Residents' Responses to the May 1-4 2010 Boston Water Contamination Incident

This study used the Protective Action Decision Model to examine local residents’ warning sources, warning receipt times, message content, warning confirmation, risk perception, and consumption of untreated tap water, boiled water, bottled water, and personally chlorinated water during the May 1-4 2010 Boston water contamination incident. Most residents received warnings from news media and peers and these warnings mentioned 2.3 of five recommended elements of a warning message—most commonly the threat and the recommended protective action. Consumption of untreated tap water declined, consumption of personally chlorinated water remained negligible, and consumption of boiled water and bottled water increased. First warning source was significantly related to protective response but message content was not. Unexpectedly, risk perception was more strongly related to water consumption before the incident than after the incident. This finding calls attention to the need to recognize that, although increased risk perception can increase protective action, successful implementation of protective actions can decrease risk perception.