Communication of Risk due to Community and Workplace Petroleum Exposure

We report on experiences in communicating the results of the Valdez Air Health Study (VAHS), which evaluated health risks to residents of Valdez, Alaska from operation of the Valdez marine terminal of the Trans-Alaska Pipeline System, and in communicating the results of a subsequent study of terminal workers. The focus was the risk of leukemia due to benzene. Commu nication of the findings was primarily by the external scientists who did the study. They publicly described in Valdez the goals and design before and dur ing the study, as well as after the results were available. Key to all communica tion efforts was recognition and respect for the validity of local concerns and for the special interests of the population. A new and unique ingredient to the process was coordination with, and peer review by, a well-funded ($2.25 mil lion/year) citizens' oversight group. New information was always released first to the Valdez City Council. Basic information about cancer and risk was giv en. Comparisons with dissimilar risks were generally avoided, but information was given about other sources of benzene and the levels of benzene elsewhere. Public concern about persistent chemicals and ecological effects led to discus sion of these issues. The consultants were encouraged to present the VAHS to government scientists and at scientific meetings. Following the release of the VAHS data, concerns were raised about the benzene risk to the 300 employees at the terminal. A detailed evaluation was made of this risk which brought into contrast the different communication challenges posed by a community risk assessment aimed at reporting actual risk levels, and the workplace in which the focus is on keeping exposures below an accepted standard.