Seasonal trends of per- and polyfluoroalkyl substances in river water affected by fire training sites and wastewater treatment plants

Fire-fighting training areas and wastewater treatment plants (WWTPs) are potential sources of per- and polyfluoroalkyl substances (PFASs) to the nearby aquatic environment. This study investigated seasonal variations of PFAS levels in two river catchments in Sweden; one impacted by Stockholm Arlanda Airport (Sites 1 and 2), and the other by WWTPs and a military airport (Uppsala) (Sites 3 and 4). Sigma PFAS concentrations were up to 61 (Sites 1 and 2) and 4 (Sites 3 and 4) times higher compared to the reference site. Distinct different seasonal trends were observed in the two catchments with higher Sigma PFAS concentrations during the high water flow season at Site 1 compared to the low water flow season, whereas Sites 3 and 4 showed an inverse seasonal trend. This demonstrates that the pollution is mobilized during periods of high flow in the first catchment (Stockholm Arlanda Airport), while it is diluted during high flow in the second catchment (Uppsala). Average annual loads for Sigma PFASs were estimated at similar to 5.2 and similar to 3.7 kg yr(-1) for the catchment in Uppsala and Stockholm Arlanda Airport, respectively. Thus, both catchments add PFASs to Lake Malaren, which is Sweden's most important source area for drinking water production

Dispersal of persistent organic pollutants from fiber-contaminated sediments: biotic and abiotic pathways

Purpose Numerous sites contaminated with fiber emissions from pulp and paper industries are found in coastal areas of the Baltic Sea, but there is limited knowledge about the magnitude of dispersal of persistent organic pollutants (POPs) from these anthropogenic, organic-rich sediments called fiberbanks. The aim of this study was to quantify and compare different POP dispersal pathways from such fiberbanks. Dispersal mechanisms studied included abiotic and biotic routes (dissolved in water, particle-bound, and bioaccumulation). Materials and methods Contaminated fibrous sediments located in angstrom ngermanalven River estuary in north-eastern Sweden were studied in sediment types representing different fiber content (i.e., fiberbanks, fiber-rich sediments, and less fiber impacted sediments). Sediment-to-water fluxes of dissolved contaminants (polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and dichlorodiphenyltrichloroethane (DDT)) were measured in situ using benthic flux chambers. Particle resuspension was measured by sampling bottom water, before and after disturbing the sediment surface. Benthic biota was collected to determine the body burden of contaminants and to determine biota-pore water accumulation factors (BAF(PW)) and biota-sediment accumulation factors (BSAFs). In addition, concentrations of dissolved POPs in the water column were measured in field using passive samplers. Instrumental analysis was performed using gas chromatography coupled to a triple quadrupole mass spectrometer (GC-MS/MS). Results and discussion The flux of dissolved sigma(20)PCBs was approximately two times higher from one of the investigated fiberbanks (3.4 ng m(- 2) day(- 1)) compared to the other. The average particle burden of PCBs was also higher at this fiberbank after artificial disturbance (15 ng g(-1) particle), which indicates that larger amounts of contaminants are likely to disperse via particle resuspension from this site compared to the other fiberbank (4.8 ng g(- 1) particle). The difference might be associated with a layer of recently settled minerogenic material that covers one of the fiberbanks, which probably functions as a protective barrier. The lack of benthic biota implies that contaminant release by bioturbation is negligible in the studied fiberbanks. However, benthic biota from fiber-rich sediment showed bioaccumulation and biomagnification of contaminants. Conclusions The importance of diffusive flux from fiberbanks under undisturbed conditions became apparent when the different dispersal pathways were quantified. However, no dispersal pathway could be judged as irrelevant, since even under undisturbed conditions, advective particle transport was significant. Additionally, the uptake by biota and trophic transfer can be considerable. Quantification of dispersal routes and understanding of the relative importance of various pathways is critical for proper risk assessment and management of contaminated sediments

Combining Leaching and Passive Sampling to Measure the Mobility and Distribution between Porewater, DOC and Colloids of Native Oxy-PAHs, N-PACs and PAHs in Historically Contaminated Soil

Different methods to quantify soil porewater concentrations of contaminants will provide different types of information. Passive sampling measurements give freely dissolved porewater concentrations (Cpw,free), while leaching tests provide information on the mobile concentration (Cpw,leach), including contaminants associated with dissolved organic carbon (DOC) and particles/colloids in the porewater. This study presents a novel combination of these two measurements, to study the sorption and mobility of polycyclic aromatic compounds (PACs) to DOC and particulate organic carbon (POC) in 10 historically contaminated soils. The PACs investigated were polycyclic aromatic hydrocarbons (PAHs), oxygenated-PAHs, and nitrogen containing heterocyclic PACs. Observed Cpw,leach was up to 5 orders of magnitude higher than Cpw,free; implying large biases when Cpw,leach is used to assess bioavailability or soil partitioning. Sorption of PACs to DOC and POC was important for the mobility of compounds with log KOW > 4. Average DOC/water-partitioning coefficients (KDOC) correlated well with KOW (log KDOC = 0.89 × log KOW +1.03 (r2 = 0.89)). This relationship is likely more accurate for historically contaminated soils than previously published data, which suffer from artifacts caused by problems in measuring Cpw,free correctly or not using historically contaminated soils. POC/water-partitioning coefficients (KPOC) were orders of magnitude larger than corresponding KDOC, suggesting sorption to mobile particles/colloids is the dominant mechanism for PAC mobility

Re-analysis of organic flame retardants in Swedish rivers

Flame retardants (FRs) are used in everyday products such as furniture and electronics to provide fire protection. The intensive use of FRs has led to their wide spread in the environment. Many chemicals have been found to have bioaccumulative, persistent and toxic properties which have led to a ban of some of these FR compounds based on international agreements. For example, Penta- and octa-polybrominated diphenyl ethers (BDEs) have been included in the Stockholm Convention. However, most FRs are not restricted, and in many cases it is not known to which extent they are used or to which degree they are polluting the environment. The aim of this study was to provide a snapshot of the current FR pollution in Swedish rivers and streams. In total, 25 rivers and streams were sampled along the east coast of Sweden from north to south. The sampling was done in October 2013 and results from this pre-study were presented previously (Ahrens et al. 2014). Since then, the analytical method for FRs has been improved, and here we report on the re-analysis of the extracts from the previous study. In total 61 (including 7 PBDEs, 35 AFRs, 19 OPFRs), mainly novel FRs, were included in the analytical method. The highest number of FRs was detected in Nyköpingsån (22) and Indalsälven (16). The most frequently detected FRs were ∑tris(1,3-dichloroisopropyl) phosphate/tris(2-ethylhexyl) phosphate) (ΣTDCIPP/TEHP, quantified as the sum of both) detected in all 25 samples from north to south, followed by tris(2-chloroethyl) phosphate (TCEP) (detected in 15 samples) and tetrabromobisphenol-A (TBBPA) (detected in 11 samples). The highest FR concentrations were observed in Nyköpingsån, Fyrisån and Indalsälven with ∑FR concentrations of 240, 230 and 140 ng L-1, respectively. It is evident that FR concentrations in general are higher in the south than in the north, likely explained by the higher population density in the south. Daily loads of ∑FRs transported from Swedish rivers into the Baltic Sea were estimated to be in total 15 kg/day. Indalsälven and Nyköpingsån showed highest total daily loads with 5.2 and 4.9 kg/day, respectively. The composition profiles of these two rivers showed a similar pattern with 3,4,5,6-Tetrabromophthalic anhydride (TEBP-Anh, ~30% of the ∑FR), Tetrachlorobisphenol-A (TCBPA, ~23% of the ∑FR) and TBBPA (~30% of the ∑FR) as the major FRs indicating that these are the three main FRs transported into the Baltic Sea from Swedish rivers. Since this study only provides a snapshot of current conditions, care needs to be taken in the interpretation of the results. This type of screening study is, however, useful for getting a general idea on pollution levels and revealing of tentative hot spots. For better insight into the pollution situation, another sampling strategy is neded, e.g. covering longer time periods (and different seasons) and using more frequent sampling or time/flow-proportional sampling

Fate of pharmaceuticals and pesticides in fly larvae composting

A novel and efficient organic waste management strategy currently gaining great attention is fly larvae composting. High resource recovery efficiency can be achieved in this closed-looped system, but pharmaceuticals and pesticides in waste could potentially accumulate in every loop of the treatment system and spread to the environment. This study evaluated the fate of three pharmaceuticals (carbamazepine, roxithromycin, trimethoprim) and two pesticides (azoxystrobin, propiconazole) in a fly larvae composting system and in a control treatment with no larvae. It was found that the half-life of all five substances was shorter in the fly larvae compost (<10% of control) and no bioaccumulation was detected in the larvae. Fly larvae composting could thus impede the spread of pharmaceuticals and pesticides into the environment

Megakaryocytes possess a functional intrinsic apoptosis pathway that must be restrained to survive and produce platelets

Deletion of Bak and Bax, the effectors of mitochondrial apoptosis, does not affect platelet production, however, loss of prosurvival Bcl-xL results in megakaryocyte apoptosis and failure of platelet shedding

Sequence Diversities of Serine-Aspartate Repeat Genes among Staphylococcus aureus Isolates from Different Hosts Presumably by Horizontal Gene Transfer

BACKGROUND: Horizontal gene transfer (HGT) is recognized as one of the major forces for bacterial genome evolution. Many clinically important bacteria may acquire virulence factors and antibiotic resistance through HGT. The comparative genomic analysis has become an important tool for identifying HGT in emerging pathogens. In this study, the Serine-Aspartate Repeat (Sdr) family has been compared among different sources of Staphylococcus aureus (S. aureus) to discover sequence diversities within their genomes. METHODOLOGY/PRINCIPAL FINDINGS: Four sdr genes were analyzed for 21 different S. aureus strains and 218 mastitis-associated S. aureus isolates from Canada. Comparative genomic analyses revealed that S. aureus strains from bovine mastitis (RF122 and mastitis isolates in this study), ovine mastitis (ED133), pig (ST398), chicken (ED98), and human methicillin-resistant S. aureus (MRSA) (TCH130, MRSA252, Mu3, Mu50, N315, 04-02981, JH1 and JH9) were highly associated with one another, presumably due to HGT. In addition, several types of insertion and deletion were found in sdr genes of many isolates. A new insertion sequence was found in mastitis isolates, which was presumably responsible for the HGT of sdrC gene among different strains. Moreover, the sdr genes could be used to type S. aureus. Regional difference of sdr genes distribution was also indicated among the tested S. aureus isolates. Finally, certain associations were found between sdr genes and subclinical or clinical mastitis isolates. CONCLUSIONS: Certain sdr gene sequences were shared in S. aureus strains and isolates from different species presumably due to HGT. Our results also suggest that the distributional assay of virulence factors should detect the full sequences or full functional regions of these factors. The traditional assay using short conserved regions may not be accurate or credible. These findings have important implications with regard to animal husbandry practices that may inadvertently enhance the contact of human and animal bacterial pathogens

The RNA-binding protein SRSF3 has an essential role in megakaryocyte maturation and platelet production

RNA processing is increasingly recognized as a critical control point in the regulation of different hematopoietic lineages including megakaryocytes responsible for the production of platelets. Platelets are anucleate cytoplasts that contain a rich repertoire of RNAs encoding proteins with essential platelet functions derived from the parent megakaryocyte. It is largely unknown how RNA binding proteins contribute to the development and functions of megakaryocytes and platelets. We show that serine-arginine–rich splicing factor 3 (SRSF3) is essential for megakaryocyte maturation and generation of functional platelets. Megakaryocyte-specific deletion of Srsf3 in mice led to macrothrombocytopenia characterized by megakaryocyte maturation arrest, dramatically reduced platelet counts, and abnormally large functionally compromised platelets. SRSF3 deficient megakaryocytes failed to reprogram their transcriptome during maturation and to load platelets with RNAs required for normal platelet function. SRSF3 depletion led to nuclear accumulation of megakaryocyte mRNAs, demonstrating that SRSF3 deploys similar RNA regulatory mechanisms in megakaryocytes as in other cell types. Our study further suggests that SRSF3 plays a role in sorting cytoplasmic megakaryocyte RNAs into platelets and demonstrates how SRSF3-mediated RNA processing forms a central part of megakaryocyte gene regulation. Understanding SRSF3 functions in megakaryocytes and platelets provides key insights into normal thrombopoiesis and platelet pathologies as SRSF3 RNA targets in megakaryocytes are associated with platelet diseases.publishedVersionPeer reviewe

Uncovering the complex genetics of human temperament

Experimental studies of learning suggest that human temperament may depend on the molecular mechanisms for associative conditioning, which are highly conserved in animals. The main genetic pathways for associative conditioning are known in experimental animals, but have not been identified in prior genome-wide association studies (GWAS) of human temperament. We used a data-driven machine learning method for GWAS to uncover the complex genotypic-phenotypic networks and environmental interactions related to human temperament. In a discovery sample of 2149 healthy Finns, we identified sets of single-nucleotide polymorphisms (SNPs) that cluster within particular individuals (i.e., SNP sets) regardless of phenotype. Second, we identified 3 clusters of people with distinct temperament profiles measured by the Temperament and Character Inventory regardless of genotype. Third, we found 51 SNP sets that identified 736 gene loci and were significantly associated with temperament. The identified genes were enriched in pathways activated by associative conditioning in animals, including the ERK, PI3K, and PKC pathways. 74% of the identified genes were unique to a specific temperament profile. Environmental influences measured in childhood and adulthood had small but significant effects. We confirmed the replicability of the 51 Finnish SNP sets in healthy Korean (90%) and German samples (89%), as well as their associations with temperament. The identified SNPs explained nearly all the heritability expected in each sample (37-53%) despite variable cultures and environments. We conclude that human temperament is strongly influenced by more than 700 genes that modulate associative conditioning by molecular processes for synaptic plasticity and long-term memory.Peer reviewe

Child studies multiple – collaborative play for thinking through theories and methods

This text is an exploration of collaborative thinking and writing through theories, methods, and experiences on the topic of the child, children, and childhood. It is a collaborative written text (with 32 authors) that sprang out of the experimental workshop Child Studies Multiple. The workshop and this text are about daring to stay with mess, “un-closure” , and uncertainty in order to investigate the (e)motions and complexities of being either a child or a researcher. The theoretical and methodological processes presented here offer an opportunity to shake the ground on which individual researchers stand by raising questions about scientific inspiration, theoretical and methodological productivity, and thinking through focusing on process, play, and collaboration. The effect of this is a questioning of the singular academic ‘I’ by exploring and showing what a plural ‘I’ can look like. It is about what the multiplicity of voice can offer research in a highly individualistic time. The article allows the reader to follow and watch the unconventional trial-and-error path of the ongoing-ness of exploring theories and methods together as a research community via methods of drama, palimpsest, and fictionary