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Municipal water supply through truck-to-cistern systems is common in northern Canada. Household satisfaction and concerns about water services likely impact user preferences and practices. This case study explores household perspectives and challenges with regard to domestic access to water in a decentralized truck-to-cistern system. A case study was conducted in the Northern Village of Kangiqsualujjuaq, Nunavik (Quebec, Canada). A paper-based questionnaire was completed by 65 households (one quarter of the population). Many households (37%) reported not drinking tap water from the truck-to-cistern system. Chlorine taste was a frequently reported concern, with those households being significantly less likely to drink water directly from the tap (p = 0.002). Similarly, households that reported a water shortage in the previous week (i.e., no water from the tap at least once) (33%) were more likely to express dissatisfaction with delivered water quantity (rs = 0.395, p = 0.004). Interestingly, 77% of households preferred using alternative drinking water sources for drinking purposes, such as public tap at the water treatment plant, natural sources or bottled water. The study underscores the importance of considering household perspectives to mitigate the risks associated with service disruptions and the use of alternative sources for drinking purposes. [ABSTRACT FROM AUTHOR]

Understanding lead exposure pathways is a priority because of its ubiquitous presence in the environment as well as the potential health risks. We aimed to identify potential lead sources and pathways of lead exposure, including long-range transport, and the magnitude of exposure in Arctic and subarctic communities. A scoping review strategy and screening approach was used to search literature from January 2000 to December 2020. A total of 228 academic and grey literature references were synthesised. The majority of these studies (54%) were from Canada. Indigenous people in Arctic and subarctic communities in Canada had higher levels of lead than the rest of Canada. The majority of studies in all Arctic countries reported at least some individuals above the level of concern. Lead levels were influenced by a number of factors including using lead ammunition to harvest traditional food and living in close proximity to mines. Lead levels in water, soil, and sediment were generally low. Literature showed the possibility of long-range transport via migratory birds. Household lead sources included lead-based paint, dust, or tap water. This literature review will help to inform management strategies for communities, researchers, and governments, with the aim of decreasing lead exposure in northern regions. [ABSTRACT FROM AUTHOR]

The Saskatchewan River Basin (SRB) of central Canada plays a crucial role in the Canadian Prairies. Yet, climate change and human action constitute a real threat to its hydrological processes. This study aims to evaluate and analyze groundwater spatial and temporal dynamics in the SRB. Groundwater information was derived and compared using two different approaches: (1) a mathematical modeling framework coupling the Soil and Water Assessment Tool (SWAT) and the Modular hydrologic model (MODFLOW) and (2) gravimetric satellite observations from the Gravity Recovery and Climate Experiment (GRACE) mission and its follow-on (GRACE-FO). Both methods show generalized groundwater depletion in the SRB that can reach −1 m during the study period (2002–2019). Maximum depletion appeared especially after 2011. The water balance simulated by SWAT-MODFLOW showed that SRB could be compartmented roughly into three main zones. The mountainous area in the extreme west of the basin is the first zone, which is the most dynamic zone in terms of recharge, reaching +0.5 m. The second zone is the central area, where agricultural and industrial activities predominate, as well as potable water supplies. This zone is the least rechargeable and most intensively exploited area, with depletion ranging from +0.2 to −0.4 m during the 2002 to 2011 period and up to −1 m from 2011 to 2019. Finally, the third zone is the northern area that is dominated by boreal forest. Here, exploitation is average, but the soil does not demonstrate significant storage power. Briefly, the main contribution of this research is the quantification of groundwater depletion in the large basin of the SRB using two different methods: process-oriented and satellite-oriented methods. The next step of this research work will focus on the development of artificial intelligence approaches to estimate groundwater depletion from a combination of GRACE/GRACE-FO and a set of multisource remote sensing data. [ABSTRACT FROM AUTHOR]

Water is central to Haudenosaunee knowledge, philosophy, and culture. The health of Haudenosaunee mothers is tied to that of water. Today, the lack of access to reliable drinking water for Six Nations is a significant health concern. Technical measurement of water advisories in Canada fails to understand the interwoven relationship that Haudenosaunee women have with water. Highlighting the voices of 55 Haudenosaunee women, we provide expanded definitions of water insecurity and maternal health to include more-than-human beings. This comprehensive understanding of water insecurity and health shapes SN mothers' experiences with water in a settler colonial state, affecting their holistic wellbeing. [ABSTRACT FROM AUTHOR]

While most Canadians have access to potable drinking water, those without are overwhelmingly Indigenous people living on reserves, constituting a racialised form of water injustice. Suicide rates for First Nations are also disproportionate to the general population, but lessor known is the relationship of suicide in communities experiencing long-term drinking water advisories. In this paper, drawing on Indigenous feminist conceptualisations of affect, I consider the affective relationship between long-term water advisories, suicide, and hydrocolonialism. I argue that long-term drinking water advisories are a kind of somatechnic that elucidate the hydrocolonial and necropolitical states of exception that threaten and devalue Indigenous life. Under such somatechnics, I work with the analytic of felt theory, to understand the hydrocolonial affects at play in the prevalence of suicide in communities experiencing long-term water advisories. By making felt the necropolitical connections between bodies of water and the bodies of suicidal people, these affects upend dominant claims about suicide, and invite us towards more fulsome structural analyses of suicide, more agentic renderings of suicidal people, and more politically enlivened ways of addressing suicide. Finally, hydrocolonial affects invite consideration of the possibilities of care and resistance for human and older-than-human relations. In summary, this paper theorises the hydrocolonial affects produced by dead and dying water and suicidal people as a profound challenge to the settler colonial state, and an invitation to produce futures committed to liveability. [ABSTRACT FROM AUTHOR]

Drinking water, wastewater, and stormwater are three components of an Urban Water System. Maintenance of these components requires evaluation of the existing performance of the water system. The evaluation becomes more significant in small and medium-sized water systems because these systems wrestle with various constraints, such as insufficient funds, inadequate infrastructure and water governance. In this study, Key Performance Indicators (KPIs) are identified for each UWS component considering six performance criteria. A questionnaire was distributed to water utilities across the Okanagan Valley. KPIs were identified by combining Delphi technique and Preference Ranking Organization Method for Enrichment Evaluation methods. Ninety-six KPIs were identified with 39, 30, and 27 KPIs for drinking water, wastewater, and stormwater. Based on the available literature, agriculture water use, low impact development implementation (LID), average annual life cycle investment, and swimming advisories are a few notable KPIs that are unique to the Valley. [ABSTRACT FROM AUTHOR]

Water distribution networks (WDNs) are complex interconnected networks that require extensive planning and maintenance to ensure good quality water is delivered to all consumers. The main task of WDNs is to provide consumers with a minimum acceptable level of supply (in terms of pressure, availability, and water quality) at all times under a range of operating conditions. However, the water infrastructure in North America signifies an urgent need of upgrading the aging and deteriorating distribution systems if they are to continue to provide consumers with reliable and safe water supplies. In this context, this research is proposing a new reliability model for assessing the mechanical/structural as well as hydraulic conditions of a WDN to identify failure-prone components and prioritize their renewal. The developed model provides a systematic and practical methodology to calculate the mechanical/structural reliability of the pipe and its accessories (valves, hydrants, and so on) through the consideration of historical failures of components. The research deployed pressure-dependent demand analysis to determine the hydraulic reliability of the network in meeting the pressure requirements and overall hydraulics of the network. The minimum-cut-set theory was implemented in both reliability assessments, and the outputs of the two models were integrated to provide a representative reliability of the network. A sensitivity analysis was followed to study the change in segments' attributes on the mechanical/structural and hydraulic reliabilities. The approach was implemented on the City of London, Canada, network (north and south) to test its applicability. The developed model is expected to assist decision makers in integrating the failure records with the hydraulic simulation to plan for optimum intervention actions. [ABSTRACT FROM AUTHOR]

Drawing on three cases of long-term Indigenous–settler alliances in Canada, this research investigates the roles and contributions of settlers towards decolonization. As a multidisciplinary team of Indigenous and non-Indigenous scholars, our research goal has been to understand how such alliances endure and change over time, and how they negotiate power dynamics, tensions and changes, within a settler colonial context. Taking a comparative case study approach, and analysing interviews, sharing circles and archival documents, we focus here on the lessons that alliance participants have learned from their activist experiences about settler roles and responsibilities. The three cases include (1) The Right to Belong: Indigenous women's organizing and the struggle to eliminate sex discrimination in the Indian Act; (2) Shoal Lake 40 First Nation's Freedom Road campaign to end a century of state-imposed geographic isolation and to secure access to safe drinking water; and (3) the alliance-building and solidarity activism of Canadian ecumenical social justice coalitions now under the umbrella of KAIROS Canada. While none of these campaigns alone equates to decolonization in the sense of land return and Indigenous sovereignty, each has helped create the conditions, relationships and transformations in settler consciousness that may provide the ground for decolonization. Taken together, the three case studies illustrate the contingent environments in which alliances are forged and the ways in which settlers take up particular responsibilities based on Indigenous-defined goals. [ABSTRACT FROM AUTHOR]

Consumption of local and imported bottled water in Canada has greatly increased during the past three decades. While the presence of natural radioactivity is often overlooked when dealing with the water quality of these bottled products, it could contribute substantially to the uptake of radionuclides especially when sourced from regions with higher radioactivity levels compared to where it is consumed. In this study, the activity of several naturally occurring radionuclides (i.e., 210Po, 226,228Ra, 230,232Th, 234,235,238U) were measured in bottled water available in Québec, Canada after sample pretreatment and analysis by either radiometric or mass spectrometry approaches. 230,232Th and 228Ra concentrations were below minimum detectable activity levels in all samples tested. Analytical results for 234U, 235U, 238U, and 226Ra showed concentrations that ranged from 0.38 to 115 mBq/L, (2.2–313) x 10−2 mBq/L, 0.48–58.4 mBq/L, and 1.1–550 mBq/L, respectively. 210Po was detected in only 5 samples and its activity ranged from 2 to 26 mBq/L. To determine variability in activity within brands, the same brands of bottled water were purchased during two consecutive years and analyzed. The possible radiological impact of the consumption of these types of water was assessed based on different drinking habit scenarios. Some of the imported water brands showed higher activity concentrations than local sources or tap water, suggesting that individuals drinking predominantly imported bottled water would receive a higher radiation dose than those who drink mainly local water. • Naturally occurring radionuclides (210Po, 226Ra, 228Ra 230Th, 232Th, 234U, 235U and 238U) were measured in 15 bottled water brands available in Québec City, as well as in municipal tap water. • Temporal analyses were done by sampling the bottled water in two separate periods in two consecutive years. • The analyses revealed variations in U and Ra activities, demonstrating the need to routinely monitor each radionuclide. • In most samples, 226Ra was the major contributor to dose and calculated committed doses were systematically higher for younger individuals. [ABSTRACT FROM AUTHOR]

Drinking water insecurity in small and rural, remote, or otherwise marginalized communities in Canada is pervasive and complex with multiple dimensions and impacts. These communities face challenges such as variable source water quality, lack of resources, inappropriate treatment technologies, lack of access to training, difficulties retaining qualified personnel, and ineffective governance structures. Currently, there is a gap in the academic literature with respect to drinking water security assessment frameworks or tools for small and rural, remote, or otherwise marginalized communities, particularly in high income countries. Thus, the objective of this study is to introduce a framework for assessing drinking water security, from headwater to consumer, in the context of small and rural, remote, or otherwise marginalized communities. An indicator-based framework has been developed to evaluate drinking water security, prioritize actions and investments, and support decision-making. The framework builds on expert knowledge and a critical review of security, sustainability, and performance indices of water supply and treatment processes obtained from the literature. The framework is organised into four dimensions of drinking water security from headwaters to consumer: upstream watershed security; source water security; community needs and engagement; and treatment and distribution infrastructure. A list of relevant indicators for each dimension has been compiled to support framework application in a format that is accessible to decision-makers in small and rural, remote, or otherwise marginalized communities. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Animal 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.)

Foci of high seroprevalence against Toxoplasma gondii are observed in Nunavik, the Inuit land of Northern Quebec (Canada). Considering the rare occurrence of felids in the region, exposure is suspected to be driven by water‐ and food‐borne transmission routes. Hypotheses were that drinking untreated water from natural sources and eating country food mostly raw increased the risk of exposure to the parasite. Data from 1,300 Inuit participants of the 2017 Nunavik Health Survey were included in three weighted robust Poisson regression models. The effect of three types of exposure variables: (1) water treatment (yes/no) and if country food was mostly eaten raw (yes/no); (2) main source of drinking water (bottled/municipal/natural) and frequency of country food consumption (continuous) and (3) drinking water risk (low/intermediate/high) and frequency of a raw country food consumption (continuous), on the presence of Toxoplasma antibodies were estimated. Models were adjusted for age, sex and ecological region, with multiple sensitivity analyses being performed. Toxoplasma gondii seroprevalences were consistently correlated with age quadratically, sex (prevalence ratio = PRwoman/man ranged from 1.18 to 1.22), ecological region (PRHudsonBay/HudsonStrait ranged from 2.18 to 2.41; PRHudsonBay/UngavaBay ranged from 1.52 to 1.59) and consuming bivalve mollusc/urchin (PR varied from 1.02 to 1.21) across all three models. Each increase of two consumptions per month of beluga (PR ranged from 1.01 to 1.03), seal liver (PR ranged from 1.01 to 1.02) and goose (PR ranged from 1.01 to 1.02) were also associated with seropositivity, albeit more clearly in models 2 and 3, while drinking water mainly from natural (PR of 1.47) or municipal (PR = 1.42) sources compared to bottled water, was correlated with seroprevalence, although results were compatible with the null. Our results suggest that both the oocyst‐ (mollusc/urchin, drinking water) and cyst‐borne (walrus, seal liver and goose) transmission pathways could be present in Nunavik. [ABSTRACT FROM AUTHOR]

Urbanization increases the land surface temperature through surface mineralization, adversely affecting vegetation and enhancing the urban heat island (UHI) effect. Global climate change has intensified this warming effect with more frequent and intense heatwaves during hot seasons. While these transformations influence soil temperature, their consequences on drinking water temperature within the drinking water distribution system (DWDS) remains poorly understood. Literature proposes to increase pipe burial depths to mitigate drinking water heating during summer. In this study, we monitored drinking water temperatures in a DWDS in Montreal, Canada with deeply buried pipes (average 1.8 m) during the summer of 2022, focusing on two contrasting zones in terms of UHI and green coverage. Monitoring revealed a 8°C heating effect compared to the water treatment plant, attributed to low green coverage and anthropogenic heat. Conversely, the greener zone exhibited cooler drinking water temperatures, reaching a maximum cooling effect of 8°C as compared to the temperature at the exit of the water treatment plant. Utilizing a soil and water temperature model, we predicted drinking water temperatures within the DWDS with acceptable accuracy. Soil temperature modeling results aligned well with measured water temperatures, highlighting DWDS water temperature approaching its surrounding soil temperature fairly quickly. Despite heatwaves, no immediate correlation emerged between air temperature records and measured water temperatures, emphasizing soil temperature as a superior indicator. An increase in water age displayed no correlation with an increase in measured water temperature, underscoring the dominant influence of UHI and green coverage on water temperature. These findings highlight the cooling advantages of green spaces during summer, providing valuable insights for sustainable urban planning., Competing Interests: Declaration of competing interest The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results., (Copyright © 2024. Published by Elsevier Ltd.)

The Isotrace CNRS workgroup in collaboration with National Research Council of Canada has characterized a number of trace element mass fractions and isotope ratios currently not certified in AQUA-1 natural drinking water reference material (NRC Canada). This survey further expands the use of this material as a tool for environmental quality control, method validation, and method development tool for the international community. Simultaneously, the SLRS-6 river water was analyzed as quality control and also in order to compare both water characteristics, which were sampled in the same area but having undergone different treatment. Mass fractions for B, Cs, Li, Ga, Ge, Hf, Nb, P, Rb, Rh, Re, S, Sc, Se, Si, Sn, Th, Ti, Tl, W, Y, Zr, REEs, and six isotopic ratios are proposed for Sr and Pb. Measurements were mostly performed using ICP-MS with various calibration approaches. The results are reported as consensus or indicative values depending on the number of available datasets, with their associated uncertainties. [ABSTRACT FROM AUTHOR]

Water consumption worldwide has increased considerably in recent decades and has a growing trend due to population growth in the coming years. Migration of the population from rural areas to urban areas will lead to problems arising from water insufficiency in crowded areas. Urban areas are oftentimes up to 8°F warmer than the surrounding rural area, creating “urban heat islands”. In densely populated areas where more water is consumed, an important consideration would be whether a part of the urban water requirement can be covered by rainwater harvesting. First, rainwater harvesting helps to conserve water by reducing the amount of water needed for toilet (and urinal) flushing, and outdoor watering. The article analyzes the water consumption averaged between years 2015 and 2017 (thermal power plants, humidifiers, and plumbing) for a 25- stories building located in Canada. Based on the analysis, it was found that the combined seasonal average for the spring and summer was 62% higher than the winter and fall seasons. By using rainwater instead of potable (drinking) water for these applications, homeowners can reduce their daily water use by approximately 30%. [ABSTRACT FROM AUTHOR]

Boron is an essential mineral for plants, and as such, is a normal dietary constituent for humans. Humans may be naturally exposed to boron through food and drinking water, or via anthropogenic sources such as consumer products. The World Health Organisation established an acceptable safe range of population mean intakes for boron of 1–13 mg/day. Most studies of dietary boron intake show a range of 1–2 mg/day. Consumer products have been estimated to contribute a geometric mean daily intake of 0.1 mg to total boron exposure; however, there are few published surveys of consumer exposure to boron from use of cleaning products. The Government of Canada published a draft screening assessment report of boric acid, its salts and precursors that included estimates of consumer exposure to boron found as ingredients in consumer products. The manufacturers of consumer cleaning products conducted a survey of boron content of current products and estimated exposure using the publicly available exposure tool ConsExpo Web. Dermal exposures to boron during cleaning product use were estimated to result in annual internal exposures ranging from ≪0.001 to 0.36 μg/kg bw/day based on dermal absorption of 0.5%. Using a conservative point of departure for hazard assessment (2,900 μg boron/kg bw/day), estimated margins of exposure for dermal exposures to boron from cleaning product use range from 8,056 to >1,000,000. This work demonstrates that exposure to boron from cleaning product use is very low and essentially insignificant when compared to other (e.g. dietary) sources of boron intake by Canadian consumers. [ABSTRACT FROM AUTHOR]

Background: Fluoride from dietary and environmental sources may concentrate in calcium-containing regions of the body such as the pineal gland. The pineal gland synthesizes melatonin, a hormone that regulates the sleep-wake cycle. We examined associations between fluoride exposure and sleep outcomes among older adolescents and adults in Canada.Methods: We used population-based data from Cycle 3 (2012-2013) of the Canadian Health Measures Survey. Participants were aged 16 to 79 years and 32% lived in communities supplied with fluoridated municipal water. Urinary fluoride concentrations were measured in spot samples and adjusted for specific gravity (UFSG; n = 1303) and water fluoride concentrations were measured in tap water samples among those who reported drinking tap water (n = 1016). We used multinomial and ordered logistic regression analyses (using both unweighted and survey-weighted data) to examine associations of fluoride exposure with self-reported sleep outcomes, including sleep duration, frequency of sleep problems, and daytime sleepiness. Covariates included age, sex, ethnicity, body mass index, chronic health conditions, and household income.Results: Median (IQR) UFSG concentration was 0.67 (0.63) mg/L. Median (IQR) water fluoride concentration was 0.58 (0.27) mg/L among participants living in communities supplied with fluoridated municipal water and 0.01 (0.06) mg/L among those living in non-fluoridated communities. A 0.5 mg/L higher water fluoride level was associated with 34% higher relative risk of reporting sleeping less than the recommended duration for age [unweighted: RRR = 1.34, 95% CI: 1.03, 1.73; p = .026]; the relative risk was higher, though less precise, using survey-weighted data [RRR = 1.96, 95% CI: 0.99, 3.87; p = .05]. UFSG was not significantly associated with sleep duration. Water fluoride and UFSG concentration were not significantly associated with frequency of sleep problems or daytime sleepiness.Conclusions: Fluoride exposure may contribute to sleeping less than the recommended duration among older adolescents and adults in Canada. [ABSTRACT FROM AUTHOR]

The microbiological content of water is an ongoing concern in First Nations communities in Canada. Many communities lack water treatment plants and continue to be under drinking water advisories. However, lack of access to treatment plants is only a part of the problem as poor water distribution systems also contribute to the failure to provide safe drinking water. Here, we studied the microbial diversity and antibiotic resistome from water stored in cisterns from two First Nations communities in Manitoba, Canada. We found that the cistern water contained a high number of bacteria and showed the presence of diverse antimicrobial resistance genes. Interestingly, the bacterial diversity and antimicrobial resistance genes varied considerably from that of the untreated source water, indicating that the origin of contamination in the cistern water came from within the treatment plant or along the delivery route to the homes. Our study highlights the importance of proper maintenance of the water distribution system in addition to access to water treatment facilities to ensure a supply of safe water to First Nations communities in Canada.IMPORTANCEThe work described addresses a critical issue in First Nations communities in Canada-the microbiological content of water. Many of these communities lack access to water treatment plants and frequently experience drinking water advisories. This study focused on the microbial diversity and antibiotic resistome in water stored in cisterns within two First Nations communities in Manitoba, Canada. These findings reveal that cistern water, a common source of drinking water in these communities, contains a high number of bacteria and a wide range of antimicrobial resistance genes. This highlights a serious health risk as exposure to such water can lead to the spread of drug-resistant infections, posing a threat to the well-being of the residents., Competing Interests: The authors declare no conflict of interest.

Reservoirs are vital to meet the ever-increasing demands for freshwater in a warming climate. Dissolved organic matter (DOM) represents an important pool of carbon and can be a major concern in drinking water sources. However, insights into DOM dynamics in temperate, semi-arid reservoirs remain limited. Therefore, we investigated the variations in DOM properties in Lake Diefenbaker, a large reservoir on the Canadian Prairies, by analyzing eight years of DOM concentrations and composition through linear mixed effect modeling. Contrary to expectations, reservoir dissolved organic carbon (DOC) concentration showed no correlation with inflow from the South Saskatchewan River (p = 0.12), while dissolved organic nitrogen (DON) increased with decreasing inflow (p = 0.002). DOM optical indices (SUVA 254 and E 4 :E 6 ratio) and DOC:DON ratio revealed a pronounced influence of inflow on reservoir DOM composition (p < 0.001), i.e., allochthonous characteristics increased with increasing flow, and autochthonous characteristics increased with declining flow. Travel time corrected comparison of approximately the same water parcel along the reservoir length revealed that increasing water residence time in downstream regions led to a significant transformation in DOM composition, favoring autochthonous characteristics (mean SUVA 254 reduced by 0.52 L mg-C -1 m -1 , and the E 4 :E 6 and spectral slope ratio increased by 1.6 and 0.06, respectively). Autochthonous DOC inputs likely offset the allochthonous DOC losses, which resulted in a relatively stable DOC concentration throughout the reservoir (mean 3.7 mg L -1 ). Additionally, the effect of a large aquaculture operation on reservoir DOM properties was investigated, but no effect was detected. The results have significant implications for managing large river-reservoirs. Autochthonous DOM poses challenges to water processing, necessitating monitoring of DOM composition for reservoir drinking water quality. Insights on climate-induced changes in DOM properties will also assist with understanding changes to habitat conditions and contaminant transport., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Chloroform or trichloromethane is one of the trihalomethanes formed during disinfection of water with chlorine, and residues of chloroform can be detected in foods and food products due to the use of chlorinated drinking water and disinfecting food processing equipment with chlorine-based disinfectants. In this study, chloroform was detected in 37 (or 23%) of the 159 composite food samples from the 2014 Canadian Total Diet Study, but was not detected in cereals, fruits, fast foods, and most of the meat samples. Chloroform was detected in almost all 14 composite samples of dairy products, with the highest level (58 ng/g) observed in butter, followed by cream (26 ng/g), and cheese (12-21 ng/g). Chloroform was detected in tap water (23 and 29 ng/g) and most of the beverage samples, but concentrations were lower than those reported in other studies possibly due to evaporation during the preparation of the composite samples. Dietary exposures to chloroform are higher for younger age groups (0.51-1.41 µg/kg body weight/day) than for adults (0.25-0.42 µg/kg body weight/day). Drinking water contributed most to daily intakes for all age groups, accounting for between 62% and 86% of the total chloroform dietary intakes.

Background: Prenatal fluoride exposure can have adverse effects on children's development; however, associations with visual and cardiac autonomic nervous system functioning are unknown. We examined associations between prenatal fluoride exposure and visual acuity and heart rate variability (HRV) in 6-month-old infants., Methods: We used data from Canadian mother-infant pairs participating in the Maternal-Infant Research on Environmental Chemicals (MIREC) cohort. We estimated prenatal fluoride exposure using: i) fluoride concentration in drinking water (mg/L), ii) maternal urinary fluoride adjusted for specific gravity (MUF SG ; mg/L) and averaged across pregnancy, and iii) maternal fluoride intake (µg/kg/day) from consumption of water, tea, and coffee, adjusted for maternal body weight (kg). We used multivariable linear regression to examine associations between each measure of fluoride exposure and Teller Acuity Card visual acuity scores (n = 435) and assessed HRV (n = 400) using two measures: root mean square of successive differences (RMSSD) and the standard deviation of N-N intervals (SDNN) measured at 6-months of age., Results: Median (IQR) values for water fluoride, MUF SG , and daily fluoride intake were 0.20 (IQR: 0.13-0.56) mg/L; 0.44 (0.28-0.70) mg/L and 4.82 (2.58-10.83) µg/kg/day, respectively. After adjustment for confounding variables, water fluoride concentration was associated with poorer infant visual acuity (B = -1.51; 95 % CI: -2.14,-0.88) and HRV as indicated by lower RMSSD (B = -1.60; 95 % CI: -2.74,-0.46) but not SDNN. Maternal fluoride intake was also associated with poorer visual acuity (B = -0.82; 95 % CI: -1.35,-0.29) and lower RMSSD (B = -1.22; 95 % CI: -2.15,-0.30). No significant associations were observed between MUF SG and visual acuity or HRV., Conclusion: Fluoride in drinking water was associated with reduced visual acuity and alterations in cardiac autonomic function in infancy, adding to the growing body of evidence suggesting fluoride's developmental neurotoxicity., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: [Disclosure: Dr. Lanphear (co-author) served as a non-retained expert witness in the federal fluoride case to describe the results of the fluoride studies using the MIREC cohort (Food & Water Watch, et al. vs. U.S. Environmental Protection Agency, United States District Court for the Northern District of California at San Francisco. He received no payment for his service. All authors report no conflict of interest.]., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Copyright of Canadian Water Resources Journal / Revue Canadienne des Ressources Hydriques is the property of Taylor & Francis Ltd 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.)

Key Takeaways: Lead in drinking water is a top public health issue in the United States and Canada, with similarities and differences in how each country addresses it. Although lacking specifics in some aspects, Canada's new legislation for lead levels in drinking water means more stringent rules and more comprehensive methods for testing and treating. Strategies for sampling and testing are less prescriptive with this new guideline, allowing more flexibility in setting up a lead monitoring and service replacement program. The strategies used to replace and pay for lead service lines differ among various Canadian water utilities. [ABSTRACT FROM AUTHOR]

In May 2000, the drinking water system in Walkerton, Canada, became contaminated with deadly bacteria. The losses were enormous, but the outbreak could have been minimized by common water treatment practices, including the use of chlorine residual and turbidity monitors. [ABSTRACT FROM AUTHOR]

Background: After the discovery of fluoride as a caries-preventing agent in the mid-twentieth century, fluoridation of community water has become a widespread intervention, sometimes hailed as a mainstay of modern public health. However, this practice results in elevated fluoride intake and has become controversial for two reasons. First, topical fluoride application in the oral cavity appears to be a more direct and appropriate means of preventing caries. Second, systemic fluoride uptake is suspected of causing adverse effects, in particular neurotoxicity during early development. The latter is supported by experimental neurotoxicity findings and toxicokinetic evidence of fluoride passing into the brain.Method: An integrated literature review was conducted on fluoride exposure and intellectual disability, with a main focus on studies on children published subsequent to a meta-analysis from 2012.Results: Fourteen recent cross-sectional studies from endemic areas with naturally high fluoride concentrations in groundwater supported the previous findings of cognitive deficits in children with elevated fluoride exposures. Three recent prospective studies from Mexico and Canada with individual exposure data showed that early-life exposures were negatively associated with children's performance on cognitive tests. Neurotoxicity appeared to be dose-dependent, and tentative benchmark dose calculations suggest that safe exposures are likely to be below currently accepted or recommended fluoride concentrations in drinking water.Conclusion: The recent epidemiological results support the notion that elevated fluoride intake during early development can result in IQ deficits that may be considerable. Recognition of neurotoxic risks is necessary when determining the safety of fluoride-contaminated drinking water and fluoride uses for preventive dentistry purposes. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature 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.)

Freshwater ecosystems can experience harmful algal blooms, which negatively impact recreational uses, aesthetics, taste, and odor in drinking water. Cyanobacterial toxins can have dire repercussions on aquatic wildlife and human health, and the most ubiquitous worldwide are the hepatotoxic compounds known as microcystins. The factors that influence the occurrence and magnitude of cyanobacteria blooms and toxin production vary in space and time and remain poorly understood. It is within this context that we present a suite of statistical models, parameterized with Bayesian inference techniques, to link the retrospective analysis of important environmental factors with the probability of exceedance of threshold microcystin levels. Our modelling framework is applied to the Bay of Quinte, Lake Ontario, Canada; a system with a long history of eutrophication problems. Collectively, 16.1% of the samples of the system collected during the study period (2003–2016) exceeded the drinking water guideline of 1.5 μgL−1, while approximately 3% of recorded values exceeded the recommended recreational threshold of 20 μgL−1. Using a segmented regression model with a stochastic breakpoint of microcystin concentrations estimated at 0.54 μg L−1, we demonstrate that the environmental conditions associated with increased probability of exceedance of the drinking water standard are chlorophyll a concentration ≥7 μg L−1, water temperature ≥20 °C, ammonium concentration ≤40 μgL−1, total phosphorus concentration ≥25 μg L−1, and wind speed ≤37 km h−1. Considering the multitude of factors that can influence the ambient levels of toxins, our study argues that the adoption of probabilistic water quality criteria offers a pragmatic approach to accommodate the associated uncertainty by permitting a realistic frequency of violations. In this context, we present a framework to evaluate the confidence of compliance with probabilistic standards that stipulate less than 10% violations of microcystin threshold ambient levels. Image 1 • We developed a novel Bayesian method to guide Microcystin-LR risk assessment. • Our modelling framework is applied to the eutrophic Bay of Quinte in Lake Ontario. • Confidence of compliance with Microcystin standards is assessed with power analysis. • Phosphorus availability is the first condition for cyanobacteria dominance to occur. • Interspecific competition for bioavailable nitrogen leads to Microcystis dominance. [ABSTRACT FROM AUTHOR]

Prevention and control of water pollution for maintaining and restoring the wholesomeness of rivers are unavoidable. The current water quality approach of designated best use has some limitations such as it is non-integrative and inflexible with regard to the consideration of variables and does not provide a separate rating scale for a given designated use. We thus used water quality index approach proposed by the Canadian Council of Ministers of the Environment (CCME WQI) to evaluate and develop a separate rating system for drinking and irrigation purposes of rivers Beas, Satluj and their confluence water of the Indian Punjab using information collected over 4 years (2016 to 2019). River Beas exhibited better water quality compared to river Satluj for irrigation as well as for drinking. The overall drinking water quality index (DWQI) for Beas was marginal (45.5), whereas it was poor for Satluj (37.7) and confluence waters (40.1). The spatial variation in DWQI was greater for Satluj compared to Beas and confluence waters reflecting the effect of dumping of untreated industrial and domestic waste waters. Variables such as Total coliform (T. coli), dissolved oxygen (DO), turbidity and biological oxygen demand (BOD) contributed to the deterioration of DWQI. The irrigation water quality index (IWQI) was good for Beas (86), marginal for Satluj (60.1) and fair for confluence waters (71.2). Faecal coliform (F. coli), Kelly ratio (KR) and %Na contributed to the deterioration of IWQI. Calcium-magnesium-bicarbonate (Ca-Mg-HCO 3 ) was the dominant water type in Beas and confluence waters, whereas for Satluj, in addition to Ca-Mg-HCO 3 , sodium-potassium-chloride-sulphate and mixed water types were also prevalent. The river waters witnessed salinity hazard but did not pose sodicity hazard except at a few locations of Satluj. The study indicates the need to take location specific measures for improving river water quality for drinking as well as irrigation purposes. The current status of water quality calls for an urgent need to formulate stringent policy regulations to maintain the surface water quality., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Illegal gold mining activities have contributed to the release and mobilization of Hg and environmental degradation in many parts of the world. This study aims to determine the concentration of Hg in five provinces of the Amazon Region of Ecuador, in addition to assessing the risk to human health of exposed populations, applying deterministic and probabilistic methods. For this purpose, 147 water samples were collected in rivers and streams crossing and/or located near mining areas. As a result, 100% of the samples analyzed exceeded the maximum permissible limit (MPL) according to the water quality criteria for the preservation of aquatic life of the Ecuadorian regulations, while 7% of the samples exceeded the MPL for drinking water. On the other hand, considering the European Environmental Quality Standard (EQS) for surface water bodies, in our study, 100% of the samples exceed the maximum permissible limit (0.07 µg/L), and with respect to the Canadian water quality guidelines, 35% of the samples exceed the permissible limit (0.001 mg/l) for drinking water, and 100% of the samples exceed the limit for life in water bodies (0.0001 mg/l). The risk assessment revealed that the probability of developing adverse health effects from exposure to Hg is below the recommended limits according to the probabilistic assessment; this is in relation to the criterion of residential and recreational use of water resources. However, it was identified that the child population doubles the acceptable systemic risk level according to the results of the deterministic assessment in the residential scenario. This information can be used by decision-makers to implement strategies to reduce Hg contamination and exposure of the population in Ecuadorian Amazonian rivers., (© 2023. The Author(s).)

Copyright of Canadian Water Resources Journal / Revue Canadienne des Ressources Hydriques is the property of Taylor & Francis Ltd 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.)

A vegetated buffer, barrier, or filter strip is a parcel of land that is designated to separate land used for agriculture from valued aquatic or terrestrial habitats. It exists partly with the intent to diffuse runoff and to impeded sediment, nutrients, pesticides, and other constituents from reaching off-site surface waters. Mandatory buffer implementation is regulated at various levels of government in North America - from the federal to the state and provincial levels, and by some municipalities and counties. To better understand the degree and breadth of oversight, we undertook a comprehensive search and review of vegetative buffer regulations across North America. We determined the width of buffer required, under what habitat or field conditions, for which pesticides, and application type, amongst other attributes. For ground application, margins ranged from 1 m to upwards of greater than 4000 m depending on protection goals, with some being compound specific and others being generally applied to all registered pesticides/compounds. These buffers tended to be used most often to protect surface water, groundwater (e.g. drinking water wells), and nearby sensitive crops, but the required distances are generally not consistent between jurisdictions, regardless of the stated protection goals. We recommend that a thorough science-based review take place, with input from relevant stakeholders, to harmonize vegetated buffer size for effective surface water protection where ecological, climatic, and agricultural conditions are sufficiently similar in North America. • Width of vegetated buffers in agriculture in North America range from 1 to 4000 m. • Considerable variation in buffer width and structure exists across jurisdictions. • Programs to incentivize buffer construction are present in many jurisdictions. • Thought needs to be given to harmonize buffer regulations and incentives. [ABSTRACT FROM AUTHOR]

• Higher fluoride in drinking water is slow poison with irrecoverable consequences. • The paper discusses the natural factors behind occurrences of high fluorosis globally. • The Global Fluoride Belts are geographically connected and geologically similar with natural factors. • In situ process of fluoride removal techniques, their removal capacity, advantages and disadvantages are discussed. Fluorosis is an endemic disease that is now a global challenge. In this review paper we have classified and described the global fluoride belts (GFB) geologically and geographically connecting different countries. A proper map of the global fluoride belts showing the inland connections between each belt is presented. Several natural factors like the rock type, soil, tectonics, hydrogeology and climate of a terrain which are majorly responsible for engrafting higher fluoride in drinking water are described. A detailed uniform description of each belts with respect to geology, geochemistry are discussed. The minor factors like altitude, phosphate mining etc. on fluorosis are also discussed including countries like Canada, Norway etc. which are potentially affected by fluorosis. The correlation of different ions like Cl−, Ca2+, etc; pH, electrical conductivity, TDS etc are compared and reviewed in detailed with respect to different GFB. The genesis and sources of fluoride contamination are also supported by different isotopic evidences. In this article, the in situ methods involving natural minerals and materials which can adsorb fluoride effectively and are being used globally are exhaustively assessed. The methods which are highly sustainable with minimum waste generation and cost effective are also evaluated. [ABSTRACT FROM AUTHOR]

The City of White Rock purchased the water utility on October 30, 2015, from EPCOR Utilities Inc. The City of White Rock's water utility provides safe and clean drinking water to its residents. The drinking water is obtained from the Sunnyside Uplands Aquifer. To ensure water supplied is of the highest quality, the City collaborated with the RES'EAU-WaterNET, to conduct research to evaluate and identify technologies that are capable of providing a significant reduction of arsenic and manganese, to improve water quality. The City submitted a grant application to the Clean Water and Wastewater Fund (CWWF) for the construction of a water treatment plant to reduce arsenic and manganese in drinking water. The Government of Canada and the Province of British Columbia provided funding from the Clean Water and Wastewater Fund (CWWF) to the City of White Rock for the "Arsenic and Manganese Water Treatment Project. The City awarded a contract for the Design Build for a Water Treatment Plant to provide a major reduction in arsenic and manganese in drinking water. The Design Build project utilized the scientific findings from the research conducted. The construction of the plant started in March 2018, and the project is expected to be completed by March 2019. [ABSTRACT FROM AUTHOR]

Rational use of water is a major challenge for governments and global organizations, with easy and inexpensive interventions being sought by communities that are not supplied with drinking water. In this context, solar disinfection (SODIS) has shown great efficiency for water disinfection. To speed up the process and improve inactivation, we studied the effects of methylene blue (MB) as a photodynamic agent because of its ability to absorb visible light (red wavelength) and generate singlet oxygen as a reactive species, thereby inactivating bacteria and viruses present in water. In this study, samples of clean mineral water were artificially contaminated with Gram‐positive (Staphylococcus epidermidis or Deinococcus radiodurans) or with Gram‐negative strains (Escherichia coli or Salmonella typhimurium) and exposed to traditional SODIS or to MB‐SODIS. A lethal synergistic effect was observed when cultures were illuminated in the presence of MB. The obtained results indicate that bacterial inactivation can be achieved in a much shorter time when using MB associated with SODIS treatment. Therefore, this technique was able to provide safe water for consumption through the inactivation of microorganisms in general, including pathogens and some strains resistant to the traditional SODIS procedure, thus allowing its use in areas usually less exposed to sunlight. Data of global horizontal irradiation from World Databank/Solargis™ merged with the global population map. World regions with low solar irradiation (beige areas) represent regions with poor solar radiation (daily sum < 4.4 kWh m−2), while red areas represent areas with relevant solar radiation (daily sum ≥4.4 kWh m−2). The number of people living under poorly irradiated areas was estimated using the Population Explore™ software to be nearly 3 billion people. Considering that northern United States, Canada and Europe contain highly developed access to drinking water, it means that nearly half of this contingent, that is, ~ 1.5 billion people, would benefit from a process as MB‐SODIS worldwide. [ABSTRACT FROM AUTHOR]

Leaching of nitrate (NO3-) from animal waste or fertilisers at agricultural operations can result in NO3- contamination of groundwater, lakes, and streams. Understanding the sources and fate of nitrate in groundwater systems in glacial sediments, which underlie many agricultural operations, is critical for managing impacts of human food production on the environment. Elevated NO3- concentrations in groundwater can be naturally attenuated through mixing or denitrification. Here we use isotopic enrichment of the stable isotope values of NO3- to quantify the amount of denitrification in groundwater at two confined feeding operations overlying glacial sediments in Alberta, Canada. Uncertainty in δ15NNO3 and δ18ONO3 values of the NO3- source and denitrification enrichment factors are accounted for using a Monte Carlo approach. When denitrification could be quantified, we used these values to constrain a mixing model based on NO3- and Cl- concentrations. Using this novel approach we were able to reconstruct the initial NO3-N concentration and NO3-N/Cl- ratio at the point of entry to the groundwater system. Manure filtrate had total nitrogen (TN) of up to 1820 mg L -1 , which was predominantly organic N and NH3. Groundwater had up to 85 mg L -1 TN, which was predominantly NO3-. The addition of NO3- to the local groundwater system from temporary manure piles and pens equalled or exceeded NO3- additions from earthen manure storages at these sites. On-farm management of manure waste should therefore increasingly focus on limiting manure piles in direct contact with the soil and encourage storage in lined lagoons. Nitrate attenuation at both sites is attributed to a spatially variable combination of mixing and denitrification, but is dominated by denitrification. Where identified, denitrification reduced agriculturally derived NO3- concentrations by at least half and, in some wells, completely. Infiltration to groundwater systems in glacial sediments where NO3- can be naturally attenuated is likely preferable to off-farm export via runoff or drainage networks, especially if local groundwater is not used for potable water supply. [ABSTRACT FROM AUTHOR]

Abstract Triclosan is a broad-spectrum antimicrobial additive in consumer products that has been detected in human populations globally. The purpose of this study was to assess triclosan exposure among the Canadian population using urinary triclosan as a biomarker. Data from the Canadian Health Measures Survey (CHMS) that reported triclosan concentrations in 8195 urine samples collected from Cycle 2 (2009–2011) and Cycle 3 (2012−2013) were analyzed. Triclosan was detected in 69.8% of samples with the geometric mean concentrations of 16 μg/L (16 μg/g creatinine) for the total population, 13 μg/L (13 μg/g creatinine) for children (3–19 years of age), and 16 μg/L (17 μg/g creatinine) for adults. Triclosan concentrations significantly differed by age, income, education, and employment in healthcare occupations, but not by race/ethnicity, sex, region of residence, or drinking water preferences or sources. Linear regression models were used to identify factors associated with urinary triclosan concentration. Results showed that household income was associated with higher urinary triclosan concentrations in both children and adults. Employed in healthcare occupations were associated with higher urinary triclosan concentrations in adults. Triclosan exposure at the 99th percentile was below the Biomonitoring Equivalents based on reference dose, suggesting that health risks to the Canadian population from triclosan exposure were low. Highlights • Triclosan concentrations in 8195 urine samples collected from Canadians are reported. • Triclosan concentrations differed by age, income, education, and employment in healthcare occupations. • Health risks to the Canadian population from triclosan exposure were low. [ABSTRACT FROM AUTHOR]

• Polarity switching for simultaneous mass analysis in positive and negative ESI. • Quantitation of organic UV filters in chlorinated waters. • SPE allows for preconcentration of low level analytes in swimming pools. Ultraviolet filters (UVFs) absorb UV light and are comprised of numerous classes of compounds including inorganic and organic. They have been used for decades in protecting humans from skin damage and cancer. Recent studies have shown that UVFs are found in many phases of abiotic and biotic systems with their physical-chemical characteristics determining environmental fate and potential biological impacts such as bioaccumulation. This study developed a unified method to quantify eight UVFs (avobenzone, dioxybenzone, homosalate, octinoxate, octisalate, octocrylene, oxybenzone, and sulisobenzone) by solid phase extraction and ultra-high performance liquid chromatography-tandem mass spectrometry using polarity switching. The validated method resulted in accuracies ranging from 75 to 112%, MLD/MLQs of 0.00015/ 0.00049 to 0.0020/ 0.0067 ng mL−1, and precisions of 1.8 to 22.6% (intraday) and 1.3 to 17.2% (interday). The method was applied to chlorinated outdoor pool waters in the City of Winnipeg, Manitoba, Canada. This method could be adapted for a variety of chlorinated and unchlorinated waters such as drinking water, wastewater, and surface waters. [ABSTRACT FROM AUTHOR]

In Canada, over 400,000 enteric diseases related to drinking water occur each year, highlighting the importance of understanding sources of Canadians' drinking and recreational water exposures. To address this need, a population-based telephone survey of 10,942 Canadians was conducted between 2014 and 2015, assessing Canadian's drinking water sources and recreational water exposures using a seven-day recall method. Results were analyzed by province/territory, season, age group, gender, income, education, and urban/rural status. Store-bought bottled water was reported by nearly 20% of survey respondents as their primary drinking water source, while approximately 11% of respondents reported private well. The proportion of private well users was significantly greater than the national average in the Maritime Provinces where approximately 40-56% of respondents reported this as their primary drinking water source. As expected, Canadians' recreational water activities and exposures (e.g., swimming, pool, lake, and waterpark) peaked during summer and were most commonly reported among children aged 0-9 years. Waterborne disease in Canada requires a multi-faceted public health approach. Canadian baseline data on water exposures can inform policy and public health strategies (e.g., recreational water guidelines, private well water testing recommendations) and support research and risk assessment related to mitigating waterborne illness [ABSTRACT FROM AUTHOR]

Concerns regarding the safety and aesthetic qualities of one's municipal drinking water supply are important factors influencing drinking water perceptions and consumption patterns (i.e. sources used and daily volume of consumption). In northern Canada, Inuit communities face challenges with drinking water quality, and many Inuit have reported concerns regarding the safety of their drinking water. The objectives of this research were to describe perceptions of municipal tap water, examine use of water sources and changes following the installation of a potable water dispensing unit (PWDU) in 2014, and identify factors associated with water consumption in the Inuit community of Rigolet. This study used data from three cross-sectional census surveys conducted between 2012 and 2014. Principal component analysis (PCA) was used to aggregate data from multiple variables related to perceptions of water, and logistic regressions were used to identify variables associated with water consumption patterns. Three quarters of residents reported using the PWDU after its installation, with concomitant declines reported in consumption of bottled, tap, and brook water. Negative perceptions of tap water were associated with lower odds of consuming tap water (OR PCAcomponent1 = 0.73, 95% CI 0.56–0.94; OR PCAcomponent2 = 0.67, 95% CI 0.49–0.93); women had higher odds of drinking purchased water compared to men (OR = 1.90, 95% CI 1.11–3.26). The median amount of water consumed per day was 1 L. Using brook water (OR = 2.60, 95% CI 1.22–5.56) and living in a household where no one had full-time employment (OR = 2.94, 95% CI 1.35–6.39) were associated with consuming > 2 L of water per day. Results of this study may inform drinking water interventions, risk assessments, and public health messaging in Rigolet and other Indigenous communities. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Water Resources Journal / Revue Canadienne des Ressources Hydriques is the property of Taylor & Francis Ltd 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.)

Background:-Community water fluoridation is the more cost effective than other forms of fluoride treatment and it gives small amount of fluoride to children and adults over time which prevents cavities and improves oral health. According to US Department of Health And Human Services the optimum level of fluoride should be 0.7 milligrams per liter. Material and Method- Tap water from different major cities of both the countries including CanadaandIndia has collected to estimate the fluoride content in them. Result:Tap water of different cities of India state Punjab has unsatisfactory content of fluoride.All samples of India have less than optimum level of fluoride content whereas on the other side tap water of Canada has much more fluoride content as compared to India but four cities of Ontario state of Canada named Brampton,Hamilton,Mississauga,Toronto has less fluoride content as compared to optimum content of fluoride which is 0.7 milligrams per liter.Only Waterloo city of Ontario state of Canada has optimum level of fluoride which is 0.7milligram per liter.Conclusion: water fluoridation plays a very important role in theprevention of dental caries.There should be opimum of 0.7 mg per liter of water. If optimum content of fluoride less than 0.7mg then it causes dental caries. [ABSTRACT FROM AUTHOR]

SourceWater Protection (SWP) is the process of protecting a drinking water source through land use planning policies and land management activities. The risk of source water contamination is a human health concern even in developed countries such as Canada. Much of the existing SWP literature in the more developed world is centred on small and rural water systems with a focus on capacity needs to support SWP activities and planning. These capacity needs tend to centre on five key elements: political, financial, human, technical and legal. While these contributions have added value to the water resource planning literature in rural areas, there remains a noticeable gap in the literature with respect to SWP activities in metropolitan areas. The purpose of this paper is twofold: first, to report the kinds of source water threats facing metropolitan water systems in Canada; and, second, to explore the utility of the capacity literature with respect to SWP planning in metropolitan Canada. [ABSTRACT FROM AUTHOR]

Source water protection (SWP) is increasingly seen as effective in reducing the incidence and extent of drinking water crises, yet its facilitation requires certain measures. Canada has one of the most decentralized water governance systems in the world. We sought to understand the experience and impacts of drinking water crises at community and government levels in a decentralized context: the Canadian province of Newfoundland and Labrador through cross-case analysis. We selected our three study communities through a database of media reports in 2014 followed by invitations to community leaders. We used descriptive and qualitative methods, specifically structured interview schedules with both closed- and open-ended questions, and interviewed four community leaders and three provincial government officials. We used NVivo in data analysis, especially in the identification of themes. While government officials defined water crises largely in terms of SWP, this was not the same for communities, whose concern was mainly water access, specifically water shortages. Thus, while the prioritizing of SWP can be useful, the current focus on SWP has the potential to overlook aspects of water security, particularly in some rural and Indigenous communities in Canada. If we envision water security as a ladder representing a hierarchy of needs, some communities are too far down on the ladder to operationalize SWP because their water problems are more extreme. [ABSTRACT FROM AUTHOR]

Background: Drinking water insecurity and related health outcomes often disproportionately impact Indigenous communities internationally. Understanding media coverage of these water-related issues can provide insight into the ways in which public perceptions are shaped, with potential implications for decision-making and action. This study aimed to examine the extent, range, and nature of newspaper coverage of drinking water security in Canadian Indigenous communities.Methods: Using ProQuest database, we systematically searched for and screened newspaper articles published from 2000 to 2015 from Canadian newspapers: Windspeaker, Toronto Star, The Globe and Mail, and National Post. We conducted descriptive quantitative analysis and thematic qualitative analysis on relevant articles to characterize framing and trends in coverage.Results: A total of 1382 articles were returned in the search, of which 256 articles were identified as relevant. There was limited coverage of water challenges for Canadian Indigenous communities, especially for Métis (5%) and Inuit (3%) communities. Most stories focused on government responses to water-related issues, and less often covered preventative measures such as source water protection. Overall, Indigenous peoples were quoted the most often. Double-standards of water quality between Indigenous and non-Indigenous communities, along with conflict and cooperation efforts between stakeholders were emphasized in many articles.Conclusion: Limited media coverage could undermine public and stakeholder interest in addressing water-related issues faced by many Canadian Indigenous communities. [ABSTRACT FROM AUTHOR]

Approximately 20% of the 600 First Nations reserves across Canada are under a drinking water advisory, often due to unacceptable levels of bacteria. In this study, we detected fecal bacteria at an alarmingly high frequency in drinking water sources in a fly-in First Nations community, most notably in buckets/drums of homes without running water where Escherichia coli levels ranged from 20 to 62,000 CFU/100 mL. The water leaving the water treatment plant was free of E. coli and its free residual chlorine concentration (0.67 mg/L) was within the range typically observed for treated water in Canada. Water samples from taps in homes served by cisterns, and those sampled from the water truck and community standpipe, always showed unacceptable levels of E. coli (1 to 2100 CFU/100 mL) and free residual chlorine concentrations below the 0.2 mg/L required to prevent bacterial regrowth. Samples from taps in homes served by piped water had lower levels of E. coli (0 to 2 CFU/100 mL). DNA- and RNA-based 16S rRNA Illumina sequencing demonstrated that piped and cisterns water distribution systems showed an abundance of viable cells of Alphaproteobacteria indicative of biofilm formation in pipes and cisterns. The alpha diversity, based on observed OTUs and three other indices, was lowest in water truck samples that supplied water to the cistern and the low free residual chlorine concentration (0.07 mg/L) and predominance of Betaproteobacteria (63% of viable cells) that were immediately detected after the truck had filled up at the water treatment plant was indicative of contamination by particulate matter. Given these findings, First Nation residents living without running water and relying on inadequate water distribution systems are at higher risk of contracting water-born illnesses. We urge all governments in Canada to expand their investments in supporting and sustaining water as a human right in Canada's First Nations communities. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are transferred from mother to infants through breastfeeding, a time when children may be particularly vulnerable to PFAS-mediated adverse health effects. Infants can also be exposed to PFAS from infant formula consumption. Our recent literature-based scoping of breast milk levels reported that four PFAS often exceeded the United States Agency for Toxic Substances and Disease Registry (ATSDR) children's drinking water screening levels in both the general population and highly impacted communities in the U.S. and Canada. This work presents a comparison of global breast milk and infant formula PFAS measurements with the only reported health-based drinking water screening values specific to children. We focused on four PFAS for which ATSDR has developed children's drinking water screening values: PFOA (perfluorooctanoic acid), PFOS (perfluorooctanesulfonic acid), PFHxS (perfluorohexanesulfonic acid), and PFNA (perfluorononanoic acid). Published literature on PFAS levels in breast milk and infant formula were identified via PubMed searches. Data were compared to children's drinking water screening values. Breast milk concentrations of PFOA and PFOS often exceed children's drinking water screening values, regardless of geographic location. The limited information on infant formula suggests its use does not necessarily result in lower PFAS exposures, especially for formulas reconstituted with drinking water containing PFAS. Unfortunately, individuals generally cannot know whether their infant's exposures exceed children's drinking water screening values. Thus, it is essential that pregnant and lactating women and others, especially those having lived in PFAS-contaminated communities, have data required to make informed decisions on infant nutrition. An international monitoring effort and access to affordable testing are needed for breast milk, drinking water and infant formula to fully understand infant PFAS exposures. Currently, our understanding of demonstrable methods for reducing exposures to emerging PFAS is limited, making this research and the communications surrounding it even more important. [Display omitted] [ABSTRACT FROM AUTHOR]

Introduction: Chronic exposure to arsenic through drinking water has been linked to several cancers. The metabolism of arsenic is thought to play a key role in arsenic-related carcinogenesis as metabolites of varying toxicity are produced and either stored in or excreted from the body. Atlantic Canada has the highest age-standardized incidence rates of all cancers in the country. This may be due to its high levels of environmental arsenic and the prevalence of unregulated private wells for water consumption. Here, we aimed to characterize the profiles of arsenic species and metallome in the toenails of four cancer groups, compare them to healthy participants ( N  = 338), and assess potential associations between the profiles with cancer prevalence., Methods: This study employed a case-control design. Toenail samples and questionnaire data from cases (breast, cervical, prostate, and skin cancers) and controls were sourced from the Atlantic Partnership for Tomorrow's Health (PATH) cohort study. The levels of arsenic species were measured using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) paired with High Performance Liquid Chromatography (HPLC) and total concentrations of metallome (23 metals) were determined by ICP-MS separately. Multivariate analyses were conducted to compare cases with controls within each cancer group., Results: Arsenic speciation profiles varied by cancer type and were significantly different between cases and controls in the breast ( p  = 0.0330), cervical ( p  = 0.0228), and skin ( p  = 0.0228) cancer groups. In addition, the profiles of metallome (nine metals) were significantly differentiated in the prostate ( p  = 0.0244) and skin ( p  = 0.0321) cancer groups, with higher zinc concentrations among cases compared to controls., Conclusion: History of cancer diagnosis was associated with specific profiles of arsenic species and metallome. Our results indicate that arsenic methylation and zinc levels, as measured in toenails, may be an important biomarker for cancer prevalence. Further research is needed to use toenails as a prognostic measure of arsenic-and other metal-induced cancer., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Hood, Sweeney, Ilie, Keltie and Kim.)