In the course of a recent data validation project for an oil and gas production client, Environmental Standards’ quality assurance chemists discovered, yet again, why data validation is so important in generating accurate and defensible data. Our chemists identified an issue during post-digestion spikes (PDS) for metals analysis. The client’s Quality Assurance Project Plan (QAPP) indicated that a PDS should be analyzed for only those compounds that fail in the pre-digestion MS/MSD.
During validation, we saw that in the MS/MSD analyses, two metals failed acceptance limits; accordingly, the analytical laboratory ran a PDS. However, due to software limitations, the laboratory reported the full metals list in the PDS instead of just the two metals. Because Environmental Standards’ quality assurance chemists saw the full metals list, they could see that all metals failed quality control requirements in the PDS with very high recoveries.
Because these results were so “weird,” the laboratory – at the request of our quality assurance chemists – looked into the results again and found a process error that resulted in the PDS being double-spiked. The lesson-learned is that data validation and environmental chemistry quality assurance of your analytical laboratory is absolutely necessary – even if the laboratory is accredited.
For more information about Environmental Standards’ chemistry quality assurance services and experience, contact David R. Blye, CEAC at 610.935.5577.