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The toxicokinetics of triphenyl phosphate (TPHP) in vivo including the uptake, deposition, and biotransformation into the metabolite diphenyl phosphate (DPHP) is presently reported in embryonated eggs and chicks of Japanese quail. Quail were dosed with TPHP at 3 concentrations by air cell egg injection on embryonic day 0, followed by daily oral dosing after chicks hatched (5 d). Vehicle‐only exposed controls were also used. In dosed eggs, only 33% of the TPHP remained 2 d after injection (no hepatic development); after 10 d (post‐hepatogenesis), only 2% remained. The estimated TPHP half‐lives in the eggs ranged from 1.1 to 1.8 d for the 3 dosed groups. In all exposed eggs and chicks, DPHP significantly increased with dose (0.001 < p < 0.044). It appears that DPHP is an important metabolite in quail, making up 41 to 74% of all metabolites formed in embryonated eggs. In chicks, at medium and high doses, DPHP concentrations significantly exceeded those of TPHP (p ≤ 0.007), making up 67 and 76% of the total burden, respectively. Our findings suggest that rapid TPHP metabolism occurred in chicks and embryonated quail eggs but that this may vary with the age of the embryonated egg and the stage of embryo development, which should be considered when evaluating concentrations of TPHP and DPHP measured in eggs of wild birds. Environ Toxicol Chem 2020;39:565–573. © 2019 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry © 2019 SETAC [ABSTRACT FROM AUTHOR]

BACKGROUND: Falls are among the leading causes of occupational injuries for workers exposed to outdoor winter conditions such as Personal Support Workers (PSWs). Slip resistant footwear is known to reduce the risk of falls, however, it is difficult to predict how well a particular boot will perform prior to purchasing them. Our recently developed Maximum Achievable Angle (MAA) test can be used to rate footwear objectively to address this gap. OBJECTIVE: To rate the slip resistance of a selection of winter footwear that meets the needs and preferences of PSWs. METHODS: We selected 40 representative types of footwear based on survey results from 677 PSWs and applied our MAA test to rate slip resistance. RESULTS: Comfort and slip resistance were rated the most important features for selecting winter footwear. Of the 40 types of footwear tested, six were found to have a good slip resistance on ice. CONCLUSION: The vast majority of winter footwear that meet the needs and preferences of PSWs, perform poorly on ice. Therefore, PSWs should consult our website (ratemytreads.com) for selecting appropriate footwear that will keep them safe in the winter. [ABSTRACT FROM AUTHOR]

Concentrations of Mirex, Dechlorane (Dec) Plus (DP), Dec 602, Dec 603, and Dec 604 were significantly higher in peregrine falcon (Falco peregrinus) eggs from Canada than Spain, with the former having the only measurable concentrations of the dechlorinated DP products, decacliloropentacydooctadecadiene (aCl10DP) and undecachloropentacyclooctadecadiene (aCI11DP). Large variations also occurred in the in ovo concentrations of the DP monoadduct, DPMA. This is the first study to report die accumulation and metabolism of DP by peregrines, both DP and dechloranes in European biota, as well as dechloranes in a terrestrial organism and one at the top of the food web. The geographical differences in the measured in ovo concentrations reflect local exposure of the adult peregrines on their breeding ground, likely differences in diet of the adults, the production of DP on the Niagara River, and the greater use of Mirex and dechloranes as flame retardants in North America than Europe. [ABSTRACT FROM AUTHOR]

Concentrations and spatial patterns of persistent organic (chlorinated) pollutants (POPs), polybrominated diphenyl ether (PBDE), hexabromocyclododecane (HBCD), other flame retardants, and hydroxylated (OH) PBDE and PCB compounds were determined in nestling peregrine falcons across the Canadian Great Lakes Basin. The highest geometric mean plasma POP concentrations (ng/g ww) were sum (Σ)PCBs (35.16), ΣPBDEs (15.38), and ΣOH-PCB (8.77) with the lowest mean levels in nestlings from urban versus remote nests. PBDE congeners derived from PentaBDE and OctaBDE technical mixtures had the highest concentrations, sometimes exceeding 100 ng/g wet weight (ww); BDE-99, -153, -47, -100, and -183 comprised 92.7% of the Σ14PBDE levels. BDE-209 proportions were minimal (<1%). North Shore (Lake Superior) nestlings had the highest Σ14PBDE concentrations, with BDE-99, -153, and -47 dominant. Urban nestlings had higher BDE-99:BDE-153 ratios, higher BDE-183 proportions, and the only detectable HBCD concentrations, suggesting greater and more localized exposure to HBCD and PBDEs derived from OctaBDEs. Spatial patterns reflected differences in diet, local contaminant sources, and/or atmospheric deposition. Metabolism of PCBs and PBDEs likely occurred in these nestlings: OH-PCB metabolites were detected, and 4-OH-CB187 was the most abundant of these metabolites. Low ppb levels of putative OH-PBDE metabolites, dominated by 6'-OH-BDE47, were also detected in the peregrine nestlings. [ABSTRACT FROM AUTHOR]

Trip-related falls are one of the major causes of injury among seniors in Canada and can be attributable to an inadequate Minimum Toe Clearance (MTC). Currently, motion capture systems are the gold standard for measuring MTC; however, they are expensive and have a restricted operating area. In this paper, a novel wearable system is proposed that can estimate different foot clearance parameters accurately using only two Time-of-Flight (ToF) sensors located at the toe and heel of the shoe. A small-scale preliminary study was conducted to investigate the feasibility of foot clearance estimation using the proposed wearable system. We recruited ten young, healthy females to walk at three self-selected speeds (normal, slow, and fast) while wearing the system. Our data analysis showed an average correlation coefficient of 0.94, 0.94, 0.92 for the normal, slow, and fast speed, respectively, when comparing the ToF signals with motion capture. The ANOVA analysis confirmed these results further by revealing no statistically significant differences between the ToF signals and motion capture data for most of the gait parameters after applying the newly proposed foot angle and offset compensation. In addition, the proposed system can measure the MTC with an average Mean Error (ME) of −0.08 ± 3.69 mm, −0.12 ± 4.25 mm, and −0.10 ± 6.57 mm for normal, slow, and fast walking speeds, respectively. The proposed affordable wearable system has the potential to perform real-time MTC estimation and contribute to future work focused on minimizing tripping risks. [ABSTRACT FROM AUTHOR]

We examined the concentrations and spatial patterns of congeners of PBDEs, PCBs, and organochlorine pesticides in snapping turtle (Chelydra serpentina) eggs from Areas of Concern (AOCs) on the Canadian shores of Lake Ontario, St. Lawrence River, and connecting channels. Eggs from Lyons Creek (Niagara River AOC) reflected a local PCB source over a range of 7.5 km (3.2 - 10.8) from the Welland Canal. PCB contamination in eggs declined with increasing distance from the Welland Canal, whereas the relative contribution of congeners associated with Aroclor 1248/1254 increased with ΣPCB concentrations. Compared to turtle eggs from other sites in Lake Erie and Lake Ontario, eggs from Lyons Creek and Snye Marsh had PCB congener patterns that reflected a strong contribution from Aroclor 1254. PCBs in the eggs were associated with industrial sources and reflected the composition of different Aroclor technical mixtures. Organochlorine pesticides in eggs tended to be highest at Hamilton Harbour and Bay of Quinte AOCs, and were dominated by DDE, Σchlordane, and mirex. In contrast, PBDE congener patterns in turtle eggs resembled PentaBDE technical formulations regardless of absolute concentrations or location, and were largely associated with urban environments. [ABSTRACT FROM AUTHOR]

Slip-induced falls are among the most common causes of major occupational injuries and economic loss in Canada. Identifying the risk factors associated with slip events is key to developing preventive solutions to reduce falls. One factor is the slip-resistance quality of footwear, which is fundamental to reducing the number of falls. Measuring footwear slip resistance with the recently developed Maximum Achievable Angle (MAA) test requires a trained researcher to identify slip events in a simulated winter environment. The human capacity for information processing is limited and human error is natural, especially in a cold environment. Therefore, to remove conflicts associated with human errors, in this paper a deep three-dimensional convolutional neural network is proposed to detect the slips in real-time. The model has been trained by a new dataset that includes data from 18 different participants with various clothing, footwear, walking directions, inclined angles, and surface types. The model was evaluated on three types of slips: Maxi-slip, midi-slip, and mini-slip. This classification is based on the slip perception and recovery of the participants. The model was evaluated based on both 5-fold and Leave-One-Subject-Out (LOSO) cross validation. The best accuracy of 97% was achieved when identifying the maxi-slips. The minimum accuracy of 77% was achieved when classifying the no-slip and mini-slip trials. The overall slip detection accuracy was 86% with sensitivity and specificity of 81% and 91%, respectively. The overall accuracy dropped by about 2% in LOSO cross validation. The proposed slip detection algorithm is not only beneficial for footwear manufactures to improve their footwear slip resistance quality, but it also has other potential applications, such as improving the slip resistance properties of flooring in healthcare facilities, commercial kitchens, and oil drilling platforms. [ABSTRACT FROM AUTHOR]

This article presents information about the studies, which deal with downtown retailing in two cities of Canada and the United States. These studies were originally presented at the annual CIRM conference at Manchester in September 2004. One of the cities discussed in the article is Toronto of Canada and another is a mid-west American city. One such study discusses the downtown planning theme with a study of the evolution of retailing in the historic center of Utrecht between 1979 and 2003. In this study by using entropy statistics, the researchers show that the "retail mix" of uses has changed over time with the center maintaining its viability because of the emergence of formats which appeal to the recreational shopper.

Abstract: Comparisons of brominated flame retardants (BFRs) in the eggs of peregrine falcons (Falco peregrinus) recently collected (2003–2007), are made between Canada (N=12) and Spain (N=13). Overall, concentrations of sum (Σ) polybrominated diphenyl ethers (PBDEs; 16 di-deca-BDE congeners) exceeded Σhexabromocyclododecane (HBCD) and were an order of magnitude higher than 2,2′4,4′,5,5′-hexabromobiphenyl (BB-153)>hexachlorocyclopentenyl-dibromocyclooctane (HCBDCO)>1,2-bis(2,4,6-tribromophenoxy)ethane (BTBPE)>decabromodiphenylethane (DBDPE)>octabromotrimethylphenyllindane (OBIND)>hexabromobenzene (HBB)>bis(2-ethyl-1hexyl)tetrabromophthalate (BEHTBP). This is the first report of detectable HBCDCO and BEHTBP concentrations in biota, and the highest in ovo concentration of ∑HBCD (14,617ng/glw; Montreal, Canada) to date. There were significantly greater egg concentrations of BB-153, ΣHBCD, and ΣPBDE including BDE-153, -99, -100 and -183, in Canadian than Spanish peregrines with a terrestrial diet. HBB, BTBPE, and OBIND were detected in eggs from both countries, but only Canadian peregrine eggs had detectable levels of HCDBCO (25%) and DBDPE (N=1). The in ovo PBDE congener profile was dominated by BDE-153>BDE-99>BDE-47>BDE-183>BDE-100>BDE-209, with the isomeric HBCD pattern being α-HBCD>γ-HBCD (β-HBCD undetected). The Canadian peregrine eggs had lower enantiomeric HBCD values consistent with their higher fractions of (−) α-HBCD, suggesting selective enantiomeric enrichment or that the (+) α-isomer is more readily metabolized and so deposited in the egg through maternal transfer. Continental differences in egg burdens of peregrines are discussed relative to BFR usage patterns and exposure of peregrines on their breeding grounds. [Copyright &y& Elsevier]

Perfluoroalkyl substances (PFAS) are a large, diverse group of chemicals and several perfluoroalkyl acids (PFAAs) are known environmental contaminants. Wildlife exposure to PFAAs and precursors has been shown, but less is known regarding replacements such as shorter-chain PFAS. In the present study, exposure to a suite of PFAAs and associations with dietary, biological and ecological factors were investigated in populations of a sentinel apex species – the peregrine falcon (Falco peregrinus). Nestling blood (n = 57) and sibling eggs (n = 9) were sampled in 2016 and 2018 from nests in rural and urban regions across the Laurentian Great Lakes Basin, Canada. PFSAs (perfluorinated sulfonic acids) including PFHxS, PFOS, and PFDS were detected in most egg and plasma samples, whereas 11 PFCAs (perfluorinated carboxylic acids; C 5 –C 14 , C 16) compared to eight PFCAs (C 8 –C 14 , C 16) were detected in most eggs and plasma, respectively. Shorter-chain C 8 –C 10 PFCAs were more dominant in plasma and longer-chain C 12 –C 14 PFCAs in eggs, but profiles were similar for PFOS, PFDS, PFUdA and PFHxDA. The exposure to PFAAs in peregrine falcons is likely mediated by dietary factors such as foraging location (δ 13C and δ 34S) and trophic position (δ 15N) given the associations observed in eggs and nestling plasma, respectively. Moreover, significant relationships were observed for circulating ΣPFCAs and region (rural/urban), and nestling body condition after adjusting for sampling year and dietary tracers, suggesting that compared to rural nestlings, urban nestlings may be more exposed to ΣPFCAs and prone to their potential physiological impacts. Our findings highlight the importance of integrating dietary, biological and ecological factors when studying PFAS exposure in birds. • PFSAs, PFCAs and FASAs measured in peregrine falcons from the Laurentian Great Lakes. • Most PFAA levels, ratios differed between eggs and plasma of sibling nestlings. • ΣPFSAs and ΣPFCAs in nestling plasma were associated with δ 15N and δ 34S or δ 13C. • Evidence suggests urban diet contributes to higher plasma PFCAs for peregrines. • Nestlings' body condition was significantly and negatively associated with ΣPFCAs. [ABSTRACT FROM AUTHOR]