Multisource feedback in medical students' workplace learning in primary health care.

BACKGROUND: In medical students' workplace learning, feedback is important for effective learning regarding communication and clinical skills. The provision of multisource feedback (MSF) in clinical practice with focus on the patient's perspective is rarely addressed in the literature. The overall objective was to explore the experience of MSF in medical students' clinical learning in primary healthcare (PHC). METHODS: In the study, patients provided feedback by use of the Patient Feedback in Clinical Practice (PFCP) questionnaire. By use of adapted PFCP questionnaire versions peers and clinical supervisors provided feedback and students performed a self-evaluation. The MSF learning activity was evaluated using surveys (4-point Likert scale/open-ended questions), (students (n = 26), peers (n = 9) and clinical supervisors (n = 7)). Data were analysed using descriptive and qualitative content analysis. RESULTS: Results (mean 4-point Likert scale) from participants evaluation of the MSF learning activity visualises the value of feedback in terms of patient-centred communication (students 3.50, peers 2.44 and clinical supervisors 3.57), guidance for further training (students 3.14, peers 2.89 and clinical supervisors 3.00) and clarification of pedagogical assignment (students 3.14, peers 2.89 and clinical supervisors 3.00). Thematic analysis of participants' free-text answers in the evaluation surveys resulted in three themes: (1) applicability of the MSF, (2) MSF - collaborative learning process and (3) MSF as a facilitator in students' clinical skills development. The participants experienced that the written MSF provided multi-facetted perspectives, which contributed to students' and peers' clinical and communication learning. MSF experience also enhanced clinical supervisors' feedback regarding communication skills, targeting the supervisors' pedagogical assignment. CONCLUSION: Our findings indicate that MSF provided directly after a patient encounter, using the PFCP questionnaire as feedback provider, could be an adequate learning activity for medical students' workplace learning. The MSF, provided through the PFCP questionnaire, was experienced to neutralise and operationalise the provision of concrete feedback, facilitating peers' learning and clinical supervisors' tuition. The results visualise the importance of patients in MSF, as a valuable resource in students' workplace learning. Our study implies that this learning activity could be an applicable tool to facilitate learning and pedagogic development in clinical education in PHC.

Let's ask the patient - composition and validation of a questionnaire for patients' feedback to medical students.

BACKGROUND: Adequate communication and maintaining a patient-centered approach throughout patient encounters are important skills for medical students to develop. Feedback is often provided by clinical teachers. Patients are seldom asked to provide feedback to students that systematically addresses knowledge and skills regarding communication and patient-centeredness during an encounter. One way for patients to provide feedback to students is through a questionnaire; there is, however, a lack of such validated feedback questionnaires. This study aimed to compose and validate a feedback questionnaire for patients' feedback to medical students regarding students' ability to communicate and apply patient-centeredness in clinical practice. METHOD: This study comprises (a) composition of the questionnaire and (b) validation of the questionnaire. The composition included (1) literature review, (2) selection and composition of items and construction of an item pool, (3) test of items' content, and (4) test of the applicability of the questionnaire. The items originated from the Calgary-Cambridge Guide (Kurtz S, Silverman J, Benson J and Draper J, Acad Med 78:802-809, 2003), the 'Swedish National Patient Survey' (National Patient Survey, Primary Health Care, 2020), patient evaluation form by Braend et al. (Tidsskr Nor Laegeforen 126:2122-5, 2006), and additional developed items. The items were further developed after feedback from 65 patients, 22 students, eight clinical supervisors, and six clinical teachers. The validation process included 246 patients who provided feedback to 80 students. Qualitative content analysis and psychometric methods were used and exploratory factor analysis assessed internal validity. Cronbach's alpha was used to test the reliability of the items. RESULTS: The process resulted in the 19-item 'Patient Feedback in Clinical Practice' (PFCP) questionnaire. Construct validity revealed two dimensions: consultational approach and transfer of information. Internal consistency was high. Thematic analysis resulted in three themes: ability to capture the personal agenda of the consultation, alignment with the consultation, and constructs and characteristics. Students reported that the PFCP questionnaire provided useful feedback that could facilitate their learning in clinical practice. CONCLUSIONS: The results of this study indicate that the questionnaire is a valid, reliable, and internally consistent instrument for patients' feedback to medical students. The participants found the questionnaire to be useful for the provision of feedback in clinical practice. However, further studies are required regarding the PFCP questionnaire applicability as a feedback tool in workplace learning.

Experiences of a student-run clinic in primary care: a mixed-method study with students, patients and supervisors.

OBJECTIVE: To explore how a student-run clinic (SRC) in primary health care (PHC) was perceived by students, patients and supervisors. DESIGN: A mixed methods study. Clinical learning environment, supervision and nurse teacher evaluation scale (CLES + T) assessed student satisfaction. Client satisfaction questionnaire-8 (CSQ-8) assessed patient satisfaction. Semi-structured interviews were conducted with supervisors. SETTING: Gustavsberg PHC Center, Stockholm County, Sweden. SUBJECTS: Students in medicine, nursing, physiotherapy, occupational therapy and psychology and their patients filled in questionnaires. Supervisors in medicine, nursing and physiotherapy were interviewed. MAIN OUTCOME MEASURES: Mean values and medians of CLES + T and CSQ-8 were calculated. Interviews were analyzed using content analysis. RESULTS: A majority of 199 out of 227 student respondents reported satisfaction with the pedagogical atmosphere and the supervisory relationship. Most of the 938 patient respondents reported satisfaction with the care given. Interviews with 35 supervisors showed that the organization of the SRC provided time and support to focus on the tutorial assignment. Also, the pedagogical role became more visible and targeted toward the student's individual needs. However, balancing the student's level of autonomy and the own control over care was described as a challenge. Many expressed the need for further pedagogical education. CONCLUSIONS: High student and patient satisfaction reported from five disciplines indicate that a SRC in PHC can be adapted for heterogeneous student groups. Supervisors experienced that the SRC facilitated and clarified their pedagogical role. Simultaneously their need for continuous pedagogical education was highlighted. The SRC model has the potential to enhance student-centered tuition in PHC. Key Points Knowledge of student-run clinics (SRCs) as learning environments within standard primary health care (PHC) is limited. We report experiences from the perspectives of students, their patients and supervisors, representing five healthcare disciplines. Students particularly valued the pedagogical atmosphere and the supervisory relationship. Patients expressed high satisfaction with the care provided. Supervisors expressed that the structure of the SRC supported the pedagogical assignment and facilitated student-centered tuition - simultaneously the altered learning environment highlighted the need for further pedagogical education. Student-run clinics in primary health care have great potential for student-regulated learning.

Hydrodynamic modelling of the influence of stormwater and combined sewer overflows on receiving water quality: Benzo(a)pyrene and copper risks to recreational water.

The risk from chemical substances in surface waters is often increased during wet weather, due to surface runoff, combined sewer overflows (CSOs) and erosion of contaminated land. There are strong incentives to improve the quality of surface waters affected by human activities, not only from ecotoxicity and ecosystem health perspectives, but also for drinking water and recreational purposes. The aim of this study is to investigate the influence of urban stormwater discharges and CSOs on receiving water in the context of chemical health risks and recreational water quality. Transport of copper (Cu) and benzo[a]pyrene (BaP) in the Göta River (Sweden) was simulated using a hydrodynamic model. Within the 16 km modelled section, 35 CSO and 16 urban stormwater point discharges, as well as the effluent from a major wastewater treatment plant, were included. Pollutant concentrations in the river were simulated for two rain events and investigated at 13 suggested bathing sites. The simulations indicate that water quality guideline values for Cu are exceeded at several sites, and that stormwater discharges generally give rise to higher Cu and BaP concentrations than CSOs. Due to the location of point discharges and the river current inhibiting lateral mixing, the north shore of the river is better suited for bathing. Peak concentrations have a short duration; increased concentrations of the pollutants may however be present for several days after a rain event. Monitoring of river water quality indicates that simulated Cu and BaP concentrations are in the same order of magnitude as measured concentrations. It is concluded that hydrodynamic modelling is a useful tool for identifying suitable bathing sites in urban surface waters and areas of concern where mitigation measures should be implemented to improve water quality.

Adsorption of organic stormwater pollutants onto activated carbon from sewage sludge.

Adsorption filters have the potential to retain suspended pollutants physically, as well as attracting and chemically attaching dissolved compounds onto the adsorbent. This study investigated the adsorption of eight hydrophobic organic compounds (HOCs) frequently detected in stormwater - including four polycyclic aromatic hydrocarbons (PAHs), two phthalates and two alkylphenols - onto activated carbon produced from domestic sewage sludge. Adsorption was studied using batch tests. Kinetic studies indicated that bulk adsorption of HOCs occurred within 10 min. Sludge-based activated carbon (SBAC) was as efficient as tested commercial carbons for adsorbing HOCs; adsorption capacities ranged from 70 to 2800 µg/g (Cinitial = 10-300 µg/L; 15 mg SBAC in 150 mL solution; 24 h contact time) for each HOC. In the batch tests, the adsorption capacity was generally negatively correlated to the compounds' hydrophobicity (log Kow) and positively associated with decreasing molecule size, suggesting that molecular sieving limited adsorption. However, in repeated adsorption tests, where competition between HOCs was more likely to occur, adsorbed pollutant loads exhibited strong positive correlation with log Kow. Sewage sludge as a carbon source for activated carbon has great potential as a sustainable alternative for sludge waste management practices and production of a high-capacity adsorption material.

Sorption of DOM and hydrophobic organic compounds onto sewage-based activated carbon.

Treatment of stormwater via sorption has the potential to remove both colloidal and dissolved pollutants. Previous research shows that activated carbon produced from sewage sludge is very efficient in sorbing hydrophobic organic compounds (HOCs), frequently detected in stormwater. The aim of this research was to determine whether the presence of dissolved organic matter (DOM) has a negative effect on the adsorption of HOCs onto sludge-based activated carbon (SBAC) in batch adsorption tests. Batch adsorption tests were used to investigate the influence of two types of DOM - soil organic matter and humic acid (HA) technical standard - on the sorption of HOCs onto SBAC, and whether preloading adsorbent and adsorbates with DOM affects HOC sorption. The results indicate that soil DOM and HAs do not have a significant negative effect on the adsorption of HOCs under tested experimental conditions, except for a highly hydrophobic compound. In addition, preloading SBAC or HOCs with DOM did not lead to lower adsorption of HOCs. Batch adsorption tests appear to be inefficient for investigating DOM effects on HOC adsorption, as saturating the carbon is difficult because of high SBAC adsorption capacity and low HOC solubility, so that limited competition occurs on the sorbent.

Evaluation of low-cost materials for sorption of hydrophobic organic pollutants in stormwater.

Conventional stormwater treatment techniques such as sedimentation and filtration are inefficient for removing the dissolved and colloidal phases of hydrophobic organic compounds (HOCs) present in stormwater. Adsorption could be a promising technique for removing colloidal and dissolved pollutants. Five low-cost sorbent materials were investigated in this project, including two minerals ­ vermiculite and perlite ­ and three waste products ­ two pine barks and a sawdust ­ as potential adsorbents for removal of polycyclic aromatic hydrocarbons (PAHs), alkylphenols and phthalates; HOCs commonly found in stormwater. Adsorption capacity and kinetics were studied through batch adsorption tests using synthetic stormwater spiked with a mixture of HOCs. Vermiculite and perlite exhibited insignificant removal of the organic contaminants. The three wood-based materials retained >80% of the initial HOC concentration (10-300 µg/L). The two barks exhibited slightly higher adsorption capacities of HOCs than the sawdust. For all compounds tested, maximum adsorption onto the wood-based media was reached in <10 min. The highest adsorption capacity was found for PAHs (up to 45 µg/g), followed by alkylphenols and phthalates. No correlation was found between adsorption capacity and physical-chemical parameters such as solubility and partition coefficients (log K(ow)). Agreement between empirical data and the pseudo-second order kinetic model suggest chemisorption of HOCs onto a monolayer on wood-based media. This could lead to early saturation of the materials and should be investigated in future studies through repeated adsorption of HOCs, for example in column studies.

Virtual patients in primary care: developing a reusable model that fosters reflective practice and clinical reasoning.

BACKGROUND: Primary care is an integral part of the medical curriculum at Karolinska Institutet, Sweden. It is present at every stage of the students' education. Virtual patients (VPs) may support learning processes and be a valuable complement in teaching communication skills, patient-centeredness, clinical reasoning, and reflective thinking. Current literature on virtual patients lacks reports on how to design and use virtual patients with a primary care perspective. OBJECTIVE: The objective of this study was to create a model for a virtual patient in primary care that facilitates medical students' reflective practice and clinical reasoning. The main research question was how to design a virtual patient model with embedded process skills suitable for primary care education. METHODS: The VP model was developed using the Open Tufts University Sciences Knowledgebase (OpenTUSK) virtual patient system as a prototyping tool. Both the VP model and the case created using the developed model were validated by a group of 10 experienced primary care physicians and then further improved by a work group of faculty involved in the medical program. The students' opinions on the VP were investigated through focus group interviews with 14 students and the results analyzed using content analysis. RESULTS: The VP primary care model was based on a patient-centered model of consultation modified according to the Calgary-Cambridge Guides, and the learning outcomes of the study program in medicine were taken into account. The VP primary care model is based on Kolb's learning theories and consists of several learning cycles. Each learning cycle includes a didactic inventory and then provides the student with a concrete experience (video, pictures, and other material) and preformulated feedback. The students' learning process was visualized by requiring the students to expose their clinical reasoning and reflections in-action in every learning cycle. Content analysis of the focus group interviews showed good acceptance of the model by students. The VP was regarded as an intermediate learning activity and a complement to both the theoretical and the clinical part of the education, filling out gaps in clinical knowledge. The content of the VP case was regarded as authentic and the students appreciated the immediate feedback. The students found the structure of the model interactive and easy to follow. The students also reported that the VP case supported their self-directed learning and reflective ability. CONCLUSIONS: We have built a new VP model for primary care with embedded communication training and iterated learning cycles that in pilot testing showed good acceptance by students, supporting their self-directed learning and reflective thinking.

Metals and trace element concentrations in breast milk of first time healthy mothers: a biological monitoring study.

BACKGROUND: Breast milk is the best source of nutrition for the newborn infant. However, since all infants cannot be breast-fed, there is a need for background data for setting adequate daily intakes. Previously, concentration data on major essential elements and some toxic elements in breast milk, based on different analytical techniques, have been published. There is no recent study on a large number of metals and trace elements in breast milk, using a sensitive analytical method for determination of low element concentrations. METHODS: Breast milk concentrations of 32 metals and elements in early lactation (days 14-21) were determined in a random sample of first time Swedish mothers (n = 60) using inductively coupled plasma mass spectrometry (ICPMS). RESULTS: There were small inter-individual concentration variations in the macroelements Ca, K, Mg, P and S, and striking similarities across studies and over time, supporting a tight regulation of these elements in breast milk. Large inter-individual and over time differences were detected for Na concentrations, which may reflect an increase in salt consumption in Swedish women. Large inter-individual differences were also detected for the microelements Co, Cr, Mn and Mo, and the toxic metals As, Cd, Pb, Sb and V. Arsenic and B were positively correlated with fish consumption, indicating influence of maternal intake on breast milk concentrations. Observed differences in breast milk element concentrations across studies and over time could be attributed to the timing of sampling and a general decline over time of lactation (Cu, Fe, Mo, Zn), a possible lack of regulation of certain elements in breast milk (As, B, Co, Mn, Se) and time trends in environmental exposure (Pb), or in some cases to differences in analytical performance (Cr, Fe). CONCLUSIONS: This study provides reliable updated information on a number of metals and elements in breast milk, of which some have not previously been reported.

Evaluating the respiratory bioaccessibility of nickel in soil through the use of a simulated lung fluid.

Simulated lung fluids are solutions designed to mimic the composition of human interstitial lung fluid as closely as possible. Analysis of mineral dusts using such solutions has been used to evaluate the respiratory bioaccessibility of various elements for which solubility in the lungs is a primary determinant of reactivity. The objective of this study was to employ simulated lung fluid analysis to investigate the respiratory bioaccessibility of nickel in soils. Current occupational guidelines in Australia regulate nickel compounds in terms of water solubility, though this may not be an accurate estimation of the total nickel that will dissociate in the lungs. Surface soils were collected from the city of Kalgoorlie in Western Australia, the site of an operational nickel smelter and metal mining activities. The fraction of the samples less than 10 µm was extracted from the soil, and it was this sub-10-µm fraction that was found to hold most of the total nickel present in the soil. The fine fraction was analyzed using a simulated lung fluid (modified Gamble's solution) to isolate the nickel phases soluble in the lungs. In addition, a sequential extraction was employed to compare the bioaccessible fraction to those dissolved from different binding forms in the soil. In all samples, the simulated lung fluid extracted more nickel than the two weakest leaches of the sequential extraction combined, providing a more representative nickel bioaccessibility value than the current water leach method.

Learning from patients' written feedback: medical students' experiences.

METHODS: Fifty-nine medical students evaluated their learning experience of receiving patients' written feedback obtained from the PFCP questionnaire. Students (N = 57) evaluated their experiences by applying a nine-question evaluation survey (Likert scale N = 3 and free-text questions N = 6) and/or participated in a semi-structured interview (N = 6 students). Data were analyzed using descriptive statistics and qualitative content analysis. RESULTS: The analysis of data from the students' evaluation survey was performed using 4-point Likert scale questions presented in mean, SD and range; ability to apply patient-centred communication (3.3, 0.74, 2-4), guidance for further clinical training of clinical skills (3.2, 1.31, 1-4) and visualization of the pedagogical assignment during an encounter (3.0, 1.68, 1-4). A content analysis of the free-text questions from the students' evaluation surveys and interviews resulted in three themes: (1) confidence in clinical practice, (2) application of patient-centred communication and (3) identification of learning needs. CONCLUSIONS: The results indicate that patients' feedback facilitated a reflective self-directed learning process with the identification of learning needs and increased awareness of the patient as a collaborative partner during the encounter. Patients' written feedback adjacent to a patient encounter is identified as a valuable additional learning tool in medical students' workplace learning. Further studies are required to explore how patients' written feedback can be operationalized in different clinical contexts, for example, in in-patient care.

Screening of organic contaminants in urban snow.

Snowmelt is known to cause peak concentrations of pollutants, which may adversely affect receiving water quality. High concentrations of metals and suspended solids in snow have been reported, whereas studies on organic pollutants are rare. This study aims at investigating the occurrence of anthropogenic organic compounds in urban snow in Gothenburg (Sweden). The most frequently detected organic pollutants in the collected snow samples were polycyclic aromatic hydrocarbons (PAHs), high molecular-weight phthalates, 4-nonylphenol and 4-t-octylphenol. Brominated flame retardants and chlorinated paraffins were only sporadically detected. In several snow samples, the concentrations of specific PAHs, alkylphenols and phthalates were higher than reported stormwater concentrations and European water quality standards. Pollutant source identification and sustainable management of snow are important instruments for the mitigation of organic contaminants in the urban environment.

Occupational therapy and physiotherapy students' communicative and collaborative learning in an interprofessional virtual setting.

BACKGROUND: Interprofessional learning activities can contribute to preparing students to function in health care teams. Although the importance of communication is acknowledged, there is still a lack of understanding about how students learn to communicate interprofessionally. AIM: To explore occupational therapist and physiotherapist students learning of skills in interprofessional communication by studying the students' communication while working together with a virtual patient. MATERIAL AND METHODS: The students carried out a virtual patient encounter in pairs of two, using one computer per student, sitting side by side. The students' actions and conversations were recorded as video films, the oral communication was transcribed and analysed using qualitative content analysis. RESULTS: The students created a social learning environment by posing questions, acknowledging each other and clarifying their professional perspective using familiar professional concepts. Comparing their professional views, students related their peers' statements to their own. Departing from their own profession and using the created open environment, the students' communication led to an interprofessional meaning-making process, with students aiming to understand each other. CONCLUSIONS AND SIGNIFICANCE: A reciprocal learning situation was created when students worked together in a virtual setting. Communicating and making shared decisions about a patient can facilitate learning how to communicate interprofessionally and improve students' understanding of their own profession.

Traffic-related microplastic particles, metals, and organic pollutants in an urban area under reconstruction.

In urban environments, particularly areas under reconstruction, metals, organic pollutants (OP), and microplastics (MP), are released in large amounts due to heavy traffic. Road runoff, a major transport route for urban pollutants, contributes significantly to a deteriorated water quality in receiving waters. This study was conducted in Gothenburg, Sweden, and is unique because it simultaneously investigates the occurrence of OP, metals, and MP on roads and in stormwater from an urban area under reconstruction. Correlations between the various pollutants were also explored. The study was carried out by collecting washwater and sweepsand generated from street sweeping, road surface sampling, and flow-proportional stormwater sampling on several occasions. The liquid and solid samples were analyzed for metals, polycyclic aromatic hydrocarbons (PAH), oxy-PAH, aliphatics, aromatics, phthalates, and MP. The occurrence of OP was also analyzed with a non-target screening method of selected samples. Microplastics, i.e. plastic fragments/fibers, paint fragments, tire wear particles (TWP) and bitumen, were analyzed with a method based on density separation with sodium iodide and identification with a stereo microscope, melt-tests, and tactile identification. MP concentrations amounted to 1500 particles/L in stormwater, 51,000 particles/L in washwater, and 2.6 × 106 particles/kg dw in sweepsand. In stormwater, washwater and sweepsand, MP ≥20 µm were found to be dominated by TWP (38%, 83% and 78%, respectively). The results confirm traffic as an important source to MP, OP, and metal emissions. Concentrations exceeding water and sediment quality guidelines for metals (e.g. Cu and Zn), PAH, phthalates, and aliphatic hydrocarbons in the C16-C35 fraction were found in most samples. The results show that the street sweeper collects large amounts of polluted materials and thereby prevents further spread of the pollutants to the receiving stormwater.

Alternative sorption filter materials effectively remove non-particulate organic pollutants from stormwater.

Urban runoff contains a mixture of both particulate and non-particulate organic pollutants (OPs). Hydrophobic OPs such as higher petroleum hydrocarbons, phthalates, and polycyclic organic hydrocarbons (PAHs) are not exclusively bound to particles, but also present in runoff in colloidal and truly dissolved forms. These hydrophobic compounds can also form nano- and microsized emulsions that may carry pollutants in stormwater. Hence, it is of great importance to develop treatment technologies such as sorption filters that can remove non-particulate OPs from contaminated stormwater. A pilot plant using column bed-filters of sand as a pre-filter, in combination with granulated activated carbon, Sphagnum peat or Pinus sylvestris bark, was used to investigate the removal of non-particulate OPs from urban stormwater. Samples from the filter effluents were collected weekly; during or after rain events; and during stress tests when incoming water was spiked with contaminated sediment and petrol or diesel. All sorption filters showed efficient reduction of aliphatic diesel hydrocarbons C16-C35, benzene, and the PAHs phenanthrene, fluoranthene, and pyrene during most of the operation time, which was 18 months. During the stress test events, all sorption filters showed 100% reduction of PAH-16, petrol and diesel aliphatics C5-C35. All sorption filters released DOC and nanoparticles, which may explain some of the transportation of OPs through the filter beds. The recommendation is to use a combination of sand pre-filtration and all the studied sorption materials in stormwater filters in series, to achieve effective removal of different types of OPs. It is also important to improve the hydraulic conditions to obtain sufficient water flows through the filters.

Hydrodynamic modelling of traffic-related microplastics discharged with stormwater into the Göta River in Sweden.

Microplastics (MP) are transported from land-based sources from rivers to marine waters. However, there is currently little knowledge about MP fate from land sources to marine waters. Traffic is estimated to be one of the largest sources of MP; hence, stormwater is expected to be an important transportation route of MP to marine waters. The aim of this study was to investigate the effect of the size and density of tyre wear particles in road run-off on their fate in the Göta River in Sweden using hydrodynamic modelling. The model of the stretch of Göta River, Sweden's largest river, passing through Gothenburg (Sweden's second largest city) and out to the sea, was set up using MIKE 3 FM software. Literature data were used to define the MP characteristics: concentrations in stormwater, prevalent particle sizes, density of MP commonly occurring in road run-off and settling velocities. Results show that higher concentrations of MP are found on the south side of the river, compared with the north side, due to higher annual average daily traffic loads along the south side of the river. The mixing processes in the river and the MP concentrations were generally influenced by the vertical water density gradient caused by saline water from the Kattegat strait. While most MP with higher density and larger size settle in the river, smaller MP with density close to 1.0 g/cm3 do not settle in the river and therefore reach the Kattegat strait and the marine environments. Further research is needed to describe the fate and transport of microplastics in the stormwater system, including treatment facilities, i.e. biofouling, aggregation, degradation and/or further fragmentation and settling.

Organic pollutants, nano- and microparticles in street sweeping road dust and washwater.

Road areas are pollution hotspots where many metals, organic pollutants (OPs) and nano/microparticles accumulate before being transported to receiving waters. Particles on roads originate from e.g. road, tyre and vehicle wear, winter road maintenance, soil erosion, and deposition. Street sweeping has the potential to be an effective and affordable practice to reduce the occurrence of road dust, and thereby the subsequent spreading of pollutants, but there is currently little knowledge regarding its effectiveness. In this paper we investigate the potential of street sweeping to reduce the amounts of OPs and nano/microparticles reaching stormwater, in a case study sampling road dust and washwater from a street sweeping machine, road dust before and after sweeping, and stormwater. The compound groups generally found in the highest concentrations in all matrices were aliphatics C5-C35 > phthalates > aromatics C8-C35 > PAH-16. The concentrations of aliphatics C16-C35 and PAHs in washwater were extremely high at ≤ 53,000 µg/L and ≤ 120 µg/L, respectively, and the highest concentrations were found after a 3-month winter break in sweeping. In general, fewer aliphatic and aromatic petroleum hydrocarbons and PAHs were detected in road dust samples than in washwater. The relative composition of the specific PAH-16 suggests tyre wear, vehicle exhausts, brake linings, motor oils and road surface wear as possible sources. The study indicates that many of the hydrophobic compounds quantified in washwater are attached to small particles or truly dissolved. The washwater contains a wide range of small particles, including nanoparticles in sizes from just below 1 nm up to 300 nm, with nanoparticles in the size range 25-300 nm present in the highest concentrations. The results also indicated agglomeration of nanoparticles in the washwater. The street sweeping collected a large amount of fine particles and associated pollutants, leading to the conclusion that washwater from street sweeping needs to be treated before disposal.

Validity and responsiveness of the test of athletes with knee injuries: the new criterion based functional performance test instrument.

The purpose of this study was to evaluate the validity and responsiveness of the new criterion-based test instrument test for athletes with knee-injuries (TAK) which has been evaluated for reliability in an earlier study. Thirty-five subjects between 18 and 50 years were included in the study. They were all anterior cruciate ligament (ACL)-reconstructed and operated with hamstrings graft. The test-occasions were at 4 and 8 months after operation. The content validity of the TAK was evaluated by determining floor and ceiling effects 4 and 8 months after ACL-operation. Floor or ceiling effects <30% were considered acceptable. The criterion validity was evaluated by implementing correlations between the TAK and the two common used validated and reliable scores, the International Knee Documentation Committee Subjective Knee Form (IKDC) and the Short Form-36 (SF-36). To evaluate the construct validity the performance of the eight tests of the TAK was compared to the performance of the healthy leg that represented normal ability. The hypothesis was that the patient and the physiotherapist who assessed the knee function decreased compared to the healthy leg would have a lower score of the TAK. The responsiveness of the TAK was evaluated by comparing the effect size of the test-instruments between 4 and 8 months after the operation. At 4 months after operation there were no floor or ceiling effects in any of the eight tests in TAK, except in "Test IV-patients' assessment" and in "Test I-physiotherapist's assessment" that both demonstrated a ceiling effects of 31%. At 8 months there were ceiling effects in five of the eight tests in "TAK-patients' assessment" and in all eight tests assessed by the physiotherapist. IKDC/sport activities had ceiling effects in five of the nine activities at 4 months and in all of them at 8 months. SF-36/scale physical functioning had no floor or ceiling effect neither 4 nor 8 months after operation. At 4 months postoperatively the correlation between the TAK/patients' assessment and IKDC/sport activities was moderate (0.59), while the correlation between TAK/physiotherapist's assessment and IKDC/sport activities was low (0.47). At the same test-occasion there were moderate correlations between SF-36/scale physical functioning and TAK/patients' assessment and TAK/physiotherapist's assessment (0.61 and 0.57), respectively. At eight months the correlations were moderate within all areas except between TAK/patients' assessment and IKDC/sport activities where the correlation was high (0.70). Construct validity for TAK was good seeing that all of the tests showed significant differences between the operated and the healthy non-operated leg (P

Generation of nano- and micro-sized organic pollutant emulsions in simulated road runoff.

A wide range of organic pollutants (OPs) are emitted from the road and traffic environment and transported with road runoff to receiving waters. To provide an understanding of the transport routes of OPs in the environment, an investigation was carried out with the aim to determine whether OPs are transported with nano- and microparticles in the form of emulsions. Tests were performed on simulated road runoff, using laboratory prepared mixtures of ultrapure water and specific polycyclic aromatic hydrocarbons (PAHs), alkylphenols (APs) and their ethoxylates (APEOs), phthalates, diesel oil (aliphatic hydrocarbons), with and without addition of humic acid (HA) and iron (Fe) colloids. The samples were analysed directly after mixing and after a few days of stabilisation for particle size distribution (PSD) and concentrations of particles in the size range 10 nm-100 µm, and zeta potential > ±â€¯500 mV. Further, after long-term storage to achieve stabilisation, selected samples were investigated for the PSD and particle concentrations in the ranges 10 nm-2 µm, to determine whether stable emulsions had formed. The following simulation mixtures, both mixed and stabilised, were identified as potential emulsions: diesel, APs and APEOs, diesel with APs and APEOS, phthalates, and a mixture of all OPs with and without colloids. Measurements with the Zetasizer and Nanosight instruments imply that the majority of particles in the samples were found in the nano-range of 30-660 nm respectively, and a smaller portion of particles < 28% also measured with Coulter Counter were found to be micro-sized. Higher concentrations of the smallest nanoparticles were found in the mixture of all OPs without colloids added, than in the OP mixture with colloids added. The results indicate that the addition of colloids favours the formation of larger micro-sized emulsions that may break down with time into nano-sized particles. In the mixed samples, the number of micro-sized particles decreased, while the number of nanoparticles increased; this process may also occur in road runoff transportation systems during heavy rain events. This is the first study to indicate that emulsions of OPs may be formed in road runoff, and that emulsions may act as carriers of OPs in urban stormwater.

Sorption of organic pollutants frequently detected in stormwater: evaluation of five potential sorbents.

Adsorption filtration is one of the most promising techniques for removal of dissolved, colloidal and particulate pollutants from stormwater. The aim of this study was to compare the capacity of five filter materials - cellulose, chitosan, chitosan-covered bark, pine bark and polypropylene/polyethylene (PP/PE) fibres - to sorb organic pollutants frequently detected in stormwater, including polycyclic aromatic hydrocarbons (PAHs), alkylphenols and phthalates. In batch tests, synthetic stormwater spiked with a mixture of the organic compounds was contacted with the materials for up to 24 h. The compounds were then liquid-liquid extracted and analysed using GC-MS. Cellulose and chitosan showed very low sorption capacity for the organic contaminants, whereas >70% of the initial concentration of most tested compounds was removed using PP/PE fibres, and >80% with pine bark and chitosan-covered bark. The highest adsorption capacity was found for PAHs (up to 44 µg/g) using PP/PE fibres and bark. For all tested compounds, maximum sorption was approached within 30 min using these materials.