SEARCH · PubMed Health

Results for “Drinking Water”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 37 records · Page 2Linked to original sources

PubMed1979

[The occurrence of salmonellae in drinking water (author's transl)].

A total of 7187 samples of drinking water from different areas of the Lower Saxonian District of Braunschweig was investigated according to regulations of the Trinkwasser-Verordnung during June 1977 and May 1979. The bacteriological results are given in Tab. 1 and 2. Salmonellae were isolated in three samples of drinking water and in one sample of sludge from a municipal pipe of drinking water (see also Tab. 2). Additional experiments confirm that growth of salmonellae and other enterobacteria is possible in that sludge (Fig. 1 and 2). These findings implicate some considerations: E. coli and coliforms are the most important microbial water quality indicators of the Trinkwasser-Verordnung. It is presupposed that, when the indicator density is low (less than 1 per 100 ml) the probability that pathogen are present also will be very low. But the question is how low. The risk factor may be estimated on the base of the E. coli-Salmonella ratio in raw sewage of about 10(6). But this relation lessens already in effluents of sewage treatment plants to 10(3) and it seems to be often 10(2) in inadequately disinfected drinking water. For example, we have found four Salmonella serotypes and 408 E. coli during two years. Therefore, the judgement of the presence of E. coli or coliforms in samples of drinking water must impact highly on the improvement of the water quality by disinfection in future.

Enterobacteriaceae↗

PubMed1975

Halogenated hydrocarbons in New Orleans drinking water and blood plasma.

Volatile organics from New Orleans drinking water and pooled plasma were collected on a solid phenyl ether polymer and analyzed by gas chromatographic and mass spectrometric techniques. Thirteen halogenated hydrocarbons were identified in the drinking water. Five halogenated compounds were found in the plasma. Tetrachloroethylene and carbon tetrachloride were found in both the plasma and the drinking water. Considerable variation in the relative concentrations of the halogenated hydrocarbons was noted from day to day in the drinking water.

Adult↗

PubMed1975

Fowl cholera: immunologic and werologic response in turdeys to live Pasteruella multocida vaccine administered in the drinking water.

Live fowl cholera vaccine administered in drinking water induced immunity in young turkeys against a challenge of a different immunogenic type of Pasteurella multocida; this is referred to as cross-immunity. Serum from the vaccinated birds induced passive cross-immunity in chicks and turkeys; this demonstrated that the cross-immunity induced with the drinking water vaccine was associated with the humoral system. Results of serologic tests with agar grown P. multocida indicate that agglutinins and precipitins are not associated with the induced cross-immunity. A live culture of P. multodica previously reported to induce cross-immunity in mature turkeys without causing adverse effects when administered in the drinking water, killed 6 of 45 (13 per cent) poults in the present study; this demonstrated that young turkeys are more susceptible to fowl cholera than mature turkeys.

Administration, Oral↗

PubMed2026

Occurrence of antibiotic-resistant E. coli and antibiotic resistance genes from culturable bacteria in drinking water sources along the Upper Mahaweli River, Sri Lanka.

Antibiotic-resistant Escherichia coli (AR-E. coli) and antibiotic resistance genes (ARGs) in aquatic environments pose a serious threat to public health. However, their presence in river water in South Asian countries is not well established. The present study investigated AR-E. coli and ARGs from culturable bacteria in drinking water sources from 14 drinking water treatment plants situated along the Upper Mahaweli River, a tropical central hill-country river system in Sri Lanka. A total of 167 E. coli isolates were tested against ten antibiotics using the Kirby-Bauer method, and genomic DNA from culturable bacteria in 45 water samples were screened for 11 ARGs using PCR. Overall, 60.48% E. coli isolates exhibited resistance to at least one antibiotic and multidrug resistance was detected in 27.54%. Highest resistance was for amoxicillin (47.31%), tetracycline (26.95%), and co-trimoxazole (24.55%) and four antibiotics showed seasonal variation. ARGs, dominated by blaTEM (80.0%), tetA (66.67%), and tetM and qnrS (62.22%) were detected in 42.42% PCR assays (n = 210). Multiple antibiotic resistance index varied from 0.00 to 0.80, with 44.91% exceeding the 0.2 threshold value, and the antibiotic resistance index varied from 0.00 to 0.32, with eight above the threshold (≥ 0.2). Hierarchical cluster analysis grouped majority of drinking water sources into the intermediate category while few were categorized under low (Kotagala and Thalawakelle-Galkanda) and high (Haragama, Paradeka, and Nawalapitiya), reflecting the variability of anthropogenic interference. Results highlight the risk associated with AR-E. coli and ARGs from culturable bacteria in one of Sri Lanka's key drinking water sources. Proactive interventions ensuring long-term safety of drinking water sources are urgently needed to safeguard public health.

Sri Lanka↗

PubMed1979

Can drinking water standards be reliably derived from industrial TLVs?

The accuracy of TLV derived drinking water standards is evaluated. When using the identical TLV conversion methodology which Stokinger and Woodward (1) used in deriving the standard for barium in drinking water, standards for arsenic, cadmium, chromium and lead offer 6, 200, 60, and 10 times less protection than the present drinking water standards, respectively. However, using the same methodology, the TLV derived drinking water standard for fluoride offers greater protection than the present standard by a factor of approximately 2. Thus, the use of the TLV conversion factor should be viewed in as one of many lines of potential evidence which should be reviewed in the standard derivation process - but it should not, if at all possible, be considered alone - as in the case of barium.

Arsenic↗

PubMed1975

[Comparative studies on the action of chlorine and ozone on polioviruses in the reprocessing of drinking water in Essen (author's transl)].

The present study was performed in order to evaluate comparatively the inactivation of polio virus type I strains (wild type and attenuated) by means of chlorine and ozone. Polio virus type I was chosen with regard to its epidemiological behaviour and high stability in drinking-water and sewage lines. In view of the lack of propagation techniques, hepatitis viruses A and B, unfortunately, could not be used for these experiments. The experiments were done under laboratory conditions only, and not in the water recovery plant because of hygienic reasons. Defined quantities of disinfectants were examined for their virus-inactivating effect in water without redox-potential (double-distilled water), water with low defined redox-potential (double-distilled water + KOH), previously chlorinated water with a residual chlorine content of 0.03 mg chlorine per liter (tap water) and water with a high redox-potential (well water from the drinking-water plant). Time-course studies were performed, both with chlorine and ozone, in order to evaluate the characteristics of the inactivation procedure. The experimental conditions chosen varied from experiment to experiment to obtain relevant conclusions for the practice. On the basis of our results, and taking into account the quantitative differences in effect, chlorine and ozone principially can be considered equivalent in their action of virus-disinfection. Both, the initial rate and the kinetics of virus disinfection are really identical. Both disinfectants are dependant on the condition of the water (redox-potential, pH etc.) to a great extent in their efficacy. Therefore, a decision of whether or not ozone should substitute for chlorine for the drinking-water supply in Essen cannot be drawn on the basis of virological experiments. This decision, then, depends more or less on other questions - such as relative costs and practicability of the ozonization on a large technical scale. The safety risk and technical reliability of the ozonization process is of particular significance. In the present condition of the Essen reservoir water, a good virus disinfection can be expected already with 1.0 to 1.5 mg ozone/liter (dissolved!); such a concentration guarantees very little residual ozone and, thus, makes then this procedure technically feasible. Continuous checking of the redox-potential and the amount of the ozone added is necessary. With regard to a continuous supply of ozone, the dependence on current supply must be guaranteed. Ozonization of water, probably by the cleavage of humic acid, promotes bacterial recontamination of the drinking-water in the city taps(Stalder und Klosterkötter, 45). Therefore only a combined pre-ozonization with subsequent chlorination would guarantee, both, safety and improvement of the cosmetical conditions of the drinking-water. Such a combination would be feasible with highly reduced amounts of ozone and chlorine.

Chlorine↗

PubMed1979

[Aquatic myxobacteria as indicators in the evaluation of drinking water quality (author's transl))].

Aquatic myxobacteria were shown to be good indicators of surface contamination of drinking water, or water filtered by an inadequate soil profile, both in experiments with sterilized or biologically active soil profiles, resp., and in actual comparison data obtained in practical drinking water analyses. In experimental investigations with artificial profiles, aquatic myxobacteria were retained to a considerably greater degree than E. coli or P. fluorescens due to stronger forces of adhesion. In a number of bacteriological drinking water analyses, this property was confirmed insofar as aquatic myxobacteria could regularly be demonstrated when inspecting hygienically deficient wells or springs. The confirmed presence of E. coli, on the other hand, showed a considerably lesser correlation with the results of on the spot evaluations of hygienic conditions. It must be urgently advised to include the search for aquatic myxobacteria in bacteriological drinking water analyses, since, contrary to the demonstration of E. coli, not only the actual but, in addition, the potential hazard of contamination of drinking water with bacteria present in superficial soil strata is indicated.

Bacteriological Techniques↗

PubMed1977

Interim results of two-year toxicological studies in rats of vinylidene chloride incorporated in the drinking water or administered by repeated inhalation.

Male and female Sprague-Dawley rats were exposed to vinylidene chloride (VDC) orally or by inhalation in 2-year toxicological studies. Interim results are included in this report. VDC was given in the drinking water at mean +/- S.D. concentrations of 0, 68 +/- 13, 106 +/- 22, and 220 +/- 35 ppm which produced mean +/- S.D. dosage levels of 0, 5.9 +/- 0.6, 10.0 +/- 1.2, and 19.3 +/- 2.7 mg/kg for male rats and 0, 7.5 +/- 0.4, 12.6 +/- 1.1, and 25.6 +/- 2.4 mg/kg for female rats. Forty-eight rats/sex/VDC level and 80 rats/sex in the control group were used in the 2-year study with an interim kill of an additional 10 rats/sex/level at 90 days. In the inhalation study, rats were exposed to 0, 10, or 40 ppm of VDC vapor 6 hr/day, 5 days/week for 5 weeks, after which the exposure levels were changed to 0, 25, and 75 ppm of VDC. Exposure continued for a total of 18 months and the rats held for observation an additional 6 months. Interim kills occurred at 1, 6 and 12 months. A separate 90-day study using 20 rats/sex/level was conducted at 0, 25, and 75 ppm of VDC vapor. There were 86 rats/sex/level in the 2-year portion of the study. The parameters monitored were: body weight, food and water consumption (drinking water study only), hematology, clinical chemistries, cytogentics of bone marrow cells (inhalation study only), mortality, terminal organ weights, and gross and histopathology. Based on interim kills and gross pathologic observations, the main conclusions are: increased cytoplasmic vacuolation of hepatocytes was seen in the livers of rats given 200 ppm VDC in drinking water or 25 or 75 ppm VDC vapor by inhalation; based on gross tumor count, tumor incidence in VDC-exposed rats was not greater than controls.

Animals↗

PubMed1975

Comparative study of four microporous filters for concentrating viruses from drinking water.

Four microporous virus-absorbent filter media for recovering low levels of virus from 380 liters of drinking water were compared. In addition two of the filter media were compared with 1,900 liters of drinking water. The filter media evaluated were MF nitrocellulose membranes (293 mm), AA Cox M-780 epoxy-fiberglass-asbestos disks (267 mm), K-27 yarn-wound fiberglass cartridges + AA Cox M-780 disks (127 mm), and Balston epoxy-fiberglass tubes (24.5 by 63.5 mm). The filters were used to concentrate seeded poliovirus from 380 liters of finished drinking water. Sodium thiosulfate was added to the drinking water to neutralize chlorine, and hydrochloric acid was added to adjust the pH to 3.5. Virus was eluted from the filters with glycine-NaOH buffer at pH 11.5. In terms of virus recovery efficiency, the filter media ranked Balston greater than Cox 267-mm greater than MF 293-mm congruent to K-27 + Cox 127-mm, but differences were slight. The Balston filters and holders were also superior to the other systems in terms of size, weight, cost, and handling factors. Experiments with 2- and 8-mum porosity Balston filters showed no statistically significant difference in virus recovery. Virus was readily detected by the Balston and the MF 293-mm systems at input levels of 12 to 22 PFU/1,900 liters. Preliminary experiments indicated that an elution pH lower than 11.5 may be satisfactory.

Asbestos↗

PubMed1975

Dehydrogenase activity of liver parenchyma in mice exposed to arsenic in drinking water.

The effect of arsenic administered in drinking water in the form of sodium arsenite in concentrations of 5,50 and 250 mg As-3+/1 on dehydrogenase activity (DHA) of liver parenchyma homogenate of exposed mice was studied. After an exposure lasting 2, 4, 8, 16, 32, and 64 days, 8--10 exposed mice and 5--10 animals of the control series were studied at each interval. DHA was determined by means of tetrazolium chloride reduction to formazan whose quantity was assessed spectrophotometrically after extraction with butanol. At a concentration of 5 mg A3+/1 a moderate increase in DHA was observed which was replaced by a moderate decrease at the following intervals. At a concentration of 250 mg A3+/1 a deep decrease in DHA (p smaller than 0.05) was recorded which did not return to values compararable with those of the control series in spite of its fluctuating increase in the course of exposure. At a concentration of 50 mg A3+/1 in drinking water ensuring the supply of doses which induce an increase in the tolerance to arsenic a decrease in DHA was found only at the first exposure interval. DHA is thus substantially less altered in comparison with the metabolic consumption of oxygen (MCO) under the same conditions. This finding signifies that MCO is a more sensitive indicator of arsenic exposure than DHA in the used arrangement of the experiment.

Animals↗

PubMedDate not supplied

Is EPA's radium-226 drinking water standard justified?

The U.S. Environmental Protection Agency's (EPA) proposed drinking water standard for radium-226 (226Ra) of 5 pCi/l is evaluated according to its health basis and carcinogenic implications. Proposed health risks of 226Ra in drinking water by other leading theoreticians (Evans, Gofman-Tamplin and Peterson) are also considered in light of the EPA proposal. It is concluded that the EPA proposal to raise the standard for 226Ra in drinking water is not justified on the basis of present knowledge of 226Ra carcinogenic effects.

Body Burden↗

PubMed1976

Effect of drinking waters of high fluorine content on the urinary fluoride level.

The urinary fluoride level has been studied in 307 subjects consuming drinking waters of different fluoride concentrations. The urinary fluoride level was found to increase with the fluoride content of the drinking water. The urinary F level of the population group drinking water of optimum fluoride concentration was 1.14 mg of fluoride per litre. Thus, in regions where the drinking water contains an insufficient amount of fluoride, the fluoride content of domestic salt must be adjusted so as to ensure an about 1.14 mg/litre urinary F level of the population.

Adolescent↗

PubMed1979

Viruses in drinking-water. Reconsideration of evidence for postulated health hazard and proposals for virological standards of purity.

Stringent virological standards for drinking-water have been proposed by the World Health Organisation and by others, but there is no evidence of the spread of virus infection by drinking-water that has been adequately treated to conventional bacteriological standards. There is evidence for waterborne transmission of hepatitis and viral gastroenteritis but the case for the introduction of virological standards is critically examined. It is concluded that there is no evidence that drinking-water in the U.K. contributes to the spread of virus infection, and that the introduction of virological standards for drinking-water could not at present be justified. Moreover, in the absence of any information relating the degree of viral contamination to disease, there is no logical basis on which to set the level of a practical virological standard.

Disease Outbreaks↗

PubMed1979

Drinking water quality and sudden death: observations from West and East Finland.

Relationships of drinking water quality to CHD and sudden death were studied in two rural areas in western and eastern Finland. In the eastern area, drinking water is particularly soft and contains less magnesium and chromium but more copper than in the western area. A 15-year follow-up of resident males showed a higher death rate from CHD in the eastern area but no difference in the proportion of sudden deaths. The data suggest that CHD may be associated with low concentrations of magnesium and chromium in the drinking water, but no definite relationship was found between water quality and sudden death.

Chromium↗

PubMed1979

Kinetics of Cl02 and effects of Cl02, Cl02-, and Cl03- in drinking water on blood glutathione and hemolysis in rat and chicken.

Since chlorination of drinking water produces organochlorinated substances (some possibly carcinogenic), the use of chlorine dioxide disinfectant would avoid halogenation. There is scarcely any data published on the effects of ClO2 in drinking water on human or animal health. The kinetics of 36ClO2 was studied in rats. Radioactivity was rapidly absorbed from the gastrointestinal tract following the administration of (0.07 microCi) 36ClO2 orally. 36Cl in plasma reached at peak at 1 hr. The half life for the elimination of 36Cl from the rat was 44 hr, corresponding to a rate constant of 0.016 hr-1. After 72 hr radioactivity was highest in plasma, followed by kidney, lung, stomach, duodenum, ileum, liver, spleen, thymus, and bone marrow. 36Cl excretion was greatest at 24 and 48 hrs after the administration of 36 ClO2. Forty-three percent of the total initial dose was excreted at 72 hr in the urine and feces. No 36 Cl was detected in expired air throughout the 72 hr studied. ClO2, ClO2-, and ClO3- (1, 10, 100, 1000 ppm) given daily in drinking water decreased blood glutathione, decreased osmotic fragility, and changed the morphology of erythrocytes in both chicken and rat after two months. Methemoglobin was not detected throughout these studies.

Animals↗

PubMed1978

Administration of a vaccine prepared from the Australian V4 strain of Newcastle disease virus by aerosol and drinking water.

An experimental vaccine containing the avirulent Australian V4 strain of Newcastle disease virus was used to vaccinate 3-or 6-week-old chickens by aerosol and drinking water application. The chickens lacked maternally derived antibody to Newcastle disease virus. When the vaccine virus was diluted in tap water more than 90% of the infectivity was destroyed immediately. The addition of 0.25% skim milk prevented this loss and there was no loss in distilled water. Rates of inactivation at 37 degrees C were similar in tap water and distilled water and were unaffected by the addition of skim milk. Both methods of vaccination resulted in the production of haemagglutination-inhibition antibodies which persisted for at least 8 to 12 weeks. The antibody response to aerosol vaccination was significantly better than that following drinking water vaccination. No clinical disease was induced by exposure to vaccine virus. Serum neutralisation antibodies paralleled those detected by haemagglutination-inhibition in chicks vaccinate once by drinking water. After revaccination through the drinking water, haemagglutination-inhibition antibodies were boosted temporarily while neutralising antibodies were maintained at an enhanced level. From chickens vaccinated by aerosol, Newcastle disease virus was recovered for 10 days from lungs and for 7 days from tracheas and caecal tonsils. Peak viraemia was detected 2 and 3 days after vaccination while both neutralising and haemagglutination-inhibition antibodies became detectable 5 days after vaccination.

Aerosols↗

PubMed1975

Water drinking and outflow facility.

In a series of patients with ocular hypertension, the effect of water drinking upon pressure and outflow facility was determined by impression (Schiotz) tonometry and tonography. The statistical facility-depressing effect of water drinking revealed by numerous earlier studies was confirmed, but found to be too small to be readily demonstrable in the individual eye. The water-drinking test in patients with primary ocular hypertension presents a situation in which tonography adds little to the information provided by tonometry.

Aqueous Humor↗

PubMed1979

Blood levels of sulfamethazine achieved in beef calves on medicated drinking water.

Studies on the use of sodium sulfamethazine in drinking water at three levels (572, 1028 and 1848 mg/L) were conducted in healthy weaned beef calves under similar dietary and environmental conditions. Blood sulfonamide levels greater than 5 mg/dl were attained with each treatment level but at different time intervals. The maximum levels in blood were achieved with the highest concentration in the water. However, a reduction in water intake caused a lower than anticipated dose of sulfamethazine. Under the conditions of the experiment the administration of sulfonamide in drinking water may be an effective means of mass medication of cattle.

Animals↗