Total Impurities Calculation

[jayroseville58]

On Calculation of Total Impurities, Should I include the values generated below LOQ? Thanks.

[HPLCaddict]

Values below LOQ are by definition "nq", i.e. not quantifiable. There are no values below LOQ!!

[Kreall]

Every impurity method should have DL limit incorporated. DL= Disregard limit, limit below which you reject any peaks you have (for many cases the limit is 0,05% of active substance). Ideally LOQ should be equal to or less than the DL. (2.2.46. Chromatographic separation techniques, Ph. Eur.)