Trends in black carbon and size-resolved particle number concentrations and vehicle emission factors under real-world conditions

Krecl, P.; Johansson, C.; Targino, A.C.; Ström, J.; Burman, L.
2017 | Atmos Environ | 165 (155-168)

Kerbside concentrations of NOx, black carbon (BC), total number of particles (diameter > 4 nm) and number size distribution (28–410 nm) were measured at a busy street canyon in Stockholm in 2006 and 2013. Over this period, there was an important change in the vehicle fleet due to a strong dieselisation process of light-duty vehicles and technological improvement of vehicle engines. This study assesses the impact of these changes on ambient concentrations and particle emission factors (EF). EF were calculated by using a novel approach which combines the NOx tracer method with positive matrix factorisation (PMF) applied to particle number size distributions. NOx concentrations remained rather constant between these two years, whereas a large decrease in particle concentrations was observed, being on average 60% for BC, 50% for total particle number, and 53% for particles in the range 28–100 nm. The PMF analysis yielded three factors that were identified as contributions from gasoline vehicles, diesel fleet, and urban background. This separation allowed the calculation of the average vehicle EF for each particle metric per fuel type. In general, gasoline EF were lower than diesel EF, and EF for 2013 were lower than the ones derived for 2006. The EFBC decreased 77% for both gasoline and diesel fleets, whereas the particle number EF reduction was higher for the gasoline (79%) than for the diesel (37%) fleet. Our EF are consistent with results from other on-road studies, which reinforces that the proposed methodology is suitable for EF determination and to assess the effectiveness of policies implemented to reduce vehicle exhaust emissions. However, our EF are much higher than EF simulated with traffic emission models (HBEFA and COPERT) that are based on dynamometer measurements, except for EFBC for diesel vehicles. This finding suggests that the EF from the two leading models in Europe should be revised for BC (gasoline vehicles) and particle number (all vehicles), since they are used to compile national inventories for the road transportation sector and also to assess their associated health effects. Using the calculated kerbside EF, we estimated that the traffic emissions were lower in 2013 compared to 2006 with a 61% reduction for BC (due to decreases in both gasoline and diesel emissions), and 34–45% for particle number (reduction only in gasoline emissions). Limitations of the application of these EF to other studies are also discussed.

Spatial Distributions of DDTs in the Water Masses of the Arctic Ocean

Carrizo, D.; Sobek, A.; Salvado, J.A.; Gustafsson, Ö.
2017 | Environ. Sci. Technol. | 51 (7913-7919)

Supporting variables for biological effects measurements in fish and blue mussel

Hansson, T.; Thain, J.; Martínez-Gómez, C.; Hylland, K.; Gubbins, M.; Balk, L.
2017 | ICES Techniques in Marine Environmental Sciences | 60 (1-22) | ISBN: 978-87-7482-200-4 | Report No: 60

Biological effects measurements in fish and blue mussel are fundamental in marine environmental monitoring. Nevertheless, currently used biomarkers may be confounded by basic physiological phenomena, such as growth, reproduction, and feeding, as well as thereby associated physiological variation. Here, we present a number of supporting variables, which are essential to measure in order to obtain reliable biological effects data, facilitate their interpretation, and make valid comparisons. For fish, these variables include: body weight, body length, condition, gonad maturation status, various somatic indices, age, and growth. For blue mussels, these variables include: volume, flesh weight, shell weight, and condition. Also, grossly visible anomalies, lesions, and parasites should be recorded for both fish and blue mussels. General confounding factors and their effects are described, as well as recommendations for how to handle them.

Validity of serum concentration in exposure assessment to environmental pollutants – a case study of perfluoroalkyl acids in Finnish children

Koponen, J.; Winkens, K.; Airaksinen, R.; Berger, U.; Vestergren, R.; Cousins, I.T.; Karvonen, A.M.; Pekkanen, J.; Kiviranta, H.
2017 | SU

37th International Symposium on Halogenated Persistent Organic Pollutants (POPs) - DIOXIN 2017. | August 21, 2017 | Vancouver, Canada

Vitaminbrist som dödar

2017 | Forskning & Framsteg | 2017 (7) (28-33)

Brist på vitaminet tiamin har orsakat massdöd bland sjöfåglarna. Svensk forskning visar att problemet är mer utbrett än så. Nu gäller det att förstå orsaken.

Quantifying short-chain chlorinated paraffin congener groups by isolating the response factors from deconvolved soft ionization mass spectra.

Yuan B.; Bogdal C.; Berger U.; Gebbink W.; MacLeod M.; Alsberg T.; de Wit C.A.
2017 | Environ. Sci. Technol. | 51 (10633-10641)

Quantifying short-chain chlorinated paraffin congener groups by isolating the response factors from deconvolved soft ionization mass spectra.

Yuan B.; Bogdal C.; Berger U.; Gebbink W.; MacLeod M.; Alsberg T.; de Wit C.A.
2017 | Environ. Sci. Technol. | 51 (10633-10641)

Historical human exposure to perfluoroalkyl acids in the United States and Australia reconstructed from biomonitoring data using population-based pharmacokinetic modelling

Gomis, M.I.; Vestergren, R.; MacLeod, M.; Mueller, J.F.; Cousins, I.T.
2017 | Environ Int | 108 (92-102)

Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ2H analysis

Jorien E. Vonk; Tommaso Tesi; Lisa Bröder; Henry Holmstrand; Gustaf Hugelius; August Andersson; Oleg Dudarev; Igor Semiletov; Örjan Gustafsson
2017 | TC | 11 (1879-1895)

Chemical composition and source analysis of carbonaceous aerosol particles at a mountaintop site in central Sweden

Vera Franke; Paul Zieger; Ulla Wideqvist; Juan Camilo Acosta Navarro; Caroline Leck; Peter Tunved; Bernadette Rosati; Martin Gysel; Matthew Salter; Johan Ström
2017 | Tellus Ser. B-Chem. Phys. Meteorol. | 69 (1)

Biotransformation of 8:2 polyfluoroalkyl phosphate diester in gilthead bream (Sparus aurata)

Itsaso Zabaleta; Ekhine Bizkarguenaga; Urtzi Izagirre; Noelia Negreira; Adrian Covaci; Jonathan P. Benskin; Ailette Prieto; Olatz Zuloaga;
2017 | Sci. Total Environ.

Polyfluoroalkyl phosphate esters (PAPs) are high production volume surfactants used in the food contact paper and packaging industry. PAPs may transform to persistent perfluoroalkyl carboxylic acids (PFCAs) under biotic conditions, but little is known about their fate and behavior in aquatic organisms. Here we report for the first time on the uptake, tissue distribution, and biotransformation of 8:2 polyfluoroalkyl phosphate diester (8:2 diPAP) in fish. Gilt-head bream (Sparus aurata) were dosed via the diet (8:2 diPAP at 29μg/ g) for 7days, during which time 8:2 diPAP and its transformation products were monitored in plasma, liver, muscle, gills, bile and brain. 8:2 diPAP tended to accumulate in liver, plasma and gills, and to a lesser extent in muscle, bile and brain. Several transformation products (observed previously in other organisms) were also observed in most tissues and biofluids, including both saturated and unsaturated fluorotelomer acids (8:2 FTCA, 8:2 FTUCA, 7:3 FTCA), and perfluorooctanoic acid (PFOA). 8:2 FTCA was the major metabolite in all tissues/biofluids, except for bile, where PFOA occurred at the highest concentrations. Unexpectedly high PFOA levels (up to 3.7ng/g) were also detected in brain. Phase II metabolites, which have been reported in fish following exposure to fluorotelomer alcohols, were not observed in these experiments, probably due to their low abundance. Nevertheless, the detection of PFOA indicates that exposure to PAPs may be an indirect route of exposure to PFCAs in fish.

Sea-air exchange patterns along the central and outer East Siberian Arctic Shelf as inferred from continuous CO2, stable isotope and bulk chemistry measurements

Christoph Humborg; Marc C. Geibel; Leif G. Anderson; Göran Björk; Carl-Magnus Mörth; Marcus Sundbom; Brett F. Thornton; Barbara Deutsch; Erik Gustafsson; Bo Gustafsson; Jörgen Ek; Igor P. Semiletov
2017 | Global Biogeochem Cycles | 31 (7) (1173-1193)

This large-scale quasi-synoptic study gives a comprehensive picture of sea-air CO2 fluxes during the melt season in the central and outer Laptev Sea (LS) and East Siberian Sea (ESS). During a 7 week cruise we compiled a continuous record of both surface water and air CO2 concentrations, in total 76,892 measurements. Overall, the central and outer parts of the ESAS constituted a sink for CO2, and we estimate a median uptake of 9.4 g C m−2 yr−1 or 6.6 Tg C yr−1. Our results suggest that while the ESS and shelf break waters adjacent to the LS and ESS are net autotrophic systems, the LS is a net heterotrophic system. CO2 sea-air fluxes for the LS were 4.7 g C m−2 yr−1, and for the ESS we estimate an uptake of 7.2 g C m−2 yr−1. Isotopic composition of dissolved inorganic carbon (δ13CDIC and δ13CCO2) in the water column indicates that the LS is depleted in δ13CDIC compared to the Arctic Ocean (ArcO) and ESS with an offset of 0.5‰ which can be explained by mixing of δ13CDIC-depleted riverine waters and 4.0 Tg yr−1 respiration of OCter; only a minor part (0.72 Tg yr−1) of this respired OCter is exchanged with the atmosphere. Property-mixing diagrams of total organic carbon and isotope ratio (δ13CSPE-DOC) versus dissolved organic carbon (DOC) concentration diagram indicate conservative and nonconservative mixing in the LS and ESS, respectively. We suggest land-derived particulate organic carbon from coastal erosion as an additional significant source for the depleted δ13CDIC.

Contact information

Visiting addresses:

Geovetenskapens Hus,
Svante Arrhenius väg 8, Stockholm

Arrheniuslaboratoriet, Svante Arrhenius väg 16, Stockholm (Unit for Analytical and Toxicological Chemistry)

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Department of Environmental Science and Analytical Chemistry (ACES)
Stockholm University
106 91 Stockholm

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stella.papadopoulou@aces.su.se