How many days does mouse poison remain effective? - briefly
Most rodent baits retain their toxicity for roughly two to three weeks, though peak effectiveness is typically observed during the first ten to fourteen days after placement. After that period, potency declines and the poison may no longer attract or kill mice reliably.
How many days does mouse poison remain effective? - in detail
The effectiveness of rodent anticoagulant baits typically persists for a limited period after placement. Most first‑generation compounds (e.g., warfarin, chlorophacinone) retain lethal potency for 3–5 days under indoor conditions. Second‑generation agents (e.g., brodifacoum, difethialone) remain active longer, often 7–14 days, because of higher potency and slower degradation.
Key factors influencing the active lifespan include:
- Temperature: Warm environments accelerate chemical breakdown; in temperatures above 25 °C, potency can drop by 20 % each day. Cooler settings (10–15 °C) extend activity by up to 50 %.
- Humidity: High moisture levels promote hydrolysis, reducing effectiveness within 2–3 days. Dry air preserves the bait for the full advertised period.
- Exposure to light: Direct sunlight degrades many anticoagulants within 24–48 hours; storage in opaque containers prevents this loss.
- Food competition: Presence of abundant alternative food sources can diminish bait consumption, effectively shortening the window of impact.
- Formulation: Pelleted baits with protective coating last longer than loose granules, which are more susceptible to environmental wear.
Regulatory guidelines often require that bait be removed or replaced after the maximum efficacy interval to avoid non‑target exposure. For indoor infestations, a replacement schedule of every 7 days for second‑generation products and every 4 days for first‑generation products is considered best practice. In outdoor settings, the schedule should be adjusted upward by 2–3 days to account for accelerated degradation from rain and UV radiation.
Monitoring should continue for at least one week after the last application to confirm mortality. If no reduction in rodent activity is observed, re‑evaluation of bait type, placement density, and environmental conditions is warranted.