458 agreed well for most of the certified PAH mass fractions in the spiked coconut oil reference material.

  • 14.
    Papazian, Stefano
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    D'Agostino, Lisa A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Froment, Jean
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Bonnefille, Bénilde
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Sdougkou, Kalliroi
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Xie, Hongyu
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Athanassiadis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Budhavant, Krishnakant
    Dasari, Sanjeev
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Andersson, August
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Gustafsson, Örjan
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap.
    Martin, Jonathan W.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Stockholms universitet, Science for Life Laboratory (SciLifeLab).
    Nontarget mass spectrometry and in silico molecular characterization of air pollution from the Indian subcontinent2022Ingår i: Communications Earth & Environment, E-ISSN 2662-4435, Vol. 3, nr 1, artikel-id 35Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A combination of high-resolution mass spectrometry and computational molecular characterization techniques can structurally annotate up to 17% of organic compounds in fine particulate matter in highly polluted air sampled in the Maldives. Fine particulate-matter is an important component of air pollution that impacts health and climate, and which delivers anthropogenic contaminants to remote global regions. The complex composition of organic molecules in atmospheric particulates is poorly constrained, but has important implications for understanding pollutant sources, climate-aerosol interactions, and health risks of air pollution exposure. Here, comprehensive nontarget high-resolution mass spectrometry was combined with in silico structural prediction to achieve greater molecular-level insight for fine particulate samples (n = 40) collected at a remote receptor site in the Maldives during January to April 2018. Spectral database matching identified 0.5% of 60,030 molecular features observed, while a conservative computational workflow enabled structural annotation of 17% of organic structures among the remaining molecular dark matter. Compared to clean air from the southern Indian Ocean, molecular structures from highly-polluted regions were dominated by organic nitrogen compounds, many with computed physicochemical properties of high toxicological and climate relevance. We conclude that combining nontarget analysis with computational mass spectrometry can advance molecular-level understanding of the sources and impacts of polluted air.

  • 15.
    Ramzi, Ahmed
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Ahmadi, Hamid
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Nilsson, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    A two-dimensional non-comprehensive reversed/normal phase high-performance liquid chromatography/tandem mass spectrometry system for determination of limonene and linalool hydroperoxides2018Ingår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1566, s. 102-110Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A two-dimensional non-comprehensive high-performance liquid chromatographic (HPLC) system coupled to electrospray ionization tandem mass spectrometry was developed for the determination of skin allergenic hydroperoxides of limonene and linalool. These compounds are some major components behind skin sensitization and contact (skin) allergy to fragrances.

    Fragrance hydroperoxides usually occur in complex compositions, often as constituents of the natural essential oils added to a large number of commercial products. Their similarities to interfering compounds, many with identical elemental composition, make the determination difficult even when using selective detection methods like mass spectrometry. In this work, a first-dimension chromatographic heart-cut isolation of the hydroperoxides on a reversed-phase HPLC system was combined with a second-dimension normal-phase HPLC system for separation of the hydroperoxides. The intersystem transfer was made by trapping the heart-cut fraction on a short graphitized carbon column, exchanging the mobile phase and back-flushing the hydroperoxides into the second dimension.

    Each analysis was performed within 60 min without any pretreatment, except dilution, prior to injection. The obtained instrumental limits of detection (LODs) at a signal-to-noise ratio of 3 were lower than 1.2 ng injected on column and method LODs were below 0.3 ppm. An after-shave product was shown to contain the highest concentrations of the measured hydroperoxides, with 445 ± 23 ppm of total linalool hydroperoxides. This level is likely able to elicit skin reactions in already sensitized individuals.

  • 16.
    Ramzy, Ahmed
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Ahmadi, Hamid
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Nilsson, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    A two-dimensional reversed and normal phase high-performance liquid chromatography/tandem mass spectrometry system for determination of linalool and limonene hydroperoxidesManuskript (preprint) (Övrigt vetenskapligt)
  • 17.
    Ruiz-Caldas, Maria-Ximena
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Carlsson, Josefine
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Jaworski, Aleksander
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Nilsson, Ulrika
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Mathew, Aji P.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Cellulose Nanocrystals from Postconsumer Cotton and Blended Fabrics: A Study on Their Properties, Chemical Composition, and Process Efficiency2022Ingår i: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 10, nr 11, s. 3787-3798Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    From manufacturing to disposal, the textile industry faces multiple challenges to achieve sustainability and reduce its environmental impact. This work investigates the properties and composition of cellulose nanocrystals (CNCs) extracted from clothing waste made of cotton fibers. We isolated CNCs from cotton, polyester/cotton, and acrylic/cotton waste fabrics through acid hydrolysis with sulfuric acid. A yield of 51-62 wt S4, ( co tt on basis) was obtained, and nearly all the polyester and acrylic libers contained in the initial fabrics were recovered in a convenient shape that could allow easier recycling. CNCs extracted from the selected fabrics showed high purity, similar structural, physical, and chemical characteristics, and their properties were comparable to those extracted from virgin sources, although their surface chemistry and elemental composition slightly differed. The chemical components in the waste fabrics and the extracted CNCs were evaluated through a nontarget chromatographic-mass spectrometric screening strategy. Both the recycled textiles and the CNCs contained hundreds of compounds common in postconsumer textiles, including some with health and environmental concerns. However, our initial findings show that their concentrations in the CNCs are negligible. Our results provide insights into the challenges associated with the use of cotton waste textiles for the extraction of cellulose nanoparticles, and into the potential applications of the extracted nanomaterials.

  • 18.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Traffic related air pollution with emphasis on particle associated polycyclic aromatic hydrocarbons: Tire wear and biodiesel exhaust emissions2016Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Particulate matter (PM) is regarded as one of the more important components of air pollution causing adverse health effects. A large group of compounds associated with PM are polycyclic aromatic compounds (PACs) which comprises polycyclic aromatic hydrocarbons (PAHs). Several PACs are known for their mutagenic and carcinogenic properties as well as have the ability to induce oxidative stress.

    With the growing importance of non-exhaust particles relative to vehicular tail-pipe emissions in urban air, it is necessary to investigate the possible contribution of PAHs from the different non-exhaust sources, as these inputs are far less characterized than tail-pipe emissions and their impact on human health is largely unknown.

    In this thesis automobile tires, an important non-exhaust traffic related source to particles, have been investigated for its content of highly carcinogenic dibenzopyrene isomers. In a separate study benzothiazoles, a class of compounds used as vulcanization accelerators in tire manufacture, were determined to evaluate their use as potential markers for tire wear particles in ambient air.

    Analysis of the tires showed a substantial variation in the PAH content between different makes of tires, likewise did the benzothiazoles content vary. By determining benzothiazole in air particles collected at a busy street in Stockholm the tire rubber contribution to airborne particles was estimated to 0.7 and 5.5 % for PM10 and all airborne particles, respectively. Together with the determined content of dibenzopyrenes and the relatively low mass contribution of tire wear to airborne particles in the urban air, estimated in this thesis as well as suggested by the literature, tire wear appears to be a minor traffic related contributor of these PAH compounds in the urban air. Nevertheless, tire wear may be an important source to 2-mercaptobenzothiazole in the urban air.

    Biodiesel, a biofuel produced from plant and animal fats, has been suggested as a suitable replacement for conventional petroleum based diesel fuels. While the majority of studies have focused on health outcomes from petroleum diesel exhaust exposure, human health effects related to biodiesel exhaust exposure is much less investigated.

    Biodiesel exhaust particles have been compared with conventional petroleum diesel by determining >40 PAHs in two separate studies on two different diesel engines, running on neat rapeseed methyl ester (RME), petroleum diesel and a fuel blend of 3:7 RME : petroleum diesel. One of the biodiesel studies also included determination of four oxygenated PAHs (Oxy-PAHs).

    The exhaust from biodiesel combustion differed from petroleum diesel combustion with regards to particle size, number of emitted particles, relative amount of volatile material adsorbed on the particles and emission of particle-associated PAHs and Oxy-PAHs. A portion of these volatile compounds originated from unburned or partially combusted biodiesel fuel, which interfered with the analysis. A sample cleanup method was therefore developed for determination of PAH in lipid rich matrices. Biodiesel combustion produced lower emission of PAHs and Oxy-PAH with the exception of a few PAHs with higher molecular weights. In comparison with petroleum diesel, the biodiesel particles had a higher relative composition of PAHs with more than four rings. 

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  • 19.
    Sadiktsis, Ioannis
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Bergvall, Christoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Johansson, Christer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM). Environment and Health Administration, Stockholm, Sweden.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Automobile Tires-A Potential Source of Highly Carcinogenic Dibenzopyrenes to the Environment2012Ingår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, nr 6, s. 3326-3334Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Eight tires were analyzed for 15 high molecular weight (HMW) polycyclic aromatic hydrocarbons (PAH), using pressurized fluid extraction. The variability of the PAH concentrations determined between different tires was large; a factor of 22.6 between the lowest and the highest. The relative abundance of the analytes was quite similar regardless of tire. Almost all (92.3%) of the total extractable PAH content was attributed to five PAHs: benzo[ghi]perylene, coronene, indeno[1,2,3-cd]pyrene, benzo[e]pyrene, and benzo[a]pyrene. The difference in the measured PAH content between summer and winter tires varied substantially across manufacturers, making estimates of total vehicle fleet emissions very uncertain. However, when comparing different types of tires from the same manufacturer they had significantly (p = 0.05) different PAH content. Previously, there have been no data available for carcinogenic dibenzopyrene isomers in automobile tires. In this study, the four dibenzopyrene isomers dibenzo[a,l]pyrene, dibenzo[a,e]pyrene, dibenzo[a,i]pyrene, and dibenzo[a,h]pyrene constituted <2% of the sum of the 15 analyzed HMW PAHs. These findings show that automobile tires may be a potential previously unknown source of carcinogenic dibenzopyrenes to the environment.

  • 20.
    Sadiktsis, Ioannis
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    de Oliveira Galvão, Marcos Felipe
    Mustafa, Musatak
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Toublanc, Michaël
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Ünlü Endirlik, Burcu
    Silvergren, Sanna
    Johansson, Christer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap. Environment and Health Administration, Sweden.
    Dreij, Kristian
    A yearlong monitoring campaign of polycyclic aromatic compounds and other air pollutants at three sites in Sweden: Source identification, in vitro toxicity and human health risk assessment2023Ingår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 332, artikel-id 138862Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Air pollution is a complex mixture of gases and particulate matter (PM) with local and non-local emission sources, resulting in spatiotemporal variability in concentrations and composition, and thus associated health risks. To study this in the greater Stockholm area, a yearlong monitoring campaign with in situ measurements of PM10, PM1, black carbon, NOx, O3, and PM10-sampling was performed. The locations included an Urban and a Rural background site and a Highway site. Chemical analysis of PM10 was performed to quantify monthly levels of polycyclic aromatic compounds (PACs), which together with other air pollution data were used for source apportionment and health risk assessment. Organic extracts from PM10 were tested for oxidative potential in human bronchial epithelial cells. Strong seasonal patterns were found for most air pollutants including PACs, with higher levels during the winter months than summer e.g., highest levels of PM10 were detected in March at the Highway site (33.2 μg/m3) and lowest in May at the Rural site (3.6 μg/m3). In general, air pollutant levels at the sites were in the order Highway > Urban > Rural. Multivariate analysis identified several polar PACs, including 6H-Benzo[cd]pyren-6-one, as possible discriminatory markers for these sites. The main sources of particulate pollution for all sites were vehicle exhaust and biomass burning emissions, although diesel exhaust was an important source at the Highway site. In vitro results agreed with air pollutant levels, with higher oxidative potential from the winter samples. Estimated lung cancer cases were in the order PM10 > NO2 > PACs for all sites, and with less evident seasonal differences than in vitro results. In conclusion, our study presents novel seasonal data for many PACs together with air pollutants more traditionally included in air quality monitoring. Moreover, seasonal differences in air pollutant levels correlated with differences in toxicity in vitro.

  • 21.
    Sadiktsis, Ioannis
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Koegler, Johannes H.
    Benham, Timothy
    Bergvall, Christoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Particulate associated polycyclic aromatic hydrocarbon exhaust emissions from a portable power generator fueled with three different fuels – A comparison between petroleum diesel and two biodiesels2014Ingår i: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 115, s. 573-580Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The fuel impact on the emission of more than 40 particulate associated polycyclic aromatic hydrocarbons (PAHs) in the molecular weight range 178–302 Da were investigated. The fuels; neat diesel (EN 590), rape seed methyl ester (B100) and a 30% w/w blend thereof (B30) were tested on a portable power generator without any exhaust aftertreatment. Gaseous emissions of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxides (NOx) were measured along with particulate emissions and its size distribution for the different fuels. Collected diesel particles were extracted using pressurized fluid extraction and analyzed using an online hyphenated liquid chromatography–gas chromatography–mass spectrometry system.

    The neat B100 and the B30 fuel produced less CO and total PAHs while the emissions of NOx and particulate matter increased compared with petroleum diesel fuel per kW h. The reduction of PAH emissions of the alternative diesel fuels were 36% and 70% for B30 and B100 respectively. While the PAH profiles for the neat diesel fuel and B30 were similar, the profile of B100 differed in the sense that the emission contained a higher percentage of PAHs with higher molecular weights. The emission of these PAHs was however larger using the neat diesel fuel with the exception for some of these higher molecular weight PAHs of which there was an increased emission using B100. Thermogravimetric analysis revealed that the collected particles from B100 contained a substantial amount of volatile components. A mass spectrometric full scan analysis suggests that these volatile components are in fact unburned or partially-burned fuel constituents.

    It is concluded that the particles originating from biodiesel combustion might be very different from those originating from petroleum diesel combustion which places new demands on the development of measurement methodologies originally developed for particulate emissions from petroleum-based fuels.

  • 22.
    Sadiktsis, Ioannis
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Nilsson, Gertrud
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut. Camfil AB, Research and Development Department, Sweden.
    Johansson, Ulf
    Rannug, Ulf
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för molekylär biovetenskap, Wenner-Grens institut.
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för miljövetenskap och analytisk kemi.
    Removal of polycyclic aromatic hydrocarbons and genotoxic compounds in urban air using air filter materials for mechanical ventilation in buildings2016Ingår i: Science and Technology for the Built Environment, ISSN 2374-474X, Vol. 22, nr 3, s. 346-355Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Humans spend most of their lives in indoor environments; hence, indoor exposure to air pollution may constitute a large part of the total exposure to air pollution. Polycyclic aromatic hydrocarbons are well known for their mutagenicity and carcinogenicity and are ubiquitous in urban environments as a result of combustion from e.g. vehicular traffic. Polycyclic aromatic hydrocarbons associated to air particulate matter in indoor environments originates from several sources including: cooking and heating, outdoor sources, smoking, candle and incense burning. Infiltration has been suspected to be one major source of indoor polycyclic aromatic hydrocarbons. In this study, four different air filter materials intended for mechanical ventilation were tested for their capability to remove particle bound polycyclic aromatic hydrocarbons and other genotoxic compounds from a real urban aerosol. Particles were sampled at two highly trafficked locations in Stockholm using a sampling system capable of sample particles in parallel, thus allowing sampling of filtered and un-filtered air simultaneously. The sampled particles were extracted and analysed for polycyclic aromatic hydrocarbons and the genotoxicity of the organic extract was determined using Ames mutagenicity tests. Each air filters capability of removing polycyclic aromatic hydrocarbons and reducing genotoxic effects was determined by comparing the filtered and un-filtered air samples. The results showed that all air filter materials had the capability of removing polycyclic aromatic hydrocarbons and reduce genotoxic effects downstream the air filter, and that the magnitude of the reduction was correlated with the standardized particulate collection efficiencies of a 0.4 μm particles for the tested air filter materials. However, the filter with the lowest performance did not significantly reduce direct acting mutagens.

  • 23.
    Thewalim, Yasar
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Colmsjö, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Comparing columns for gas chromatography with the two-parameter model for retention prediction2011Ingår i: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1218, nr 31, s. 5305-5310Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The retention times of selected compounds in temperature programmed gas chromatography were predicted using a two-parameter model, on the basis of thermodynamic data obtained from isothermal runs on seven capillary columns, primarily substituted with 5% diphenylsiloxane. The scope for using thermodynamic data obtained from isothermal runs on one column to optimize separation on a different column or a different instrument setup was investigated. Additionally, the predictive utility of thermodynamic data obtained using a DB-5 column that had been in use for three years was compared to that of a new column of the same model. It was found that satisfactory separation could be achieved on one capillary column or instrument setup on the basis of thermodynamic data obtained using a different column or instrument set-up.

  • 24. Unosson, Jon
    et al.
    Kabéle, Mikael
    Boman, Christoffer
    Nyström, Robin
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Westerholm, Roger
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Mudway, Ian S.
    Purdie, Esme
    Raftis, Jennifer
    Miller, Mark R.
    Mills, Nicholas L.
    Newby, David E.
    Blomberg, Anders
    Sandström, Thomas
    Bosson, Jenny A.
    Acute cardiovascular effects of controlled exposure to dilute Petrodiesel and biodiesel exhaust in healthy volunteers: a crossover study2021Ingår i: Particle and Fibre Toxicology, E-ISSN 1743-8977, Vol. 18, nr 1, artikel-id 22Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Air pollution derived from combustion is associated with considerable cardiorespiratory morbidity and mortality in addition to environmental effects. Replacing petrodiesel with biodiesel may have ecological benefits, but impacts on human health remain unquantified.

    The objective was to compare acute cardiovascular effects of blended and pure biodiesel exhaust exposure against known adverse effects of petrodiesel exhaust (PDE) exposure in human subjects.

    In two randomized controlled double-blind crossover studies, healthy volunteers were exposed to PDE or biodiesel exhaust for one hour. In study one, 16 subjects were exposed, on separate occasions, to PDE and 30% rapeseed methyl ester biodiesel blend (RME30) exhaust, aiming at PM10 300 μg/m3. In study two, 19 male subjects were separately exposed to PDE and exhaust from a 100% RME fuel (RME100) using similar engine load and exhaust dilution. Generated exhaust was analyzed for physicochemical composition and oxidative potential. Following exposure, vascular endothelial function was assessed using forearm venous occlusion plethysmography and ex vivo thrombus formation was assessed using a Badimon chamber model of acute arterial injury. Biomarkers of inflammation, platelet activation and fibrinolysis were measured in the blood.

    Results: In study 1, PDE and RME30 exposures were at comparable PM levels (314 ± 27 μg/m3; (PM10 ± SD) and 309 ± 30 μg/m3 respectively), whereas in study 2, the PDE exposure concentrations remained similar (310 ± 34 μg/m3), but RME100 levels were lower in PM (165 ± 16 μg/m3) and PAHs, but higher in particle number concentration. Compared to PDE, PM from RME had less oxidative potential. Forearm infusion of the vasodilators acetylcholine, bradykinin, sodium nitroprusside and verapamil resulted in dose-dependent increases in blood flow after all exposures. Vasodilatation and ex vivo thrombus formation were similar following exposure to exhaust from petrodiesel and the two biodiesel formulations (RME30 and RME100). There were no significant differences in blood biomarkers or exhaled nitric oxide levels between exposures.

    Conclusions: Despite differences in PM composition and particle reactivity, controlled exposure to biodiesel exhaust was associated with similar cardiovascular effects to PDE. We suggest that the potential adverse health effects of biodiesel fuel emissions should be taken into account when evaluating future fuel policies.

  • 25.
    Westerholm, Roger
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Bergvall, Christoffer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Sadiktsis, Ioannis
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för analytisk kemi.
    Johansson, Christer
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för tillämpad miljövetenskap (ITM).
    Stenius, Ulla
    Mätning av starkt carcinogena dibensopyrener i jämförelse med humancarcinogenenbens(a)pyren [B(a)P] i Stockholmsluft från vägtrafik2012Rapport (Övrigt vetenskapligt)
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