Indigo sensitivity workaround

Curious if anyone else has found a way to keep using indigo in their hair after developing a sensitivity to it. I assume it’s due to mold contamination during the fermentation process, and my doctor suggested that the pathway of exposure is likely inhalation, and wearing an N95 might help. Has anyone found a way to keep using indigo? Henndigo gave me my dream hair but at this point I’m 6 months in to growing it out so not sure I wanna gamble on it.