Hello Libby,

ESdat will only sum the compounds that are reported.  This means that if only some of the compounds are reported the "Combined Compound" will only be a sum of those present.  If none are present you wont get a "Combined Compound"

If some are missing and if you select to include result comments in the Chemistry Output Table a comment to this effect will be flagged for the result.

If different labs are producing different compounds (eg total xylenes from one lab, and seperate o, m, p xylene results from another) that need to be summed, you will need to cover both in the summation.  However, if you include both and the lab reports both then you need to be aware that this may have the effect of double counting.

Alex.

Hello Libby,

If your combined compound is not appearing you will need to check the following:

• Are the compounds that get added together to produce the combined compound appearing in outputs?
  
  
• Have you checked that the compounds that get added together are named as you expect and consistent with the used by ESdat such as in the output table?
  
  
• Do you have any unit conversion issues?
  
  
• Do you see any results in the Chemistry_Results data table with a Method Name of "ESdat Combined"?
  
  
• the Combined Compound could be getting reported elsewhere in the output table, depending on your grouping options 

Alex.