For the Canadian schools, generally what matters most is having a PI that wants you in their group. It is extremely common in Canada for students to meet with PI's/talk to them on the phone before even applying. I would suggest contacting potential advisors and telling them about your research experience and interests. If they are keen to have you join their group, the particulars about your GPA aren't as big a concern. Although, I should note that it can sometimes be harder for international students, especially at U of T, and the groups that focus on asymmetric catalysis and green chemistry are some of the most competitive to get into.
Of course the process is different for American schools. Maybe ask a faculty member that you know from undergrad if they think you should explain the lower semester.