I don't want mice in this daycare, I do not want them anywhere.

November 13, 2023 9:24 AM

My toddler's daycare has a mouse issue. A pest control company is coming in. Should we be concerned about the toddlers' exposure to rodenticide chemicals?

I'm assuming it's Orkin using bait stations with brodifacoum and warfrin, although I've scoured the website and called the company and been passed around to five different departments with no firm answer on what the bait will be in this application.

I'm sure the bait stations are meant to be tamper-proof, but I'm imagining poison-dusted mice wandering around and dragging out little bits of poisoned bait for the toddlers to discover. There are also toddlers with severe food allergies in the class, so I'm curious what other foods might be in the bait (for instance, we bought some ant baits last year and I was surprised to discover they were stuffed with peanut butter).

I'm squicked about hantavirus, and uncomfortable about my child being exposed to rodenticides. Overall, I'm pretty horrified by the whole thing.

Can anyone share clarity: What chemicals are likely used? What are the odds the toddlers will be in contact with those chemicals? What should we do?
Thanks for any advice.

posted by nouvelle-personne to Science & Nature (7 answers total)

Call the daycare and ask what methods they'll be using? I've had a couple rodent issues out in my shop, and I've always preferred traps over poison. With poison, you never know where the critters will go off and die, and then you have a decomposing rodent issue... somewhere. With traps (and there are all sorts, including live/humane, and those that are as safe as possible around toddlers), you know exactly where the rodents will wind up. A good pest control company will have many tools at their disposal, and will recommend an approach that is appropriate for the environment.

Again, a good pest control company will include this as part of a comprehensive sevice, but eliminating the mice is only half the battle; steps should also be taken to close up the points of ingress, and eliminate whatever attracted them in the first place.
posted by xedrik at 9:45 AM on November 13, 2023 [2 favorites]

There are bait station baits available whose only active ingredient is sodium chloride (i.e. common table salt). They work, though it does take more of the salty baits to kill a mouse than the warfarin ones. Salt baits also don't render the poisoned mice poisonous in their turn to creatures that might eat dead mice, such as pet cats and dogs or the local owls; rodents, it seems, are just particularly bad at dealing with excess salt. Also, because salt kills by dehydration, the mice it kills are somewhat more likely to mummify inside your walls than putrefy there.

If a toddler broke into a bait station full of salty pellets and chowed down, it would do them no more harm than eating a similar volume of e.g. salted pretzels (leaving aside the hantavirus question). For what it's worth, I've tasted these baits and they're not as nice as pretzels. The mice seem to disagree, though: I've never seen evidence of pellets being left around after removal from the bait stations.

On hantavirus: I would expect the risks to your toddlers, in an environment containing salted mouse bait stations whose contents the mice might scatter, to be lower than those involved in sharing the space with overnight uncontrolled unsalted mice and their possibly toddler-compelling shit pellets.

But yes, if the company is indeed proposing to bait with a more aggressive poison than salt, as a parent I would absolutely be kicking up a stink about that. A worse stink, even, than dead mice in the walls.
posted by flabdablet at 9:53 AM on November 13, 2023 [3 favorites]

yeah you need to ask what they're going to use, and advocate for trapping not poison. In my experience (residential) rodenticide is never used because then they crawl into your walls and die and the house becomes untenable because of the smell. (And as pointed out above, the bigger part of what you pay for is the expert examination of the premises to identify rodent egress points and block them.)
posted by fingersandtoes at 9:56 AM on November 13, 2023 [1 favorite]

These are the salt baits I have used successfully (and eaten small quantities of for testing purposes).
posted by flabdablet at 10:03 AM on November 13, 2023 [1 favorite]

I'm not sure about mice but for rats in my neighborhood, poison bait traps only go outside. Inside they use either snap traps or sticky traps, likely sticky traps in a daycare. But the #1 mitigation method is find where they are coming in and block it off so more don't come in.

Sticky traps have their own set of problems, I think electric zappers are the most humane and least traumatizing kind of trap. But those are pretty expensive.
posted by muddgirl at 10:22 AM on November 13, 2023

This goes a bit beyond what one can expect the day-care to do. In October, my adult daughters had mice in their city apartment: 'tis the season when outdoor rodents are looking for somewhere cosy for Winter. Daus were all for calling Rentokil but I persuaded them to save €n00 and buy some snap traps. Which they did; and solved the problem. You can buy ready-baited traps but using peanut-butter and oats works very well. I customize the bait tray by sewing on some hanks of thin string = thick thread which makes it all 'stickier' for both the PB&O and teeth.

Set your hantamind at ease! From CDC: In North America, only some kinds of mice and rats can give people hantaviruses. They are the deer mouse, the white-footed mouse, the rice rat, and the cotton rat. Other rodents, such as house mice, roof rats, and Norway rats, have never been known to give people HPS.
posted by BobTheScientist at 10:32 AM on November 13, 2023 [1 favorite]

I honestly wouldn't worry about this and would just be glad the daycare is actively dealing with the problem. In a situation with toddlers around, I think you just want to be rid of the mice as quickly as possible by whatever means necessary. And we, in NYC, and with toddler, have used both bait and glue traps in our old house when needed. The older kids (over the age of 5) are the only ones who take any interest in it. The toddler would much rather play with his toys. With respect to the poison traps, I'm pretty sure there's no way he could get his hands in it enough to open it and eat the baits. In any event, we keep them pretty well hidden . . .
posted by luckdragon at 6:59 PM on November 13, 2023