What caused this on door sill protector rubber?

^^^ This^^^
The DEET in bug repellent definitely destroys plastic in short order. I lost a watch-band and it marred the bezel on a nice Casio GShock watch just from lightly spraying my arms before setting out on a hike. It works well: but at a price. You can buy the "Kid's Formula" which does't contain it, but it doesn't do as good a job: especially with Ticks.

 

This is what I used, I assume most will do same damage whenever its like 105 out there, especially in a car even with windshield sun shade

 

Hadn't heard of this one before.

I assume this is a very close companion to Permethrin. An insecticide the military uses on its issued clothing.

I’ll look it up later to be sure.

 

It's the DEET, labeled in the active ingredients... it is not temperature dependent. Keep it off your plastics.

 

It's also worth noting, the door sill protectors are relatively cheap. I'd peel up the existing melted cover, clean and paint the metal below (as needed), and apply a new door sill protector.

https://parts.elmhursttoyota.com/oe...S0CdB92aWclcxS-sMPBQdHsn6GDTUXNzWQZQFP2AtPZPp

(Confirm fitment)

 

Metal below is already painted. However the sill seems to be glued on pretty hard, so not sure how can I peel up majority of it, its like one piece. I will see what I can do, its sad because it says Tacoma there on the sill...

 

Can you neutralize it somehow to stop the spread?

 

I've never had a tick while using it. Can't say if that's luck or not, but it sure holds off the skeeters and no see ums