Using EPA method 1631, we’re analyzing aqueous samples for TOTAL inorganic mercury down to 0.5 part per trillion levels by oxidation, purge & trap, and Cold Vapor Atomic Fluorescence Spectrometry. In order to speciate and look for ORGANIC or methyl mercury down to 0.05 par per trillion levels, we have installed a new technology Tekran distillation and instrument unit calibrated to analyze aqueous samples by method EPA 1630 using a distillation, ethylating, purge & trap, gas chromatography and cold vapor atomic fluorescence spectrometry.
Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide), which is the source of the red pigment vermilion, and is mostly obtained by reduction from cinnabar. Cinnabar is highly toxic by ingestion or inhalation of the dust. Mercury poisoning can also result from exposure to water soluble forms of mercury (such as mercuric chloride or methyl mercury), inhalation of mercury vapor, or eating seafood contaminated with mercury.
The United States Clean Air Act, passed in 1990, put mercury on the list of toxic pollutants that need to be controlled to the greatest possible extent. Thus, industries that released high concentrations of mercury into the environment agreed to install maximum achievable control technologies (MACT). In March 2005, an EPA rule added power plants to the list of sources that should be controlled and a national cap and trade rule was issued.
The California State Water Quality Control Board who regulates industries and NPDES permits throughout the state require continuous monitoring of mercury levels. The EPA 1631 method has the lowest reporting limits technologically offered to monitor these operations.