Ammonia Methods and the Silly EPA

Methods of analysis for ammonia in soil and water extracts rely, for the most part, on reactions that date bak two centuries. Not that it is bad 'cause if something works it works, but you'd think that in this day of technology it would be allowed by our government to at least take advantage of some new things. Not that we don't take advantage of the instruments that are available since 1830, but we seem stuck to the technology that was established in the Nixon administration. Hello EPA , there is more than one way to skin a cat.

The method most used by environmental labs for the determination of ammonia is EPA method 350.1 based on the Berthelot reaction. In this method, ammonia is converted to chloramine that reacts with phenol under basic conditions to create an intensely blue indophenol dye that's color is directly proportional to the ammonia concentration. The reagents are added together using a segmented flow analyzer (SFA), and mor recently Flow Injection Analyzers (FIA).

Nowadays we have a new analyzer on the scene that is being marketed as a Discrete Analyzer. Where the silliness begins is in the way and order reagents are added because our EPA insists that these Discrete Analyzers duplicate the action of the flow analyzers. The problem is that discrete analyzers are not flow analyzers. The best way to bring about the berthelot reaction is not neccessarily equally and independent of the type of analyzer.