Can you earn too much of a salary and be disqualified from getting Canadian/Albertan student loans?

I'm reading through how Alberta and Canada student loans work and I can't for the life of me find if there is a cut off of how much you can earn per year, and if you're cut off from being eligible for student loans.

I've had people at work comment "I can't get student loans because I earn too much", but I can't find any information about there being a cut off for earnings. I know there is one for grants, but does this limit exist for government loans?