Dictionary: rodenticide   (rō-dĕn'tĭ-sīd')

A chemical substance used to kill rodents.

A toxic chemical that is used to kill pest rodents and sometimes other pest mammals, including moles, rabbits, and hares. Most rodenticides are used to control rats and house mice.

Rodenticides are generally combined with some rodent-preferred food item such as grain (corn, wheat, oats) or a combination of grains in low yet effective amounts. Bait formulations may be in pellet forms or incorporated in paraffin blocks of varying sizes. As a safeguard against accidental ingestion by nontarget species, baits are placed either where they are inaccessible to children, domestic animals, or wildlife, or within tamper-resistant bait boxes designed to exclude all but rodent-size animals.

As a group, anticoagulant rodenticides dominate the market and are sold under a wide variety of trade names. In order of their development, they are warfarin, pindone (Pival), diphacinone, and chlorophacinone. When small amounts of these anticoagulants are consumed over several days, death results from internal bleeding. The newer, second-generation anticoagulant rodenticides, such as brodifacoum, bromadiolone, and difethialone, were developed to counteract the growing genetic resistance in rats and house mice to the earlier anticoagulants, especially warfarin. The second-generation compounds are more potent and capable of being lethal following a single night's feeding, although death is generally delayed by several days. Rodenticides that do not belong to the anticoagulant group include zinc phosphide, bromethalin, and cholecalciferol (vitamin D₃). The feeding and lethal characteristics differ among them. Acutely toxic strychnine baits are also available but are restricted to underground application, primarily for pocket gophers and moles. Several lethal fumigants or materials that produce poisonous gases are used to kill rodents in burrows and within other confined areas such as unoccupied railway cars or buildings. Lethal fumigants include aluminum phosphide, carbon dioxide, chloropicrin, and smoke or gas cartridges, which are ignited to produce carbon monoxide and other asphyxiating gases.

Because of their high toxicity, rodenticides are inherently hazardous to people, domestic animals, and wildlife. They are highly regulated, as are certain other types of pesticides. Some rodenticides can be purchased and used only by trained certified or licensed pest control operators, while others with a greater safety margin can be used by the general public. All rodenticides must be used in accordance with the label directions and may be prohibited where they may jeopardize certain endangered species. See also Pesticide; Rodentia.

A chemical substance used to kill rodents.

1. destructive to rodents.
2. an agent destructive to rodents. They are all toxic to animals and are a common cause of poisoning. The common ones are warfarin and its related compounds and sodium fluoroacetate, called also compound 1080. Other agents are cyanide, alphanaphthylthiourea (ANTU), thallium salts and zinc phosphide. Although these substances are selected because of their relatively low toxicity for domestic animals, they can all cause severe losses in them if used carelessly.