Public anxiety of near panic proportions was created by the announcement of a plan to commence aerial application of malathion bait over a large urban area in California for the eradication of the Mediterranean fruit fly within four days. A risk assessment had reported the project entailed no significant risk to health but environmentalist groups and the media ignored the report. We describe the successful measures taken by State health workers to counteract the anxiety which itself constituted a serious public health problem. The most important measure was the rapid convening of a Health Advisory Committee composed of recognized experts and local professionals and leaders to provide an authoritative, respected and sympathetic voice to deal with the community's concerns. These experiences may be of value to other communities facing unwarranted anxiety over perceived environmental hazards.