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Per- and poly-fluoroalkyl substances (PFASs) are contaminants of emerging concern, yet the understanding of factors that control their leaching and release from contaminated soils remains limited. This study aimed to investigate the impact of dissolved organic carbon (DOC) on the release of PFASs—specifically, perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), and perfluorooctanoic acid (PFOA)from soils contaminated by aqueous film forming foam (AFFF). Batch aqueous leaching experiments were conducted on AFFF-contaminated soils under alkaline solution conditions (pH 9.5, 10.5, and 12) as it enhances leaching of both PFAS and DOC. Leaching of PFOS was significantly increased under alkaline conditions. Although the leaching of PFAS generally increased with pH, PFOS appeared to be more retained under the very alkaline pH conditions used in this study. At the same solution pH, leaching of PFOS and DOC was less in Ca(OH) 2 than in NaOH. The retention of PFOS under these conditions may be attributable to the shielding of the negative charge of the soil components and colloids (e.g., DOC and clay minerals) in the leachates and/or the screening of negative charges on head groups of PFOS due to the high concentration of divalent cations. Solution chemistry affected desorption of PFOS more than PFHxS and PFOA. The study highlights that the influence of DOC on PFAS leaching and transport can be very complex, and depends on leachate chemistry (e.g., pH and cation type), PFAS chemistry, the magnitude of PFAS contamination and factors that influence the solid:liquid partitioning of organic carbon in soil. [Display omitted] • DOC affects PFAS leaching; impact varies with PFAS concentration & leachate chemistry. • Effect of DOC and solution chemistry on PFAS leaching is more pronounced for PFOS. • Increasing cation concentrations reduces PFAS mobility in environments at high pH. • Cations can decrease the leaching of PFAS at high pH via charge screening. • DOC has a small effect on PFOS desorption from highly contaminated soils. [ABSTRACT FROM AUTHOR]

Many ATP-binding cassette (ABC) transporters regulate channel activity irrespective of their normal transporter/channel activity, and in some cases they also regulate membrane-associated proteins. The physiological aspects of these regulatory events signify the need of tracing the mechanism of these regulatory phenomenon. The regulatory function of the Cl(super -) channel cystic fibrosis transmembrane gene product, CFTR is discussed.

The nature of the lipid influences the transmembrane translocation of lipids while the transmembrane fatty acid distribution depende on pH gradients across the membrane. Facilitated processes participate in fatty acid uptake into cells. The gene product, called FATP for fatty acid transport protein, is a 71 kDa located in plasma membrane. In charged lipids, the polar head group limits passage through the hydrophobic lipid bilayer. The movement of such lipids across the membrane is enabled by proteins. The human multidrug-resistant P-glycoprotein encoded by the MDR1 gene is an active transporter that mediates, MDR2.

Abstract The economies of scale and network effects from agglomeration form the foundation of the economic geography of cities. These agglomerations can be associated with transportation accessibility benefits and negative externalities from increased levels of harmful emissions, both of which are impacted by congestion. Such factors imply a tension between the economies and diseconomies of agglomeration in cities. This research employs real estate transaction data to examine whether spatial trade-offs occur between the benefits and negative impacts of agglomeration in the single-detached property market around two highways in Hamilton, Canada. Our novel disaggregate approach operationalizes agglomeration using empirical estimates of accessibility to employment with calibrated impedance functions; micro-scale dispersion modelling of harmful emissions of particulate matter (PM 2.5); and congestion effects in each. Descriptive analyses reveal areas of transport advantage and environmental disadvantage and cross-sectional spatio-temporal hedonic models find evidence of an agglomeration trade-off in the study area. Results suggest that households value high levels of accessibility in locations that do not experience the corresponding environmental costs from traffic. In contrast, for locations with high access and high exposure, the access benefits of agglomeration are offset by environmental costs. This approach can be used to examine the dynamics of locational advantage, spatial justice, and how trade-offs between the economies and diseconomies of urban agglomeration inform the urban spatial structure of cities. [ABSTRACT FROM AUTHOR]

Abstract Urban development has led to an increase in urban runoff, accompanied with a decrease in water quality during rain events. One of the major causes of the decrease in water quality is the presence of trace organic contaminants in urban runoff. However, little is known about the sources of organic contaminants in urban runoff, especially related to land-use and temporal trends in those associated land uses. The objective of this study was to assess the occurrence and concentration trends of organic contaminants for a high-density residential site and commercial strip site in Madison, WI. Flow-weighted samples of urban stormwater runoff, collected with an auto-sampler, were composited and analyzed, producing mean organic contaminants concentrations for each storm event. The contaminants, which include pesticides, flame retardants, polycyclic aromatic hydrocarbons, corrosion inhibitors, among others, were extracted and analyzed by gas chromatography coupled with mass spectrometry or liquid chromatography coupled with tandem mass spectrometry. There were 30 organic contaminants that had greater than 50% detections in at least one of the sites, and those organic contaminants did provide information on similarities and differences of organic contaminants in urban runoff derived from different land uses. The sum of the total measured pesticides showed no significant difference between sites; this was likely due to the considerable green space and associated pesticide use in both sites. However, there were higher total concentrations of organophosphate flame retardants and corrosion inhibitors in the residential site. The reason for this is unknown and will require follow-up studies; however, several hypotheses are presented. Conversely, there were higher total concentrations of polycyclic aromatic hydrocarbons in the commercial site; this is most likely due to higher vehicle traffic in the commercial site. These data show that land-use may be important in determining the composition and concentrations of trace organic contaminants in urban stormwater runoff. Graphical abstract Image 1 Highlights • Focus is trace organics in the less-studied dissolved (bioavailable) phase of stormwater. • Wastewater associated compounds often detected in runoff at both sites. • Temporal trends for agricultural-use pesticides in stormwater related to application. • Detections suggest leaching of organic compounds from treated outdoor sources. • Heavier traffic trends with higher concentrations of PAHs, but not other compounds. This is the first study to investigate the role that urban land use plays in the levels of trace organic chemicals in urban stormwater in the U.S. [ABSTRACT FROM AUTHOR]

The study presents a multi-group structural equation modelling exercise to identify differences in the mindset of individuals towards electric vehicles (EVs) across seven vehicle body types in Canada. The study utilizes a sample of 15,392 households and grounds the psychographic orientation of potential EV adopters on an extended version of the Theory of Planned Behaviour. Specifically, the study measures the impact of five latent constructs; environmental concerns, attitude, subjective norm, personal moral norm, and perceived behavioural control on the intention to adopt EVs along with socio-economic-demographic (SED) variables. The results highlight that both attitude and perceived behaviour control are the strongest factors influencing individual intention to adopt EVs. However, the multi-group invariance analysis indicates that the psychographic orientation and the SED traits of potential adopters of different EV body types are significantly different, with particular standouts in the luxury and pickup truck classes. We follow this up with an analysis of mindshare towards EVs over the seven vehicle types. Insights derived from the analysis can help define potential submarkets for EVs and accelerate their adoption. [ABSTRACT FROM AUTHOR]

Little work has accounted for congestion, using data that reflects driving patterns, traffic volume, and speed, to examine the association between traffic emissions and human health. In this study, we performed a health risk assessment of PM 2.5 emissions during congestion periods in the Greater Toronto and Hamilton Area (GTHA), Canada. Specifically, we used a micro-level approach that combines the Stochastic User Equilibrium Traffic Assignment Algorithm with a MOVES emission model to estimate emissions considering congestion conditions. Subsequently, we applied a concentration-response function to estimate PM 2.5 -related mortality, and the associated health costs. Our results suggest that traffic congestion has a substantial impact on human health and the economy in the GTHA, especially at the most congested period (7:00 am). Considering daily mortality, our results showed an impact of 206 (boundary test 95%: 116; 297) and 119 (boundary test 95%: 67; 171) deaths per year (all-cause and cardiovascular mortality, respectively). The economic impact from daily mortality is approximately $1.3 billion (boundary test 95%: 0.8; 1.9), and $778 million (boundary test 95%: 478; 981), for all-cause and cardiovascular mortality, respectively. Our study can guide reliable projections of transportation and air pollution levels, improving the capability of the medical community to prepare for future trends. [ABSTRACT FROM AUTHOR]

Low-income residents are often reliant on public transit for daily travel. In North American cities, they have also historically concentrated in centrally located neighbourhoods with relatively higher levels of transit accessibility. However, during the late 20th and early 21st century, regions have witnessed trends of inner-city neighbourhood change and gentrification and the suburbanization of poverty, raising concerns that low-income residents are disproportionately moving away from relied upon transit service. In this paper, we investigate what occurs when low-income residents change dwellings within a region: do they experience a reduction in their levels of transit accessibility, how does this compare to higher-income movers, and how has this changed over time? We examine this by linking historical transit accessibility measures to annual individual-level panel data representing 20% of tax filers in Toronto, Canada from 1988 to 2018. We then analyze changes in transit accessibility for over 2 million intra-urban movers during this time period via descriptive statistics and regression models to answer whether there are significant differences in individual changes in transit accessibility by income level. We find that low-income residents do, on average, experience reductions in their levels of transit accessibility when moving within the region, suggesting a growth in people at risk of transport poverty. Nevertheless, they do not undergo as great of a reduction in transit accessibility as higher-income movers, although this gap in experienced changes in transit accessibility between higher- and low-income movers is converging over time. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) hold great promise for reducing greenhouse gas emissions, yet achieving their environmental benefits depends on greater market uptake. While a growing body of literature has sought to offer information on consumer stated preferences for EVs, to date no research has examined how preferences for hybrid, plug-in hybrid, and battery electric vehicles are shaped by vehicle body size or type. The automobile market is differentiated with vehicle attributes that respond to heterogeneous consumer demands. We hypothesize that each bundle of attributes as it relates to vehicle body size also shapes demand for EVs. Using a large primary dataset, we segment respondents according to their preferred next vehicle body type (economy, intermediate, full-size sedan, luxury, minivan, sport utility, and pickup). Multivariate analysis of variance (MANOVA) results show significant differences in the socioeconomic, demographic, and psychological profile of consumers across the seven vehicle segments. From this, discrete choice models detail how vehicle type plays a significant role in the choicemaking behaviour of potential EV consumers. While factors like age, education, and the importance of fuel economy and reduced or eliminated emissions generally play a consistent role in improving the utility of EVs, our results also reveal significant heterogeneity in choice of powertrain across vehicle segments, with luxury and pickup buyers among the most distinct. The results offer useful information for marketing, policy, and research. [ABSTRACT FROM AUTHOR]

Transit oriented development (TOD), which is generally understood as the provision of higher-density, mixed-use, amenity-rich, and walkable development around rapid transit stations, has been championed as one of the most effective solutions for maximizing the potential return on investment for existing and future rapid transit infrastructure projects. But it is clear that not all implementations of TOD are the same in every station catchment area across a transit network. This heterogeneity in station area contexts presents significant complexity for planners and policymakers interested in understanding existing TOD conditions, an area's TOD potential, and the relevant policy and planning interventions required to achieve planning goals. It also creates complications for researchers interested in associating station contexts with various TOD outcomes. In response, the present paper develops a model-based latent class method for distilling measures of station area TOD inputs into a set of more homogeneous station types. Its application to 372 existing and planned rapid transit stations in the Toronto region reveals a typology of 10 distinct TOD contexts across a number of present and future transit lines. The end result is an empirical tool for policy evaluation and prescription that can be used to benchmark and compare performance of TOD inputs around existing and planned transit stations and offers a foundation for further research into the relationship between TOD inputs and outcomes. Furthermore, the use of latent class analysis improves on the previous literature in this area by offering model results that are easily interpretable and extendable to other applications. [ABSTRACT FROM AUTHOR]

The last three decades have witnessed substantial growth in the literature on excess commuting. Researchers have proposed and applied a number of commuting benchmarks and excess commuting indices that aim to evaluate the commuting efficiency and jobs-housing balance of cities. A comprehensive review and comparative evaluation of the proposed metrics in terms of their ability to capture the intended phenomena, while controlling for the other general characteristics of cities, has yet to be performed. This article attempts to fill this gap by examining four commuting benchmarks ( minimum commute , maximum commute , random commute , and proportionally matched commute ) and five excess commuting indices ( excess commute , commuting potential utilized , commuting economy , normalized commuting economy , and effort ). Our conceptual analysis of the indices is complemented with a comparative empirical analysis of commuting in thirty Canadian cities. We explore relationships between the indices and point out the strengths and limitations of each. The findings suggest that no single index can adequately capture the commuting performance of an urban area, while each index can be employed to address a specific policy question. Used together, the indices can provide a reasonably good understanding of urban form and commuting behavior. [ABSTRACT FROM AUTHOR]

Floating Catchment Area (FCA) methods are a popular choice for modelling accessibility to healthcare services because of their ability to consider both supply and demand. However, FCA methods do not fully consider aspects of travel and choicemaking behaviour as the only behavioural component is the impedance function. FCA approaches also tend to assign population demand to clinics and levels-of-service to population zones in an overlapping manner that has been shown to inflate/deflate supply and demand. While the adjustments proposed in the recent "Balanced FCA" method can rectify this, it apportions population and levels of service in a fractional manner. In response, this research proposes a utility-based measure of healthcare accessibility based on a multinomial logit (MNL) destination choice model that avoids the multiple-counting issue in FCA methods. It also considers additional behavioural aspects that define the appeal of clinics in addition to the travel time required to reach them, including their capacity and level of crowding. Comparisons of the MNL approach with the original and balanced FCA models using data for the City of Hamilton, Canada, suggest that while the accessibility patterns produced by each method are broadly similar, some key differences exist in the calculated accessibilities and their spatial patterns. The MNL model in particular estimates higher accessibilities in suburban and rural areas. After considering their strengths and weaknesses, we argue that both the FCA and MNL approaches offer merit for planning and policy. • Develops a multinomial logit based method for healthcare accessibility. • Compares floating catchment-based with utility-based accessibility. • Balanced floating catchment method corrects for inflation of supply and demand. • Utility-based approach accounts for more aspects of travel behaviour. • Each method has merit for health planning and policy. [ABSTRACT FROM AUTHOR]

Abstract: The near ubiquitous presence of poly- and perfluoroalkyl substances (PFASs) in humans has raised concerns about potential human health effects from these chemicals, some of which are both extremely persistent and bioaccumulative. Because some of these chemicals are highly water soluble, one major pathway for human exposure is the consumption of contaminated drinking water. This study measured concentrations of PFASs in 18 raw drinking water sources and 2 treated wastewater effluents and evaluated 15 full-scale treatment systems for the attenuation of PFASs in water treatment utilities throughout the U.S. A liquid-chromatography tandem mass-spectrometry method was used to enable measurement of a suite of 23 PFASs, including perfluorocarboxylic acids (PFCAs) and perfluorosulfonic acids (PFSAs). Despite the differences in reporting levels, the PFASs that were detected in >70% of the source water samples (n = 39) included PFSAs, perfluorobutane sulfonic acid (74%), perfluorohexane sulfonic acid (79%), and perfluorooctane sulfonic acid (84%), and PFCAs, perfluoropentanoic acid (74%), perfluorohexanoic acid (79%), perfluoroheptanoic acid (74%), and perfluorooctanoic acid (74%). More importantly, water treatment techniques such as ferric or alum coagulation, granular/micro-/ultra- filtration, aeration, oxidation (i.e., permanganate, ultraviolet/hydrogen peroxide), and disinfection (i.e., ozonation, chlorine dioxide, chlorination, and chloramination) were mostly ineffective in removing PFASs. However, anion exchange and granular activated carbon treatment preferably removed longer-chain PFASs and the PFSAs compared to the PFCAs, and reverse osmosis demonstrated significant removal for all the PFASs, including the smallest PFAS, perfluorobutanoic acid. [Copyright &y& Elsevier]

Public bicycle share programs (PBSPs) can play a role in advancing transportation equity if they make bicycling more accessible to disadvantaged populations. In Ontario, Hamilton Bike Share expanded their program in 2018 by adding twelve "equity" stations with the explicit objective of increasing access for under-serviced neighborhoods. In this case study, we investigate differentials in accessibility to stations using a balanced floating catchment area approach and compare accessibility with and without the equity stations. We analyze population interpolated to small cells to better reflect walking to a station and conduct a sensitivity analysis at several walking time thresholds. We then reaggregate the estimated accessibility by income groups for further analysis. Our findings indicate that equity stations increased accessibility for the serviced population at every threshold examined, but the increase was relatively modest especially for population in the bottom 20% of median total household income. • Balanced floating catchment area method applied to measure accessibility to bike share. • Contribution of stations added to increase equity assessed at different thresholds. • Added stations increased accessibility and reduced inequities, albeit only modestly. • Lowest income group has low levels of accessibility, even with "equity" stations. • Location and size of docking stations matters for increasing equity in accessibility. [ABSTRACT FROM AUTHOR]

In this paper we analyze the changes in accessibility to emergency and community food services before and during the COVID-19 pandemic in the City of Hamilton, Ontario. Many of these food services are the last line of support for households facing food insecurity; as such, their relevance cannot be ignored in the midst of the economic upheaval caused by the pandemic. Our analysis is based on the application of balanced floating catchment areas and concentrates on households with lower incomes (

Abstract: Recent laboratory studies with a marine sediment from a tidal mudflat in San Francisco Bay demonstrated that a low dose of activated carbon enhances the sequestration of PCBs and PAHs under well-mixed conditions. Here we compare activated carbon treatment for a freshwater sediment from a rural site, using PCB-contaminated sediment from Lake Hartwell, SC. An activated carbon dose of 2% of the dry sediment mass lowered total aqueous PCB concentrations by more than 95% after 1 month of treatment and more than 98% after 6 months. Aqueous PCB concentrations remained below detection limits following 18 months of sediment–carbon contact in slowly mixed systems. Uptake of PCBs into semipermeable membrane devices was reduced by 78%, 91% and 97% over 1, 6 and 18 months, respectively. These tests show that PCB sequestration with activated carbon improves with contact time and is not diminished by prolonged mixing with sediment. Desorption studies confirmed the sequestration, in which 74% of the total PCB mass could be desorbed from untreated Lake Hartwell sediment within 30 days as compared to only 7% after activated carbon treatment for 6 months. We compare these observations with marine sediment from San Francisco Bay and propose a conceptual model to rationalize how sediment properties relate to the reduction in aqueous PCB concentrations during activated carbon treatment. [Copyright &y& Elsevier]

and perfluorinated alkyl substances (PFASs) are ubiquitously detected all around the world. Herein, for the first time, concentrations of 16 selected legacy and emerging PFASs are reported for sediment and edible fish collected from the Saudi Arabian Red Sea. Mean concentrations varied from 0.57 to 2.6 μg kg−1 dry weight (dw) in sediment, 3.89–7.63 μg kg−1 dw in fish muscle, and 17.9–58.5 μg kg−1 dw in fish liver. Wastewater treatment plant effluents represented the main source of these compounds and contributed to the exposure of PFAS to biota. Perfluorooctane sulfonate (PFOS) was the most abundant compound in sediment and fish tissues analysed, comprising between 42 and 99% of the ∑ 16 PFAS. The short chain perfluorobutanoate (PFBA) was the second most dominant compound in sediment and was detected at a maximum concentration of 0.64 μg kg−1 dw. PFAS levels and patterns differed between tissues of investigated fish species. Across all fish species, ∑ 16 PFAS concentrations in liver were significantly higher than in muscle by a factor ranging from 3 to 7 depending on fish species and size. The PFOS replacements fluorotelomer sulfonate (6:2 FTS) and perfluorobutane sulfonate (PFBS) exhibited a bioaccumulation potential in several fish species and 6:2 FTS, was detected at a maximum concentration of 7.1 ± 3.3 μg kg−1 dw in a doublespotted queenfish (Scomberoides lysan) liver. PFBS was detected at a maximum concentration of 2.65 μg kg−1 dw in strong spine silver-biddy (Gerres longirostris) liver. The calculated dietary intake of PFOS, perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA) and perfluorohexane sulfonic acid (PFHxS) exceeded the safety threshold established by the European Food Safety Authority (EFSA) in 2020 in doublespotted queenfish muscle, indicating a potential health risk to humans consuming this fish in Jeddah, Saudi Arabia. [Display omitted] • PFAS were quantified for the first time in sediment and fish from the Saudi Arabian Red Sea. • WWTP effluents represent the main local source of PFAS. • Despite phase out actions, PFOS was still the most predominant PFAS. • The short chain acid PFBA was also predominant in all sediments analysed. • The fluorotelomer sulfonate 6:2 FTS accumulated in most fish species investigated. [ABSTRACT FROM AUTHOR]

An age-inclusive built environment is essential for promoting an accessible food landscape for the elderly population. However, previous research has focused on least-distance/time travel metrics in a 2D environment, potentially overlooking travelers' physical constraints and underestimating actual walking distances. In contrast, this study employs advanced geocomputational methods that leverage 3D building models, 3D pedestrian networks, and elevation data to appraise the fine-scale spatial accessibility to healthy food in Hong Kong. Guided by the principles of least effort, our findings suggest that 95% of older adults can access healthy food within 913.3m due to Hong Kong's compact and transit-oriented built environment. However, nearly half (47%) of older adults may encounter difficult pedestrian paths even with the least-effort route. Subsequently, the Aggregated Accessibility Index (AAI) is devised to identify communities that require improvement in promoting active living for older people. Site visits were also conducted to validate the AAI and present real-world situations to better articulate the mobility challenges imposed on older adults. Our study underscores the instrumental role of advanced spatial data computation in shaping age-friendly communities that prioritize and enhance spatial accessibility to healthy food, advocating for nuanced urban planning approaches that address the diverse needs of aging populations. • Fine-scale accessibility to healthy food was analyzed by 3D geocomputation methods. • Aggregated Accessibility Index, supplemented with field observation, was designed. • Most older adults are within walking distance of healthy food in the study area. • However, 47% still face difficult paths even with the least-effort routing. • Recommendations for active living and future study are discussed. [ABSTRACT FROM AUTHOR]

A study to determine the accuracy and reliability of telephone communications data obtained via sell-recording diaries was undertaken. The methodology involved comparing data obtained from the diaries to the more objective data provided by the recording capabilities of a PBX (Private branch Exchange). Two questions formed the basis for the analysis. First, what is the level of accuracy of diary data, and, second what biases are inherent in data obtained from self-recorded diaries. The findings indicate that diary data significantly understate the actual frequency of communications. There were also several biases inherent in the diary data. One involved a significant understatement of very short communications (i.e. those lasting less than 90 seconds). The others showed an under-recording of received calls and a likelihood to record internal rather than external cals. The conclusion drawn is that in the absence of objective data (i.e. data obtained from machine recording) diaries can provide usable data as long as one pays attention to the biases inherent in their use. [ABSTRACT FROM AUTHOR]

The crucial role that communication plays in organizations has led to the development of various methodologies to collect communications data. Two of the more common techniques are one-shot questionnaires and self-recording diaries completed at the time of the interaction. Questionnaires are often viewed as unreliable since they are based on the memory and perceptions of the participants. Diaries, on the other hand, are considered to be more reliable since they are completed immediately following an interaction when the event is still fresh in the individual's mind. This paper compares the cross-recorder reliability of these two data collection instruments. A reliability measure which indicates the degree to which an individual concurs as to the occurrence of interactions across all individuals is introduced. The results, based on studies in three organizations involving 49, 61 and 110 participants respectively, indicate that diary data are significantly more reliable than data obtained from questionnaires. [ABSTRACT FROM AUTHOR]

Background: Per- and polyfluoroalkyl substances (PFAS) are a chemical class widely used in industrial and commercial applications because of their unique physical and chemical properties. Between 2013 and 2016 PFAS were detected in public water systems and private wells in El Paso County, Colorado. The contamination was likely due to aqueous film forming foams used at a nearby Air Force base.Objective: To cross-sectionally describe the serum concentrations of PFAS in a highly exposed community, estimate associations with drinking water source, and explore potential demographic and behavioral predictors.Methods: In June 2018, serum PFAS concentrations were quantified and questionnaires administered in 213 non-smoking adult (ages 19-93) participants residing in three affected water districts. Twenty PFAS were quantified and those detected in >50% of participants were analyzed: perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA) and perfluoroheptane sulfonate (PFHpS). Unadjusted associations were estimated between serum PFAS concentrations and several predictors, including water consumption, demographics, personal behaviors and employment. A multiple linear regression model estimated adjusted associations with smoking history.Results: Study participants' median PFHxS serum concentration (14.8 ng/mL) was approximately 12 times as high as the U.S. national average. Median serum concentrations for PFOS, PFOA, PFNA and PFHpS were 9.7 ng/mL, 3.0 ng/mL, 0.4 ng/mL and 0.2 ng/mL, respectively. Determinants of PFHxS serum concentrations were water district of residence, frequency of bottled water consumption, age, race/ethnicity, and smoking history. Determinants of serum concentrations for the other four PFAS evaluated included: water district of residence, bottled water consumption, age, sex, race/ethnicity, smoking history, and firefighter or military employment.Conclusions: Determinants of serum concentrations for multiple PFAS, including PFHxS, included water district of residence and frequency of bottled water consumption. Participants' dominant PFAS exposure route was likely consumption of PFAS-contaminated water, but certain demographic and behavioral characteristics also predicted serum concentrations. [ABSTRACT FROM AUTHOR]

There is a growing need for a broad overview of the state of knowledge on the environmental aspects of Electric Vehicles (EVs), which could help policymakers in the objective of making road transportation more sustainable and environmental friendly. This study provides a comprehensive review of the effects of EVs adoption on air quality, greenhouse gas emissions, and human health. Specifically, we (i) synthesized relevant published literature related to environmental implication of EVs, (ii) quantitatively evaluated the effect of EVs on environment and human health, and (iii) identified research gaps and recommend future research areas for the adoption of EVs and their benefits to society. We assessed in total 4734 studies and selected 123 articles of more detailed review, with 65 articles fulfilling the inclusion criteria. The studies reviewed consistently showed reductions in greenhouse gas emissions and emissions of some criteria pollutants. Particularly on PM and SO 2 , the increases or decreases are very dependent on the context. Overall, the positive benefits of EVs for reducing greenhouse gas emissions and human exposure depends on the following factors: (i) type of EV, (ii) source of energy generation, (iii) driving conditions, (iv) charging patterns, (v) availbailty of charging infrastructure, (vi) govermnat policies, and (vii) climate of a regions. This study provides a comprehansive analysis and review on the benefits of electric mobility. [ABSTRACT FROM AUTHOR]

This paper reports on results developed from a 2015 national survey of Canadian consumers that sought to assess attitudes and preferences towards consumer electric vehicles. A latent class discrete choice model was developed based on stated preferences choices. Four classes emerged with each being oriented to one of the primary vehicle technologies considered. The dominant characteristics of the Internal Combustion Engine (ICE)-oriented class are purchase price sensitivity, EV scepticism and an apparent resistance to change; for the Hybrid Electric Vehicle (HEV)-oriented class it is reluctance to plug-in and an unusual combination of high environmental concern and an acceptance to burn gasoline; for the suburban-oriented Plug-in Hybrid Electric Vehicle (PHEV)-oriented class it is measured optimism about plugging-in combined with an orientation to a replacement vehicle for the next purchase; and for the younger and most urban Battery Electric Vehicle (BEV)-oriented class it is the highest optimism about electric vehicles and a focus on positive aspects such as rapid acceleration and minimized maintenance costs. By orientation of household mindset, approximately 40% are ICE, 30% are PHEV, 20% are HEV and 10% are BEV. These results suggest considerable openness to electric vehicles. Willingness-to-pay for vehicle and charging attributes and incentives were calculated and are highly useful in interpreting the latent classes. The results feature interesting geographical variation which is captured at the level of Canadian metropolitan areas. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fish consumption is a major source of human PFAS exposure. • Lack of harmonization within legislations for PFAS. • Consuming small amounts of fish can lead to exceedance of PFAS safety thresholds. • PFAS exposure via fish consumption pose a challenge for risk communication. Per- and polyfluoroalkyl substances (PFAS) receive global attention due to their adverse effects on human health and the environment. Fish consumption is a major source of human PFAS exposure. The aim of this work was to address the lack of harmonization within legislations (in the EU and the USA) and highlight the level of PFAS in fish exposed to pollution from diffuse sources in the context of current safety thresholds. A non-exhaustive literature review was carried out to obtain PFAS concentrations in wild fish from the Norwegian mainland, Svalbard, the Netherlands, the USA, as well as sea regions (North Sea, English Channel, Atlantic Ocean), and farmed fish on the Dutch market. Median sum wet weight concentrations of PFOA, PFNA, PFHxS, and PFOS ranged between 0.1 µg kg−1 (farmed fish) and 22 µg kg−1 (Netherlands eel). Most concentrations fell below the EU environmental quality standard (EQS biota) for PFOS (9.1 µg kg−1) and would not be defined as polluted in the EU. However, using recent tolerable intake or reference dose values in the EU and the USA revealed that even limited fish consumption would lead to exceedance of these thresholds – possibly posing a challenge for risk communication. [ABSTRACT FROM AUTHOR]

• Dissolved metals and organic contaminants removed with face velocity of 60 cm h−1. • Organics migration increases with face velocity indicating kinetic limitation to removal. • Metal and hydrophobic organic compound removal not affected by increased flow rates. • Intraparticle diffusion-sorption model validated with previously fit parameters. • Kinetic limitations described by intraparticle diffusion-sorption predictive model. Urban stormwater runoff is considered a key component of future water supply portfolios for water-stressed cities. Beneficial use of runoff, such as capture for recharge of drinking water aquifers, relies on improved stormwater treatment. Many dissolved constituents, including metals and trace organic contaminants (TrOCs) such as hydrophilic pesticides and poly- and perfluoroalkyl substances (PFASs), are of concern due to their toxicity, persistence, prevalence in stormwater runoff, and poor removal in conventional stormwater control measures. This study explores the operational flow rate limitations of black carbon (BC)-amended engineered media filters for removal of a wide suite of dissolved metals and TrOCs and provides validation for a previously developed predictive TrOC transport model. Column experiments were conducted with face velocities of 40 and 60 cm h−1 to assess Douglas Fir-based biochar and regenerated activated carbon (RAC) filter performance in light of media-contaminant removal kinetic limitations. This study found that increasing the face velocity in BC-amended filters to 40 and 60 cm h−1, which are representative of field conditions, decreased the removal of total suspended solids, turbidity, dissolved hydrophilic TrOCs, and PFASs when expressed as volume treated relative to previous studies conducted at 20 cm h−1. Dissolved metals and hydrophobic TrOCs removal were not substantially affected by the increased flow rates. A predictive 1-d intraparticle pore diffusion-limited sorption model with sorption and effective tortuosity parameters determined previously from experiments conducted at 20 cm h−1 was validated for these higher flow rates. This work provides insights to the kinetic limitations of contaminant removal within biochar and RAC filters and implications for stormwater filter design and operation. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Onsite wastewater treatment is used by 20% of residences in the United States. The ability of these systems, specifically soil treatment units (STUs), to attenuate trace organic chemicals (TOrCs) is not well understood. TOrCs released by STUs pose a potential risk to downstream groundwater and hydraulically-connected surface water that may be used as a drinking water source. A series of bench-scale experiments were conducted using sand columns to represent STUs and to evaluate the efficacy of TOrC attenuation as a function of hydraulic loading rate (1, 4, 8, 12, and 30 cm/day). Each hydraulic loading rate was examined using triplicate experimental columns. Columns were initially seeded with raw wastewater to establish a microbial community, after which they were fed with synthetic wastewater and spiked with 17 TOrCs, in four equal doses per day, to provide a consistent influent water quality. After an initial start-up phase, effluent from all columns consistently demonstrated >90% reductions in dissolved organic carbon and nearly complete (>85%) oxidation of ammonia to nitrate, comparable to the performance of field STUs. The results of this study suggest STUs are capable of attenuating many TOrCs present in domestic wastewater, but attenuation is compound-specific. A subset of TOrCs exhibited an inverse relationship with hydraulic loading rate and attenuation efficiency. Atenolol, cimetidine, and TCPP were more effectively attenuated over time in each experiment, suggesting that the microbial community evolved to a stage where these TOrCs were more effectively biotransformed. Aerobic conditions as compared to anaerobic conditions resulted in more efficient attenuation of acetaminophen and cimetidine. [Copyright &y& Elsevier]

Abstract: The site-specific daily fluctuations and scale-dependent variability of influent water quality, particularly concentrations of trace organic chemicals (TOrCs), have not yet been well described. In this study, raw wastewater from three distinct sewershed scales was sampled including a centralized wastewater treatment facility in Boulder, Colorado (population ∼125,000) and two decentralized wastewater catchments in Golden, Colorado (clustered system population 400, and septic system population 32). Each site was sampled hourly for 26 h and samples were subsequently analyzed in triplicate for 32 TOrCs using liquid chromatography with tandem mass spectrometry and stable isotope dilution. Detection frequency (DF) of the various TOrCs was positively correlated with sewershed size with the greatest DF of the targeted TOrCs at the Boulder site and with decreasing DF with decreasing sewershed size. Site-specific fluctuations were both scale and compound-specific. The 11 TOrCs detected greater than 75% of the time across all three sites were used to further investigate and quantify variability and to develop a statistical model to investigate the flow-dependence and time-dependence of TOrC variability. Sewershed scale was inversely correlated to variability with coefficients of variation ranging from 0.24 to 0.96, 0.39 to 2.22, and 0.32 to 3.93 for the Boulder, cluster, and septic sites, respectively. A significant linear relationship was observed between concentration and flow and concentration and the concentration at prior time points for most TOrCs at the Boulder site. This suggests less variable influent concentrations result from dispersion and mixing in the conveyance system and a larger number of discrete inputs. A notable exception was the chlorinated flame retardant TCPP, which is likely associated with a high concentration, low-flow industrial input. A significant linear relationship between flow and concentration and sequential time points was not common at the decentralized sites. Scientists and engineers developing decentralized treatment systems must consider a larger range of influent qualities, particularly with respect to TOrCs. [Copyright &y& Elsevier]

Exercise is making a resurgence in many countries, given its benefits for fitness as well as prevention of obesity. This trend has spawned many supplements that purport to aid performance, muscle growth, and recovery. Initially, sports drinks were developed to provide electrolyte and carbohydrate replacement. Subsequently, energy beverages (EBs) containing stimulants and additives have appeared in most gyms and grocery stores and are being used Increasingly by "weekend warriors" and those seeking an edge in an endurance event. Long-term exposure to the various components of EBs may result in significant alterations in the cardiovascular system, and the safety of EBs has not been fully established. For this review, we searched the MEDLINE and EMBASE databases from 1976 through May 2010, using the following keywords: energy beverage, energy drink, power drink, exercise, caffeine, red bull, bitter orange, glucose, ginseng, guarana, and taurine. Evidence regarding the effects of EBs is summarized, and practical recommendations are made to help in answering the patient who asks, "Is It safe for me to drink an energy beverage when I exercise?" [ABSTRACT FROM AUTHOR]

• Route choice is influenced by infrastructure and streetscape. • Bicycling is perceived to be excluded from roads through policy and design. • Regular bicyclists have mixed perceptions of existing infrastructure. • Infrastructure changes should be more aligned with stronger policy changes. • Bicycling uptake may be hindered if it is not more explicitly accommodated. As cities make concerted efforts to become more bicycle-friendly through policy changes and infrastructure, it is important that such efforts ultimately support people who currently bicycle and remove barriers that may prevent more people from bicycling. Travel surveys can reveal the nature and distribution of bicycling trips, but perceptions and behaviours of bicyclists are better understood through qualitative methods. In particular, developing cycling cities are unique settings to examine how the built environment supports bicycling as changes are made to increase bicycling levels. Through semi-structured interviews, this research explores the case of Hamilton, Ontario and the factors that influence route choice from the perspective of regular bicyclists. Major themes were identified using thematic analysis: (i) exclusion from road space; (ii) infrastructure; and (iii) streetscape. Bicyclists highly value infrastructure and seek routes that minimize interactions with cars, while avoiding many arterial roads that prioritize motorists. Routes that appear to be more human-oriented or that have nature are also attractive. Many regular bicyclists report that current bicycle infrastructure does not meet their preferences. Despite building nearly half of the planned infrastructure network, our findings suggest the built environment is not perceived to be oriented to bicycling. This study provides policy and practice recommendations for developing cycling cities in North America as they transition towards established cycling cities. [ABSTRACT FROM AUTHOR]

• Tension tests of glued-in steel rods embedded in mass-ply panels are reported. • A two-step adhesive application process for glued-in steel rods is tested. • Monotonic and cyclic testing show no significant difference in tension capacity. • Elastic stiffness does not change with embedment depth under monotonic loads. • Further testing is required for conclusions on elastic stiffness under cyclic loads. The length of mass timber wall panels is a limiting factor in designing taller buildings. Splice designs are needed to maintain panel transportability while transferring shear and moment forces from higher floors to the foundation under lateral loading. One such splice design utilizes structural adhesive to glue threaded steel rods into the ends of wall panels being connected. This paper reports tests of the tension capacity of glued-in rods embedded in Mass Ply Panels (MPP). Twenty glued-in rods were tested under monotonic and cyclic protocols. Embedment depths ranged between 304.8 mm (12 in.) and 812.8 mm (32 in.). Load and displacement were measured during tests to report values per ISO 6891 and an international code council acceptance criteria document. Elastic stiffness, peak capacity, design capacity, and a predictive capacity equation were determined. Results showed a similar stiffness for all embedment depths and a negligible difference between peak capacities from monotonic and cyclic testing. While the data reported is only directly applicable for analysis of the specific MPP and epoxy combination used in the test program, the methodology herein can be utilized for future testing of timber-adhesive glued-in rods. [ABSTRACT FROM AUTHOR]

Abstract Liquid chromatography high-resolution mass spectrometry (LC-HRMS) shows great potential for expanding our understanding of relevant unknown chemical components present within complex environmental mixtures. This study identified potentially endocrine active components within Minnesota lakewater by prioritizing LC-HRMS features uniquely present at sunfish spawning habitats where male fish showed signs of estrogen agonism. Porewater samples from four locations within the same lake were analyzed using liquid chromatography quadrupole time of flight mass spectrometry (LC-QToF/MS) with positive (ESI+) and negative (ESI−) electrospray ionization. Plasma vitellogenin concentrations of captured male sunfish was used to designate sites as either endocrine active (ACT; 2 sites) or reference (REF; 2 sites). Assuming unique chemical presence at active sites contributed to endocrine activity, features at significantly higher intensities (p -value < 0.05, t-value > t-critical, log-fold change > 0.1; equal variance t -test of log2 transformed data) in ACT sites were then compiled into a suspect search list for feature identification. Adducts and isotopes of prioritized features were deprioritized using pattern recognizing algorithms using mass, retention time, and intensity. Feature identities were reported according to established confidence metrics using spectral libraries and elemental composition algorithms. This LC-HRMS approach identified a number of features omitted by targeted analysis with higher relative abundances in ACT sites, including plant essential oils, fatty acids, and mycotoxins. Multivariate analysis determined whether features were either present at both sites (AB) or unique to individual ACT sites (A or B). Detection frequency across datasets indicated bias in feature prioritization influenced by the chosen sampling method and sample acquisition mode. The majority of features prioritized by this workflow remain tentatively identified or unidentified masses of interest, reflective of current limitations in shared spectral libraries for soft ionization analyses. Strategies similar to this workflow have the potential to reduce bias in database-driven toxicological prioritization frameworks. Graphical abstract Unlabelled Image Highlights • Suite of LC-HRMS features at higher abundance in endocrine active sites • Confidently identified features omitted or listed as inactive by EDSP21 Dashboard • Feature prioritization dependent on grab versus composite field sampling [ABSTRACT FROM AUTHOR]