19th Needle/Leaf Interlaboratory Comparison Test 2016/2017

Wien

2017

37S. + Annex-Results

Monographie

978-3-902762-72-6

202286

INTRODUCTION; TASK, MATERIAL, PARTICIPANTS, EVALUATION ; Task ; Material ; Participants ; Data Evaluation; RESULTS ; Main results of the questionnaire ; Results of the 19th Interlaboratory Comparison Test ; Comparison between the 19th Interlaboratory Test and former tests ; Evaluation by element ; Nitrogen ; Sulphur ; Phosphorus ; Calcium ; Magnesium ; Potassium ; Carbon ; Zinc ; Manganese ; Iron ; Copper ; Lead ; Cadmium ; Boron ; CONCLUSIONS; OUTLOOK; LITERATURE; List of laboratories and responsible persons ; Method Code ‐ Pretreatment ; Method Code ‐ Determination ; List of abbreviations ; ANNEX ‐ Results
45 laboratories in 22 countries participated in the 19th Needle/Leaf Interlaboratory Test, but only 44 laboratories submitted their results in time. A new system for qualification and re‐qualification started with the 11th test in 2009. This system was enlarged after the manual update in 2010 to all ICP‐Forests partners (see König et al. 2010 and 2013, Rautio et al. 2010 and 2013 Pitman et al. 2010). With the ring test report, each participant receives a qualification report which can be download from the webpage (https://bfw.ac.at/ws/ring_nadel.login). It has been decided to qualify the results of each parameter separately. A laboratory is qualified when 50% or more (generally two, three or all four samples) of the results for this parameter for all the samples of the ring test are within the tolerable limits. Re‐qualification is mandatory for all ICP‐Forests laboratories if monitoring results (foliage, litterfall, ground vegetation) from the vegetation period 2016 will be submitted to PCC in autumn 2017. The usage of maximum acceptable limits of quantification (LOQ) has been included since the 14th Interlaboratory Test. These limits are needed, because many laboratories are using multi element methods (mostly ICP‐AES) with higher LOQs for some elements. But for evaluation and classification of the monitoring samples real measured results and lower LOQ are needed. The Working Group QA/QC in Laboratories received a task to fix this problem from the Expert Panel Foliage and Litterfall (12th Meeting ‐ Tallinn 2011). Maximum acceptable LOQs for mandatory and optional parameters for foliage, litterfall and ground vegetation were discussed and accepted in the 3rd Meeting of the Heads of the Laboratories (Arcachon 2011). This problem is more or less fixed now – only two laboratories submit
LOQs higher than the maximum acceptable LOQs (A49 for Pb and F18 for B).