system
Given the following post, respond as if you're commenting on Reddit:
human
Why are some common lab-grade reagents used in food production, such as NaCl, labeled as "lab use only" and "not for consumption"?

I have a 12 gallon HDPE chemical container with a NaCl MSDS attached to it. I want to use for storage of food grade liquids, but the container says the NaCl is for lab use only and not for consumption. By all accounts, my other containers should not be used for storage as they once held acids of various types. If cleaned and sanitized using food-safe chemicals, why should I not use these NaCl containers?
gpt
Chemicals intended for human consumption need to be handled in more stringent environments than research chemicals.  For research chemicals, nobody freaks out if the reactor you used to crystallize sodium chloride was used to crystallize sodium cyanide the week before.  But they would if people were going to consume that salt.  If a chemical is meant to be eaten, it must also go through additional testing to ensure that it's not contaminated with specific toxic substances.  There are no regulations about what research chemicals can be contaminated with.  Researchers do typically demand that their chemicals be analyzed so they know what they're using, though.

Containers are the same.  Plastics can be contaminated with all sorts of plasticizers and catalysts that you don't want to eat.  Food grade plastics have minimized those impurities.  Chemical storage plastics are chosen for their durability, not their lack of toxicity.

I don't see any reason to risk it.  Buy food safe containers.