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PubMed2001

Fenton oxidation of ethanol-washed distillation-concentrated benzo(a)pyrene: reaction product identification and biodegradability.

After multiple ethanol washings followed by distillation, concentrated benzo(a)pyrene (B(a)P) in ethanol (approximately 85 mg L(-1)) was treated by Fenton oxidation, where > 99.8% of B(a)P was removed under a pseudo-first-order reaction. GC-MS and HPLC analysis identified B(a)P-1,6-, -3,6-, and -6,12-dione as Fenton oxidation products; all of which are known to have lower toxicity than B(a)P. Microbial resistance experiments demonstrated that B(a)P-1.6-, -3.6-, and -6,12-dione are more easily degraded than B(a)P. These results indicate that the proposed treatment can be effectively applied to remediate B(a)P-contaminated soil.

Benzo(a)pyrene↗

PubMed2001

Combined steam distillation and electrochemical peroxidation (ECP) treatment of river sediment contaminated by PCBs.

A combined treatment process utilizing steam distillation followed by electrochemical peroxidation (ECP) has been utilized to remove >90% of the polychlorinated biphenyls (PCBs) in St. Lawrence River sediment and destroy 95% of the PCBs recovered in the condensate. 2 l of condensate were collected by boiling 500 grams of sediment containing approximately 4.3 mg PCBs. Most of the PCBs (82.3%) were recovered as a small volume (<1 ml) of yellow oil floating on the condensate and coating glassware surfaces. The aqueous phase PCBs (182 microg/l) were destroyed (95%) by three sequential ECP treatments at 16.8 degrees C and pH 5, utilizing 1 ml of H2O2 (3%) and periodically reversed current (0.75-1.0 A @ 10 volts). Oxidation is primarily mediated by hydroxyl radicals produced by the reaction of hydrogen peroxide with electrochemically generated ferrous iron (Fenton's reagent). This work suggests steam extraction, in combination with advanced oxidation technologies, provides an effective treatment strategy for contaminated solids.

Electrochemistry↗

PubMed2000

No involvement of lipid mediators in a guinea pig model of ultrasonically nebulized distilled water-induced bronchoconstriction.

An inhalation of ultrasonically nebulized distilled water (UNDW) induces bronchoconstriction only in asthmatics, but the mechanism underlying the response is not fully understood. We have reported that bronchoconstriction occurs immediately after UNDW is inhaled 20 min after an antigen challenge in guinea pigs. Our aim was to examine the role of lipid mediators in this response. Passively sensitized guinea pigs were anesthetized and artificially ventilated. A sulfidopeptide leukotriene receptor antagonist, KCA-757, and platelet-activating factor antagonists, Y-24180 and E6123, were administered i.v. 15 min after an aerosolized antigen challenge, and UNDW was inhaled 5 min later. KCA-757, Y-24180, or E6123 did not, significantly alter the UNDW-induced bronchoconstriction. Together with our previous data that thromboxane A2 receptor antagonists did not influence the UNDW-induced bronchoconstriction, the present results suggest that lipid mediators are not involved in the UNDW-induced bronchoconstriction in our guinea pig model.

Animals↗

PubMed1987

The effect of indomethacin on the refractory period occurring after the inhalation of ultrasonically nebulized distilled water.

We examined the involvement of inhibitory prostaglandins in refractoriness induced by repeated ultrasonically nebulized distilled water (UNDW) challenge. Six male subjects with asthma who developed both UNDW-induced bronchoconstriction and refractoriness after UNDW were studied on 3 separate days, 1 week apart. On each study day, subjects had an initial UNDW challenge. UNDW responsiveness was assessed with dose-response curves of UNDW volume output versus the percent fall in FEV1. The output provoking a 20% fall in FEV1 (PO20 UNDW) was calculated. FEV1 was measured again at 5-minute intervals until it returned to within 5% of baseline value. UNDW challenge was then repeated. On day 1, the two successive UNDW challenges were performed in absence of any treatment (control day). Before days 2 and 3, subjects received placebo capsules or indomethacin, 100 mg per day, in a double-blind, randomized fashion for 3 days. On both the control and placebo days, repeated UNDW inhalation provoked a significant increase in PO20 UNDW (p less than 0.01), indicating refractoriness. On the indomethacin day, the mean PO20 UNDW during the second UNDW challenge was not significantly different from that obtained during the initial test on that day (p greater than 0.05), indicating that refractoriness did not occur. We suggest that inhibitory prostaglandins are involved in the development of refractoriness after UNDW inhalation.

Adolescent↗

PubMed1995

Relationship between ultrasonically nebulized distilled water-induced bronchoconstriction and acetic acid-induced cough in asthmatic children.

BACKGROUND: Although wheezing and cough are the most common complaints in asthmatic persons, the mechanisms of hyperresponsiveness to bronchoconstriction and cough are nevertheless still unclear. OBJECTIVE: To investigate the common mechanisms between them, we studied the relationship between ultrasonically nebulized distilled water (UNDW) inhalation challenge and acetic acid (AA) inhalation challenge. In addition, we evaluated the effect of inhaled furosemide on both provocation tests by means of a placebo-controlled study. METHOD: In study 1 the UNDW, AA, and histamine inhalation challenges were performed in 40 asthmatic children (26 boys, aged from 7 to 16 years; mean +/- SD, 11.2 +/- 2.0 years). In study 2, 12 of the study 1 subjects (9 boys, 11.3 +/- 2.4 years) were subjected to each challenge test after inhalation of furosemide (10 mg/body square meters), or placebo (0.9% saline solution) on separate days. RESULTS: There was a good correlation between the provocative dose causing a 20% fall in forced expiratory volume in 1 second in the UNDW inhalation challenge (UNDW-PD20) and threshold dose causing cough in the AA inhalation challenge (R = 0.527; p < 0.001). There was no relationship either between UNDW-PD20 and the provocative concentration causing a 20% fall in the histamine inhalation challenge (histamine-PC20)(R = 0.384; p > 0.1), or between histamine-PC20 and the cough threshold (R = 0.308; p > 0.05). In study 2 neither bronchoconstriction nor bronchodilation after inhalation of furosemide was observed. Inhaled furosemide exerted a protective effect on UNDW-PD20 and cough threshold of the AA inhalation challenge (p < 0.01 and p < 0.01, respectively), but did not attenuate histamine-PC20 (p > 0.1). CONCLUSION: These data suggest that a common mechanism may cause hyperresponsiveness against both UNDW-induced bronchoconstriction and AA-induced cough in asthmatic children.

Acetates↗

PubMed2003

Cooperativity between pepsin and crystallization of calcium carbonate in distilled water.

Cooperativity between pepsin and crystallization of calcium carbonate in distilled water was studied. The results show that vaterite was formed under the influence of pepsin and the crystalline product was a composite of vaterite and pepsin. The component of this material was similar to that of nacre. At the same time, the crystallization of calcium carbonate had also an important effect on the secondary structure of the pepsin. The secondary structure of the pepsin was characterized through FT-IR technology. The result indicated that the pure pepsin is composed of 24.38% alpha-helices, 29.91% beta-sheets, 39.32% beta-turns and 6.49% random structures and the pepsin in the CaCO(3)-pepsin solution is composed of 2.09% alpha-helices, 93.304% beta-sheets, 4.592% beta-turns and 0.006% random structure. During the crystallization of the calcium carbonate from the pepsin solution, the secondary structure of the pepsin transformed. These results showed that there was cooperativity between the crystallization of vaterite and the pepsin. The cooperative mechanism is discussed.

Calcification, Physiologic↗

PubMed2001

Biogeochemical characterisation of a coal tar distillate plume.

The distillation of acidified coal tars for up to 50 years has given rise to a phenol plume approximately 500 m long, 50 m deep and containing up to 15 g l(-1) dissolved organic carbon (DOC) in the Triassic Sandstones aquifer. A conceptual biogeochemical model based on chemical and microbiological analysis of groundwater samples has been developed as a preliminary to more detailed studies of the controls on natural attenuation. While the development of redox zones and the production of methane and carbon dioxide provide evidence of natural attenuation, it appears that degradation is slow. The existence of sulphate in the plume indicates that this electron acceptor has not been depleted and that consequently methanogenesis is probably limited. Based on a simple estimate of sulphate input concentration, a half-life of about 15 years has been estimated for sulphate reduction. Geochemical modelling predicts that increased alkalinity within the plume has not led to carbonate precipitation, and thus within the limits of accuracy of the measurement, alkalinity may reflect the degree of biodegradation. This implies a loss of around 18% of the DOC over a 30-year period. Despite limited degradation, microbial studies show that there are diverse microbial communities in the aquifer with the potential for both anaerobic and aerobic biodegradation. Microbial activity was found to be greatest at the leading edge of the plume where DOC concentrations are 60 mg l(-1) or less, but activity could still be observed in more contaminated samples even though cells could not be cultured. The study suggests that degradation may be limited by the high phenol concentrations within the core of the plume, but that once diluted by dispersion, natural attenuation may proceed. More detailed studies to confirm these initial findings are identified and form the basis of associated papers.

Biodegradation, Environmental↗

PubMed1990

Plasma lidocaine levels and PaO2 with endobronchial administration: dilution with normal saline or distilled water?

STUDY OBJECTIVE: To determine whether water or 0.9% saline should be used as diluent for endobronchial drug administration. PARTICIPANTS: Twelve adult patients. INTERVENTIONS: Patients were endobronchially administered 2 mg/kg lidocaine as marker substance in either 10 mL 0.9% saline or 10 mL distilled water during general anesthesia. MEASUREMENTS AND MAIN RESULTS: The differences in mean lidocaine plasma levels at five minutes (water vs saline, 2.35 vs 1.59 micrograms/mL) and ten minutes (water vs saline: 2.67 vs 1.88 micrograms/mL) were significant (P less than .05). With the initial mean PaO2 being almost (157 mm Hg; F1O2, 0.3) in the two groups, there was a mean drop of about 60 mm Hg in the saline-diluent group, but only about 40 mm Hg in the water-diluent group one minute after administration (P less than .05). CONCLUSION: The use of water resulted in better absorption of lidocaine and less impairment of the PaO2.

Adult↗

PubMed1998

Augmentation of anti-tumor effects of methotrexate by distilled water on Dunn osteosarcoma in mouse air pouch.

The anti-tumor effects of hypoosmotic solution of MTX in distilled water (DW) on Dunn osteosarcoma were evaluated in mouse air pouches. Dunn osteosarcoma cell suspension (1 x 10[5] cells in 0.1 ml of medium) was inoculated into the mouse subcutaneous air pouch that had formed 7 days after the initial injection of air. Two hours after the inoculation of tumor cells, 5 ml of various concentrations of MTX (from 0 to 1 x 10[-3] M) dissolved in DW or PBS were injected into the air pouch. Five minutes later, the entire solution in the air pouch was aspirated. The mice were sacrificed 3 weeks after the inoculation of tumor cells and the air-pouch tissue was transected in the coronal plane with the largest area of tumor mass. The sections were stained with H&E and the area was measured with the NIH Image program. The largest area of tumor mass in the air pouch treated with 1 x 10(-3) M of MTX in DW was 11.8+/-3.4 mm2 (N = 5), which was significantly (P < 0.005) smaller than that in PBS (51.7+/-8.3 mm2). These findings suggested that hypoosmotic solution in DW might augment the anti-tumor effect of MTX on sarcoma cells.

Animals↗

PubMed2003

Influence of raw materials and distillation equipment on the heavy metal content of waste from an alcoholic anis-type beverage.

This study focused on the heavy metal content waste resulting from the production of an anis-type beverage. Although natural ingredients were used in the production process, the waste contains heavy metals and is considered hazardous. Several metals were found in the waste (Fe, Cu, Ni, Zn, Cr and Cd), with concentrations of Fe to 157.5, Cu to 82.5, Zn to 31 and Ni to 8.5mg/l. To collect information on the source of these metals, the residues of the herbs used for flavoring were examined for processes employing metallic and non-metallic pot stills. Herbs distillation residues were found to contain metals in non-metallic stills, e.g. aniseed residues from glass stills contained Cu up to 1.02 and Ni up to 0.9 mg/l. Fennel residues contained Ni up to 1.2 and Zn up to 6.6mg/l. The main source for the metals was the bronze pot stills. The metals were in complexed form in the solution. The existence of metals in the amorphous phase as shown by a SEM micrograph indicates forming of metal-organic complexes, also verified by HPLC. Complexation data can be used for selecting the proper wash treatment method. The formation of large molecules favors precipitation and chemi-sorption treatment methods.

Alcoholic Beverages↗

PubMed1999

Napalm as an energy resource: a study of the molecular weight distribution of polystyrene in napalm and its use in middle distillate fuels.

The large quantity of napalm that is currently being treated as hazardous waste represents a viable energy resource that is too valuable to waste. However, there are significant problems to be overcome before this material can be used as an energy source. The scientific and environmental problems include: the broad molecular weight distribution of polystyrene, solubility and compatibility in a fuel matrix, methods to ensure complete combustion, high benzene concentration, low flash point due to the presence of gasoline, and safety in transportation and handling. In this paper, we present data on the molecular weight distribution of the polystyrene present in the napalm mixture, extraction of the gasoline and benzene from napalm, solubility of napalm in middle distillate fuels, simulated burner characteristics of napalm fuel mixtures, and accelerated storage stability studies of napalm fuel mixtures.

Journal Article↗

PubMed2001

Analysis of 3,5,6-trichloro-2-pyridinol in urine samples from the general population using gas chromatography-mass spectrometry after steam distillation and solid-phase extraction.

We have developed a new method for the quantitative trace determination of 3,5,6-trichloro-2-pyridinol (TCPyr). TCPyr is a urinary metabolite specific to the organophosphorus pesticides chlorpyrifos and chlorpyrifos-methyl. After hydrolysis and separation of TCPyr from the urinary matrix using semi-automated steam distillation and solid-phase extraction on a new polystyrol-divinylbenzene copolymer (Isolute 101) the analyte was converted into its tert-butyldimethylsilyl derivative by N-tert-butyldimethylsilyl-N-methyltrifluoroacetamide (MTBSTFA). Separation and quantitative analysis were carried out by capillary gas chromatography and mass selective detection in selected ion monitoring mode. 2,6-Dibromophenol (DBP) was used as the internal standard. The detection limit was 0.05 microg/l; the limit of quantification was 0.1 microg/l urine. The relative standard deviation of the within-series imprecision was 4.2% at a concentration of 3.5 microg/l. The relative recovery was 104%. The new method was used to analyse the urine samples of 12 persons from the general population without known exposure to the above-mentioned pesticides. TCPyr concentrations between 0.27 and 6.6 microg/l urine were detected in all urine samples. This indicates that there is a baseline excretion of TCPyr in the general population. Four urine samples collected from workers who had applied chlorpyrifos were also analysed. In these samples TCPyr was found in concentrations from 4.7 to 7.9 microg/l.

Calibration↗

PubMed1999

Pseudolatex preparation using a novel emulsion-diffusion process involving direct displacement of partially water-miscible solvents by distillation.

Pseudolatexes were obtained by a new process based on an emulsification-diffusion technique involving partially water-miscible solvents. The preparation method consisted of emulsifying an organic solution of polymer (saturated with water) in an aqueous solution of a stabilizing agent (saturated with solvent) using conventional stirrers, followed by direct solvent distillation. The technique relies on the rapid displacement of the solvent from the internal into the external phase which thereby provokes polymer aggregation. Nanoparticle formation is believed to occur because rapid solvent diffusion produces regions of local supersaturation near the interface, and nanoparticles are formed due to the ensuing interfacial phase transformations and polymer aggregation that occur in these interfacial domains. Using this method, it was possible to prepare pseudolatexes of biodegradable and non-biodegradable polymers such as poly(D,L-lactic acid) and poly(epsilon-caprolactone), Eudragit E, cellulose acetate phthalate, cellulose acetate trimellitate using ethyl acetate or 2-butanone as partially water-miscible solvents and poly(vinyl alcohol) or poloxamer 407 as stabilizing agent. A transition from nano- to microparticles was observed at high polymer concentrations. At concentrations above 30% w/v of Eudragit E in ethyl acetate or cellulose acetate phthalate in 2-butanone only microparticles were obtained. This behaviour was attributed to decreased transport of polymer molecules into the aqueous phase.

Chemistry, Pharmaceutical↗

PubMed1999

A sub-boiling distillation method for the preparation of low carbon content water from urine samples for tritium measurement by liquid scintillation counting.

A new preparation method was developed for obtaining low carbon content water from urine samples for the measurement of tritium by a liquid scintillation counter. The method uses a simple and convenient subboiling distillation bottle. Many urine samples have been purified by this method and the change of tritium level in a tritium-handling radiation-worker was observed.

Carbon↗

PubMed1997

Effect of inhaled furosemide and cromolyn on bronchoconstriction induced by ultrasonically nebulized distilled water in asthmatic subjects.

BACKGROUND: Inhaled furosemide has been shown recently to produce a protective effect against bronchoconstriction induced by several indirect stimuli, including ultrasonically nebulized distilled water (UNDW). Since there is a close parallel between its experimental effects and those reported for cromolyn,/it has been suggested that they may share some common mechanisms of action. Their protective effect, however, has never been compared directly. In this study, therefore, we have investigated the ability of equal doses (30 mg) of inhaled furosemide and cromolyn to modulate bronchoconstriction induced by UNDW in a group of ten asthmatic patients. METHODS: Subjects with documented bronchial response to UNDW were enrolled in a randomized, double-blind, placebo-controlled study. Treatments were administered five minutes prior to increasing outputs of UNDW and the response was expressed as the provocative output causing a 20% fall in FEV1 (PO20, in mL/min) and as the output-response slope. RESULTS: Geometric mean PO20 increased from 1.53 to 4.05 mL/min (P < .0004) after furosemide. After inhaling the highest output of UNDW (5.2 mL/min), PO20 was not measurable in six of ten patients when pretreated with furosemide and in all patients when pretreated with cromolyn. This difference was statistically significant (P < .05). Geometric mean values of output-response slope significantly decreased from 13.6 to 2.97 after furosemide (P < .0001) and from 13.6 to 1.43 (P < .0002) after cromolyn. CONCLUSIONS: These results suggest that cromolyn has a slightly greater anti-reactive activity in UNDW-induced bronchoconstriction compared to furosemide.

Administration, Inhalation↗

PubMed2002

Room-temperature isopiestic distillation of in situ generated arsenious chloride and its application for the determination of trace level impurities in arsenious oxide.

The room-temperature vapor pressures of HCl and AsCl3 in the presence of hydrochloric acid have been utilized in situ for the removal of arsenious oxide matrix as AsCl3 by isopiestic distillation. Reagent purification, sample dissolution, and matrix separation have been carried out in one step with a clean environment for both analyte and analyst. Quantitative recoveries have been achieved for most of the elements including volatile elements. Blank levels were found to be in nanograms per gram of As2O3 despite use of common reagents and simple reaction vessel. The utility of the present method for the analysis of As2O3 samples has been demonstrated.

Arsenicals↗

PubMed2003

Efficiency of methods for Karl Fischer determination of water in oils based on oven evaporation and azeotropic distillation.

The efficiency of azeotropic distillation and oven evaporation techniques for trace determination of water in oils has recently been questioned by the National Institute of Standards and Technology (NIST), on the basis of measurements of the residual water found after the extraction step. The results were obtained by volumetric Karl Fischer (KF) titration in a medium containing a large excess of chloroform (> or = 65%), a proposed prerequisite to ensure complete release of water from the oil matrix. In this work, the extent of this residual water was studied by means of a direct zero-current potentiometric technique using a KF medium containing more than 80% chloroform, which is well above the concentration recommended by NIST. A procedure is described that makes it possible to correct the results for dilution errors as well as for chemical interference effects caused by the oil matrix. The corrected values were found to be in the range of 0.6-1.5 ppm, which should be compared with the 12-34 ppm (uncorrected values) reported by NIST for the same oils. From this, it is concluded that the volumetric KF method used by NIST gives results that are much too high.

Journal Article↗

PubMed1996

Microwave distillation-solid phase adsorbent trapping device for the determination of off-flavors, geosmin and methylisoborneol, in catfish tissue below their rejection levels.

Described is a rapid microwave-mediated steam distillation device for determining two predominant off-flavor compounds, geosmin and methylisoborneol, in catfish tissue. A microwave on-time of 10 min is needed to efficiently remove these off-flavor compounds from the sample matrix and trap them on a solid phase adsorbent. A minimal amount of organic solvent is used to elute the trapped compounds. The extract is then analyzed by gas chromatography with ion trap detection in the selective ion storage mode. Detection limits in the sub-parts-per-billion range are obtained with this method.

Animals↗