How long does rat poison remain effective? - briefly
Under typical storage, anticoagulant pellets stay toxic for roughly two to four weeks. Certain long‑acting formulations may remain effective for up to six months when kept dry and sealed.
How long does rat poison remain effective? - in detail
The effectiveness of rodenticide depends on the active ingredient, formulation, and environmental exposure. Anticoagulant compounds such as brodifacoum, bromadiolone, and difenacoum retain lethal potency for weeks after a single ingestion. The toxic effect may manifest up to five days post‑consumption, while secondary poisoning risk for predators can persist for 30 days or more. Non‑anticoagulant agents, including zinc phosphide and strychnine, degrade rapidly; activity usually diminishes within hours to a few days when exposed to moisture or sunlight.
Storage conditions strongly influence residual activity. Sealed, dry containers protect the bait, allowing the label‑specified shelf life—typically 24 months—to be achieved. Once the product is opened, humidity and temperature fluctuations accelerate degradation; potency often falls below effective levels after 4–6 weeks.
Key factors determining the persistence of rodenticide efficacy:
- Chemical class (anticoagulant vs. non‑anticoagulant)
- Formulation type (gel, block, pellet)
- Environmental exposure (rain, heat, UV light)
- Dosage and bait consumption rate
- Regulatory shelf‑life specifications
Understanding these variables enables accurate prediction of how long a given rodenticide remains potent in field conditions.