In response to the increasing number of reports regarding unusual health events occurring in the workplace, Santé publique France has established a regionalized system known as the Occupational Health Alert Groups (GAST). The goal is to organize a rapid and appropriate regional response to these reports from the workplace, which are often prompted by suspected clusters of cancer or the occurrence of an unexplained collective syndrome.

By mobilizing multidisciplinary and complementary expertise through the Regional Intervention Units (CIREs), this occupational health surveillance and alert system proves its value and effectiveness when called upon by frontline professionals, foremost among whom are physicians and, more broadly, occupational health services. The team in charge of the system therefore sought to create an informational resource to raise awareness among these professionals and to coordinate the network of existing GAST members and CIREs. The goal is to expand the GAST system and promote a culture of reporting in occupational health.

While Occupational Health Alert Groups (GAST) are now established in 11 regions, the activity report for this system, led by Santé publique France, shows a steady increase in reports of unusual health events in the workplace. These are mostly unexplained collective syndromes, also known as sick building syndrome. When these non-infectious “outbreaks” of varied symptoms spread among the staff of a public institution or a company, they often pose challenges for the occupational physician: how to objectively assess the reality of the collective phenomenon, how to investigate its cause, and how to manage relations with staff, management, and the Health, Safety, and Working Conditions Committee (CHSCT)? The same methodological challenges arise when an excess of cancer cases—or cases of any other disease—is suspected among staff. Is the number of cases reported to the physician “normal” for the size of the company? Moreover, is this truly the actual number of cases? What are the known risk factors for this disease? Are those affected occupationally exposed to one or more of these risk factors? It is precisely to define and manage the investigation of such unusual health events that the Gast system was created, equipping each regional group with occupational risk specialists from various disciplines