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PubMed2002

Ozone therapy and the activity of selected lysosomal enzymes in blood serum of patients with lower limb ischaemia associated with obliterative atheromatosis.

BACKGROUND: The paper compares the effects of ozone therapy and conventional balneological methods on health condition of patients with obliterative atheromatosis and on serum activity of three lysosomal enzymes. MATERIAL/METHODS: Sixty-four patients with lower limb ischaemia in the course of obliterative atheromatosis (without diabetes) were enrolled in the study. Thirty-two patients were treated with ozone administered by intravenous infusions and 30-minute aerosol oxygen-ozone baths. A comparative group was formed of 32 patients treated with traditional balneology. There was also a control group made up of 30 healthy subjects. Ozone therapy as well as traditional balneology were administered daily for the period of 10 days, excluding Saturdays and Sundays. Blood for biochemical analysis was collected from elbow vein in the following time intervals: 24 hours before ozone therapy or classical balneology, one hour after therapy and on the 10th day of treatment. The activity of cathepsin D, acid phosphatase and arylsulphatase as well as the levels of a-1-antitrypsin (protease inhibitor) were determined in blood serum of patients with obliterative atheromatosis. RESULTS: In patients who received ozone therapy the activity of analysed lysosomal hydrolases returned to the values typical for healthy subjects. Patients' general condition also improved. The use of traditional balneological methods did not result in any significant change either in the activity of lysosomal hydrolases, the level of a-1-antitrypsin or general condition of patients. CONCLUSIONS: Ozone therapy administered by intravenous infusions and aerosol oxygen-ozone baths of lower extremities yields much better therapeutic results in comparison with classical balneology.

Acid Phosphatase↗
PubMed2002

Ozonation of domestic secondary effluent for recycling and reuse--a pilot plant study.

In this study, a pilot plant combined ozonation with sand filtration is established. Wastewater from the secondary effluent was taken as the sample for looking into the feasibility of domestic wastewater recovery and recycling. At the beginning, a series of hydraulic analysis and ozone transfer tests was conducted in the bubble column reactor. From these tests, it was found that when the gas flow is controlled to within 0.2 to approximately 1.0 L/min and liquid flow within 0.5 to approximately 2.5 L/min, using series connected mixing tank model for our calculation, the result J (CSTR) is 1 to approximately 2. From the ozone transfer test it is known that the smaller the gas flow, the better the transfer rate, and the same pattern occurs on ozone gas concentration. After sand filtration and ozone treatment, the G/L ratio within the ozone column reactor can be maintained within 0.2 to approximately 0.4 and the ozone dosage within 8 to approximately 12 mg/L. The removal rate for coliform bacillus, BOD, turbidity and color is 99.96%, 62.2%, 89.6% and 67% respectively. After ozonation treatment, coliform bacillus content can be controlled under 10 CFU/mL, BOD under 10 mg/L, turbidity within 2.0 to approximately 2.5 (NTU), and color within 10.3 to approximately 13.7 degree. The recycled water is almost colorless and odorless, and is capable of reaching the reference standard for recycled water.

Conservation of Natural Resources↗
PubMed2002

Effects of ozone treatment on the biodegradability of sludge from municipal wastewater treatment plants.

The effects of ozone pretreatment on the biodegradability of municipal wastewater sludge were determined. Three types of experiments were conducted: anaerobic digestion, aerobic biodegradation, and denitrification using ozone-treated sludge as a carbon source. For 5 days, ozonated sludge at 0.1 gO3/g-SS showed about 2-3 times greater biodegradation compared to the raw sludge in both aerobic and anaerobic conditions. In anaerobic experiments, biodegradation increased with ozone dosage up to 0.2 gO3/g-SS. Further increase of ozone dosage did not improve the biodegradation. In aerobic condition, about 77% of the ozonated sludge at 0.1 gO3/g-SS could be biodegraded after 15 days and is compared with 36% degradation of the untreated sludge. Most of the biodegradation of the ozonated sludge occurred within 5 days while the raw sludge was biodegraded steadily throughout the experimental period. The biodegradation enhancement of ozonated sludge was confirmed in batch denitrification experiments.

Bacteria, Aerobic↗
PubMed2003

High-performance closed loop anaerobic digestion using pre/post sludge ozonation.

To maximize the sludge degradation efficiencies during anaerobic digestion, pre-ozonation of raw activated sludge and/or post-ozonation of anaerobically digested sludge were used in combination with a reactor operated without solid withdrawal (closed loop operation scheme). Out of the two studied configurations, the configuration with the post-ozonation of digested sludge was found to be superior with respect to degradation efficiencies, lower accumulation of total volatile solid (TVS) and lower required ozone dose. The TVS concentration in the reactor with post ozonation was found to be around 26 +/- 2 g/l at an average TVS loading of 0.6 kgTVS/m3 x d. The maximum TVS removal efficiencies were observed to be around 85% with average specific gas recoveries of 0.36 l CH4/gTVS fed. The ozone dose of 3% on the recycle sludge was found to be sufficient as it was observed that the higher ozone doses of 6% neither improved the TVS reduction efficiency nor reduced the TVS concentration in the reactor. The ozone requirements were estimated at around 0.054 gO3/gTVS removed or 0.045 gO3/gTVS fed. The soluble COD concentrations from the reactor ranged from 500-875 mg/l with negligibly small amount of VFA. The average COD in the centrate of the digested sludge was around 3000 mg/l suggesting the presence of colloidal COD in the reactors.

Bacteria, Anaerobic↗
PubMed2004

Influence of mass transfer on the ozonation of wastewater from the glass fiber industry.

The mass transfer rate (kLa) is one of the most important parameters in the ozonation of wastewater, because it frequently constitutes the rate-determining step. This study investigated the influence of kLa on the ozonation of glass fiber wastewater using a high-performance jet loop reactor (HJLR), which is well known for its high mass transfer property, and compared the results of this investigation with those obtained using the bubble column reactor. It was found that the higher kLa achieved by increasing the energy input did not lead to higher ozonation efficiency, since the reaction involving the OH radical was greatly hindered at the low pH produced as a result of ozonation. By maintaining the pH at a value greater than 8.0, the higher kLa in the HJLR reactor contributed to increasing not only the TOC removal of wastewater, but also the ozone consumption efficiency, as expressed by the specific ozone consumption. The specific ozone consumption in the HJLR reactor (7.1 g ozone/ g TOC) was 20% better than that in the bubble column reactor.

Glass↗
PubMed2004

Sludge treatment by ozonation--evaluation of full-scale results.

Ozonation of industrial and sewage sludge is a suitable process for minimizing the sludge production of activated sludge processes. The ozonation has the advantage for complete oxidation of volatile suspended solids (VSS) of combining partial sludge oxidation with subsequent biological oxidation. This paper describes the evaluation of two full-scale sewage sludge ozonation investigations for subsequent aerobic stabilisation as well as for subsequent anaerobic stabilisation compared to different sludge treatment processes. For both the anaerobic and aerobic application, sludge liquefying by release of 110 and 160 mg COD per g total suspended solids (TSS) has been reached at specific ozone consumption of 0.03 and 0.06 kg O3 per kg TSS, respectively. The subsequent biological treatment has reached a mass reduction of 20-35% for the aerobic and 19% for the anaerobic stabilisation. For both applications the specific ozone consumption was about 0.05 kgO3 per kg TSS to be treated. A comparison with mechanical and thermo-chemical sludge mass reduction methods shows that the mass reduction potential of ozonation is presently higher. Even though costs for sludge ozonation are higher compared to other methods, the optimisation potential for cost reduction of sludge ozonation is obvious from the results presented in this paper.

Bacteria, Aerobic↗
PubMed2004

Evaluation of electrochemically generated ozone for the disinfection of water and wastewater.

Effective wastewater treatment is critical to public health and well-being. This is especially true in developing countries, where disinfection of wastewater is frequently inadequate. People who live in these areas may benefit from wastewater disinfection using ozone. This study evaluated the ability of a new electrochemical process of ozone generation, which produced ozone continuously at high pressure and concentration by the electrolysis of water, to disinfect tap water and secondarily treated wastewater. Inactivation of Klebsiella terrigena, Escherichia coli, MS2 bacteriophage and poliovirus 1 was evaluated first in reverse osmosis (RO) treated water. Inactivation of K. terrigena (6-log), E. coli (6-log), MS2 (6-log) and poliovirus 1 (>3-log) was observed after 1 min of ozonation in a 1 L batch reactor. Experiments were then performed to assess the microbiological impact of disinfection using ozone on secondarily treated municipal wastewater. The effect of ozonation on wastewater was determined for total and faecal coliforms, bacteriophages and heterotrophic plate count (HPC) bacteria. Electrochemical ozone generators provided an effective, rapid and low-cost method of wastewater disinfection. Based on the results of this research, electrochemically generated ozone would be well suited to remote, small-scale, disinfection operations and may provide a feasible means of wastewater disinfection in developing countries.

Developing Countries↗
PubMed1992

[Inhibitory effect of S-1452, a specific thromboxane A2 receptor antagonist on the increase of airway responsiveness in dogs after ozone exposure].

We evaluated the inhibitory effect of S-1452, a specific thromboxane (Tx) A2 receptor antagonist on the increase of airway responsiveness in 7 dogs after ozone exposure. Airway responsiveness to inhaled methacholine (Mch) was determined by Astograph (7 Hz oscillation technique), and at the same time TxB2, 6-keto-prostaglandin (PG) F1 alpha, PGE2 levels and total cell counts in the bronchoalveolar lavage fluid (BALF) were measured. Ozone exposure was carried out for 2 hr at an ozone level of 3.04 +/- 0.02 ppm (mean +/- SEM). Airway responsiveness to Mch increased significantly after ozone exposure (p less than 0.01), and this hyperresponsiveness was inhibited significantly by pretreatment with S-1452 (p less than 0.02). TxB2 and PGE2 levels in BALF did not change after ozone exposure, but the levels of 6-keto-PGF1 alpha decreased significantly after ozone exposure (p less than 0.05). Total cell counts in BALF increased significantly after ozone exposure (p less than 0.02). The decrease of 6-keto-PGF1 alpha levels and the increase of total cell counts were not affected by pretreatment with S-1452. These results suggest that S-1452 is protective against the increase of airway responsiveness induced by ozone exposure, and that TxA2 plays an important role in the hyperresponsiveness. But hyperresponsiveness may not be induced by hyperproduction of TxA2, but by the relative increase of TxA2 to PGI2.

Animals↗
PubMed1992

[Effects of tropospheric ozone on human respiratory organs].

Ozone is a photochemical oxidant and by this property able to damage function and structure of respiratory epithelium resulting in diffuse inflammation of the respiratory tract. In physiopathological terms the reactions observed are similar to those of asthma by presenting an acute and reversible airway obstruction as well as a long lasting bronchial hyperresponsiveness. The harmful effects of ozone can occur in healthy subjects as well as in patients with preexisting bronchopulmonary diseases and are best correlated to the total inhaled dose of ozone. Therefore even moderate ozone concentrations inspired during vigorous exercise may have similar effects as high concentrations at rest. Although most of the acute effects of ozone on the respiratory tract are potentially reversible, there is however evidence of chronic health damage by repeated ozone exposure to populations in highly polluted areas. In conclusion it is nowadays accepted that acute exposure to ozone already at moderate concentrations can induce an acute asthmatic reaction in healthy human airways followed by a long lasting bronchial hyperresponsiveness. Thus, ozone has to be considered as a trigger in pathogenesis of asthmatic diseases, a hypothesis which seems to be supported by results of epidemiologic surveys.

Air Pollutants↗
PubMed2005

[Effect of organic acids adsorption on catalytic ozonation with metal oxides].

The effectiveness of ozonation, adsorption and catalytic ozonation with ferric hydroxide (FeOOH) and cerium dioxide (CeO2) as catalysts on removal of several organic acids were investigated. The organic acids selected were benzoic acid (BA), phthalic acid (PA), commercial humic acid (CHA), and humic acid of Songhua River water (SHA) concentrated with reverse osmosis (RO). FeOOH was active in catalytic ozonation of the non-adsorbable BA, with 45% of BA removal higher than ozonation alone. It was inactive in case of ozonation of PA, the adsorption of which on FeOOH caused 5% reduction of its concentration. CeO2 enhanced ozonation of PA that was strongly adsorbed, but not for the non-adsorbed BA. Oxalate ions as product of oxidation of PA were also removed by CeO2 catalytic ozonation. As adsorption of humic acids on CeO2 is stronger than that on FeOOH, its catalytic removal by CeO2 was more than by FeOOH. The activity of catalytic ozonation of humic acids was scavenged in case of competition for adsorption sites on the catalysts by inorganic anions.

Adsorption↗
PubMed2006

[Effect of inorganic ions on degradation of trace nitrobenzene in aqueous solution by catalytic ozonation].

The experiment investigated the effects of general inorganic ions in natural source water on the three processes of ozonation alone, ceramic honeycomb and modified ceramic honeycomb-catalyzed ozonation for degradation of trace nitrobenzene in aqueous solution. The removal rate of ozonation alone and modified ceramic honeycomb-catalyzed ozonation increased by 5.0% and 8.6% with the increase of the concentration of calcium ion (0-4 mg x L(-1)), and that of ceramic honeycomb-catalyzed ozonation reached the climax at the concentration of calcium ion 0.5 mg x L(-1) under the same experimental condition. The degradation efficiency of ozonation alone, ceramic honeycomb and modified ceramic honeycomb-catalyzed ozonation enhanced by 10.9%, 11.6% and 9.6% with the increase of the concentration of manganese ion (0-4 mg x L(-1)), respectively, and decreased by 8.6%, 11.5% and 8.9% with the increase of the concentration of bicarbonate ion (0-200 mg x L(-1)). The concentration of nitrate and sulfate ion had no remarkable effect on ozonation alone, but the removal rate of other two processes decreased with the increase of the concentration of nitrate and sulfate ion.

Calcium↗
PubMed2006

Treating open carious lesions in anxious children with ozone. A prospective controlled clinical study.

PURPOSE: To determine whether the treatment of dental caries with ozone was possible in apprehensive children and to ascertain whether ozone reverses caries in open single-surface lesions. Further, the influence of ozone on laser fluorescence was investigated. METHODS: 82 lesions in 28 children with at least two open single-surface lesions were assessed. The children were anxious and were judged by the referring dentist as non-treatable. For each test lesion, which was treated with ozone, a control lesion was left without ozone treatment. Hardness and laser fluorescence values were assessed and the changes for hardness and laser fluorescence values in the test lesion were compared with the values in the control lesion after 2, 4, 6, and 8 months. RESULTS: 94 percent of the children were treatable and 93% lost their dental anxiety. The hardness values improved significantly in the ozone-treated test lesions after 4, 6, and 8 months (P< 0.05) compared with baseline while the control lesions had no significant change in hardness at any recall interval. Comparing the differences between test and control teeth over time, the laser fluorescence values improved, however the improvement was not statistically significant (P> 0.05). The use of ozone resulted in an average reduction of 13% of the laser fluorescence values immediately after the ozone treatment.

Cariostatic Agents↗
PubMed1990

[Health effects of ozone as component of summer smog].

During the sunny summers of 1989 and 1990 in Germany the outdoor ozone levels repeatedly exceeded the value of the air quality guidelines proposed by the World Health Organization. Both in multiple sites within industrial polluted and in supposedly clean outside areas the ozone concentrations exceeded the value of 180 micrograms/m3. The following paper is intended to contribute to an understanding of the health effects of ozone. It compiles data and views on the formation and analysis of ozone, on its distribution as ambient ground level pollutant, on respiratory and common symptoms in man and on the toxicokinetics, responses and pathogenesis in experimental animals. Studies on healthy exercising adult volunteers exposed to 240 micrograms/m3 ozone in purified lab air or in ambient air revealed a significant influence on connections between forced vital capacity, forced expiratory volume, flow rate and peak expiratory flow rate and the pollutant. Exposure to lower ozone levels induced the same effects, but they were of smaller magnitude. Children aged 8-15 years exercising under field conditions showed decrements in lung function even at ozone levels well below 200 micrograms/m3. Restitution of lung function needs periods of several days, although the induction of effects is a matter of hours. The relevance of the transient pulmonary responses is widely unclear. Among patients with chronic obstructive pulmonary disease or asthma, the functional responsiveness to ozone is not greater than among healthy subjects. Interindividual differences in responsiveness occur but are not predictable. Information on chronic effects is rather limited.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

[Oxygen concentrators are not ozone concentrators].

Ozone is a constituent of the natural ambient atmosphere and occurs dependent on weather and environment in concentrations that can trigger airway inflammation. Oxygen concentrators are employed in oxygen long-term therapy and produce in the room air a mixture of concentrated oxygen and residual gases of unknown ozone concentration. Hence, we studied the ozone concentration of the air supplied by the oxygen concentrator, both under normal conditions in the room air and with increased ozone concentration of the air in the room. Both under room air conditions and under increased ozone concentrations of up to 12 ppm in the surrounding air the residual gas mixture of the air produced by the oxygen concentrator did not contain any ozone concentration beyond 0.005 ppm. This prompts us to suggest that the oxygen concentrators examined by use are ozone eliminators rather than ozone concentrators.

Air Pollution, Indoor↗
PubMedDate not supplied

Lipid peroxidation and activity of antioxidative enzymes in the rat model of ozone therapy.

Hypothetical, therapeutic effects of ozone were investigated in an animal model. One ml of oxygen or mixture of 40 micrograms ozone with oxygen were injected intraperitoneally to male rats for 10 days. Previously, rats had been poisoned with 50 ppm Cd2+ in drinking water for 12 weeks. Exhaustive treadmill running was applied to some animals before sacrification. Ozone injections increased iron-ascorbate-stimulated lipid peroxidation (LPO) in the liver and kidney, catalase (CAT) activity in the heart and glutathione S-transferase (GST) activity in the heart, kidney and liver. Oxygen increased GST activity in the brain and reduced glutathione peroxidase (GPX) activity in the kidney. Cadmium enhanced LPO in the liver and GST activity in the brain, heart, kidney and liver. In contrast to ozone, cadmium inhibited GPX activity in the brain, kidney and liver. Cadmium combined with ozone enhanced the changes of GPX activity in the kidney and liver, that of GST activity in the heart, kidney and liver as well as of CAT activity and LPO in kidney. The results suggest that ozone injections combined with tested factors may provoke an oxidative stress. The effects of ozone therapy can not be explained as the results of ozone action on the antioxidative enzymes in rat.

Animals↗
PubMed2005

Residual aqueous ozone determination by gas diffusion reverse flow injection analysis.

A novel system based on reverse flow injection analysis with a gaseous diffusion step (GD-r-FIA) has been developed for the analysis of ozone. It includes an automatic microburet injection system. The ozone diffuses through a microporous membrane of polyvinylidene difluoride (PVDF) from the donor stream to the acceptor stream containing nitrite ions. The nitrite concentration in the acceptor solution decreases due to the ozone reduction reaction. In this way, a simple indirect measurement of the ozone concentration can be performed using the Griess-Ilosvay reaction for the nitrite ion. This correlates with the decrease in absorbance of the azoic dye formed with the ozone concentration in the donor stream. The system has been optimised by investigating the effect of the nitrite concentration in the acceptor stream on the diffusion flow. The optimum nitrite concentration was set at 0.250 ppm with a flow rate of 1.5 ml/min. The efficiency of the ozone diffusion through the membrane was only 4.4%. This affects the average sensitivity, which is low (0.0092+/-0.0012 AU/ppm), although the detection limit is similar to that obtained with other reported methods (0.03 ppm). The main advantage of the system reported here is that it has a linear range that is an order of magnitude broader than those observed for other GD-FIA systems. This is especially useful for continuous monitoring systems, since the residual ozone concentration is normally between 0.05 and 5.0 ppm. Additionally, using the reverse flow injection analysis (FIA) technique minimises chemical consumption and residue generation. Finally, the stability of the ozone solution and the repeatability and reproducibility of the method have been studied.

Journal Article↗
PubMed1990

The relationship between EDU pre-treatment and C2H4 evolution in ozonated pea plants.

A soil drench of [Formula: see text] (EDU) (150 ppm) applied to 'Progress No. 9' pea plants 24 h before an acute ozone exposure (0.25 ppm, 4 h) completely protected the foliage from visible symptoms normally induced by the pollutant. In the absence of ozone, EDU-treated plants were found to emit the same amount of C(2)H(4) as plants not treated with EDU. Based on this evidence, EDU-induced tolerance to ozone could not have been attributed to the prevention of an interaction between ethylene and ozone (sensu Mehlhorn and Wellburn). In the presence of ozone, EDU-treated plants did not emit the burst of C(2)H(4) that normally occurs (sensu Craker), extending the observation that EDU-treated plants do not exhibit the adverse physiological responses normally caused by ozone. The classic C(2)H(4) biosynthesis inhibitor aminoethoxyvinylglycine (AVG) did not prevent ozone phytotoxicity, although it significantly reduced ethylene emission from the ozonated tissue.

Journal Article↗
PubMed1990

The long range transport of ozone within Europe and its control.

It is widely accepted that the ozone concentrations experienced during photochemical episodes over large areas of Europe may exceed levels at which adverse environmental effects could be expected. These peak ozone concentrations can be reduced by controlling atmospheric emissions of the hydrocarbon and nitrogen oxide precursors. For ozone control to be successful over the spatial scale of Europe, long term international cooperation is required in the formulation of emission abatement strategies. A significant barrier to rapid progress has been the complexity of the processes that describe ozone formation. Highly sophisticated computer models of chemistry and transport have, up to now, been the only means to study the impact of abatement strategies. An alternative approach has been adopted here involving the development of a simplified long range transport model for ozone based on the analysis of over 60 experimental runs of a photochemical trajectory model applied to a wide range of hydrocarbon-nitrogen oxide emission combinations. Using the ozone-precursor relationship obtained, it has been possible to examine various policy options in the European context. Although taken together, three illustrative emission control scenarios reduce NO(x) and hydrocarbon emissions substantially through controls on motor vehicle exhaust, large combustion plant and solvent usage, a significant potential for photochemical ozone formation and long range transport may still remain after their implementation. The extents of precursor emission abatement that will be required, if the potential for ozone formation is to be reduced below published air quality criteria guidelines or critical levels, have been determined for each European country. The implied reductions in NO(x) and hydrocarbons relative to current levels amount to between 50 and 90%.

Journal Article↗