Respiratory exposure to chemicals or agrochemicals poses potential risk to human health, especially to workers handling these products. Whether preparing a solution, dusting or spraying crops, or cleaning equipment, opportunities for inadvertent inhalation is a risk that can potentially lead to toxic effects, both acute and chronic. That's why identifying potential risk posed by respiratory exposure to a chemical or agrochemical is a mandatory component of toxicology studies in regulatory submissions for new registrations and, often, for re-registrations. In addition to the requirement, inhalation studies themselves are complex and challenging, as delivery of test articles via the inhalation route requires careful attention to substance aerosolization and particle size as well as constant control and monitoring over a prolonged time.