Health

Adulteration is deliberate, usually in an attempt to charge full value for a cheaper "substitute". Contamination may be accidental, even unavoidable, and not always particularly harmful, depending on the contaminant and the way the product is used.

The infamous case of infant formula poisonings in China several years ago was a case of adulteration -- sellers were paid for nitrogen content based on the simple-minded standard that more nitrogen content meant more protein, when really it could be almost any kind of nitrogen. Toxic, nitrogen-rich industrial waste was cheaper than protein but brought the same profits while deceiving parents who unwittingly poisoned their children.

There seems to be a certain class of fraudsters who have realized that it's easier to get away with adulterating products served to children.