Demystifying Isotope Dilution for Mass Spectroscopy

Data Quality, Management and Review
Oral Presentation

Prepared by C. Appleby1, S. Myer2
1 - U.S. EPA OLEM/OSRTI/ASB, 980 College Station Rd, F104-2, Athens, GA, 30605, United States
2 - U.S. EPA OLEM/OSRTI/ASB, 1200 Pennsylvania Ave., NW, MC5203P, Washington, DC, 20460, United States

Contact Information:; 703-405-0057


The concept of isotope dilution used in mass spectrometric methods still mystifies many who are thoroughly familiar with external or internal standard calibration procedures. The technique is used in high-resolution Dioxin and PCB congener methods (EPA methods 23, 1613, 1668, and 8290), EPA Methods 1624 and 1625 for volatile and semivolatile priority pollutants, and PFAS method SW-846-8328, now in development.

This presentation will present the basic approach and typical calculations involved in isotope dilution calibration, using examples from current applications. There will be time for discussion and questions.