13 Analysing samples from the bay

• Click on the ‘Sampling’ tab within the software, and choose one of the sampling sites that you selected in your sampling plan to analyse using GC–MS.
• Move to the ‘Analysis’ tab and run the GC–MS spectrum of your first sample. The retention time of each peak is provided in the table in the software, together with the peak areas. You should use a second table to make a note of these data in your notebook. To run replicate analyses, press ‘Clear’ then ‘Run’. You should take the mean of the peak areas for the different peaks identified.
• Use the data that you derived from the standard and the pesticide library to identify any pesticides present and record your findings in your table. (You may view the mass spectrum of each pesticide by clicking on the number above each peak to confirm this, should you wish to.)
• Repeat this process for the other samples sites that you selected.