Identification of alkyl-methoxypyrazines as the malodorous compounds in water supplies from Northwest Spain.
A study of organic compounds which caused several odor problems in water supplies from NW Spain was carried out. Sour dish-cloths, potato bin and musty were the main descriptors associated with these events. Closed loop stripping analysis combined with sensory-GC and GC/MS detection was used. The compound producing the initial odor event was 3,5-dimethyl-2-methoxypyrazine, identified for the first time as the compound responsible for odor incidents in finished water. Concentration levels were up to 300 ng/L in the effluent from an activated sludge wastewater treatment plant (WWTP) and 3 ng/L in finished water. 3-isobutyl-2-methoxypyrazine and other alkyl methoxypyrazines were the compounds responsible for the odor events that occurred several months later. Concentration levels in the mg/L range were measured in the activated sludge of a WWTP.
Ventura
Francesc
F
Aigües de Barcelona, Barcelona, Spain. fventura@agbar.es
Quintana
Jordi
J
Gómez
Mariano
M
Velo-Cid
Mónica
M
D004784:Environmental Monitoring; D008401:Gas Chromatography-Mass Spectrometry; D009812:Odorants / Q000032:analysis*; D011719:Pyrazines / Q000302:isolation & purification*; D013030:Spain; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D014881:Water Supply / Q000032:analysis*
C553386:3,5-dimethyl-2-methoxypyrazine; D011719:Pyrazines; D014874:Water Pollutants, Chemical; C034376:2-isobutyl-3-methoxypyrazine