As of mid-September 2026, here in Riverside, I’m back to lying awake listening for scratching over the ceiling of my old ranch house. For years my answer was a box of bait blocks: toss a few into the attic, a few more along the foundation, and call it handled. Out of sight, out of mind, no traps to empty.
Riverside County’s own vector control guide took that apart for me. Its rodent pamphlet says snap traps “are inexpensive, give positive results, and eliminate the possibility of a poisoned rodent dying in an inaccessible area, creating serious odor problems.” In a house like mine, the attic and the wall cavities are exactly that kind of inaccessible area.
What the EPA says
The EPA’s rodenticide page is plain about where the strongest bait went: second-generation anticoagulant rodenticides “no longer are registered for use in products geared toward consumers and are registered only for the commercial pest control and structural pest control markets.” California’s law on the same poisons prohibits their use statewide until the state pesticide director certifies that specified measures have been taken to evaluate and restrict them and only use them when necessary.
The regulators pulled them because of what happens after the rodent eats.
Why the bait doesn’t end it cleanly
A poisoned rodent doesn’t drop on the spot. The EPA says deaths typically occur between four days and two weeks after rodents begin to feed on the bait. Because time-to-death is several days, rodents can feed multiple times before death, leaving carcasses with residues that may be many times the lethal dose. That’s days in which a poisoned animal is still alive somewhere in the house…