Seasonal occurrence and degradation of 2-methylisoborneol in water supply reservoirs.

摘要: Methylisoborneol (MIB) and geosmin are cyanobacterial metabolites that occur at nanograms per liter levels in surface water supplies responsible for many taste odor complaints about the aesthetics of drinking water. This study evaluated three supply reservoirs with bottom-release (hypolimnion) outlet structures Arizona. MIB concentrations were always higher than concentrations, but both followed similar seasonal trends. increased from spring to late summer, stratified vertically depth column; highest upper 10 m column. Thermal destratification autumn released impacted downstream utilities several months. By winter each year non-detectable. Mass balance analyses on indicated in-reservoir reactions more important changing conservative hydraulic "flushing" reservoir. Maximum net loss rates field (R(F,max)) order 0.23-1.7 ng/L-day, biodegradation appeared volatilization, photolysis or adsorption. Using lake laboratory experiments, bacterial (R(L)) ranged 0.5-1 ng/L-day comparable R(F,max) values. Based upon these rates, a reservoir would decrease by approximately 30 ng/L over period 1 month. was magnitude change commonly observed after thermal reservoirs.