For Non-Threshold Substances  with Minimum Reporting Level s as specified in the TD MRPL, Adverse Analytical F inding  decisions for the “A” Sample  should be based on the identification of the Non-Threshold Substance  or its characteristic Metabolite (s) or Marker (s), in compliance with the TD IDCR, at an estimated concentration greater than the Minimum Reporting Level , unless there is    ISL – January 2021 Page 92 of 160 justification  for reporting the finding at levels below the Minimum Reporting Level  (e.g.