i don't think so , cuz lye is the stuff that "sometimes" is used to unblock the pipes, as it dissolves/thins  fat,but im not sure about keeping it there for long periods of time,why not use glass? a pickle jar will do just fine plus normally comes with a lid ,so you can close it a shake the mix

about solvent in not sure if it damages the pvc , but it definitely damages the water environment as it other solvents aswell .you can check it online , just Google-it  

hope it helps