Google search the POP analysis. There is a US based company which does something similar to what you do. Probably, you may be able to get them hold

You probably can identify congeners just based on MS or MS/MS data, using your native standards. However, for quantification it is a common norm to use internal standards for POPs analysis. Most will use 13C labelled internal standards, but you can also use something else. For example, some PCB congeners do not occur in environmental samples and you can use those as your internal standards. Without internal standards, I am afraid it would be very difficult to obtain high-quality data.

Dear Mohommad,

Actually, You can’t get idea about concentrations and amount of POPs without injecting internal standards to the GC-MS but you can identify the compounds through the GC-MS library. Better to get clear idea about retention time, major mass fragments and peak area for all detectable peaks and names of the compounds which are available in the updated library. Further, you have to consider the match score (high score shows more similarly) of the given name and the identified compounds. So, this may help you to consider the possibility of a particular compound being present or not in your sample. Important when you selecting peaks for their match with the library, you would certainly miss out compounds not listed in the library.

Thank you very much for your clarification

I will try to use the identifier comounds available in our to judge on my readings and make some generalization to the obtained results

Dear Mohammed O.A. Mohammed,

It is not possible to quantify without calibration stranded. but internal standard is not compulsory if you have individual standard compound. sometime library machine is not useful. So that you have to find standards compound