On September 26, 2019, a fire took place in the Lubrizol factory in Rouen, exposing the population to inhalation of many volatile toxic agents, including carbon monoxide or other toxic agents secondary to combustion. It has been previously demonstrated that long-term exposure to ambient air pollution is associated with increased incidence of coronary events.

The objective of this study was to assess the impact of the Lubrizol factory fire on the incidence of coronary events.

All of the coronary angiograms performed in Rouen and Le Havre, from 05/01/2019 to 12/31/2019 were collected from the prospective FRANCE-PCI registry. The number of coronary events over time was analyzed in Rouen and in a region not exposed to fire (Le Havre). To study the impact of the fire on coronary events, a before/after fire and here/elsewhere analysis was carried out. Home postal codes of patients were also captured, which made it possible to specify the analysis in the Rouen region according to the fallout from the smoke plume.

A significant increase in overall coronary syndromes was observed in Rouen after the fire [67.5 (63.2;78.5) events per week after vs. 61.5 (58;64) before, P=0.03]. The increase in events mainly concerned acute coronary syndromes [41.0 (39;45.75) events per week after vs. 37.0 (32.5;44.5) before, P=0.09] and the peak of occurrence was observed one month after the fire. In contrast, there was no significant variation in Le Havre [33.0 (27.0;36.5) events per week after vs. 30.0 (25.0;33.5) before; P=0.28]. Interestingly, through analysis of postal codes, we were able to demonstrate that the increase in coronary events in Rouen was greater in the most exposed areas (Fig. 1).

Our results suggest a delayed increase in coronary events, especially acute ones, after the Lubrizol factory fire in Rouen. Further studies are needed to assess the long-term effect and verify the absence of potential confounding factors.