Dusts are usually less hazardous to people than sprays because:

Dusts are generally considered less hazardous to people than sprays primarily because they are not as easily absorbed through the skin. The physical properties of dusts, combined with their larger particle sizes, diminish the potential for skin absorption compared to liquid formulations like sprays, which can penetrate the skin readily. This reduces the likelihood of systemic toxicity from dust applications.

In addition to this, dusts tend to adhere to treated surfaces and have less volatility compared to liquid sprays, which may evaporate and become airborne more easily, increasing the risk of inhalation exposure. Therefore, it is accurate to note that the reduced absorption through the skin is a significant factor in evaluating the safety of using dust formulations in pest control.