No description available.

Tap water supply is an essential resource for human societies. However with increasing water use and global warming, this resource needs to be monitored and managed sustainably. Here we use stable isotopes to identify potential issues associated with tap water resources in Canada. We analyze isotopes of 576 tap water samples collected from across Canada and classified them based on their supply sources including groundwater (TapGroundwater), river (TapRiver) and lake (TapLake). We found, isotopic values in tap water correlate strongly with those predicted in local precipitation across Canada, suggesting precipitation is the parent source of tap water. However, this correlation is stronger for TapGroundwater and TapRiver than TapLake. To explain this difference, we constructed a series of water balance models to predict isotopic values of surface water across Canada validated against Canadian rivers isotopes data. We then compared the tap water isotopic values to those predicted in local surface water, which improved the predictability of TapRiver and TapLake but not TapGroundwater. We suggest, TapGroundwater usually reflects isotopic values of annually averaged precipitation whereas TapRiver and TapLake reflect post-precipitation processes. We used the residuals between our observed and predicted isotope data to assess regional sources and processes influencing tap water isotopes across Canada. Regionally, snow/glacier melt from the Rockies contributes to groundwater recharge across Western Canada as well as to some rivers and lakes in Alberta and British Columbia. Also, tap water are highly evaporated across Western Canada irrespective of their sources. Across the Great Lakes and East Coast regions, lakes undergo high evaporative losses. Also, many localities in the East Coast pump and store groundwater in small lakes or ponds exposing them to evaporation. Our data and models provide a baseline for isotope monitoring of tap water resources and isotope forensic studies across Canada.

In May of 2006, the Hrubec group suddenly began to observe neural tube defects (NTDs) in embryos of untreated control mice. Unintentional exposure to a teratogenic agent in tap water was identified as the cause. We aimed to identify the contaminant, but first we demonstrated that the NTDs were pathological being present on both gestational day 9 and 10. We also found that a second species, rats, developed NTDs when exposed to tap waters. Disinfection by-products (DBPs) arise when natural organic matter in municipal water sources reacts with disinfectants used in the water treatment process. Purge and trap gas chromatography-mass spectrometry (PT GC-MS) and animal exposure studies were used to determine if the teratogenic contaminant was a DBP. Since the distribution pattern of DBPs did not match the distribution pattern of NTDs, we concluded that a DBP was not likely to be responsible for the observed malformations. Pharmaceuticals and personal care products have emerged as ubiquitous contaminants of ground and surface waters, and have been detected in drinking water. In order to analyze for these compounds, we submitted different water samples to a commercial water analysis lab (AXYS Analytical Services, Sidney, BC, Canada). Several pharmaceuticals were identified in a number of samples, including a known teratogenic drug used to treat mood disorders and seizures: carbamazepine. Further analysis for carbamazepine was conducted in-house. Carbamazepine was found in several ground, surface, and tap waters, at various concentrations. To establish whether or not carbamazepine was responsible for NTDs in our mice, we conducted 2 dosing studies. Carbamazepine was provided to mice at concentrations detected in tap water, as well as approximately 2 x and 1000 x that concentration. Both studies found no significant differences in NTD rates among the dose groups. As no dose effect was observed, we concluded that CBZ was not directly responsible for the malformations. The identity of the teratogenic contaminant is not known at this time, but is unlikely to be a DBP or low concentrations of the pharmaceutical carbamazepine. / Master of Science

The aim of this thesis is to obtain a basic knowledge of the factors that affect corrosion of aluminium in tap water for different kinds of applications like water pipes for tap water, solar systems, HVAC&R-applications (like fan coil units on chillers) and heat sinks for electronic or industrial applications. Open systems are used in some applications and closed systems in others. There is a clear difference in the corrosion behaviour of these two systems. The main reasons for this difference are that the content of oxygen differs between the two systems and also that inhibitors can be used in closed systems to hinder corrosion. In this thesis focus will be on corrosion in open systems. The corrosion properties in tap water for different alloys of aluminium and different surface treatments have been examined. The influences on corrosion of the oxygen content in water and the iron content in aluminium alloys have been investigated. The corrosion properties of an aluminium alloy in deionised water have also been examined.

No description available.

No description available.

In the first chapter, I consider the institutional structures as well as the doctrines typically encountered in the surface water sector. To investigate the sources and methods of government support in the water sector, I categorize different sorts of government support according to the location of water along the water cycle. I conclude the section with examples of observed water markets. In the second chapter, I consider the problem of water usage, developing a model to analyze the optimal pricing of water within a second-best economy. As a water supplier, the local government may price discriminate across consumers and farmers. I introduce the second-best pricing scheme, derive conditions for the marginal-cost pricing and inverse-elasticity rules, and analyze when the government optimally deviates from these two pricing schemes. In the third chapter, I provide an analysis of the data I collected from Turkey. First, I examine the data on reservoir flows, including service share and fixed costs of the reservoirs. Then, I provide details about the relationship between the quantity and price of irrigation and of tap water. Finally, in the fourth chapter, I apply the theoretical framework to the data from Turkey. In Turkey, the current water-pricing policy is dictated by the sole objective of breaking-even in each period. This results in large withdrawals, which is not sustainable in the long-run, hence not optimal. I analyze the dynamic optimal water resource management problem of a benevolent government. I compare the implications of the current and the optimal pricing policies.

Previous studies have shown that low-income Latinos frequently drink bottled water instead of tap water and might be at increased risk for dental caries from unfluoridated bottled water. The goals of this study were to: 1) determine if a difference exists between grab samples of municipal tap water and bottled water used by families in Nogales, Arizona in chemical and microbial contaminants; 2) understand the risk perceptions these low-income families have about both their publically supplied tap water, bottled/vended water; and 3) examine whether families have adequate fluoride levels in their drinking water for optimal dental health. Tap and bottled water samples were collected from thirty of these households for analysis of drinking-water contaminants regulated by the U.S. Environmental Protection Agency (USEPA). Bottled water included small (0.5 L) and large (3.8 L), individually sealed water bottles as well as water vended into reusable containers from self-service vending machines or from water stores. Some of the large bottles were purchased sealed, but had been previously opened and partially consumed by study participants. In addition to the 30 households mentioned above, an additional sixty low-income Latino households, who primarily drink bottled water, were also recruited for this study to complete a questionnaire on risk perceptions related to drinking water consumption, water storage practices, and fluoride supplementation. There were no significant differences in the concentration of chemical contaminants between tap, bottled and vended water, and none of the chemical concentrations exceeded USEPA regulations. Escherichia coli (E. coli) was confirmed in 3% (1/30) of tap, 0% (0/8) of sealed bottled, 40% (2/5) of previously opened bottled, and 35% (6/17) of vended water samples. One of the 3 samples collected directly from a vending machine had an E. coli concentration of 0.33 CFU/100 mL. None of the 10 samples collected directly from sealed bottles purchased directly from the store had any E. coli detected. While no significant differences were observed in the chemical quality of water samples, results suggest that secondary contamination in the home contributes to higher levels of E.coli in water from partially consumed larger water bottles or water stored in reusable containers. Families who reported cleaning large reusable water containers with soap or hot water had significantly lower E.coli (p=0.003) in their drinking water than those who rinsed with only water. Respondents viewed bottled water to be significantly safer to consume than tap water (p<0.001). On a Likert scale from 1 (low risk) to 5 (high risk), "drinking tap water in Nogales, Arizona" received an average score of 4.7, which was significantly higher than the average perceived risk of smoking (µ= 3.5, p<0.001) or of "drinking tap water in San Francisco, California" (µ= 3.4, p<0.001), and as risky as "drinking and driving" (µ= 4.8, p=1.00) and "drinking tap water in Nogales, Sonora, Mexico" (µ= 4.8, p=1.00). Additionally, 98% (88/90) of respondents feared that drinking local tap water could result in illness. The majority of respondents (79%, 71/90) did not drink their tap water because of fear of contamination and would drink their tap water if they knew it was safe, regardless of the taste (73%, 66/90).Fluoride was detected in 53% (16/30) of tap-water samples and only in one bottled-water sample. However, only 27% (8/30) of tap-water samples had fluoride levels within the recommended range (0.7-1.2 mg/L) by the American Dental Association for optimally fluoridated water. From multiple logistic regression, children in a household were less likely to have cavities if their parents reported using fluoridated mouthwash (p<0.001) or visited the dentist yearly (p<0.001). None of the participants reported discussing the type of water they drank or fluoride supplementation with any healthcare providers. Results suggest that secondary contamination in the home is contributing to significantly higher levels of bacteria in vended water stored in reusable containers. In addition, fear of illness from contamination of tap water is an important contributing factor to increased use of bottled water. Interventions could be developed to educate families about how to keep their reusable water containers clean, reduce perceived risks associated with tap-water consumption, and emphasize the importance of fluoride supplementation if families continue drinking bottled water.

Perfluoroalkyl substances (PFASs) are man-made chemicals. Their unique properties make them beneficial for a wide range of industrial and consumer product applications, such as in aqueous film forming foam (AFFF), durable water repellent clothing, hydraulic oils and food packaging materials. Perfluoroalkyl acids (PFAAs), a class of PFASs, are highly persistent in the environment, and long chain PFAAs are bioaccumulative and toxic. International regulation and voluntary actions by the industry have been implemented and led to a recent reduction of primary emissions of PFAAs to the environment. However, point sources such as AFFF training sites as well as diffuse sources continue to contaminate water bodies, soil and biota. Reducing environmental pollution with PFAAs has therefore become a regulatory priority. Designing successful measures to reduce the PFAA contamination requires an understanding of the sources, transport and fate of PFAAs in the environment. Four scientific publications are included in this PhD thesis, which aimed at increasing the holistic understanding of the fate of PFAAs in aquatic systems. This was achieved by chemical trace analysis combined with mass balance modeling. The following topics were covered: Dispersion and fate of PFAAs from an AFFF-impacted site (Paper I), recirculation of PFAAs in the aquatic environment with focus on waste water treatment plants (WWTPs, Paper II), mass balance of PFAAs in the Baltic Sea (Paper III) and transport and fate of PFAAs in two pristine boreal stream catchments (Paper IV). Results from Paper I showed that AFFF-impacted sites at a former military airfield, which was abandoned for more than 30 years, continue to be point sources of PFAAs to recipients. The sum of PFAAs in the ground water and surface waters ranged from 740 to 51000 ng L-1 and &lt;0.5 to 79 ng L-1, respectively. PFOS in muscle tissue of European perch from a nearby lake ranged from 77 to 370 ng g-1 wet weight, representing among the highest values reported worldwide for fish muscle. In Paper II the relative importance of environmental recirculation of PFAAs versus new releases from the technosphere was investigated for PFAAs in WWTP influents. It was shown that tap water can be an important source of PFAAs to WWTPs in areas with elevated environmental levels. This needs to be taken into account when calculating emissions via WWTP effluents. PFAA mass balances over the WWTPs suggested that PFHxA and PFOA were formed from precursor compounds within the plants. Assembled PFAA mass balances for the Baltic Sea (Paper III) showed that river inflow and atmospheric deposition were the dominant input pathways, while wastewater treatment plant (WWTP) effluents discharging directly into the Baltic Sea made a minor contribution. The inputs of PFAAs were estimated to be higher than the outputs, suggesting a current increase of the PFAA inventory in the Baltic Sea. Also the mass balance study of PFAAs in two remote stream catchments presented in Paper IV revealed that inputs dominated over outputs for both catchments, indicating that a considerable portion of the PFAAs deposited from the atmosphere is retained in soil or in deep ground water and may be released to surface and marine water environments in the future / Perfluoralkilne tvari (PFASs) su umjetne kemikalije. Zbog svojih jedinstvenih svojstava široko su primjenjive u industriji i izradi proizvoda krajnje potrošnje kao što su pjena za gašenje požara (AFFF), vodootporna odjeća, hidraulična ulja i pakiranja za hranu. Perfluoralkilna kiselina (PFAAs) iz skupine perfluoralkilnih tvari iznimno je dugotrajna u okolišu, a dugolančane PFAAs su bioakumulativne i otrovne. Poduzeta međunarodna regulativa i dobrovoljne akcije vodile su nedavno smanjenoj primarnoj emisiji PFAAs u okoliš. Unatoč tome, primarni izvori, kao što su mjesta na kojima se provode treninzi za gašenje požara i difuzni izvori i dalje zagađuju vode, tlo i biotu. Zbog toga, smanjenje onečišćenja okoliša izazvanog PFAAs predstavlja regulatorni prioritet. Stvaranje uspješnih mjera kojima bi se smanjilo onečišćenje izazvano PFAAs zahtjeva razumijevanje izvora, prijenosa i sudbine tih tvari u okolišu. U ovaj doktorat uključena su četiri znanstvena članka kojima je cilj povećati sveukupno razumijevanje sudbine PFAAs u vodenim sustavima. To je postignuto kemijskom analizom elemenata u tragovima u kombinaciji s modeliranjem masene ravnoteže. Obrađene su sljedeće teme: Širenje i sudbina PFAAs na područjima zahvaćenim AFFF (Članak I), ponovna cirkulacija PFAAs u vodenom okolišu s naglaskom na postrojenja za pročišćavanje otpadnih voda (Članak II), masena ravnoteža PFAAs u Baltičkom moru (Članak III) te prijenos i sudbina PFAAs u dva udaljena sjeverna vodena toka (Članak IV).   Rezultati iz Članka I pokazali su da su područja zahvaćena AFFF na bivšem vojnom aerodromu napuštenom prije 30 godina i dalje je glavni izvor PFAA zagadenja okolisa. Zbroj PFAAs u podzemnim i površinskim vodama kreće se u rasponu od 740 do 51000 ng L-1 i &lt;0.5 do 79 ng L-1. PFOS u mišićnom tkivu grgeča iz obližnjeg jezera kreće se od 77 do 370 ng g-1 mokre težine, predstavljajući jednu od najviših vrijednosti u svijetu za riblje mišiće. Članak II istražuje relativnu važnost ponovne cirkulacije PFAAs imajući na umu novu emisiju PFAAs iz tehnosfere u postrojenjima za pročišćavanje otpadnih voda. Cirkulacija/kruženje u okolišu može se pojaviti kada PFAAs iz sustava pitke voda (rijeka, bunara i jezera) odlaze u otpadne vode. Prikazano je kako voda iz slavine može biti važan izvor PFAAs sustavima za pročišćavanje otpadnih voda u područjima s povišenim razinama zaštite okoliša. To se treba uzeti u obzir pri računanju emisije putem strojeva koji se koriste za pročišćenje otpadnih voda. Masena ravnoteža PFAA u postrojenjima za pročišćavanje otpadnih voda upućuje na to da su PFHxA i PFOA stvoreni kao prethodni spojevi unutar postrojenja. Prikupljene masene ravnoteže PFAA za Baltičko more (Članak III) pokazale su da su pritoke rijeka i atmosfersko taloženje dominantni ulazni putovi, dok postrojenja za pročišćenje otpadnih voda pridonose tek u manjoj mjeri. Ulaz PFAAs je procijenjen višim od izlaza, što objašnjava trenutno povećanje sadržaja PFAA u Baltičkom moru. Masena ravnoteža PFAAs u dva udaljena riječna toka predstavljena u Članku IV otkriva da ulaz dominira nad izlazom za oba riječna toka, što upućuje na značajan udio PFAAs koji je iz atmosfere zadržan u tlu ili podzemnim vodama te može biti ispušten u područja površinskih voda i mora. / Perfluorerade alkylsyror (PFAA) är kemikalier som är producerade av människan. Deras unika egenskaper gör att de kan användas i många olika industriella applikationer. PFAAs används i brandsläckningsskum, vattenavvisande kläder, hydrauliska oljor och matförpackningar. PFAAs har visat sig vara persistenta i miljön, och långkedjiga PFAA-homologer har visat sig vara bioackumulerbara samt ha en toxisk verkan. Reglering på internationell nivå tillsammans med initiativ från industrin har lett till minskning av direkta utsläpp. Punktkällor som brandövningsplatser samt andra diffusa källor fortsätter att förorena omgivande vattendrag, jordlager och fauna. Den utbredda föroreningen av PFAAs har därför blivit prioriterad för reglering. För att förstå utsläppen av PFAAs i miljön, hur de transporteras samt deras öde i miljön, är det viktigt att utföra studier som belyser dessa områden.   Denna doktorsavhandling inkluderar fyra vetenskapliga publikationer. Syftet med de underliggande studierna var att öka den holistiska förståelsen av PFAAs rörelse i akvatiska system. Studierna gjordes genom att kombinera kemiska analysmetoder med modellering. Följande  studier genomfördes; Transport och spridning av PFAAs från en brandövningsplats (Paper I), recyklering av PFAAs i den akvatiska miljön med fokus på vattenreningsverk (Paper II), massbalans av PFAAs i Östersjön (Paper III), transport och öde av PFAAs i två pristina vattendrag (Paper IV).   Resultat från (Paper I) visade att brandövningsplatser vid en flygplats som inte har varit i bruk i mer än 30 år, fortfarande är punktkällor av PFAAs till omgivande vattendrag. Summan av PFAAs koncentrationer i grundvattnet och ytvattnet sträckte sig från 740 till 51000 ng L-1 och &lt;0.5 till 79 ng L-1 i respektive vattendrag. Koncentrationen av PFOS i muskelvävnad från  aborre i en av sjöarna var 77 till 370 ng g-1 våtvikt. Dessa värden representerar några av de högsta uppmätta koncentrationerna i världen. I Paper II testades betydelsen av PFAAs från recirkulering i miljön i jämförelse med nya utsläpp från teknosfären. Recirkulering av PFAAs i miljön kan förekomma då PFAAs i inkommande vatten till reningsverk kommer från dricksvatten. Denna studie visar att dricksvatten kan vara en påtaglig källa av PFAAs till vattenreningsverk i områden med förhöjda halter av PFAAs i miljön. Detta måste tas hänsyn till när man beräknar emissioner med utgående vatten från vattenreningsverk. Massbalanser av PFAAs i reningsverken visar att PFHxA och PFOA bildades av prekursorämnen i vattenreningsverken. I Paper III beräknades massbalanserna av PFAAs i Östersjön, beräkningarna visar att floder och atmosfärisk nedebörd var de viktigaste källorna medan utsläppen från vattenreningsverk var markant lägre. Importen av PFAAs estimerades vara högre än exporten, varför vi tror att PFAAs mängden I Östersjön kommer att öka över tid. Vidare gjordes en mass balans av PFAAs i två avlägsna avrinningsområden (Paper IV). Resultaten visar att importen av PFAAs dominerar över exporten från båda avrinningsområdena. Detta indikerar att en stor del av PFAAs som kommer ner via nederbörd kommer att ansamlas i jorden eller i grundvattnet. Dessa PFAAs kan vid senare tillfälle komma att släppas ut till floder som rinner ut i marina vatten. / <p>At the time of the doctoral defense, the following paper was unpublished and had a status as follows: Paper 2: Manuscript.</p><p> </p>

This thesis paper explores how various actors gathered around bottled water when a ban was put into place in Concord, Massachusetts. The objective has been to answer the following questions: How does an apolitical commodity become a political one? Specifically, how does bottled water move from being an apolitical commodity to become a highly political one? What does this mean for environmental politics? I situate my theoretical approach within Martha Kaplan’s research with fountains and coolers. I use Bruno Latour to show in which ways this ban became a matter of concern, as well as how the ban and the plastic bottle are actors. I conducted fieldwork in Concord and I interviewed participants. My findings reveal that the ban brought meanings to the surface and challenged them or supported them in various ways. The discussions turned from the impact of bottled water on our environment to the political impact of bottled water companies and large corporations on local Concord issues.