How long does mouse poison remain effective? - briefly
Most anticoagulant baits retain toxicity for about two to four weeks after being placed in a trap or bait station. Single‑dose formulations may stay lethal for up to six months if kept in sealed packaging.
How long does mouse poison remain effective? - in detail
Rodenticide potency depends on formulation, active ingredient, storage conditions, and target species. Most anticoagulant baits retain lethal activity for 12‑24 months when sealed in their original packaging and kept in a cool, dry place. First‑generation compounds such as warfarin lose effectiveness after about six months, while second‑generation agents like bromadiolone, brodifacoum, and difethialone remain potent for up to two years.
Key factors influencing shelf life:
- Packaging integrity – airtight containers prevent moisture ingress and oxidation.
- Temperature – exposure to heat accelerates degradation; ideal storage is 15‑25 °C.
- Humidity – high relative humidity promotes hydrolysis of the active compound.
- Light exposure – ultraviolet radiation can break down many anticoagulants.
Once a bait is opened, exposure to air and humidity reduces potency markedly. In practice, efficacy diminishes within 4‑8 weeks, and manufacturers typically recommend discarding any unused product after this period.
For non‑anticoagulant poisons (e.g., zinc phosphide, bromethalin), stability is shorter. Zinc phosphide reacts with moisture, losing toxicity after 3‑6 months. Bromethalin, a neurotoxin, remains active for 12‑18 months under proper storage but should be replaced after six months once the container is opened.
To maximize effectiveness:
- Store baits in original, sealed containers.
- Keep them in a temperature‑controlled, low‑humidity environment.
- Rotate stock: use older inventory first, replace after the indicated shelf‑life.
- Inspect for clumping, discoloration, or off‑odors before deployment; discard if any signs appear.
In summary, sealed anticoagulant baits can stay lethal for one to two years, whereas opened or improperly stored products lose potency within weeks to a few months. Non‑anticoagulant formulations generally have shorter usable periods and require stricter handling. Regular inventory checks and adherence to manufacturer guidelines ensure reliable rodent control.