Rear Seat Belt Corrosion!

Hi folks. I was cleaning my 2017 and I noticed on all three backseat seat belt buckle connectors, there's this white-ish, light colored flaky shit. It crumbles when I try to get it off, and doesn't come off easily. See pics. Just wonder what the hell is this stuff?? Is it normal?
These are the buckle connectors underneath the rear backseats. I bought my car brand new in 2017, so this is definitely not a flood car, and I don't see corrosion anywhere else in the interior. I noticed this a few months ago and hadn't gotten around to posting it here until now. Please advise.

 

Taste it.

 

Yeah, taste it....

 

OK edge lord. Thanks. Tastes like banana.

 

Looks like white rust. Vinegar will get it off.

 

Something you spilled back in 2018?

 

I mean it. Looks like salt crystals or something. Not rust.

 

I haven't spilled anything in this car though. Nobody rides in the backseat either.

 

Ever shampoo back there?

 

Taste it. Tis the TW way.















Taste at your own risk.

 

Any leaks from the 3rd brake light?

 

For a little context about tasting it for people who have not seen it.


https://www.tacomaworld.com/threads/salt-seeping-up-through-floor.602010/

 

So the general consensus is that this is probably rust and not normal? I don't have water damage anywhere else in the car. It's weird.

 

I'd definitely say that isn't rust. But I'm also not sure what kind of metal that is. If it is aluminim, aluminum corrodes, but it doesn't affect the structural integrity like rust does. But I'm not sure what would be causing that.

 

Moisture leakage from underneath. Remove bolt, clean, put lots of silicon.

 

Those brackets are zinc-coated steel. Double-check if your third brake light is leaking.
Where do you live?

 

Some capillary action and galvanic corrosion

 

100% that is the zinc corroding. Can be a leak or it could just be wet stuff in the back making the carpet wet.

Clean it with a scouring brush and vinegar.

Coat it with clear coat or paint or silicone or whatever.

Monitor your zinc coated parts every six months or so.

 

Do you live in a disgustingly humid region, OP?

 

Salt water will do that.