Pilot-scale study on seeded precipitation assisted nanofiltration for flue-gas desulfurization wastewater softening.

In order to reduce the cost of chemical softening, the seeded precipitation assisted nanofiltration (NF) process was introduced into zero liquid discharge (ZLD) of flue-gas desulfurization (FGD) wastewater treatment. A pilot-scale system was developed and run for 168 h in a coal-fired power plant. The system mainly consists of lime softening, ambient temperature crystallizer (ATC) and NF, in which the raw water treatment capacity was 1 m3/h. The results indicated that the system operated stably, the softening cost was 13.30 RMB/m3, and the electricity cost was 3.39 RMB/m3 for the FGD wastewater in this pilot system. High quality gypsum was got from the ATC unit, of which the purity was 95.8%. Through this system, the hardness removal rate was higher than 98.9% and the water recovery rate reached 96%. In addition, the pressure and permeate flux kept stable in the ultrafiltration (UF) unit and NF unit, indicating no scaling occurred in the two units during 168 h test. Thus, a feasible and cost-effective process was provided by using the seeded precipitation assisted NF to deal with the FGD wastewater.

Contribution of Drinking Water Softeners to Daily Phosphate Intake in Slovenia.

The cumulative phosphate intake in a typical daily diet is high and, according to several studies, already exceeds recommended values. The exposure of the general population to phosphorus via drinking water is generally not known. One of the hidden sources of phosphorus in a daily diet is sodium polyphosphate, commonly used as a drinking water softener. In Slovenia, softening of drinking water is carried out exclusively within the internal (household) drinking water supply systems to prevent the accumulation of limescale. The aim of the study was to determine the prevalence of sodium phosphates in the drinking water in Slovenia in different types of buildings, to determine residents' awareness of the presence of chemical softeners in their drinking water, and to provide an exposure assessment on the phosphorus intake from drinking water. In the current study, the presence of phosphates in the samples of drinking water was determined using a spectrophotometric method with ammonium molybdate. In nearly half of the samples, the presence of phosphates as water softeners was confirmed. The measured concentrations varied substantially from 0.2 mg PO4/L to 24.6 mg PO4/L. Nearly 70% of the respondents were not familiar with the exact data on water softening in their buildings. It follows that concentrations of added phosphates should be controlled and the consumers should be informed of the added chemicals in their drinking water. The health risks of using sodium polyphosphate as a drinking water softener have not been sufficiently investigated and assessed. It is highly recommended that proper guidelines and regulations are developed and introduced to protect human health from adverse effects of chemicals in water intended for human consumption.

Eventos adversos en la terapia farmacológica de la enfermedad inflamatoria intestinal / Adverse events associated with the treatment of inflammatory bowel disease

Background: The purpose of inflammatory bowel disease (IBD) treatment is to achieve resolution of symptoms and remission of disease with a minimum of adverse events (AE). Aim: To report AE of different prescriptions used for the treatment of IBD. Material and Methods: Analysis of a registry of patients with IBD held at a private clinic from 1976 to 2013. All used medications, the occurrence and severity of AE were recorded. Results: The records of 346 patients aged 16 to 86 years, 74% with ulcerative colitis, were analyzed. The most commonly type of medications prescribed were 5-aminosalicylates (5-ASAs) in 329 patients (92%), followed by adrenal steroids in 218 (61%). Forty nine AE were recorded in the same number of patents (14%). These were more common in patients with Crohn disease (n = 19, 21%). An univariate analysis, demonstrated that extra-intestinal manifestations, hospitalizations secondary to IBD crisis, requirement of surgery and treatment with steroids, immunosuppressants or biologic agents were significantly associated with the presence of AE. AEs were more common with immunosuppressants, followed by 5-ASAs and steroids. Discontinuation of therapy was required in 79, 100 and 43% of patients taking these medications, respectively. Twenty percent of AEs were severe. Leukopenia and pancytopenia along with alopecia were the most common AEs attributable to azathioprine. Conclusions: The occurrence of AEs in patients with IBD is uncommon. Even inmunosuppressants or biologic agents have a low rate of AE and most of them mild.

Natural clinoptilolite composite membranes on tubular stainless steel supports for water softening.

Disk membranes generated from high-purity natural clinoptilolite mineral rock have shown promising water desalination and de-oiling performance. In order to scale up production of these types of membranes for industrial wastewater treatment applications, a coating strategy was devised. A composite mixture of natural clinoptilolite from St. Cloud (Winston, NM, USA) and aluminum phosphate was deposited on the inner surface of porous stainless steel tubes by the slip casting technique. The commercial porous stainless steel tubes were pre-coated with a TiO2 layer of about 10 µm. Phase composition and morphology of the coating materials were investigated using X-ray diffraction and scanning electron microscopy. Water softening performance of the fabricated membranes was evaluated using Edmonton (Alberta, Canada) municipal tap water as feed source. Preliminary experimental results show a high water flux of 7.7 kg/(m(2) h) and 75% reduction of hardness and conductivity in a once-through membrane process at 95 °C and feed pressure of 780 kPa. These results show that natural zeolite coated, stainless steel tubular membranes have high potential for large-scale purification of oil sands steam-assisted gravity drainage water at high temperature and pressure requirements.

Dechlorination by ultraviolet radiation: a suitable alternative to activated carbon in dialysis water systems?

Chlorine-based products are widely used in the water supply industry, and the potential for adverse effects in the haemodialysis setting is well documented. To date, the most commonly used method of chlorine removal has been granular activated carbon filters. An increasingly popular method of dechlorination is the use of high intensity, broad-spectrum UV systems to reduce both free chlorine and combined chlorine compounds (chloramines) into easily removed by-products. UV radiation has been successfully used in the pharmaceutical and food industries to destroy free chlorine and/or chloramines present in water, and kill all known spoilage microorganisms including bacteria, viruses, yeasts and moulds (and their spores). This nonchemical method can offer significant advantages and benefits compared to conventional dechlorination technologies currently employed in dialysis water systems. Whilst UV treatment at 254 nm wavelength has been routinely used for disinfection purposes in dialysis water systems, this paper considers whether UV radiation can be used as an alternative to more traditional methods of chlorine removal.

Interactions between chloride and sulfate or silica removals from wastewater using an advanced lime-aluminum softening process: equilibrium modeling.

Interactions among chloride, sulfate, and silica removals from recycled industrial wastewater using an ultra-high lime with aluminum process (UHLA) were studied. An equilibrium model that is able to accurately predict the chemical behavior and interactions between chloride and sulfate or silica with UHLA at various initial conditions and chemical reagents was developed. X-ray diffraction (XRD) analysis was conducted to identify the precipitated solids formed in the UHLA process. Model predictions indicated that simultaneous removal of sulfate and chloride can be best described by the formation of a solid solution containing calcium chloroaluminate, calcium sulfoaluminate (ettringite), calcium monosulfate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate. However, simultaneous removal of silica and chloride can be best described by precipitation of calcium silicate and calcium aluminosilicate in addition to a solid solution containing calcium chloroaluminate, tricalcium hydroxyaluminate, and tetracalcium hydroxyaluminate. The XRD results indicated the presence of the same solids assumed by the equilibrium model.

Effects of time and point-of-use devices on arsenic levels in Southeastern Michigan drinking water, USA.

Health effects associated with chronic, low-level exposures to arsenic in drinking water (<100 microg/L) remain unclear, in part due to uncertainties in assessing exposure. Drinking water concentrations have been used to assess past exposure to arsenic in epidemiological studies, under the assumption that a single measurement can be used to estimate historical exposure. This study aims to better understand (1) temporal variability in arsenic concentrations in drinking water and (2) the impact of point-of-use (POU) treatment devices on arsenic exposure measurements, and on reliability of the exposure measurement for population-level studies. Multiple drinking water samples were collected at two points in time (an average of fourteen months apart) for 261 individuals enrolled in a case-control study of arsenic exposure and bladder cancer in Michigan. Sources of drinking water included private wells (n = 221), public water supplies (n = 33), and bottled water (n = 7); mean arsenic concentration was highest in private wells (7.28 microg/L) and lowest in bottled water samples (0.28 microg/L). Arsenic concentrations in primary drinking water samples were highly correlated (r = 0.88, p < 0.0001, n = 196), with 3% of the water sources exceeding the United States Environmental Protection Agency's Maximum Contaminant Level (MCL) in one sample but not in the other sample. Measurement reproducibility did not vary by type of POU device (e.g., softener, filter, reverse osmosis system). Arsenic concentrations did differ, however, between samples treated with POU devices and untreated samples taken on the same day. Substantial differences in arsenic concentrations were consistently observed for reverse osmosis systems; other POU devices had variable effects on arsenic concentrations. These results indicate that while a single residential arsenic measurement may be used to represent exposure in this region, researchers must obtain information on changes in water source and POU treatment devices to better characterize population exposures over time.

Water treatment for hemodialysis--updated to include the latest AAMI standards for dialysate (RD52: 2004) continuing.

While nurses may not routinely service the water treatment system or mix the dialysate, they are responsible for understanding all the clinical ramifications of water and dialysate for HD and helping to piece together the entire treatment picture. Although historically the water treatment system has been in the technicians' domain, knowing the technical aspects is important in order for the entire team to work together toward the patients' ultimate well being. This article describes the composition of water treatment systems for hemodialysis as well as the monitoring and testing necessary to assure that both water and dialysate are safe for patient use.

Use of water 'softening and conditioning systems' significantly increases the risk of periodontitis: smoking considerations.

BACKGROUND: The role of water in the etiology of periodontal disease is poorly understood. OBJECTIVES: The objective of this study was to examine the association amongst water softness, risk for periodontitis, and smoking status. METHODS: We examined the association between use of water 'softening and conditioning systems' and the risk for periodontal disease in smokers and non-smokers, using adult participants (18+ years), from the third National Health and Nutrition Examination Survey (NHANES III) data. Zero to 33 per cent (0-33%) of sites with periodontal attachment loss > or = 3 mm was considered a healthy periodontium, and > 33% of sites with periodontal attachment loss > or = 3 mm was defined as periodontitis. Soft water users were divided into 'yes' or 'no' using the question, 'Does your home have a "softening or conditioning system?".' Smoking subjects were divided into groups as follows: current smokers (had smoked > or = 100 cigarettes in their lifetime and currently smoked), former smokers (had smoked > or = 100 cigarettes in their lifetime, not currently smoking), or never smokers (had not smoked > or = 100 cigarettes in their lifetime). Data was analyzed by univariate analyses using SPSS. The 5% level of statistical significance was adopted throughout. RESULTS: Subjects that answered the question 'yes' to soft water use had a significantly higher risk of periodontitis (p < 0.05), adjusting for confounders. When mineral intake from foods was added to the model, the significance of periodontitis risk remained the same for the non-smoking, soft water-using subjects, whereas for the smoking, soft water-using subjects the risk for periodontitis increased significantly (p < 0.05) in most cases. CONCLUSIONS: Thus, use of water 'softening and conditioning systems' significantly increased the risk for periodontitis, and smoking increased this risk.

[Not Available]. / [Drinking water and long-term health effects]

The quality of drinking water is known to have positive or negative influences on human health. At present, in the industrialized countries microbiological contaminants in public water supplies are under control, due to the widespread introduction of effective disinfection and potabilization systems. However, of special interest are other public health problems linked with the presence of many water components or contaminants. Since the beginning of this century, fluoride showed to have beneficial effects on dental caries and the practice of adding fluoride to drinking water has been widely followed in many countries for reduction of dental caries. More recently, a large body of scientific information indicates that various characteristics related to water hardness are correlated with incidence of cardiovascular disease. Moreover, the discovery of the presence in drinking water of inorganic and organic contaminants with mutagenic/carcinogenic properties gives rise to public health concern.

Qualidade da agua: sua importancia em farmacias homeopaticas / Quality of water: its importance in homeopathic pharmacy

A discussäo da importância da qualidade da água utilizada em farmácias para o preparo de medicamentos homeopáticos e dos métodos de purificaçäo para obtençäo dessa água säo os princípios que nortearam esse trabalho. Na conduçäo do estudo, os objetivos que fixamos foram os seguintes: detectar a presença de contaminantes na água, avaliar os processos de purificaçäo e propor soluçöes para o controle da água. Para tanto foram analisadas amostras de água quanto à condutividade específica, além de testes por cromatografia gasosa e espectrofotometria de absorçäo atômica. Os resultados indicam que a água destilda pode ter uma qualidade de pureza bastante satisfatória, especialmente quando alguns cuidados relativos à água de abastecimento e à manutençäo do destilador forem observados. Testes de condutividade podem prover uma excelente indicaçäo da qualidade da água destilada que está sendo utilizada.

Mineral content and blood parameters of dying brown trout (Salmo trutta L.) exposed to acid and aluminum in soft water.

1. Whole body mineral content and blood parameters were monitored in dying brown trout exposed to acid (pH 4.5) and aluminium (12 mumol l-1) at low external calcium concentration (20 mumol l-1). 2. Fish surviving the treatment had elevated haematocrit, low plasma sodium levels, and low whole body sodium and potassium content. 3. Dying trout had haematocrit and plasma sodium levels similar to treatment survivors, but whole body mineral content was unaffected and moisture content increased. 4. Death was probably caused by redistribution of fluid from the extracellular compartment to the intracellular compartment.

Atividade bactericida de purificadores de água de uso doméstico / Bactericide activity of water purifier of domestic use

O presente trabalho tem por objetivo avaliar a efetividade de purificadores de água na eliminaçao de bactérias coliformes e bactérias mesófilas aeróbicas. Foram testados quatro sistemas de filtraçao de água: 1 OZONIZADOR + VELA DE CELULOSE, 2 OZONIZADOR + VELA DE PORCELANA POROSA, 3 OZONIZADOR e 4 VELA DE PORCELANA POROSA. Os resultados demonstraram que nenhum sistema de filtraçao entre os estudados foi eficiente na eliminaçao total das bactérias comuns na água, porém para atender a nossa legislaçao, que estabelece padroes para coliformes, dois sistemas podem ser recomendados: OZONIZADOR + VELA DE PORCELANA POROSA e VELA DE PORCELANA POROSA. Estes sistemas eliminam ou reduzem a contaminaçao por bactérias coliformes

What is the value of plasma/serum aluminum in patients with chronic renal failure?

In a region with a relatively low incidence of aluminum toxicity water, dialysis fluid and plasma aluminum were monitored in hemodialysis patients before and after the introduction of reverse osmosis (RO) water. Before the use of RO water, there was a close correlation between plasma and dialysis fluid aluminum with exposure to aluminum being reflected equally by either water, dialysis fluid or plasma aluminum. Patients with clinical manifestations of aluminum toxicity were characterised by a plasma aluminum consistently greater than mumol/l and a dialysis fluid aluminum consistently greater than 1 mumol/l. No evidence of clinical toxicity was found in patients in whom the plasma aluminum was maintained up to 5 mumol/l. Following the introduction of RO water, the dialysis fluid aluminum was able to be maintained less than 1 mumol/l, the plasma aluminum fell and no new cases of clinical toxicity were identified over the following five years. An effect of aluminum hydroxide dosage on plasma aluminum could be identified only in patients in whom the dialysis fluid aluminum was less than 1 mumol/l. Plasma aluminum was found to be a poor guide to bone stores but appeared to correlate better with the presence of bone toxicity than total bone aluminum. Regular monitoring of dialysis fluid and plasma aluminum is recommended as a means of detecting exposure to aluminum as well as the source of exposure and as a guide to the risk of clinical toxicity.

The use of ion exchange to remove aluminum from water used in hemodialysis.

Since the established techniques for removing aluminum from the water used in dialysis (reverse osmosis and deionization) are relatively complex and expensive, it was decided to investigate a number of simple ion-exchange techniques. In 48 of 217 tap water samples obtained from 61 home hemodialysis patients in southeast Scotland, the aluminum content exceeded 2 mumol/L (54 micrograms/L)--a level that has been associated with dialysis dementia and fracturing osteodystrophy. Dialysate prepared from this water after softening had approximately half this aluminum content, but in 17 instances the concentration still exceeded 2 mumol/L. In vitro studies showed that the anion-exchange resin IRA 400 (Rohm-Haas, Philadelphia) in the chloride phase was very effective at removing aluminum. A commercial water softener was modified by the addition of this resin, and installed in the home dialysis training unit at the Princess Alexandra Hospital in Brisbane. Over a 12-month period in which the tap water aluminum content averaged over 10 mumol/L (270 micrograms/L), the product water had an aluminum content consistently under 2 mumol/L, being under 1 mumol/L (27 micrograms/L) on 19 out of 20 occasions. The modified softener was regenerated with a saturated sodium chloride solution at 2-week intervals, using the manufacturer's protocol for the unmodified softener. Provided that dialysate and plasma aluminum levels are monitored on a regular basis, it is felt that this simple technique of aluminum removal may be appropriate for many home hemodialysis situations.

Radiography of healing dialysis osteodystrophy.

Characteristic skeletal changes of dialysis bone disease associated with multiple fractures were found in ten patients on prolonged regular (high aluminium) haemodialysis. A subsequent prospective investigation with serial radiography demonstrated healing approximately twelve months after a changed treatment regime. The treatment used was deionized or reverse osmosis water dialysis and renal transplantation. The typical osteomalacic and osteosclerotic changes and particularly metaphyseal sclerosis were found to be associated with more rapid clinical healing, whereas secondary hyperparathyroidism indicated delayed healing. It is suggested that plasma aluminium imbalance may lead to disturbance of bone formation with fractures, while healing is associated with normal serum aluminium levels and is manifested radiologically by osteosclerosis, particularly in the metaphyses.