Abstract
Previous studies have linked formaldehyde (FA) fumigation to significant risks to animal health, highlighting, among other effects, its cytotoxic and genotoxic potential. Literature includes several studies on the use of FA for fumigating hatching eggs, but studies employing in-depth methodological approaches are scarce. As a result, the effects of practices involving this chemical remain insufficiently characterized. The present study aimed to investigate the antibacterial effects and potential toxicity resulting from the fumigation of hatching eggs with FA. The three FA concentrations (2.5, 5, and 10 g/m(3)) exhibit effective antibacterial activity, but this effect does not translate into long-term benefits. FA affected hatchability and demonstrated embryotoxic effects, with repercussions on chicks depending on the concentration used. The overall quality of poultry and the losses from eggs fumigated with FA remain questionable. Despite its efficacy as an egg fumigant, the observed toxicity suggests that its use violates safety standards and should be reconsidered. If its use cannot be avoided, the lowest possible concentrations should be prioritized to minimize toxic effects.