In many instances, manufacturers want to add the actual list of ingredients but because the list provided by American Association of Plant Food Control Officials (AAPFCO) is stringent and restricts the labeling section, many ingredients are hidden from buyers. Because of this buyers are unaware of the beneficial ingredients present in the product. Manufacturers cannot even label the products' ingredients as "other ingredients"; otherwise the product will be yanked from the shop and the manufacturer will be fined. To make it worse each state has different label laws which the manufacturer has to follow.
Here's another problem, many companies do constant research to improve their products and when they produce such products they can't even label them "new and improved" because that would include submitting new labels with reports to 50 state regulators for every product every year, which is a very expensive procedure.
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http://www.rosebudmag...are-not-telling-truth