PRINCIPLES OF TOXICOLOGY - Biology East Borneo

18.9 RISK COMMUNICATION 473TABLE 18.8 Examples of Risk Communication ProblemsSource of ProblemSource of the messageThe messageChannel for conveying themessageReceiver of the messageExamplesThe source of the risk information, usually a governmental or industrial entity orrepresentative, is not trustedAny disagreements among scientific experts make the information appear to beguessworkThere is often a reluctance to disclose limitations and uncertainties in the riskestimatesThe risk assessment may not address issues of greatest concern to individualsand communitiesRisk estimates may have large uncertainties due to limitations in models,methods, and data used in the risk assessmentThe inherent technical nature of risk assessments makes them difficult forlaypersons to understandUse of jargon and bureaucratic and legal language make risk assessments evenmore incomprehensibleMedia interpretation may result in presentation of oversimplified, distorted, orerroneous informationMedia emphasis on drama, wrongdoing, or conflicts clouds presentation of riskinformationEagerness by media to report may result in premature disclosures of scientificinformationPublic perceptions of risk are often inaccurateThere may be unrealistic demands for scientific certainty in risk estimatesThere is usually a lack of interest in the technical complexities of the riskassessment, and therefore a poor understanding of what risk estimatesrepresentNot everyone will be open-minded; some individuals with strong opinions andbeliefs will not be receptive to new informationThere is often an unwillingness or inability to view risks in context, understandrisk tradeoffs, or view risk problems from a perspective other than that of theirown perceived immediate interestsSource: Adapted from Cohrssen and Covello (1989).communication. Unfortunately, all too often, the answers conveyed by the risk assessment can seemambiguous. Scientists are trained to be circumspect in their conclusions and carefully point out anycaveats in their analysis. This certainly applies to risk assessments, where responsible presentation ofrisk estimates is always accompanied by a discussion of the many areas of uncertainty and limitationsin the analysis. When all of the caveats and uncertainties are presented along with the risk estimate,the uncertainty looms large and it is easy for the public to conclude that “They don’t really know whatthe risk is.” When this happens, regardless of whether the risk estimates themselves are large or small,they have little credibility. Thus, the dilemma for the risk communicator is how to adequately conveythe underlying uncertainties in the risk estimates without losing the essential message that the risksare large or small, as the case may be.Deciding whether a risk is acceptable requires, in part, placing that risk in context. Thus, the riskfrom a particular chemical or set of exposure circumstances must be compared with other risks to theindividual or population in order to place that risk in perspective. While this is straightforward inconcept, it is difficult in practice, particularly when communicating risk to the general public. Onereason is that the public, unaccustomed to seeing typical risk assessment outputs, may have little basisfor comparison. Unless someone has experience with, or is shown, comparative risk data for a varietyof hazards, it is difficult for them to know whether a 1 × 10 –5 risk is significant. For noncancer healtheffects, the meaning of outputs in terms of hazard index or margin of exposure is even more obscure.How, for example, would you help citizens place a hazard index of 3 for a chemical exposure in thecontext of risk from events in their everyday lives?