What can be used to poison rats? - briefly
Common rodenticides include anticoagulant baits such as warfarin, bromadiolone, and difenacoum, along with acute toxins like zinc phosphide and bromethalin. These compounds are typically delivered in tamper‑resistant stations to target rats while reducing risk to non‑target species.
What can be used to poison rats? - in detail
Substances employed to kill rats fall into several chemical classes, each with distinct mechanisms and regulatory considerations.
Anticoagulant rodenticides interrupt blood clotting by inhibiting vitamin K epoxide reductase. First‑generation compounds such as warfarin and chlorophacinone require multiple feedings; second‑generation agents like bromadiolone, difenacoum, and brodifacoum act after a single dose and remain active in the liver for weeks, increasing risk of secondary poisoning.
Neurotoxic agents disrupt nerve function. Bromethalin interferes with mitochondrial oxidative phosphorylation, causing cerebral edema. Zinc phosphide releases phosphine gas when it contacts stomach acid; the gas interferes with cellular respiration. Sodium fluoroacetate (1080) blocks the citric acid cycle, leading to rapid systemic failure.
Hypercalcemic agents elevate blood calcium levels, causing cardiac arrhythmia and renal failure. Cholecalciferol (vitamin D₃) induces hypercalcemia after ingestion of a single dose.
Metal-based poisons include strychnine, which blocks inhibitory neurotransmission, and copper sulfate, which causes gastrointestinal irritation and hemolysis at high concentrations.
Application methods vary according to environment and target population. Bait stations conceal anticoagulant or neurotoxic granules, limiting access by non‑target species. Broadcast grain baits distribute pellets over fields, suitable for outdoor infestations. Dust formulations can be applied in burrows or crevices, delivering metal phosphides directly to nesting sites. Pre‑bated traps combine mechanical capture with a lethal dose of poison, allowing immediate removal of the carcass.
Dosage recommendations are expressed in milligrams of active ingredient per kilogram of body weight. For anticoagulants, a single dose of 0.02–0.05 mg/kg of bromadiolone typically achieves mortality within 3–5 days. Bromethalin requires 2–5 mg/kg for lethal effect. Zinc phosphide is effective at 2–4 mg/kg of phosphine released. Cholecalciferol causes death at 0.5–1 mg/kg of vitamin D₃.
Regulatory frameworks restrict the availability of highly toxic compounds. Many jurisdictions require licensed applicators for second‑generation anticoagulants, metal phosphides, and sodium fluoroacetate. Documentation of bait placement, target species, and disposal of dead rodents is often mandated to mitigate environmental impact.
Safety protocols include wearing protective gloves, using sealed bait containers, and storing poisons away from food sources. Immediate decontamination of skin and eyes, as well as proper ventilation when handling phosphide powders, reduce occupational exposure. Disposal of carcasses should follow local guidelines to prevent secondary ingestion by scavengers.
Selecting an appropriate lethal agent demands assessment of infestation severity, non‑target risk, and legal constraints. Anticoagulants suit indoor or low‑density populations where prolonged exposure is acceptable. Neurotoxic and metal phosphide formulations address high‑density outdoor infestations but require stricter containment measures. Hypercalcemic agents provide an alternative where resistance to anticoagulants has emerged.