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Sodium bicarbonated mineral water decreases postprandial lipaemia in postmenopausal women compared to a low mineral water.

The role of bicarbonated mineral waters on lipid metabolism and lipoprotein concentrations in man has scarcely been investigated. The present study aimed to investigate whether drinking sodium bicarbonated mineral water affects postprandial cholesterol and triacylglycerol metabolism in postmenopausal women. In a three-way, randomised, crossover study, eighteen healthy postmenopausal women consumed two sodium bicarbonated mineral waters (bicarbonated mineral water 1 and bicarbonated mineral water 2) and a low mineral water (500 ml of each) with a standard fat-rich meal (4552 kJ; 75.3 g fat). The bicarbonated waters were rich in sodium and bicarbonate and bicarbonated mineral water 1 contained 5.7 times more fluoride than bicarbonated mineral water 2. Fasting blood samples and postprandial blood samples were taken at 30, 60, 120, 240, 360 and 420 min after the end of the meal consumption. Cholesterol and triacylglycerols were determined in serum and chylomicrons. A significant water consumption effect was observed in the total area under the curve (TAUC) of serum and chylomicron triacylglycerols (ANOVA, P=0.008 and P=0.027, respectively). TAUC of serum triacylglycerols for bicarbonated mineral water 2 was significantly lower compared to low mineral water (Bonferroni, P=0.039). Peak concentration of serum triacylglycerols showed a significant water effect (P=0.025). Changes in chylomicron cholesterol were not significantly affected by the type of water. Bicarbonated mineral waters 1 and 2 did not show any significant differences. Drinking sodium bicarbonate-rich mineral waters reduces postprandial lipaemia in healthy postmenopausal women compared to drinking a low mineral water.

Analysis of Variance↗

Home-made carbonated water and the consumption of water and other beverages in children and adolescents: results of the DONALD study.

AIM: To determine differences in intake of water, drinking water and beverages between consumers (C) and non-consumers (NC) of carbonated water prepared at home. METHODS: Matched pairs design; 3-d-weighed diet records; participants of the DONALD Study (Dortmund Nutritional and Anthropometric Longitudinally Designed Study) aged 2-18 y (n = 550, mean: 8.2 y). RESULTS: The most important beverage was either carbonated (C: females 265, males 299 g/d) or bottled water (NC: males 267, females 282 g/d) followed by juice (120-174 g/d), soft drinks (134-167 g/d) and milk (84-149 g/d). Water intake from beverages was higher in males (NC: 902 and C: 906 g/d) than in females (NC: 789 and C: 771 g/d). However, total water intake per energy was higher in females (NC: 0.88 and C: 0.91 g/kcal) than in males (NC: 0.80 and C: 0.83 g/kcal). C had a significantly higher mean drinking water intake (tap + bottled + carbonated water) in percentage of total water intake (%TW) than NC, and lower mean intakes of milk, bottled water and tap water, respectively. There was a significantly lower mean fat intake in C (females: 32 and males: 33% of energy) versus NC (females: 34 and males: 36% of energy). Irrespective of carbonated water consumption, females had better drinking habits than males, with significantly higher mean intakes of water from food (%TW), water from beverages + food (%TW), and total water per energy. CONCLUSIONS: Drinking habits and total water intakes of consumers are quite similar to those of non-consumers of carbonated water. Females in general show more favourable drinking habits than males.

Adolescent↗

Effects of water sulfate concentration on performance, water intake, and carcass characteristics of feedlot steers.

Two hundred forty single-source, cross-bred steers (304 kg) were used to evaluate the effects of various water sulfate concentrations on performance, water intake, and carcass characteristics of feedlot steers. Cattle were stratified by weight and assigned within weight blocks to five water treatments. Averaged over time, actual water sulfate concentrations (+/- SEM) were 136.1 (+/- 6.3), 291.2 (+/- 15.3), 582.6 (+/- 16.9), 1,219.2 (+/- 23.7), and 2,360.4 (+/- 68.2) mg/L, respectively. Weather-related data were recorded. Increasing water sulfate concentration resulted in linear decreases in ADG (P < 0.01) and gain:feed ratio (P < 0.01) and a quadratic effect on water intake (P = 0.02) and tended to quadratically increase then decrease DMI (P = 0.13). Sulfate x period interactions were evident for DMI (P = 0.01), ADG (P < 0.01), and feed efficiency (P < 0.01). Time had quadratic effects on DMI, water intake, ADG, and feed efficiency (P < 0.01 for all models). Increasing water sulfate concentration resulted in linear decreases in final weight, hot carcass weight, and dressing percentage, a linear increase in longissimus muscle area, and a quadratic effect on fat thickness over the 12th rib and predicted yield grade (P < 0.05 for all dependent variables). Mean daily temperature explained 25.7% of the observed variation in water intake. Other factors that explained a significant (P < 0.01) amount of variation in water intake were BW, DMI, water sulfate concentration, barometric pressure, wind speed, and humidity. High water sulfate concentrations had a significant and deleterious effect on performance and carcass characteristics of feedlot steers. Increasing the sulfate concentration in water may have resulted in a functional water restriction early in the trial when ambient temperatures were greatest. However, toward the latter stages of the trial, cattle supplied higher-sulfate water had higher ADG and FE. These improvements later in the trial may represent compensatory gain associated with decreased ambient temperature and water requirements. Averaged over time, a water sulfate concentration of greater than 583 mg/L, equivalent to 0.22% of the diet, decreased feedlot performance.

Age Factors↗

[Ground water and health. Reflections based on analysis of water specimens from Hordaland and Vestfold].

Basically, Norway has an ample supply of water. The quality of Norwegian drinking water, however, is threatened, not the least because of pollution of surface water reservoirs. Ground water is better protected against pollution, and sub-surface water sources are being exploited more than before. At present, less than 15% of the Norwegian population uses ground water for household purposes, but the percentage is increasing rapidly Ground water is (normally) clean and has a good taste. A large number of elements can be traced in ground water; some of them in concentrations of significance for human health. The present paper reports elemental analyses of 150 water samples from ground water reservoirs in rock, collected in Vestfold (Eastern Norway) and Hordaland (Western Norway). Sixty-four elements were assessed using modern equipment such as ICP-MS. In most cases the chemical composition of the water was well within the limits set for good quality drinking water. For some of the elements one or more of the results exceeded the "highest acceptable concentrations" as defined by the Norwegian health authorities. This was the case for Al, As, Ba, Ca, Cd, F, Fe, Hg, K, Mg, Mn, Na, P, Pb, Rn and Zn. No drinking water standards have been established for Be, Mo, Th and U, which are of clear significance to the health. More research is needed to assess the relationship between drinking water chemistry and human health. The authors call for a systematic analysis of all Norwegian ground water wells, and emphasise the need for regular quality control, even of small, private water supplies.

Humans↗

Assessment of drinking water quality of Borg el-Arab water purification plant.

Borg El-Arab drinking water purification plant takes its raw water from El-Noubaria Canal at the kilometer 95. EI-Noubaria canal gets its water from the Nile at two points. The main bulk of water comes from El-Riah El-Behiery, while the second source of water coming from El-Riah El-Nassery. There are four agricultural drains at the kilometer 53.0, 66.0, 71.9 and 85.4 which return back to the canal and represent the sources of pollution of the canal. Chemical, physical and trace elements analysis were carried out for raw and treated water of Borg El-Arab drinking water purification plant. It was found that the quality of treated water for the different parameter, are in agreement with the Ministry of Health Decree No 108/1995 for drinking water. Regarding total dissolved solids level, the quality of water was fair during Autumn and Summer as its value was 876.7 mg/l and 701.2 mg/l respectively, it was poor during spring as it reached 1113 mg/l, while during winter it was unacceptable (1312.7 mg/l) which exceed the higher permissible limit of the Ministry of Health Decree No 108/1995. This high TDS values make objectionable tastes in the public water supplied to Borg El-Arab city and the North West coast summer resorts. This taste of water provides no assurance to the public that such water is free of pathogens or toxic inorganic chemicals. So, we recommend El-Hager canal as new intake source for providing Borg El-Arab drinking water purification plant with raw water free from pollutants and low in total dissolved solids concentration.

Egypt↗

Plant water relations at elevated CO2 -- implications for water-limited environments.

Long-term exposure of plants to elevated [CO2] leads to a number of growth and physiological effects, many of which are interpreted in the context of ameliorating the negative impacts of drought. However, despite considerable study, a clear picture in terms of the influence of elevated [CO2] on plant water relations and the role that these effects play in determining the response of plants to elevated [CO2] under water-limited conditions has been slow to emerge. In this paper, four areas of research are examined that represent critical, yet uncertain, themes related to the response of plants to elevated [CO2] and drought. These include (1) fine-root proliferation and implications for whole-plant water uptake; (2) enhanced water-use efficiency and consequences for drought tolerance; (3) reductions in stomatal conductance and impacts on leaf water potential; and (4) solute accumulation, osmotic adjustment and dehydration tolerance of leaves. A survey of the literature indicates that the growth of plants at elevated [CO2] can lead to conditions whereby plants maintain higher (less negative) leaf water potentials. The mechanisms that contribute to this effect are not fully known, although CO2-induced reductions in stomatal conductance, increases in whole-plant hydraulic conductance and osmotic adjustment may be important. Less understood are the interactive effects of elevated [CO2] and drought on fine-root production and water-use efficiency, and the contribution of these processes to plant growth in water-limited environments. Increases in water-use efficiency and reductions in water use can contribute to enhanced soil water content under elevated [CO2]. Herbaceous crops and grasslands are most responsive in this regard. The conservation of soil water at elevated [CO2] in other systems has been less studied, but in terms of maintaining growth or carbon gain during drought, the benefits of CO2-induced improvements in soil water content appear relatively minor. Nonetheless, because even small effects of elevated [CO2] on plant and soil water relations can have important implications for ecosystems, we conclude that this area of research deserves continued investigation. Future studies that focus on cellular mechanisms of plant response to elevated [CO2] and drought are needed, as are whole-plant investigations that emphasize the integration of processes throughout the soil--plant--atmosphere continuum. We suggest that the hydraulic principles that govern water transport provide an integrating framework that would allow CO2-induced changes in stomatal conductance, leaf water potential, root growth and other processes to be uniquely evaluated within the context of whole-plant hydraulic conductance and water transport efficiency.

Journal Article↗

Interactive effects of dietary copper, water copper, and Eimeria spp. infection on growth, water intake, and plasma and liver copper concentrations of poults.

The effects of dietary Cu, water Cu, and coccidial infection on poult growth performance and selected tissue mineral concentrations were investigated in a 10-d experiment using 200 5-d-old Nicholas toms (five replicates of 5 poults each; initial weight = 85 g). Uninfected and coccidiosis-infected (Eimeria meleagrimitis, Eimeria dispersa, Eimeria adenoeides, and Eimeria gallopavonis; cocci) poults were assigned to two levels of dietary Cu [Basal (B) and B + 204 mg Cu/kg diet on Days 1 to 10] and two levels of water Cu (0 and 103 mg Cu/kg water on Days 6 to 10). Dietary Cu and water Cu (main effects) did not affect (P > .10) gain, feed intake, gain:feed, water intake, hemoglobin, hematocrit, or liver Fe and Zn concentrations. Dietary Cu and water Cu increased (P < .03) liver and plasma Cu concentrations. The combination of dietary Cu and water Cu increased plasma Cu more than the sum of the Cu additions (dietary Cu by water Cu, P < .08). Coccidial infection reduced (P < .07) gain, feed intake, gain:feed, water intake, and hemoglobin, and increased (P < .02) liver Zn. Water Cu reduced water intake in uninfected poults but increased water intake in coccidiosis-infected poults (water Cu by cocci, P < .07). Water Cu increased hemoglobin in uninfected poults but decreased hemoglobin in coccidiosis-infected poults (water Cu by cocci, P < .07). Water Cu increased plasma Cu and liver Cu more in coccidiosis-infected poults than in uninfected poults (water Cu by cocci, P < .02).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Ice-Water Immersion and Cold-Water Immersion Provide Similar Cooling Rates in Runners With Exercise-Induced Hyperthermia.

OBJECTIVE: To assess whether ice-water immersion or cold-water immersion is the more effective treatment for rapidly cooling hyperthermic runners. DESIGN AND SETTING: 17 heat-acclimated highly trained distance runners (age = 28 +/- 2 years, height = 180 +/- 2 cm, weight = 68.5 +/- 2.1 kg, body fat = 11.2 +/- 1.3%, training volume = 89 +/- 10 km/wk) completed a hilly trail run (approximately 19 km and 86 minutes) in the heat (wet-bulb globe temperature = 27 +/- 1 degrees C) at an individually selected "comfortable" pace on 3 occasions 1 week apart. The random, crossover design included (1) distance run, then 12 minutes of ice-water immersion (5.15 +/- 0.20 degrees C), (2) distance run, then 12 minutes of cold-water immersion (14.03 +/- 0.28 degrees C), or (3) distance run, then 12 minutes of mock immersion (no water, air temperature = 28.88 +/- 0.76 degrees C). MEASUREMENTS: Each subject was immersed from the shoulders to the hip joints for 12 minutes in a tub. Three minutes elapsed between the distance run and the start of immersion. Rectal temperature was recorded at the start of immersion, at each minute of immersion, and 3, 6, 10, and 15 minutes postimmersion. No rehydration occurred during any trial. RESULTS: Length of distance run, time to complete distance run, rectal temperature, and percentage of dehydration after distance run were similar (P >.05) among all trials, as was the wet-bulb globe temperature. No differences (P >.05) for cooling rates were found when comparing ice-water immersion, cold-water immersion, and mock immersion at the start of immersion to 4 minutes, 4 to 8 minutes, and the start of immersion to 8 minutes. Ice-water immersion and cold-water immersion cooling rates were similar (P >.05) to each other and greater (P <.05) than mock immersion at 8 to 12 minutes, the start of immersion to 10 minutes, and the start of immersion to every other time point thereafter. Rectal temperatures were similar (P >.05) between ice-water immersion and cold-water immersion at the completion of immersion and 15 minutes postimmersion, but ice-water immersion rectal temperatures were less (P <.05) than cold-water immersion at 6 and 10 minutes postimmersion. CONCLUSIONS: Cooling rates were nearly identical between ice-water immersion and cold-water immersion, while both were 38% more effective in cooling after 12 minutes of immersion than the mock-immersion trial. Given the similarities in cooling rates and rectal temperatures between ice-water immersion and cold-water immersion, either mode of cooling is recommended for treating the hyperthermic individual.

Journal Article↗

Monitoring of the three organophosphate esters TBP, TCEP and TBEP in river water and ground water (Oder, Germany).

The behaviour of the three organophosphate esters tributyl phosphate (TBP), tris(2-chloroethyl)phosphate (TCEP) and tris(2-butoxyethyl)phosphate (TBEP) during infiltration of river water to ground water has been investigated. The monitoring site is the Oder River and the adjacent Oderbruch aquifer. From March 2000 to July 2001, 76 ground water samples from monitoring wells located close to the Oder River and nine river water samples were collected. Additionally, influent and effluent samples from local waste water treatment plants, one sample of rain water and samples of roof runoff were collected. All samples were analysed by solid-phase-extraction followed by gas chromatography/mass spectrometry. TBP, TCEP and TBEP were detected at mean values of 622 ng l(-1), 352 ng l(-1), and 2955 ng l(-1), respectively in municipal waste water effluents. This points to a major input of these compounds into the Oder River by municipal waste water discharge. The concentrations of TBP and TBEP decreased downstream the Oder River possibly due to aerobic degradation. TBP, TCEP and TBEP were detected in ground water influenced predominantly by bank-filtered water. This demonstrates a transport of organic compounds by river water infiltration to ground water. TBP, TCEP and TBEP were also detected in rain water precipitation, roof runoff and ground water predominantly influenced by rain water infiltration. This hints to an input of these compounds to ground water by dry and wet deposition after atmospheric transport. Organophosphate esters were also detected in parts of the aquifer at 21 m depth. This demonstrates low anaerobic degradation rates of TBP, TCEP and TBEP.

Biodegradation, Environmental↗

Water relations, gas exchange, and nutrient response to a long term constant water deficit.

Wheat plants (Triticum aestivum) were grown for 43 days in a micro-porous tube nutrient delivery system. Roots were unable to penetrate the microporous tube, but grew on the surface and maintained capillary contact with the nutrient solution on the inside of the tube through the 5-micron pores of the porous tube. Water potential in the system was controlled at -0.4, -0.8, and -3.0 kPa by adjusting the applied pressure (hydrostatic head) to the nutrient solution flowing through the microporous tubes. A relatively small decrease in applied water potential from -0.4 to -3.0 kPa resulted in a 34% reduction of shoot growth but only a moderate reduction in the midday leaf water potential from -1.3 to -1.7 MPa. Carbon dioxide assimilation decreased and water use efficiency increased with the more negative applied water potentials, while intercellular CO2 concentration remained constant. This was associated with a decrease in stomatal conductance to water vapor from 1.90 to 0.98 mol m-2 s-1 and a decrease in total apparent hydraulic conductance from 47 to 12 micromoles s-1 MPa-1. Although the applied water potentials were in the -0.4 to -3.0 kPa range, the actual water potential perceived by the plant roots appeared to be in the range of -0.26 to -0.38 MPa as estimated by the leaf water potential of bagged plants. The amount of K, Ca, Mg, Zn, Cu, and B accumulated with each unit of transpired water increased as the applied water potential became less negative. The increase in accumulation ranged from 1.4-fold for K to 2.2-fold for B. The physiological responses observed in this study in response to small constant differences in applied water potentials were much greater than expected from either the applied water potential or the observed plant water potential. Even though the micro-porous tube may not represent natural conditions and could possibly introduce morphological and physiological artifacts, it enables a high degree of control of water potential that facilitates the investigation of many aspects of water relations not practical with other experimental systems.

Boron↗

Delineating ground water recharge from leaking irrigation canals using water chemistry and isotopes.

Across the Great Plains irrigation canals are used to transport water to cropland. Many of these canals are unlined, and leakage from them has been the focus of an ongoing legal, economic, and philosophical debate as to whether this lost water should be considered waste or be viewed as a beneficial and reasonable use since it contributes to regional ground water recharge. While historically there has been much speculation about the impact of canal leakage on local ground water, actual data are scarce. This study was launched to investigate the impact of leakage from the Interstate Canal, in the western panhandle of Nebraska, on the hydrology and water quality of the local aquifer using water chemistry and environmental isotopes. Numerous monitoring wells were installed in and around a small wetland area adjacent to the canal, and ground water levels were monitored from June 1992 until January 1995. Using the water level data, the seepage loss from the canal was estimated. In addition, the canal, the monitoring wells, and several nearby stock and irrigation wells were sampled for inorganic and environmental isotope analysis to assess water quality changes, and to determine the extent of recharge resulting from canal leakage. The results of water level monitoring within study wells indicates a rise in local ground water levels occurs seasonally as a result of leakage during periods when the canal is filled. This rise redirects local ground water flow and provides water to nearby wetland ecosystems during the summer months. Chemical and isotopic results were used to delineate canal, surface, and ground water and indicate that leaking canal water recharges both the surface alluvial aquifer and upper portions of the underlying Brule Aquifer. The results of this study indicate that lining the Interstate Canal could lower ground water levels adjacent to the canal, and could adversely impact the local aquifer.

Agriculture↗

Public perception of drinking water from private water supplies: focus group analyses.

BACKGROUND: Over four million Canadians receive their drinking water from private water supplies, and numerous studies report that these supplies often exceed the minimal acceptable standards for contamination. Canadians in rural areas test their water intermittently, if at all, and treatment of water from private supplies is not common. Understanding the perceptions of drinking water among residents served by private systems will enable public health professionals to better target education and outreach activities, and to address the needs and concerns of residents in their jurisdictions. The purpose of this study was to explore the drinking water perceptions and self-described behaviours and needs of participants served by private water systems in the City of Hamilton, Ontario (Canada). METHODS: In September 2003, three focus group discussions were conducted; two with men and women aged 36-65 years, and one with men and women 20-35 years of age. RESULTS: Overall, participants had positive perceptions of their private water supplies, particularly in the older age group. Concerns included bacterial and chemical contamination from agricultural sources. Testing of water from private supplies was minimal and was done less frequently than recommended by the provincial government. Barriers to water testing included the inconvenience of the testing process, acceptable test results in the past, resident complacency and lack of knowledge. The younger participants greatly emphasized their need for more information on private water supplies. Participants from all groups wanted more information on water testing, and various media for information dissemination were discussed. CONCLUSION: While most participants were confident in the safety of their private water supply, the factual basis for these opinions is uncertain. Improved dissemination of information pertaining to private water supplies in this population is needed. Observed differences in the concerns expressed by users of different water systems and age groups may suggest the need for targeted public education strategies. These focus groups provided significant insight into the public perception of private water supplies and the need for public health outreach activities; however, to obtain a more representative understanding of the perceptions in this population, it is important that a larger scale investigation be performed.

Adult↗

The efficiency of removal of lead and other elements from domestic drinking waters using a bench-top water filter system.

The efficiency of removal of lead (Pb) and other elements from natural drinking waters using a bench-top water filter system was evaluated in three recently-built houses in Sydney, Australia, and two from rural centres. In addition, one filter system was tested for copper (Cu), Pb and cadmium (Cd) under rigorously-controlled laboratory conditions using Sydney water. For two Sydney houses, the efficiency was evaluated using special filter cartridges concomitant with the ordinary filters. Waters after passing through the filter, was sampled when the filter had been exposed to '0', 50, 100, 150, 200, and 250 l respectively and were analysed for lead isotopes and lead concentrations by high precision isotope dilution mass spectrometry. Samples that passed through the filter after '0', 50, 150 and 250 l collections were analysed for four anions and 39 cations by various methods. Sydney water was fairly uniform in its anion and cation composition, whereas water from the two rural areas contained higher concentrations of Ca, Mg and HCO3. Effects of the filter on the water compositions can be summarised into three groups: (1) elements removed during filtration--Ca, Mg, Sr, Ba, Cu, Pb, Zn and Ni. With 'age' of the filter, the efficiency of removal for Pb was maintained in the two houses with Pb concentrations greater than 10 micrograms/l in the first flush water and was maintained for Cu through all concentrations. Ca, Mg, Sr and Ba were largely removed in the first 50 1 of usage. (2) Elements added during filtration--K, Rb, Ag and P. Except for Ag, which was present throughout the testing period, these elements were added only in the first filtration. (3) Elements unaffected by filtration--Al, Si, Na, Fe, Cl and F. Efficiency of Pb removal from tap water by this system depends generally on the initial Pb content in the water. However, it also seems to depend, to some extent, on Pb speciation and water composition, as found in earlier studies of natural waters. The control in filtering efficiency as a function of Pb speciation and chemical composition becomes more important at low initial Pb concentrations in the water. However, the Pb concentrations at which speciation and water composition appear to play a role in filter efficiency are so low that these factors, though scientifically interesting, have no relevance from a practical point of view, especially the impact on human health. Acidification of six sets of duplicate water samples, one sample immediately after collection and the other acidified after more than 2 weeks, showed negligible changes in Pb or Cu concentrations between duplicates.

Anions↗