Mold detection and cleaning in somewhat unusual places

I discovered in recent years that my older car has a mild issue: if I open the trunk all the way, any rain water on it can drip off the corners of the lid and into my trunk. I thought this was just an annoyance at first.

But then this past winter, I found that a roll of paper towels and toilet paper I had in the trunk for emergencies were covered in black mold. I tossed them immediately, but also found that a beach chair and its bag, which I also had in the trunk, had all sorts of specks of mold.

With spring weather, I’ve tried and failed to clean the chair and bag with household cleaner and a toothbrush. Any suggestions on what else to try? It’s a cheap chair, so I could just toss it if using it is dangerous.

I didn’t see any other mold in the trunk, but I’m going to look again. How likely is it that a few objects being moldy didn’t spread it somewhere? I read that it can threaten my health to the extent of totaling the car and that the mold could spread to my house as well. (I don’t think I’ve been sick in a related way, but obviously not certain.) I didn’t wear a mask while trying to clean the chair in my living room either.

Clean freaks encouraged to give advice. Thanks in advance!

There dedicated mold cleaners.
Personally, since you could toss it, I’d go with bleach. Take it out doors.
Dilute bleach by 1/2 with water. Scrub. Masked, and wearing gloves. Rinse well. Away from your walk way or grass. If you have to, use a tarp.
Sun dry. As long as you can. The fabric or material will fade. Alot. Repeat if necessary. May take a few times.

That may not remove the ugliness. Mold leaves a stain. Hydrogen peroxide might remove the stain. Dilute and let it sit on it. Rinse.

That’s way too concentrated. The CDC recommends

Use a bleach solution of no more than 1 cup (8 ounces) household laundry bleach per 1 gallon of water to kill mold on surfaces

I’d use a non-bleach mold killer. You can find them in Home Depot or other such stores.

Eh, I’d toss the chair and focus on the carpet and liner of the trunk instead. You might be able to get it professionally steam cleaned, maybe, or it might be more cost effective to have it all replaced, you’d have to research that.

If anyone is interested - I’ve had a decades-long fight against mold in my basement. The best product I’ve used is this stuff, whose active ingredientis sodium carbonate, aka washing soda. Better than bleach, doesn’t stink, long-lasting.