Water-wise (or not) drip system

So, I got the bright idea from somewhere, can't remember where now, to recycle my plastic mineral water bottles into drip systems for my potted plants. I punched 2-3 holes in the top of the lid with a push pin, filled them with water and then turned them upside down and put them in my big pots of cucumber, zucchini and tomato.  Worked well for the most part, but in some cases I needed to add more holes or re-punch the holes to widen them if they got clogged with the potting soil.  This produced a slow drip system for each pot that would water over 1-2 days. Genius! You can see something similar at yougrowgirl.com. Then when I showed my oldest daughter my new contraptions, she asked the question that had been nagging at the back of my brain, "What about BPA?" BPA is a substance in most plastic used for food and beverages and is considered safe in small doses per the FDA, but why take chances. Theoretically BPA could be released from the plastic by the sun's heat and then absorbed by the plants into the fruit we eat, which sounds pretty nasty. I'll switch to glass wine bottles with the screw caps and see if that works.