- EQAS  samples for Non-Threshold Substances   For Non-Threshold Substances , the concentration in the EQAS  sample will be guided by, but not limited to, one of the following criteria:  o Concentrations  of the Prohibited Substance and/or its Metabolite (s) or Marker (s) equal to or greater than (≥) the applicabl e MRPL  (refer to TD MRPL);  o Concentrations  of the Prohibited Substance  and/or its Metabolite (s) or Marker (s) between 50% of the MPRL  and the MRPL  (applicable only to Non-Threshold Substances  prohibited at all times and with no Minimum Reporting Levels , as per TD MRPL);  o Non-Threshold Substances  with Minimum Reporting Levels  as stated in the TD MRPL ( e.g.