this lady warned me not to eat ANY vegetable that had been grown with river water. She apparently had seen a report on CNN that warned Americans to stop eating vegetables grown with river water anywhere in the US, didn't matter what river it was? What's that about?I consider water quality to be a dark art best left to the scientists, but many companies are out there trying to make one source of water look dangerous so you will buy their source of water.* This unethical conduct in the name of business profits bothers me.
Bottom Line: Credence goods (you have to believe they are good/bad for you) are especially vulnerable to manipulation. Water is one of them and there are many con artists willing to take advantage of you.
* I drink tap water in most places but not in developing countries. Most river water has traveled through someone's toilet (e.g., San Diego's water has been through 12 municipal water systems), but that water is treated to be potable.