[limchinchuan]

Dear Forum,
I am a microbiologist in a medical devices company, our sterilization process are using Ethylene Oxide. Hence we need to perform performing Ethylene Oxide residual test using Gas Chromatography.

In the validation on the test method, we had determine the Quantitation Limit and Detection Limit for the GC.

In the reporting of the result, i am requested to only report those data above Quantitation Limit.

Should all the data below Quantitation Limit but above Detection Limit ignored?

What is the rationale behind this?

Thanks.

[marquis]

It varies from company to company.  Often, below the detection limit will be reported as "none detected" or nd, and below the quantitation limit will be reported as "less than (quantitation limit)". 

When the test moves to production or QA/QC, the most common result is "less than (quantitation limit)".

Most US companies have moved away from EtO sterilization.  Often, they no longer include the gas permeable membrane in their IV sets.  Is this a special application or new use of Eto?

Thanks for the info.

[limchinchuan]

This is not new use of the ETO. WE had been using ETO sterilization for sometime.

Just wondering on the reporting limit should set at Quantitation Limit or Detection Limit.

As detection limit mean the lowest level of detector distinguish noise from signal. While quatitation limit is the lowest level of compound can be reliably quantified.

If we report Quatitation Limit, the value we obtained in between QL and DL are ignored, those value are still representing some compound which is not accurately quantified.

This is against  the practice of reporting "worst case scenario". 

Any comment are welcome for this discussion. Thanks

[zoork34]

If your test reveals an EO concentration that is detectable, but below the quantitation limit, maybe it should be reported as a "trace" amount since you cant quantify it?  Just a suggestion.