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  • 1.
    Avagyan, Rozanna
    et al.
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Bergvall, Christoffer
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Tire tread wear particles in ambient air—a previously unknown source of human exposure to the biocide 2-mercaptobenzothiazole2014In: Environmental science and pollution research international, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 21, no 19, p. 11580-11586Article in journal (Refereed)
    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.
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Thorsen, Gunnar
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Östman, Conny
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Determination of benzothiazole and benzotriazole derivates in tire and clothing textile samples by high performance liquid chromatography-electrospray ionization tandem mass spectrometry2013In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1307, p. 119-125Article in journal (Refereed)
    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
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Dreij, K.
    PAH exposure and relationship between buccal micronucleus cytome assay and urinary 1-hydroxypyrene levels among cashew nut roasting workers2016In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 258, p. S223-S224Article in journal (Refereed)
    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
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Batistuzzo de Medeiros, Silvia
    Dreij, Kristian
    Genotoxicity and DNA damage signaling in response to complex mixtures of PAHs in biomass burning particulate matter from cashew nut roasting2019In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424Article in journal (Refereed)
    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.

  • 5. de Oliveira Galvão, Marcos Felipe
    et al.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    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 cells2019In: Toxicology Letters, ISSN 0378-4274, E-ISSN 1879-3169, Vol. 314, no SI, p. S132-S133Article in journal (Refereed)
    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.

  • 6. 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
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Masala, Silvia
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Sandström, Thomas
    Blomberg, Anders
    Newby, David E
    Mills, Nicholas L
    Effect of wood smoke exposure on vascular function and thrombus formation in healthy fire fighters2014In: Particle and Fibre Toxicology, ISSN 1743-8977, E-ISSN 1743-8977, Vol. 11, no 62Article in journal (Refereed)
    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.

  • 7. Nielsen, Ingeborg E.
    et al.
    Eriksson, Axel C.
    Lindgren, Robert
    Martinsson, Johan
    Nyström, Robin
    Nordin, Erik Z.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    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 tracers2017In: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 165, p. 179-190Article in journal (Refereed)
    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.

  • 8. Nyström, Robin
    et al.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Ahmed, Trifa M.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Koegler, Johannes H.
    Blomberg, Anders
    Sandström, Thomas
    Boman, Christoffer
    Physical and chemical properties of RME biodiesel exhaust particles without engine modifications2016In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 186, p. 102p. 261-269Article in journal (Refereed)
    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.

  • 9.
    Olsson, Petter
    et al.
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Holmbäck, Jan
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    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 particulates2014In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1360, p. 39-46Article in journal (Refereed)
    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.

  • 10.
    Ramzi, Ahmed
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Ahmadi, Hamid
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Nilsson, Ulrika
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    A two-dimensional non-comprehensive reversed/normal phase high-performance liquid chromatography/tandem mass spectrometry system for determination of limonene and linalool hydroperoxides2018In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1566, p. 102-110Article in journal (Refereed)
    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.

  • 11.
    Ramzy, Ahmed
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Ahmadi, Hamid
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Nilsson, Ulrika
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    A two-dimensional reversed and normal phase high-performance liquid chromatography/tandem mass spectrometry system for determination of linalool and limonene hydroperoxides.Manuscript (preprint) (Other academic)
  • 12.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Traffic related air pollution with emphasis on particle associated polycyclic aromatic hydrocarbons: Tire wear and biodiesel exhaust emissions2016Doctoral thesis, comprehensive summary (Other academic)
    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. 

  • 13.
    Sadiktsis, Ioannis
    et al.
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Bergvall, Christoffer
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Johansson, Christer
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM). Environment and Health Administration, Stockholm, Sweden.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Automobile Tires-A Potential Source of Highly Carcinogenic Dibenzopyrenes to the Environment2012In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 46, no 6, p. 3326-3334Article in journal (Refereed)
    Abstract [en]

    Eight tires were analyzed for 15 high molecular weight (HMW) polycyclic aromatic hydrocarbons (PAN), using pressurized fluid extraction. The variability of the PAIR 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 PAIR 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.

  • 14.
    Sadiktsis, Ioannis
    et al.
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Koegler, Johannes H.
    Benham, Timothy
    Bergvall, Christoffer
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Particulate associated polycyclic aromatic hydrocarbon exhaust emissions from a portable power generator fueled with three different fuels – A comparison between petroleum diesel and two biodiesels2014In: Fuel, ISSN 0016-2361, E-ISSN 1873-7153, Vol. 115, p. 573-580Article in journal (Refereed)
    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.

  • 15.
    Sadiktsis, Ioannis
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Nilsson, Gertrud
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute. Camfil AB, Research and Development Department, Sweden.
    Johansson, Ulf
    Rannug, Ulf
    Stockholm University, Faculty of Science, Department of Molecular Biosciences, The Wenner-Gren Institute.
    Westerholm, Roger
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Removal of polycyclic aromatic hydrocarbons and genotoxic compounds in urban air using air filter materials for mechanical ventilation in buildings2016In: Science and Technology for the Built Environment, ISSN 2374-474X, Vol. 22, no 3, p. 346-355Article in journal (Refereed)
    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.

  • 16.
    Thewalim, Yasar
    et al.
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Colmsjö, Anders
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Comparing columns for gas chromatography with the two-parameter model for retention prediction2011In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 1218, no 31, p. 5305-5310Article in journal (Refereed)
    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.

  • 17.
    Westerholm, Roger
    et al.
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Bergvall, Christoffer
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Sadiktsis, Ioannis
    Stockholm University, Faculty of Science, Department of Analytical Chemistry.
    Johansson, Christer
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Stenius, Ulla
    Karolinska Institutet, Institutet för miljömedicin (IMM), Biokemisk toxikologi.
    Mätning av starkt carcinogena dibensopyrener i jämförelse med humancarcinogenenbens(a)pyren [B(a)P] i Stockholmsluft från vägtrafik2012Report (Other academic)
1 - 17 of 17
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