"When in doubt,
throw it out."
If I get a bleeder - which I want to know about before I start cutting -
1) I will try to return it if I still have the sales slip - sometimes my fabric sets for years before I get around to doing anything with it -
2) if no sales slip (dated fairly recently!) , I discard it - much as it causes me pain to do so. But it would cause more pain to me if I used it.
I had some black cotton fabric disintegrate in the washer, too. I had bought two bolts of different shades of navy blue and one bolt of black - same manufacturer - at the same time. I just washed some more of the blue last fall - it's fine.
I also had black dust "everywhere" from it. It made quite a mess in the washer, too.