Here is a good source of info: http://yarchive.net/chem/chemical_grades.html
I frequently use reagent grade chemicals internally. If you go to the FDA definition of allowable pharmaceutical grade impurities you will see almost no difference between reagent and pharmaceutical grade chemicals. Actually pharmaceutical grade is often less stringent than reagent grade. That is because reagent grade chemicals are often used in making pharmaceuticals. A main issue is the amount of heavy metals in the chemical. Usually you can request a copy of an assay of the reagent or technical grade chemical and see what if any heavy metals are present. If you use chelators regularly (bentonite, ALA, chlorella, etc) you may not be as concerned about heavy metals. Reagent grade is a higher purity than technical grade. From thr Sci-Tech Encyclopedia: "Commercial chemicals are available at several levels of purity. Chemicals labeled "technical" or "commercial" are usually quite impure. The grade "USP" indicates only that the chemical meets the requirements of the United States Pharmacopeia. The term "CP" means only that the chemical is purer than "technical." Chemicals designated "reagent grade" or "analyzed reagent" are specially purified materials which usually have been analyzed to establish the levels of impurities. The American Chemical Society has established specifications and tests for purity for some chemicals. Materials which meet these specifications are labeled "Meets ACS Specifications." I do use some technical grade chemicals where it is not possible or it is difficult to get reagent grade. And I do use chelators. When deciding to use a technical grade I try to get a copy of an assay. If no assay is available and the amount used is low and the purity is reasonably high I might still use it. There is no absolute answer to your question. - Steve N -----Original Message----- From: Annie B Smythe [mailto:anniebsmy...@gmail.com] Sent: Tuesday, January 12, 2010 5:08 AM To: CS List Subject: CS>Chemistry question ? Question for chemistry knowing folks. What's the difference between technical grade and food grade? Is technical grade the same as lab grade? And would technical grade magnesium chloride powder to be unsafe to make a solution from for a person to drink as magnesium supplementation? Any impurities or anything? Annie -- If we could sell our experiences for what they cost us, we'd all be millionaires. Abigail Van Buren -- The Silver List is a moderated forum for discussing Colloidal Silver. Instructions for unsubscribing are posted at: http://silverlist.org To post, address your message to: silver-list@eskimo.com Address Off-Topic messages to: silver-off-topic-l...@eskimo.com The Silver List and Off Topic List archives are currently down... List maintainer: Mike Devour <mdev...@eskimo.com>