I studied industrial chemistry at the bachelor's level and graduated with a third class. So now I am looking for a school offering postgraduate studies in environmental chemistry and toxicology or environmental health before applying for a master's program with a good grade. Please, I am open to directions, thanks.

I need to find two referees for my application I lost my course adviser some years back and, my project supervisor is not helping out and, the other lecturers I contacted said they can't help either.
I have those I could use as professional referees, but they requested academic referees alone, please what should I do?
If I could get one academic referee, can I use one professional referee to replace the academic referees?