As I often translate chemical texts from English into Spanish, I would like to add some interesting glossaries.
A glosary with many chemical products in English. The entries include formula, IUPAC name, synonyms, characteristics, etc. Very useful when you are looking for the right translation into Spanish.
A dictionary of laboratory terms (English-Spanish). Includes common acronyms. You must change the last letter of the link (dictp) in order to look for another initial, e.g. dicta, dictb, dictc, etc.
Superfund´s Bilingual Dictionary. EPA related terms.