Under US laws, pesticide misuse is the use of a pesticide in such a way as to violate pesticide laws, or to endanger humans or the environment. The most common example of pesticide misuse is application inconsistant with the labeling, which could be use of a material in any way not described on the label, changing dosage rates, or violating a specific safety instruction.
Other kinds of pesticide misuse could include selling or using an unregistered pesticide, or one whose registration has been revoked, the sale or use of an adulterated or misbranded pesticide. It would also be a violation to alter or remove pesticide labels, to sell restricted pesticides to an uncertified applicator, or to fail to keep sales and use records of restricted pesticides.
One of the worst cases of pesticide misuse in recent history involved the application of a pesticide intended for outdoor agricultural use (methyl parathion) to homes in Mississippi for cockroaches and other home pests. Two exterminators were charged with multiple criminal charges after their ongoing use (of several years) was exposed. A number of residents, including two infants, suffered symptoms of pesticide poisoning. A number of homes and business, including several day care centers and schools were rendered uninhabitable or unusable. Heavy fines and prison terms followed for the perpetrators.
Pesticide misuse that endanger human health or even cause death get the most attention from law enforcement, yet pesticide poisonings are still a common problem, particularly with agricultural workers.
Pesticide misuse can also endanger wildlife and other environmental resources. A Florida man was recently cited and fined $23,100 for using the pesticide aldecarb on deer carcasses to kill coyotes, for storing the pesticide in unlabeled containers, and not being a certified applicator.
Specific label directions are given on materials that are toxic to bees, because these pollinators are considered an important environmental resource. A typical bee-protection label direction reads: "This product is highly toxic to bees exposed to direct treatment on blooming crops or weeds. Do not apply this product or allow it to drift to blooming crops or weeds if bees are visiting the treatment area."
A South Carolina farmer was cited and fined for pesticide misuse, because he ignored the above directions, and sprayed a blooming cucumber field while bees were foraging on the blossoms, causing a serious bee kill. Similar bee kills have cost US beekeepers and the growers who need bees for pollination billions of dollars in losses.
Pesticides are toxic compounds and the labels are specifically designed to make their use effective and safe. Ignoring the directions can lead to civil and criminal charges and civil liablity for damages to other parties.