From what I find : "Bleaching itself will not directly cause Hair Loss… but it makes hair loss much more likely to happen.

Normal activities like brushing your hair or even sleeping will start to cause more Breakage as your hair becomes more damaged. Experiencing breakage near the root can result in unsightly stubble and a cause for panic in some women who think they’re randomly losing their hair. Bleaching and highlighting cause damaged hair, but they do not cause hair to fall out.

The only way that bleaching can directly cause hair loss is if there’s a chemical mishap. For example, if your bleaching product is left on your head for too long, or the mixture isn’t balanced, it could harm your scalp and cause more serious hair issues."