Factors concerning the Difference in Results among Three Determination Methods for Geosmin in Environmental Water

Geosmin concentrations of Lake Shinji were compared with three measurement methods that were defined in the clean water test method. Because geosmin was mainly contained in algal cells, the concentration measured by solid-phase extraction - gas chromatograph mass spectrometry (SP-GC/MS), which carried out filtration, was extremely low. When comparing the measured concentrations of purge trap-gas chromatograph mass spectrometry (PT-GC/MS) and the head space - gas chromatograph mass spectrometry (HS-GC/MS), the value of the latter was higher. The reason was thought to be that the former is heated to 40 degrees C, but the latter is heated at a high temperature of 80 degrees C, and thus the algal cells are more degraded; therefore geosmin, which was present in the body, was eluted. Like this, it became clear that the concentration of geosmin differs depending on the measurement method.