The revised monograph will be the new standard for glycerin in the US and must be used by both manufacturers using glycerin and the original producer to test that diethylene glycol is not present, following recommendations from the FDA in May 2007.
The revised monograph becomes official 15 May 2008 and differs from its predecessor in two ways.
Firstly, in the Identification B procedure of the monograph, a gas-liquid chromatographic with flame ionization detection (GC/FID) test will be employed to detect if glycerin, diethylene glycol and ethylene glycol are present by a peak at their respective relative retention times.
If a peak is detected for either of the impurities in this procedure the monograph will direct the user to quantify the impurities.
The second revision to the monograph involves the replacement of the test "Limit of diethylene glycol and related compounds" with a new procedure.
This new diethylene glycol and ethylene glycol impurities test is capable of quantifying the impurities when found at or above the limit of quantitation (0.025 per cent).
The danger posed by these impurities was brought into sharp focus by the case in Panama in 2006 where diethylene glycol was falsely labelled as the more expensive glycerol, resulting in some one hundred fatal poisonings.
By ensuring that glycerin is tested by those who buy it, as well as those who make it, the FDA is trying to prevent an event similar to the one in Panama occurring in the US.
The new monograph should reduce the likelihood of further contaminations but Roger L. Williams, MD, USP's executive vice president and chief executive officer, says the organization isn't resting on its laurels and is working to strengthen the safety nets in other areas.
He said: " Other useful ingredients similar to glycerin may be susceptible to diethylene glycol contamination .
" USP is working now to adjust monographs for these ingredients, just as it has the USP Glycerin monograph ."
Diethylene glycol has also been recently found in counterfeit toothpaste in Panama, Costa Rica, Spain, the UK and the US.
There were no recorded fatalities from these toothpastes but diethylene glycol is associated with renal failure even in small quantities.