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Practical Application of Ozone: Principles and Case Studies
Published in Bruno Langlais, David A. Reckhow, Deborah R. Brink, Ozone in Water Treatment, 2019
Guy Bablon, William D. Bellamy, Gilles Billen, Marie-Marguerite Bourbigot, F. Bernard Daniel, Françoise Erb, Cyril Gomella, Gilbert Gordon, Phillippe Hartemann, Jean-Claude Joret, William R. Knocke, Bruno Langlais, Alain Laplanche, Bernard Legube, Benjamin Lykins, Guy Martin, Nathalie Martin, Antoine Montiel, Marie Françoise Morin, Richard S. Miltner, Daniel Perrine, Michele Prévost, David A. Reckhow, Pierre Servais, Philip C. Singer, Otis J. Sproul, Claire Ventresque
The compounds most frequently associated with tastes and odors from these microorganisms are the alicyclic alcohols, geosmin and 2-methylisoborneol (MIB). Numerous studies that identify these metabolites have been reported in the literature (Gerber 1979; Wood et al. 1983; Medsker et al. 1968). However, geosmin and MIB are not the only products that cause tastes; numerous compounds are formed and released by different types of algae (Hayes and Burch 1989). These products are varied (Jüttner 1983), and include phenols, aliphatic alcohols (saturated or nonsaturated), aldehydes, aromatics, ketones, alkanes, esters, thioesters, and sulfides. They are responsible for tastes either in their natural form (Palmer 1962) or after being exposed to oxidative treatment such as chlorination (Burttschell et al. 1959). Two compounds that have strong characteristic odors in their natural form are cadine-4-ene-l-ol (Gerber 1971) and 2-isopropyl-3-methoxy-pyrazine (Buttery and Ling 1973).
Detection of Actinomycetes
Published in Maria Csuros, Csaba Csuros, Klara Ver, Microbiological Examination of Water and Wastewater, 2018
Maria Csuros, Csaba Csuros, Klara Ver
Actinomycetes are responsible for the earthy musty odors that affect the quality and public acceptance of municipal water supplies in many parts of the world. They are among the naturally occurring odors that plant operators find the most difficult to remove by conventional treatment. It was assumed that these odors could be attributed to volatile metabolites formed during normal Actinomycete development. Two such compounds, geosmin and 2-methylisoborneol, have been isolated and identified as the agents responsible for earthy-musty odor problems. Geosmin and 2-methylisoborneol have threshold odor concentrations well below the µg per 1 concentration. Thus, traces of these products are sufficient to impart a disagreeable odor to water, soil, sediment, and give a muddy flavor to the fish.
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Published in Jamie Bartram, Rachel Baum, Peter A. Coclanis, David M. Gute, David Kay, Stéphanie McFadyen, Katherine Pond, William Robertson, Michael J. Rouse, Routledge Handbook of Water and Health, 2015
Cyanobacterial blooms can cause numerous issues that: (1) impede recreation (e.g. offensive odors, reduced water clarity); (2) limit its use for drinking water (i.e. production of non-toxic odorous substances geosmin, 2-methylisoborneol and β-cyclocitral impart taste and odor to finished drinking water); and (3) threaten natural aquatic biota like sport fish (i.e. decay of cyanobacterial blooms can lead to increasing ammonia concentrations and depletion of dissolved oxygen) (Paerl, 1988; Kenefick et al., 1992). However, it is the production of potent hepato- (liver) and neuro-toxins by several species and strains of cyanobacteria that present the greatest potential risk to humans and domestic and wild animals. The community composition – abundance and growth stage of various species and strains – of cyanobacteria plays a key role in determining the type and concentrations of toxins present at a given time. Cyanobacteria communities and hence blooms are both temporally and spatially dynamic; and they can be complex (i.e. comprising many species) or quite simple (i.e. dominated by one or two species). Notably, toxins are often present at varying concentrations in water prior to the formation of surface blooms and while some blooms can be extremely toxic possessing high concentrations of several toxins simultaneously, other blooms may contain trace levels or even none at all.
Advanced Water Treatment System of the Bureau of Waterworks, Tokyo Metropolitan Government
Published in Ozone: Science & Engineering, 2019
The concentration of 2-methylisoborneol (2-MIB) a compound responsible for musty odor increased in raw water in summer since it was effected by blue-green algae breeding the tributary of water intake spot upper 2.5 km. The annual maximum concentration of 2-MIB in raw water were 140, 110, and 340 ng/L, in 1992, 1993, and 1994, respectively. However, the 2-MIB was completely removed by the advanced water treatment at Kanamachi WTP. It was found that 2-MIB was removed by coagulation-sedimentation process (14%), ozonation (70%), and BAC (16%). While the maximum concentration of 2-MIB after sedimentation was 190 ng/L, it was reduced to 18 ng/L by ozonation (applied ozone dose: 3 mg/L) and completely removed by BAC.