FIRST-SOLUTION

Is a chemical precursor used in the manufacture of drugs that are in control. In general precursor used legally / officially in industrial processes and most traded in international trade.
These chemicals are not in the special supervision, but the export and import and supply of precursors to individuals and companies whose use is not for use in industry is an indication that there is a possibility of these activities is illegal activities.

The term precursor is used for materials that do not need the drugs, but used in a variety of ways to process or make narcotics or psychotropic drugs.

Depending on their chemical properties, chemical precursors can be joined with other substances to be drugs (or in the form of an intermediary), or can work as a substance acid (in the drug salt formation).

UN Convention in 1988 has included 22 kinds of precursors to the list of international supervision, but do not use the term precursors, but called it "The material is often used for the manufacture of illegal narcotics or psychotropic " Though technically not true, but it has become customary to refer all such substances with a precursor.