Unpleasant odor in drinking water is a worldwide substantial issue for consumers and water utilities. However, its hidden social impact has been ignored as there are no apparent direct health effects compared with other pollutants. In this study, we developed a method to characterize the adverse effects of a typical odorant based on behavioral responses with the corresponding economic burden, illustrated by 2-methylisoborneol (2-MIB). The dose-response based on behavioral responses to odors using a questionnaire was established in consideration of the bandwagon effect. Results showed that about half of consumers adopted averting behaviors after detecting even very weak odor (but generally recognizable) in drinking water. Total economic burden was determined to be 290690 ± 27427 ¥ per million people per day by the surcharges arising from consumer averting behavior or additional treatment of drinking water odor, among which about 13% of surcharge originated from insensitive people because of bandwagon effect. This is the first study to quantify odor hidden risk based on people's behavioral responses using economic burden, which provides a useful tool to comparing the risks of different types of pollutants in drinking water.