It is now accepted as an article of faith that pure scientific recitation of difficult jargon and complex numbers is both useless and often inflammatory. With this I wholeheartedly agree. It is also recognized that paternalistic dismissals of people's concerns, i.e., by comparative risk analysis, is equally ineffective. As a physician, one who also happens to be trained in both toxicology and communication, I am duty-bound to answer these questions as honestly but also as definitively as I can. Before I tell you how I do this, let us analogize this to other health situations.
Informed consent is an essential part of medicine today.
We routinely help patients understand and weigh the risks and benefits of the things we recommend and the treatments we provide. Environmental risks are no different. If, for example, exposure levels to a known human carcinogen, e.g., benzene, were low or brief or both, it would be accurate and responsible to let concerned residents know that their risks, while not nonexistent, are extremely low. To do less, in the face of concerns and direct questions is, in my opinion, irresponsible. If risks are likely to be low, we owe it to the audience to say so.