A fifth digit "may be adopted for use on non-conventionally grown product", such as organic (prefixed by a '9') or genetically modified (prefixed by an '8').[2] The idea that such prefixes can be reliably used by consumers to tell whether a product is genetically modified or not has been called an urban legend by Jeffrey M. Smith writing on The Huffington Post.[3] However, the July 2012 Produce PLU Codes User's Guide prepared by the International Federation for Produce Standards specifies that three categories have been established for the fifth (leading) digit qualifier. A '9' identifies organic produce, an '8' indicates genetically modified produce, and a '0' or no fifth digit indicates non-qualified produce.[4] Thus, (if "no fifth digit" indicates "non-qualified produce"), all common produce, for example the Pink Lady apples in the illustration, are "non-qualified."