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Recent fluid inclusion analysis indicates that uranium‐bearing brines were present in both the sandstone and the basement at the time of ore genesis in the Athabasca Basin, Canada. However, the question of how the location of uranium‐rich brines controls the formation of unconformity‐related uranium deposits remains unresolved. In this study, four reactive flow modeling scenarios are designed to address this outstanding issue. Our numerical results confirm that the basement‐hosting uranium‐rich brines are capable of forming high‐grade concentrated uranium deposits in the footwall region of the fault zone below the unconformity interface. In contrast, the sandstone‐hosting uranium‐rich brines lead to the formation of low‐grade sheet‐like uranium mineral precipitates above the sandstone layer rather than in the basement. Therefore, this study reveals that unconformity‐related uranium deposits tend to be formed when the basement unit serves as the main uranium source. Taking the sandstone layer as the main uranium source, no unconformity‐related uranium deposits can be formed since the resultant uranium precipitation has no spatial relation with the unconformity interface. Key Points: First numerical investigation into the role of the location of uranium‐rich brines in controlling unconformity‐related uranium depositionBasement‐hosting uranium‐rich brines favor the formation of unconformity‐related uranium depositsSandstone‐hosting uranium‐rich brines do not support the formation of unconformity‐related uranium deposits [ABSTRACT FROM AUTHOR]

Several lacustrine carbonate beds, each a metre‐thick interval of densely packed Mn‐rich sideritic micro‐spherulites or Mn‐rich ferroan calcite micro‐spherulites, are recorded for the first time within strata of the Lower Cretaceous McMurray Formation of the northern Athabasca Oil Sands deposit, western Canada. A lower McMurray lacustrine carbonate deposit is characterised by a metre‐thick bed fabric of Mn‐rich siderite micro‐spherulites. The middle and upper interval McMurray beds developed fabrics of Mn2+‐rich ferroan calcite micro‐spherulites. These carbonate beds represent saline lacustrine depositional environments that resulted from the lake bottom sediments ingressed from below by Mn2+‐Fe2+‐rich carbonate‐saturated brines. These up‐section migrations of Devonian formation water were sourced from dissolution trends developed in limestone and halite‐anhydrite beds of the underlying Devonian Prairie Evaporite during Cordilleran deformation of the Alberta Basin foreland. These brines ascended to the overlying McMurray Formation sediments along dissolution‐collapse structures such as breccia pipes, sinkholes and margins of differentially subsided Upper Devonian fault blocks. The up‐section migration of a sulphate‐saturated Fe2+ and Mn2+‐rich brine resulted in the ingress of a lower McMurray lacustrine bottom sediment at a site associated with the development of a peat mire terrain. Microbial redox of the lake bottom sediment resulted in a carbonate bed of micro‐spherulitic fabrics of Mn‐rich siderite interwoven with pyrite laminae. Subsequent salt dissolution events and up‐section migrations of Devonian brine during deposition of the middle and upper McMurray intervals resulted in similar carbonate‐saturated but sulphate‐poor chemistry. These saline flows also ingressed lacustrine bottom sediments below, and resulted in limestone beds of densely packed spherulitic fabrics of Mn‐ferroan calcite, not siderite. These deposits provide insight into largely unknown dispositions of voluminous brine resulting from salt dissolution trends below the Athabasca Oil Sands and further our understanding of controversial McMurray depositional processes. [ABSTRACT FROM AUTHOR]

• N 2 - and scCO 2 -brine core-flooding experiments were undertaken to examine the elevated temperature stress-dependent relative permeability. • The increase in temperature (20–70⁰C) led to a 24 % rise in irreducible brine saturation, and the end-point gas mobility nearly doubled. • Substituting N 2 with scCO 2 resulted in a leftward shift of brine and gas relative permeability curves. This study delves into the intrinsic and multiphase flow properties, specifically steady-state drainage relative permeability, of a subsurface Deadwood sandstone from the Aquistore CO 2 storage site in Canada. Consecutive core-flooding experiments were conducted utilizing N 2 - and scCO 2 -brine pairs across a broad range of temperatures (20–70 °C) and isotropic effective stress (0–30 MPa). Moreover, we monitored crack initiation and propagation of the sandstone during uniaxial loading at an elevated temperature using an integrated approach that combines microCT scanning with an in-situ heating/loading test. Our findings reveal a 54 % decrease and a 3 % increase in the absolute permeability of the sandstone through isothermal compaction followed by thermal expansion processes, respectively. Elevating the temperature from 20 °C to 70 °C results in a systematic 24 % increase in irreducible brine saturation and nearly doubles the end-point N 2 mobility, indicating an increased tendency of the rock surface towards the brine phase with temperature. Substituting N 2 with scCO 2 demonstrates a leftward shift in relative permeability and a decrease in irreducible brine saturation (from 0.36 to 0.31), consistent with low interfacial tension and the de-wetting effect during cyclic scCO 2 -brine injections. Micro-CT image analysis reveals micro-crack initiation at 10 MPa stress and 70 °C temperature, suggesting that a mixed impact of induced cracks, dynamic wettability, and thermo-mechanical deformation is responsible for the substantial increase in well injectivity over time in Aquistore. This novel experimental program provides indispensable insight into thermo-poromechanical and wettability controls on multiphase flow at the Aquistore injection site in Canada, with potential applicability to similar scenarios globally. [ABSTRACT FROM AUTHOR]

We performed experiments to determine the solubility of Au and Pd in magmatic aqueous fluids as a function of oxygen fugacity (ƒO 2), temperature (T), pH and total chloride concentration (Cl total). Experiments were conducted at 800–1000 °C and 200 MPa in an externally-heated rapid-quench Molybdenum-Hafnium Carbide (MHC) cold-seal pressure vessel assembly. We employed a synthetic fluid inclusion (SFI) technique to entrap equilibrated, hydrothermal fluids in response to in situ fracturing of quartz cylinders at experimental run conditions. The solubility of Au and Pd both have positive relationships with ƒO 2 , temperature, acidity and chlorinity. Concentrated aqueous brines containing 63 wt.% NaCl can dissolve wt.% levels of Au (∼1.2 wt.%) and Pd (∼1.7 wt.%) at metal saturation in relatively oxidized conditions, 1.44 log units above the Ni-NiO oxygen buffer (NNO+1.44), and mildly acidic pH at 900 °C and 200 MPa. Thermodynamic modeling of experimental results suggests that Au is mainly transported as AuCl (aq) at high pH and low Cl total conditions, whereas HAuCl 2(aq) and potentially AuCl 2(aq) − predominates at low pH and high Cl total conditions. Results from thermodynamic modeling also suggest Pd is mobilized in significant contributions by both PdCl 2(aq) and PdCl 3(aq) − with the latter gaining predominance in response to increasing Cl total. Calculated fluid/melt partition coefficients for Au and Pd in low-density, magmatic vapors at 1000 °C and 200 MPa suggest that Pd may experience fractionation from Au in porphyry Au-Cu (±Pd, Pt) systems due to the restricted compatibility of Pd in the fluid phase (requiring strongly acidic and substantially high ƒO 2 conditions). Moreover, high-density, concentrated aqueous brines facilitate the compatibility of Pd in the fluid phase which may be important with respect to the formation of platinum-group element (PGE)-enriched horizons in layered mafic intrusions (e.g., J-M Reef, Stillwater Complex, U.S.A.). The potential for magmatic, near-neutral pH, high-salinity brines to dissolve significant amounts of Pd as Pd(II)-chloride complexes (∼400 to ∼900 µg/g) well below the NNO buffer suggests that such fluids may be responsible for late-stage hydrothermal remobilization of Pd within mafic-ultramafic igneous environments (e.g., Cu-Ni-PGE footwall deposits and low-sulfide PGE deposits in the Sudbury Igneous Complex, Canada). [ABSTRACT FROM AUTHOR]

Background Accurate estimates of the usual intake of nutrients are important for monitoring nutritional adequacy and diet quality of populations. In Canada, comprehensive, nationally representative nutrient estimates have not been available since the Canadian Community Health Survey (CCHS)–Nutrition 2004 survey. Objective The objective of this research was to assess nutrient intakes, distributions, and adequacy of the intakes of Canadian adults. Methods Participants' first 24-h dietary recall, and the second-day recall from a subset of participants from the recently released CCHS 2015 Public Use Microdata File (PUMF) were used to estimate usual intakes of macronutrients, vitamins, and minerals in adults [≥19 y, excluding lactating females and those with invalid energy intake (EI)]. Usual intakes by DRI age-sex groups were estimated using the National Cancer Institute method, adjusted for age, sex, misreporting status, weekend/weekday, and sequence of recall analyzed (first/second) with outliers removed (final sample, n  = 11,992). Usual intakes from food were assessed for prevalence of inadequacy in relation to DRI recommendations. Results Canadian macronutrient intakes were within the recommended acceptable macronutrient distribution ranges. EI was 2154 kcal/d for males (19+) and 1626 kcal/d for females (19+). A high prevalence of inadequate intakes was seen for vitamin A (>47%), vitamin D (>94%), vitamin C (>29% for nonsmokers and >59% for smokers), magnesium (>45%), and calcium (>44%), whereas <25% and <40% of adults (19+) had intakes above the adequate intake for fiber and potassium, respectively. Canadians continue to consume sodium in excess of recommendations (74.8% of males and 47.6% of females). Conclusions A significant number of Canadian adults may not be meeting recommendations for several essential nutrients, contributing to nutrient inadequacies. These results highlight the nutrients of concern by specific age-sex groups that may be important for public health interventions aimed at improving diet quality and nutrient adequacy for Canadian adults. [ABSTRACT FROM AUTHOR]

Introduction: This study examined the prevalence of pre-hypertension (PHT) and hypertension (HT) in urban youth, and assessed the effects of sodium intake and obesity on blood pressure (BP) by ethnicity. Methods: A convenience sample of 557 multiethnic youth, aged 11–23 years, was recruited from 12 schools and institutions in Edmonton, Alberta, Canada. Participants were divided by self-identified ethnicity into four groups (Indigenous, African and Middle Eastern (AME), Asian, and European). Results: Between October 2013 and March 2014, one-on-one interviews were conducted to collect data on demographics, physical activity, diet, and Body Mass Index (BMI). BP was obtained at two different times during the interview and measured a third time in cases of high variability. The standard deviation scores (SDS) of systolic BP (SBP) and diastolic BP (DBP) were used to estimate associations with sodium intake (per 1000 mg/day). Overall, 18.2% and 5.4% of the participants had PHT and HT, respectively. Indigenous and AME participants showed the highest rates of PHT (23.1%). Indigenous and European participants showed higher rates of HT (8.3% and 5.3%, respectively) than other ethnic groups (AME = 4.4%, Asian = 3.9%). There was a positive association between 1000 mg/day increase in sodium intake and SDS of SBP by 0.041 (95% CI 0.007–0.083; p = 0.04) among pre-hypertensive participants. Over 85% of participants exceeded the recommended dietary sodium intake. Mean BMI and dietary sodium intake were higher among pre-hypertensive participants (4219 mg/day) than normotensive (3475 mg/day). Conclusions: The prevalence of HT varied by ethnicity. High dietary sodium intake was of concern. There is a need for culturally-tailored, population-based interventions to reduce sodium intake. [ABSTRACT FROM AUTHOR]

Distributions of calcareous calthemite deposits have been widely documented, but depositional processes and the architecture of their internal fabrics are not well understood. These concrete degradation products from a case study area in western Canada have external morphologies comparable to calcite speleothems formed in natural limestone caves, but the internal microstructural architecture and mineralogy are markedly different. The mineralogy consists of mostly calcite with secondary halite and minor percentages of trona and portlandite. A novel morphogenetic model explains depositional processes resulting in calcareous crusts that follow fractures of an overlying concrete surface, and how sufficient structural integrity provided by the internal architecture supports attachment areas of tubular soda straws. Interiors of these multi-cm crusts consist of curvilinear calcite laminae arrayed as sub-parallel walls, compartmentalizing water–gas interfaces along variously interconnected conduits and basin-form chambers. Overall porosities of 40–60% or more are prevalent, in contrast to < 1% associated with externally similar drapery-form crusts deposited within natural limestone caves. Several calcite fabrics new to calthemite deposits are described, including dendritic shrubs that coalesce into concentric growth rings along central canals of soda straws. [ABSTRACT FROM AUTHOR]

Dietary sodium is required in very small amounts to support circulating blood volume and blood pressure (BP). Available nutritional surveillance data suggest that most Canadian children consume sodium in excess of their dietary requirements. Approximately 80% of the sodium Canadians consume comes from processed and packaged foods. High sodium intakes in children may be an indicator of poor diet quality. Results from systematic reviews and meta-analyses have demonstrated that decreasing dietary sodium in children leads to small but clinically insignificant decreases in BP. However, population-level strategies to reduce sodium consumption, such as food product reformulation, modifying food procurement processes, and federal healthy eating policies, are important public health initiatives that can produce meaningful reductions in sodium consumption and help to prevent chronic disease in adulthood. [ABSTRACT FROM AUTHOR]

Processed foods have been part of the human diet from the very earliest times. Recently, processed foods have come under scrutiny, particularly the category ultraprocessed foods as defined in the NOVA classification of foods. The basic tenet behind this renewed concern about ultraprocessed foods is that it is processing per se, which matters in diet and health, not nutrients or foods. Notwithstanding this, the literature on ultraprocessed foods is almost entirely focused around nutrients and obesity. However, not all studies have found positive links between obesity and ultraprocessed food intake. The category, ultraprocessed foods, is large, accounting for approximately 60% of energy intake and 90% of added sugar intake. The advocates of the NOVA system advise that the intakes of these foods should be avoided, but the scientific basis for this advice is very weak. Thus, a reduction in ultraprocessed foods has been advocated covering 16 foods to reduce US intakes of added sugar. However, when US food consumption data are examined on a food-by-food basis, only 6 of these 16 foods are associated with high added sugar intakes. Data from the United States, United Kingdom, Canada, and Brazil fail to show a relationship between percent energy from ultraprocessed foods and the intakes of fats, saturated fatty acids, or sodium. There is a positive association between ultraprocessed food intake and the intake of added sugar. A negative correlation with dietary fiber is found. This is not surprising, because almost all added sugar is found in the category, ultraprocessed foods, while the majority of dietary fiber is excluded. When compared with the scientific literature, there is little scientific basis for limiting the use of infant foods, fat spreads, or commercially prepared breads in the present diet. [ABSTRACT FROM AUTHOR]

Background Sodium-reduced packaged food products are increasingly available to consumers; however, it is not clear whether they are suitable for inclusion in a potassium-reduced diet. For individuals with impaired renal potassium excretion caused by chronic kidney disease and for those taking certain medications that interfere with the rennin-angiotensin aldosterone axis, the need to limit dietary potassium is important in view of the risk for development of hyperkalemia and fatal cardiac arrhythmias. Objective The primary objective of this study was to determine the impact of the reduction of sodium in packaged meat and poultry products (MPPs) on the content of potassium and phosphorus from food additives. Design This was a cross-sectional study comparing chemically analyzed MPPs (n=38, n=19 original, n=19 sodium-reduced), selected from the top three grocery chains in Canada, based on market share sales. All MPPs with a package label containing a reduced sodium content claim together with their non-sodium-reduced packaged MPP counterparts were selected for analysis. The protein, sodium, phosphorus, and potassium contents of sodium-reduced MPPs and the non-sodium-reduced (original) MPP counterparts were chemically analyzed according to the Association of Analytical Communities official methods 992.15 and 984.27 and compared by using a paired t test. The frequency of phosphorus and potassium additives appearing on the product labels' ingredient lists were compared between groups by using McNemar’s test. Results Sodium-reduced MPPs (n=19) contained 44% more potassium (mg/100 g) than their non-sodium-reduced counterparts (n=19) (mean difference [95% CI): 184 [90-279]; P =0.001). The potassium content of sodium-reduced MPPs varied widely and ranged from 210 to 1,500 mg/100 g. Potassium-containing additives were found on the ingredient list in 63% of the sodium-reduced products and 26% of the non–sodium-reduced products ( P =0.02). Sodium-reduced MPPs contained 38% less sodium (mg/100 g) than their non–sodium-reduced counterparts (mean difference [95% CI]: 486 [334-638]; P <0.001). The amounts of phosphorus and protein, as well as the frequency of phosphorus additives appearing on the product label ingredient list, did not significantly differ between the two groups. Conclusions Potassium additives are frequently added to sodium-reduced MPPs in amounts that significantly contribute to the potassium load for patients with impaired renal handling of potassium caused by chronic kidney disease and certain medications. Patients requiring potassium restriction should be counseled to be cautious regarding the potassium content of sodium-reduced MPPs and encouraged to make food choices accordingly. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate differences in calories, nutrient content, overall healthfulness, and use of sweetener ingredients between products with and without sugar claims. Consumers assume products with sugar claims are healthier and lower in calories. It is therefore important claims be found on comparatively healthier items. This study is a cross-sectional analysis of the University of Toronto's 2013 Food Label Database. Subcategories where at least 5% of products (and n ≥ 5) carried a sugar claim were included ( n = 3048). Differences in median calorie content, nutrient content, and overall healthfulness, using the Food Standards Australia/New Zealand Nutrient Profiling Scoring criterion, between products with and without sugar claims, were determined. Proportion of products with and without claims that had excess free sugar levels (≥10% of calories from free sugar) and that contained sweeteners was also determined. Almost half (48%) of products with sugar claims contained excess free sugar, and a greater proportion contained sweeteners than products without such claims (30% vs 5%, χ2 = 338.6, p < 0.0001). Overall, products with sugar claims were 'healthier' and had lower median calorie, free sugar, total sugar, and sodium contents than products without claims. At the subcategory level, reductions in free sugar contents were not always met with similar reductions in calorie contents. This study highlights concerns with regards to the nutritional composition of products bearing sugar claims. Findings can support educational messaging to assist consumer interpretation of sugar claims and can inform changes in nutrition policies, for example, permitting sugar claims only on products with calorie reductions and without excess free sugar. [ABSTRACT FROM AUTHOR]

Background: Approximately 2 in 3 US adults have prehypertension or hypertension that increases their risk of cardiovascular disease. Reducing sodium intake can decrease blood pressure and prevent hypertension. Approximately 9 in 10 Americans consume excess sodium (≥2300 mg/d). Voluntary sodium standards for commercially processed and prepared foods were established in North America, but their impact on sodium intake is unclear. Objective: We modelled the potential impact on US sodium intake of applying voluntary sodium standards for foods. Design: We used NHANES 2007-2010 data for 17,933 participants aged ≥1 y to model predicted US daily mean sodium intake and the prevalence of excess sodium intake with the use of the standards of the New York City's National Salt Reduction Initiative (NSRI) and Health Canada for commercially processed and prepared foods. The Food and Nutrient Database for Dietary Studies food codes corresponding to foods reported by NHANES participants were matched to NSRI and Health Canada food categories, and the published sales-weighted mean percent reductions were applied. Results: The US population aged ≥1 y could have reduced their usual daily mean sodium intake of 3417 mg by 698 mg (95% CI: 683, 714 mg) by applying NSRI 2014 targets and by 615 mg (95% CI: 597, 634 mg) by applying Health Canada's 2016 benchmarks. Significant reductions could have occurred, regardless of age, sex, race/ethnicity, income, education, or hypertension status, up to a mean reduction in sodium intake of 850 mg/d in men aged ≥19 y by applying NSRI targets. The proportion of adults aged ≥19 y who consume ≥2300 mg/d would decline from 88% (95% CI: 86%, 91%) to 71% (95% CI: 68%, 73%) by applying NSRI targets and to 74% (95% CI: 71%, 76%) by applying Health Canada benchmarks. Conclusion: If established sodium standards are applied to commercially processed and prepared foods, a significant reduction of US sodium intake could occur. [ABSTRACT FROM AUTHOR]

Winter snow and ice can have a significant impact on our mobility, whether on foot or by car. Alongside plowing, arguably the greatest tool in combating snow and ice is salt. The most commonly used salt for winter maintenance is Sodium Chloride (NaCl), the same salt used in food and water softeners, is applied to roads, sidewalks, and parking lots as it is an effective deicer when temperatures are between 0°C and -12°C. Studies have shown that deicing with salt reduces accidents by 88% and injuries by 85% (Salt Institute 2017). The effectiveness of road salt, as well as its relative affordability, means that as much as four million tonnes may be applied annually in Canada for deicing (Environment Canada 2012). However, while salt is relatively inexpensive to purchase, there are a number of external costs that are becoming increasingly apparent. These include corrosion of vehicles and infrastructure like concrete, bridges, and water mains; damage and staining to the interior and exterior of buildings; impacts to roadside vegetation and soils; and the contamination of fresh water. In fact, the environmental impacts are such that it prompted Environment Canada to propose that winter salt be considered a toxic substance primarily due to the quantity that is applied annually (Environment Canada 2001). The Lake Simcoe watershed, approximately 3,400km2 in size, is situated just 20km north of Toronto, Ontario, with the southern portion of the watershed being considered part of the Greater Toronto Area (GTA), the most populous metropolitan area in Canada. As part of the GTA, the Lake Simcoe watershed has experienced and continues to experience considerable growth, and with this growth comes an increase in the amount of impervious surfaces requiring winter salting. Indeed, chloride has been showing a strong increasing trend in the urban creeks and in Lake Simcoe itself over the last 30 years. Even rural creeks are showing an increasing trend, albeit not as severe, nor are the concentrations of chloride reaching the same levels (LSRCA 2015). The highest chloride level recorded in a Lake Simcoe tributary was 6,120mg/l in the winter of 2013. Chloride guidelines for the protection of aquatic ecosystems utilize a guideline of 120mg/L for chronic exposure and 640mg/L for acute exposure (CCME 2011). While the high value recorded in the Lake Simcoe tributary greatly exceeds these guidelines, it is still drastically lower than values being recorded in larger, intensively urbanized catchments such as Cooksville Creek in Mississauga, Ontario, which sees concentrations in excess of 20,000 mg/L, the concentration of sea water, nearly every winter (Credit Valley Conservation personal comm). Similarly, in July of 2011 a small population of Atlantic blue crabs, a marine species, was found surviving in Mimico Creek in Toronto (Toronto Star: May 26, 2012). That a marine species was able to survive in this fresh water creek in summer demonstrates that the impacts of winter salt are not just limited to winter but are impacting shallow groundwater and thus summer baseflow, maintaining high chloride concentrations year round. The same is being seen in some urban creeks in the Lake Simcoe watershed, with summer baseflow concentrations exceeding the chronic guideline and trending upwards (LSRCA unpublished). While not yet as extreme as rivers in the more densely urbanized parts of the GTA, these examples foreshadow what is in store for Lake Simcoe rivers if current winter salt practices continue along with the projected urban growth. During the winter of 2012 an estimated 99,300 tonnes of salt was applied in the Lake Simcoe watershed, an amount that equals nearly 250kg of salt per capita, or ~3 times the average person's body weight in salt. This estimate was generated through a survey of local road agencies along with the total area of commercial/institutional parking lots within the watershed. The exercise served to highlight a knowledge gap around application practices and rates in commercial/institutional parking lots. The majority of road agencies were found to record annual volumes, application dates and rates whereas literature values range from 10-40% of the salt applied in a catchment come from commercial/institutional parking lots (Perera et al, 2009; Trowbridge et al, 2010; Lake Simcoe Region Conservation Authority, 2015), and a survey of winter maintenance contractors cite an average value of approximately 58g/m2/application (Fu et al, 2013) (Figure 1). While these values were used in the estimation as they were the best available, observational data suggested these may be on the conservative side (Figure 2). Therefore, monitoring of a 14 ha commercial lot was undertaken for the winters of 2014/15, 2015/16, and 2016/17 to better quantify the amount of salt coming from this type of land use. The winters of 2014/15 and 2016/17 saw similar applications of 1,067 and 1,010 tonnes applied respectively, while the mild winter of 2015/16 saw 556 tonnes applied. While the amounts varied somewhat each winter, the impacts downstream were consistent. Maximum concentrations recorded in the melt water reached 3.5 to 4 times the salt concentration of sea water every winter, equating to chloride concentrations of 70,000mg/L to 85,000mg/L; two orders of magnitude above the water quality guideline. As with most parking lots constructed in the last two decades, the runoff from this parking lot is captured in a stormwater pond prior to entering the receiving watercourse. Interestingly, the winter salt also caused persistent chemical stratification in the permanent pool of the pond. The pond was monitored with continuous monitors for the ice free period of 2015 and 2016 (April to December) during which the bottom water chloride concentration remained distinct from the surface chloride concentration, indicating stratification (Figure 3). This has two significant implications; first of which is that this pond, and therefore many other ponds like it, may not be functioning as designed which is leading to diminished performance (McEnroe 2012, Marsalek 2003). Second is that ponds are acting as salt reservoirs, slowly releasing salt year round and contributing to river chloride concentrations that continually exceed the chronic exposure guideline and thereby exposing aquatic life to harmful concentrations during sensitive life cycle stages. To determine the extent to which the catchment land use type impacts stormwater ponds, chemical profiles were measured on three ponds in February 2017. The catchments included the 24.6 ha commercial catchment with 14 ha of salt application surface, an institutional catchment (14.3 ha) with 6 ha of salt application area that includes parking lots and roads, and a 16.4 ha residential catchment with 3 ha of salt application area comprised of tertiary municipal roads. Interestingly, all three ponds showed chemical stratification, with the severity of the stratification and highest chloride concentrations relating to the amount of salt application area in the catchment. The residential pond yielded a maximum chloride concentration of 3,115mg/L in the bottom waters, the institutional yielded 16,144mg/L, and the commercial yielded 25,530 mg/L with chloride concentrations in the bottom 0.5m of the pond exceeding that of sea water. The maximum chloride concentration recorded in the receiving watercourse downstream of the commercial lot was measured at 5,406 mg/L, well in excess of the acute guideline of 640 mg/L. These results highlight that commercial parking lots are not only receiving a significant volume of salt but are also having the most dramatic impacts on receiving stormwater infrastructure and watercourses. [ABSTRACT FROM AUTHOR]

In 2010, as part of a national sodium reduction strategy, Canada published sodium reduction benchmark targets for packaged foods; however, no evaluation of this policy has occurred. The objective was to evaluate changes in the sodium content of packaged foods, identify categories reduced in sodium, and determine the proportion meeting Health Canada's sodium reduction benchmarks. This was a cross-sectional analysis of Canadian packaged foods in 2010 and 2013 ( n = 10 487 and n = 15 394, respectively). Sodium content was obtained from the Nutrition Facts table. Overall, 16.2% of food categories had significantly reduced sodium levels. The greatest shifts in the distribution of sodium within food categories occurred in imitation seafood (mean ± SD, mg/100 g; 602 ± 50 to 444 ± 81, 26.2%, p = 0.002), condiments (1309 ± 790 to 1048 ± 620, 19.9%, p = 0.005), breakfast cereals (375 ± 26 to 301 ± 242, 19.7%, p = 0.001), canned vegetables/legumes (269 ± 156 to 217 ± 180, 19.3%, p < 0.001), plain chips (462 ± 196 to 376 ± 198, 18.6% p = 0.004), hot cereals (453 ± 141 to 385 ± 155, 15.0%, p = 0.011), meat analogues (612 ± 226 to 524 ± 177, 14.4%, p = 0.003), canned condensed soup (291 ± 62 to 250 ± 57, 14.1%, p = 0.003), and sausages and wieners (912 ± 219 to 814 ± 195, 10.7%, p = 0.012). The proportion of foods meeting at least 1 of the 3 phases of the sodium reduction benchmark targets slightly increased (51.4% to 58.2%) and the proportion exceeding maximum benchmark levels decreased (25.2% to 20.8%). These data provide a critical evaluation of changes in sodium levels in the Canadian food supply. Although progress in reducing sodium in packaged foods is evident, the food industry needs to continue efforts in reducing the sodium in the foods they produce. [ABSTRACT FROM AUTHOR]

The Paleoproterozoic Athabasca Basin (Canada) hosts numerous giant unconformity-related uranium deposits. The scope of this study is to establish the pressure, temperature, and composition (P-T-X conditions) of the brines that circulated at the base of the Athabasca Basin and in its crystalline basement before, during and after UO deposition. These brines are commonly sampled as fluid inclusions in quartz- and dolomite-cementing veins and breccias associated with alteration and U mineralization. Microthermometry and laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) data from five deposits (Rabbit Lake, P-Patch, Eagle Point, Millennium, and Shea Creek) complement previously published data for the McArthur River deposit. In all of the deposits investigated, fluid inclusion salinity is between 25 and 40 wt.% NaCl equiv., with compositions displaying a continuum between a 'NaCl-rich brine' end-member (Cl > Na > Ca > Mg > K) and a 'CaCl-rich brine' end-member (Cl > Ca ≈ Mg > Na > K). The CaCl-rich brine has the highest salinity and shows evidence for halite saturation at the time of trapping. The continuum of compositions between the NaCl-rich brine and the CaCl-rich brine end-members combined with P-T reconstructions suggest anisothermal mixing of the two brines (NaCl-rich brine, 180 ± 30 °C and 800 ± 400 bars; CaCl-rich brine, 120 ± 30 °C and 600 ± 300 bars) that occurred under fluctuating pressure conditions (hydrostatic to supra-hydrostatic). However, because the two brines were U bearing and therefore oxidized, brine mixing was probably not the driving force for UO deposition. Several scenarios are put forward to account for the Cl-Na-Ca-Mg-K composition of the brines, involving combinations of seawater evaporation, halite dissolution, mixing with a halite-dissolution brine, Mg/Ca exchange by dolomitization, Na/Ca exchange by albitization of plagioclase, Na/K exchange by albitization of K-feldspar, and Mg loss by Mg-rich alteration. Finally, the metal concentrations in the NaCl-rich and CaCl-rich brines are among the highest recorded compared to present-day sedimentary formation waters and fluid inclusions from basin-hosted base metal deposits (up to 600 ppm U, 3000 ppm Mn, 4000 ppm Zn, 6000 ppm Cu, 8000 ppm Pb, and 10,000 ppm Fe). The CaCl-rich brine carries up to one order of magnitude more metal than the NaCl-rich brine. Though the exact origin of major cations and metals of the two brines remains uncertain, their contrasting compositions indicate that the two brines had distinct flow paths and fluid-rock interactions. Large-scale circulation of the brines in the Athabasca Basin and Basement was therefore a key parameter for metal mobility (including U) and formation of unconformity-related U deposits. [ABSTRACT FROM AUTHOR]

The average salt intake of people in Canada, the United States, and Europe is about 3,400mg of sodium per day, which exceeds the recommended intake levels set by various health organizations. The World Health Organization recommends a worldwide reduction of sodium intake to less than 2,000mg per day. Most research to date has focused on the negative effects of high-sodium intake; however, little information is available on the metabolic effects of low-sodium intakes. This review focuses on the hormonal changes associated with low-sodium diets, specially the hormones involved in metabolism and cardiovascular and renal function. Based largely on rodent studies, low-sodium diets have been associated with changes in glycemic control, energy metabolism, cardiovascular disease risk, cholesterol concentrations, inflammation, and functioning of the renin-angiotensin-aldosterone system. Overall, research has revealed mixed results regarding the impact of dietary sodium intake on various hormones. Further research is required to assess the effects of sodium reduction on hormones and their associated pathways in order to determine the likelihood of any unintended effects. [ABSTRACT FROM AUTHOR]

Despite an overall increase in total road salt used over the past 14 years (the data record in this manuscript), there has been a 26% reduction in the rate (normalized as tonnes of salt per cm of snow per km of road) of road salt application by the City of Toronto since that city implemented mitigations from the Road Salt Code of Practice. The ecological benefit of the reduced use of road salt was approximated by comparing the estimated 26% salt reduction to the distribution of chloride tolerances that has been recently published by the Canadian Council of Ministers of the Environment (i.e., CCME). Species sensitivity distributions predict that between 1 and 14% of taxa would benefit from a 26% reduction in chloride concentrations in surface waters. Assuming that a typical 'healthy' Canadian watercourse might support between 100 and 200 species of fish, invertebrates and plants, the Code of Practice might provide benefit to between 14 and 28 species. However, the net ecological benefit of implementing the Code may be undermined in rapidly urbanizing watersheds where road networks continue to expand at a rate of 3-5% per year and chloride loads to urban streams are steadily increasing. [ABSTRACT FROM AUTHOR]

Background: Sodium-related claims on food labels should facilitate lower-sodium food choices; however, consumer attitudes and understanding of such claims are unknown. Objectives: We evaluated consumer attitudes and understanding of different types of sodium claims and the effect of having hypertension on responses to such claims. Design: Canadian consumers (n = 506), with and without hypertension, completed an online survey that contained a randomized mock-package experiment, which tested 4 packages that differed only by the claims they carried as follows: 3 sodium claims (disease risk reduction, function, and nutrient-content claims) and a tastes-great claim (control). Participants answered the same questions on attitudes and understanding of claims after seeing each package. Results: Food packages with any sodium claim resulted in more positive attitudes toward the claim and the product healthfulness than did packages with the taste control claim, although all mock packages were identical nutritionally. Having hypertension increased ratings related to product healthfulness and purchase intentions, but there was no difference in reported understanding between hypertensives and normotensives. In general, participants attributed additional health benefits to low-sodium products beyond the well-established relation of sodium and hypertension. Conclusions: Sodium claims have the potential to facilitate lower-sodium food choices. However, we caution that consumers do not seem to differentiate between different types of claims, but the nutritional profiles of foods that carry different sodium claims can potentially differ greatly in the current labeling environment. Additional educational efforts are needed to ensure that consumers do not attribute inappropriate health benefits to foods with low-sodium claims. This trial was registered at clinicaltrials.gov as NCT01764724. [ABSTRACT FROM AUTHOR]

Abstract: Analyses of halogen concentration and stable chlorine isotope composition of fluid inclusions from hydrothermal quartz and carbonate veins spatially and temporally associated with giant unconformity-related uranium deposits from the Paleoproterozoic Athabasca Basin (Canada) were performed in order to determine the origin of chloride in the ore-forming brines. Microthermometric analyses show that samples contain variable amounts of a NaCl-rich brine (Cl concentration between 120,000 and 180,000ppm) and a CaCl2-rich brine (Cl concentration between 160,000 and 220,000ppm). Molar Cl/Br ratios of fluid inclusion leachates range from ∼100 to ∼900, with most values between 150 and 350. Cl/Br ratios below 650 (seawater value) indicate that the high salinities were acquired by evaporation of seawater. Most δ37Cl values are between −0.6‰ and 0‰ (seawater value) which is also compatible with a common evaporated seawater origin for both NaCl- and CaCl2-rich brines. Slight discrepancies between the Cl concentration, Cl/Br, δ37Cl data and seawater evaporation trends, indicate that the evaporated seawater underwent secondary minor modification of its composition by: (i) mixing with a minor amount of halite-dissolution brine or re-equilibration with halite during burial; (ii) dilution in a maximum of 30% of connate and/or formation waters during its migration towards the base of the Athabasca sandstones; (iii) leaching of chloride from biotites within basement rocks and (iv) water loss by hydration reactions in alteration haloes linked to uranium deposition. The chloride in uranium ore-forming brines of the Athabasca Basin has an unambiguous dominantly marine origin and has required large-scale seawater evaporation and evaporite deposition. Although the direct evidence for evaporative environments in the Athabasca Basin are lacking due to the erosion of ∼80% of the sedimentary pile, Cl/Br ratios and δ37Cl values of brines have behaved conservatively at the basin scale and throughout basin history. [Copyright &y& Elsevier]

Abstract: In North America, corrosion of the steel rebar commonly occurs due to chloride attack from deicing salts. In Canada, based on the severity and temperature of the ambient environment, three different deicing salts, or combination of them, are used: NaCl, MgCl2 and CaCl2. In this paper, the effect of each of these salts on the corrosion of steel rebar and their impact on the durability of the mortar have been investigated. The results show that CaCl2 has the most negative effect on the steel and, in high concentrations, on the integrity of the mortar. MgCl2 also deteriorates the mortar if used in high concentration, while NaCl has no apparent effect on mortar durability even in high concentration. [Copyright &y& Elsevier]

A field investigation involving snow coring, surveying, and melt water collection was undertaken at a city snow storage facility to characterize the snow and melt water in Edmonton, Alberta, Canada. The investigation revealed a high content of both salts and sediment within the snow, a pile volume of 500,000 m3, a snow density of 0.63–0.83 g/cm3, and an average road salt content of 1.2 g/L within the melted snow. The salt within the Poundmaker snow pile, one of Edmonton’s five snow storage sites, represented approximately 1.5–2.0% of the total amount of salt that was used on the city roads during the 2006/2007 winter. Melt water fractionation took place on-site during the spring melt and salt concentrations in the March melt water (early spring) were often more than 10 times the concentration of the bulk snow. Some of the factors affecting the snow and melt water composition included the snow retention time on streets, snow source, weather/climate, sampling technique, and snow site characteristics/operations. [ABSTRACT FROM AUTHOR]

Abstract: The quantity of deicing salt applied to paved surfaces in urban watersheds in cold regions has had a significant and cumulative effect on groundwater quality. Whereas road deicing salt is known in general to impact groundwater and surface water quality, quantitative information on the impact of large transport routes is lacking. In this study, we provide a chloride mass balance for an urban stream crossed by a large transport route in south-central Ontario, Canada and quantify likely long-term impacts of salt loading on surface and groundwater resources. The chloride mass balance, supported by hydrochemical analysis, reveals that approximately 50% of the total road salt applied to Pine Creek (1700 tonnes per winter) is removed annually via overland flow with the remainder accumulating in the shallow subsurface resulting in severe degradation of groundwater quality. Moreover, results show that road salt migration is the primary reason for enhanced mineral weathering in the shallow aquifer. During the 2004–05 salting season, runoff and baseflow transport of road salts were responsible for chloride concentrations in the stream of up to 2000 mg L−1, and delivered approximately 850 tonnes of chloride (about 1400 tonnes of salt) to a shallow (<3.5 m) semi-enclosed lagoon on the shore of Lake Ontario (Frenchman''s Bay; 0.85 km2). The total chloride delivery to the lagoon from its entire watershed is estimated at 3700 tonnes each year with up to 48% of the total load delivered by baseflow, the remainder from surface water runoff. Present day groundwater chloride concentrations are estimated to be about 80% of long-term concentrations when the system reaches steady state. [Copyright &y& Elsevier]

North America''s fifth most populated municipality — the Greater Toronto Area (GTA) — is undergoing rapid urban development with serious questions being raised regarding the long-term impacts of urban growth on the quality and quantity of ground and surface water. Degradation of groundwater quality by NaCl de-icing salt is the primary concern since there are no cost effective alternatives to NaCl de-icing salt and there is little evidence that salt loadings to the subsurface can be significantly reduced. In 2001, the issue acquired a new sense of urgency when de-icing chemicals containing inorganic chloride salts (with or without ferrocyanide de-caking agents) were designated as toxic under the Canadian Environmental Protection Act. To heighten concerns, future growth in the GTA will inevitably take place in areas where groundwater is regularly used for potable supply. Studies using groundwater flow and transport models show that significant deterioration of groundwater quality can be expected in shallow aquifers as a result of urban development with chloride concentrations approaching the drinking water quality standard of 250 mg/l. Results demonstrate that urban planning needs a fresh approach that explicitly includes groundwater protection and aquifer management in the decision-making process, clearly defines acceptable environmental performance standards and makes greater use of groundwater models to evaluate alternative urban designs. [Copyright &y& Elsevier]

Abstract: We derive a thermodynamic model useful for calculating the partitioning of gases in brine–oil closed systems. We assumed real binary mixtures of all components, and solved a set of equilibrium equations relating the solubility of gases in brines to the solubility of gases in petroleum liquids. We applied the model to understand the distribution of gases in the IEA-GHG Weyburn CO2 Monitoring and Storage Project, in Saskatchewan, Canada, throughout the first and second year after commencement of CO2 injection. Results indicate that a free-gas phase formed in the south-east of the field ∼363 days after injection, which increased in size and volume with time, but did not correlate with zones showing excess CO2 production. We also observed overlaps between areas of 13C depleted HCO3 − and areas with free-vapor phase. We conclude that gas injection leads to short-term CO2 dissolution in liquids, followed by the creation of a CO2-rich vapor phase. [Copyright &y& Elsevier]

Hypersaline brines of marine origin, deep within fractured crystalline rocks of the Canadian Shield, are characterized by calcium-chloride compositions with relatively low concentrations of magnesium and sulphate. Such chemistries among crustal fluids are very unusual, regardless of their origins, which makes it difficult to identify possible genetic associations between shield brines and other marine brines. Key conservative chemical and isotopic attributes of shield brines from the Yellowknife and Sudbury areas are similar, however, to those of fluid inclusions in sparry, late-stage hydrothermal dolomites in lower Paleozoic carbonates of the Western Canada Sedimentary Basin, suggesting that both fluid types originated from a residual seawater brine of probable Devonian age. This interpretation is supported by determination of a helium-4 model age for the Yellowknife brine that is consistent with a Devonian origin. Therefore, dolomitization was likely both a major source of Ca and a sink for about half of the initial Mg in the brine prior to its infiltration into the underlying basement rocks. Mass-balance considerations indicate that albitization of plagioclase, predominantly in basinal clastic sediments, was an equally important mineral source of Ca to the infiltrating brine, but interactions with carbonate and silicate rocks cannot account for the entire Ca inventory in the brine. A major contribution to the Ca budget must also have been initially provided by the evaporative concentration of seawater, which is only possible if it were enriched in calcium and depleted in sulphate compared with modern seawater, as was probably the case during Devonian time. [ABSTRACT FROM AUTHOR]

Examines the continuing debate over salt intake and its effect on human health. New recommendations for a reduced salt intake from the Institute of Medicine of the National Academies in the United States; Amount of salt needed for survival; Results from a recent Canadian research group which made a different recommendation; How the issue could cause entire industries to change the way they do business; Most sodium content which is found in processed foods; Canadians who charge the American study was not representative of the population; Effects of low sodium on the human body.

Copyright of Atmosphere - Ocean (Canadian Meteorological & Oceanographic Society) is the property of Canadian Meteorological & Oceanographic Society and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Sodium Reduction Strategy for Canada includes an identification of priority areas for future research, based on a workshop convened by the Canadian Institutes of Health Research (CIHR) and partners. A strong portfolio of research is essential to addressing current developments and controversies raised in relation to the health outcomes associated with dietary sodium. CIHR aims to provide leadership in working together with other funders and partners to catalyze a broad range of sodium research. [ABSTRACT FROM AUTHOR]

Accidental IV administration of heparinized irrigation solution occurs frequently. Two cases from ISMP Canada offer some safe practice recommendations. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Canada's Saltworks Technologies is helping Standard Lithium – a speciality chemical company that focuses on unlocking the value of existing large-scale US-based lithium-bearing brine resources – to produce high-purity lithium carbonate. [ABSTRACT FROM AUTHOR]

Canada's Saltworks, which develops technology for industrial desalination, brine treatment and zero liquid discharge (ZLD), is entering the water treatment market place in China and is set to establish its local headquarters at the International Water Hub (IWH), located on the Singapore Nanjing Eco Hi-tech Island (SNEI). [ABSTRACT FROM AUTHOR]

This review aims to summarize and synthesize studies reporting on changes in sodium levels in packaged food products, restaurant foods, and hospital or school meals, as a result of salt reduction interventions. Studies were extracted from those published in the Science of Salt Weekly between June 2013 and February 2018. Twenty-four studies were identified: 17 assessed the changes in packaged foods, four in restaurant foods, two in hospital or school meals, and one in both packaged and restaurant foods. Three types of interventions were evaluated as part of the studies: voluntary reductions (including targets), labeling, and interventions in institutional settings. Decreases in sodium were observed in all studies (n = 8) that included the same packaged foods matched at two time points, and in the studies carried out in hospitals and schools. However, there was little to no change in mean sodium levels in restaurant foods. The pooled analysis of change in sodium levels in packaged foods showed a decrease in sodium in unmatched food products (-36 mg/100 g, 95% CI -51 to -20 mg/100 g) and in five food categories-breakfast cereals, breads, processed meats, crisps and snacks, and soups. Twenty-two of the 24 studies were from high-income countries, limiting the applicability of the findings to lower resource settings., (©2019 Wiley Periodicals, Inc.)

The 2013 Institute of Medicine report entitled "Sodium Intake in Populations: Assessment of Evidence" found inconsistent evidence of health benefit with dietary sodium intake <2300 mg/d. Different studies reported benefit and harm of population dietary intake <2300 mg/d. The Institute of Medicine committee, however, did not assess whether the methodology used in each of the studies was appropriate to examine dietary sodium and health outcomes. This review investigates the association of methodological rigor and outcomes of studies in the Institute of Medicine report. For the 13 studies that met all methodological criteria, nine found a detrimental impact of high sodium consumption on health, one found a health benefit, and in three the effect was unclear (P = .068). For the 22 studies that failed to meet all criteria, 11 showed a detrimental impact, four a health benefit, and seven had unclear effects from increasing dietary sodium (P = .42)., (©2018 Wiley Periodicals, Inc.)

The article focuses on the recommendations issued by the Sodium Working Group of Health Canada for curbing the high salt consumption of Canadians. It says that the Sodium Reduction Strategy calls on restaurants and food manufacturers to reduce the sodium content of their products, and on Health Canada to monitor their compliance. Moreover, Federal Minister of Health Leona Aglukkaq released a statement stating that Health Canada will consult its partners to examine the recommendations.

The article presents a reprint of the article "Sifting for salt strategies from the Sodium Working Group," by Becky Rynor which appeared on October 7, 2009 at www.cmaj.ca. It notes the strategy of Sodium Working Group (SWG) of Health Canada to limit the consumption of salt. However, Blaise Ouattara of Canadian Meat Council says that there should have an option to control bacterial growth if salt will be reduced.

Discusses the abstract of the article "In vitro effects of salt compounds on radial growth, sporulation, and spore germination of postharvest potato diseases," by A.A.S. Mills, H.W. Platt, R.A.R. Hurta and R.A. MacPhail, submitted to the 2003 Canadian Phytopathological Society Annual Meeting in Montreal, Quebec.