Photo courtesy of ajr595 at Flickr.com.
Greenhouse Polycarbonate should never be cleaned with bleach. Because of its light weight, strength, flexibility, and translucency, polycarbonate plastic is often used in greenhouses and other gardening structures — but this can be a disadvantage when it’s time to clean and disinfect at the end of the growing season.
The organic gardener is limited to only a few effective disinfectants (see the Organic Material Review Institutes website for more information), and bleach is not one of them. In any case, you can’t ever use bleach on polycarbonate objects; it not only damages the plastic, it also reacts chemically with it to release a nasty long-term poison called Bisphenol-A. Also known as BPA, this chemical can cause hormonal changes in both humans and animals.
There are a few cleaners that you can safely use on polycarbonate, but they require more elbow grease than most commercial preparations. Soap and water works; so do 95-100% ethyl or isopropyl solutions, as well as weak vinegar (acetic acid) solutions. All these are allowed under most organic standards. If you want to avoid the situation altogether, use glass in your greenhouse rather than polycarbonate. It shatters more easily and is usually more expensive, but it’s completely non-reactive to almost everything.
Photo courtesy of Rusty_Shackelford at Flickr.com.