I also have hair loss, and my brother and father do not.
I never thought about mercury fillings being the cause, and don't remember now the correlation of Dentist to hair loss, but I do know I starting catching colds after a dentist visit in my twenty's.
And also two times I used Head and Shoulders, just tones of hair came out afterwards...
The Industrial De-greasers might not help as well in the hair care products. Course I also started to smoke around that time to, not my scalp but cigarettes.
Not sure your ages but I just turned fourtyfive, I've seen a few older brothers with hair loss, where there younger brothers are not effected, wonder if we or I got something different in an inoculation back then.

Also Canola and Soy are being pointed out for blocking the capileraries in the eyes, so might also block the supply to the hair follicles to.

But Mercury is an Idea I will have to look further into...