Maybe soaking with borax (20 Mule Team brand) would help. You could try something like Febreze, but be aware you're only putting perfume on top of the chemical smell. Chances are good that odor is permanent. Can you return the jeans before you wash them? Seriously, that is what I would do because I'm very sensitive to chemical smells. Washing never helped me.

I once bought a knit top, from Target, that had a terrible chemical smell. I washed it a few times, with everything in my laundry stash, and I finally sent it on to GoodWill before I ever wore it.

This also happened with black fabric I bought at a store. After multiple washings, it still smelled awful. I didn't sew it up and threw it out, instead.

Now I smell everything before I buy it. Some dye odors are just too awful to be around and can make us sick.

Try washing them and adding just plain old baking soda, it's great for getting out stubborn odors. You can buy a huge box of it on the detergent aisle. I add it to every load of bath towels...

Clothing is treated with insecticides, fungicides, etc. A few washes will take it out usually. Extra detergent, no fabric softner or dryer sheets so you're not recoating the fabric. Best of luck.

Both my daughter and I have had black jeans with the same problem. Many washings - it never went away.

I know that's not very helpful. Sorry.

Same here: black jeans from old navy. Seemed to have a musty wool smell to them, even after washing. Black dye?

There are some black dyes that put off a really bad odor. When I tossed the above-mentioned fabric, I did a Google search on the topic and found a lot about black dyes and odors.

Well, I have washed them 6 times and they still smell. Hot water, extra soap, etc. They are dark indigo Jag jeans from Amazon and I may try to return them. Smell has abated quite a bit, but if they are put in a closed room, the whole room will smell the next day.

Some sheets we got from a major mail-order retailer had a chemical smell that I couldn't wash out. We ended up returning them. A smell lingered in the washing machine for a few weeks, but it didn't transfer to any other laundered items.

Send them back.

Have you tried soaking them in a strong vinegar water solution or maybe even salt water?

May or may not help. I know both are supposed to help set the color hold.

as sparky mentioned, I'd suggest vinegar and let us know if that helped.