SPADA Book - April 11, 2017

DRAFT ENVIRONMENTAL ORGANISMS PANEL, VERSION 5

Environmental  Factors For Validating Biological Threat Agent Detection Assays 1 2 [Adapted from the Environmental Factors Panel approved by SPADA on June 10, 2010.]  3 4 The Environmental Factors Studies supplement the biological threat agent near‐neighbor exclusivity  5 testing panel.   There are three parts to Environmental Factors studies:  part 1 ‐  environmental matrix  6 samples;  part 2 ‐ the environmental organisms study; and part 3 ‐ the potential interferants applicable  7 to Department of Defense applications. 1 12 13 Method developers shall obtain environmental matrix samples that are representative and consistent  14 with the collection method that is anticipated to ultimately be used in the field.  This includes  15 considerations that may be encountered when the collection system  is deployed operationally such as  16 collection medium, duration of collection, diversity of geographical areas that will be sampled,  17 climatic/environmental conditions that may be encountered and seasonal changes in the regions of  18 deployment.   19 20  Justifications for the selected conditions that were used to generate the environmental matrix and  21 limitations of the validation based on those criteria must be documented.  22 23  Method developers shall test the environmental matrix samples for interference using  samples  24 inoculated with a target biological threat agent sufficient to achieve 95% probability of detection.  25 26  Cross‐reactivity testing will include sufficient samples and replicates to ensure each environmental  27 condition is adequately represented .   32 To evaluate robustness to soil interferents, samples of each regional soil types* should be spiked at 2x,  33 5x and 10x AMDL with the archetype organism (usually specified in the SMPR for AMDL testing, such as  34 strain CO92 for Yersinia pestis  in SMPR 2016.008) and then the samples evaluated for inhibition.   35 Inhibition testing should be done using intact target organisms so that potential interference can be  36 determined.    8 9 Part 1:  10 11 Environmental Matrix Samples ‐ Aerosol Environmental Matrices   28 29 30 31 Interference from Soil 

37 38 39 40 41 42

* Arizona Test Dust is available as a baseline starting point. 

1 Added in June 2015 for the Department of Defense project.