Elimination: solvent elimination
Elimination is the pinnacle of the hierarchy of controls
because it completely removes the hazard from the work
environment. The pharmaceutical industry has been
employing sustainability principles, thereby improving
productivity for several decades. The synthesis of
Pregabalin, a pharmaceutical treatment for the nervous
disorders such as epilepsy and social phobia, provides
insight into how the elimination step of the hierarchy of
controls and green chemistry suite work hand in hand.
Originally, the Pregabalin synthesis process included the
disposal of half the synthetic materials used to create the
compound [31]. After pharmaceutical manufacturer
Pfizer completed an enzymatic screen, the company
identified two new enzymes which eliminated several
chemical conversion steps, increased production speed,
and reduced waste [31]. These improvements were
based upon the E-factors of the compounds but had the
added benefit of the removal of various solvents during
the synthesis process. Not only did this improve efficiency,
but it also reduced worker exposures during the
disposal process.