Analytische Qualitätssicherung Baden-Württemberg

Transcription

1 Analytische Qualitätssicherung Baen-Württemberg Proficiency Test 1/13 TW S1 sweeteners an benzotriazoles in rinking water acesulfam, cyclamate, saccharin, sucralose, 1H-benzotriazole, 4-methyl-1H-benzotriazole, 5-methylbenzotriazole, sum of methyl-1h-benzotriazoles provie by AQS Baen-Württemberg at Institute for Sanitary Engineering, Water Quality an Soli Waste Management, University of Stuttgart Bantäle 2, Stuttgart-Büsnau, Germany an IWW Water Center Moritzstr. 26, Mülheim an er Ruhr, Germany on behalf of Lanesanstalt für Umwelt, Messungen un Naturschutz Baen-Württemberg Stuttgart, in July 2013

2 Responsibilities: Scientific irector AQS: Dr.-Ing. Dipl.-Chem. Michael Koch PT manager: Dr.-Ing. Frank Baumeister AQS Baen-Württemberg at Institute of Sanitary Engineering, Water Quality an Soli Waste Management at University of Stuttgart Bantäle Stuttgart-Büsnau Germany Tel.: +49 (0)711 / Fax: +49 (0)711 / info@aqsbw.e

3 PT 1/13 TW S1 LIST OF CONTENTS GENERAL... 1 PT DESIGN... 1 SAMPLE PREPARATION... 1 SAMPLE DISTRIBUTION... 1 ANALYTICAL METHODS... 2 SUBMISSION OF RESULTS... 2 EVALUATION PROCEDURE... 2 ASSESSMENT... 3 EVALUATION... 3 EXPLANATION OF APPENDIX A... 4 EXPLANATION OF APPENDIX B... 5 EXPLANATION OF APPENDIX C... 5 MEASUREMENT UNCERTAINTY... 6 TRACEABLE REFERENCE VALUES... 7 INTERNET... 8 Appenix A ACESULFAM... A-1 CYCLAMAT... A-7 SACCHARIN... A-13 SUCRALOSE... A- 1H-BENZOTRIAZOL... A- 4-METHYL-1H-BENZOTRIAZOLE... A-33 5-METHYL-1H-BENZOTRIAZOLE... A-37 SUM OF BENZOTRIAZOLES... A-43 Appenix B Appenix C ACESULFAM... C-1 CYCLAMAT... C-10 SACCHARIN... C- SUCRALOSE... C-28 1H-BENZOTRIAZOEL... C-37 4-METHYL-1H-BENZOTRIAZOLE... C-46 5-METHYL-1H-BENZOTRIAZOLE... C-55 SUM OF BENZOTRIAZOLES... C-64

4 PT 1/13 TW S1 page 1 General This PT was provie by AQS Baen-Württemberg in cooperation with IWW Water Center in Mülheim an er Ruhr an with the network NORMAN (Network of reference laboratories for monitoring of emerging environmental pollutants). In this roun acesulfam, cyclamate, saccharin, sucralose, 1-H-benzotriazole, 4-methyl-1Hbenzotriazole, 5-methyl-1H-benzotriazole an the sum of the methyl-1hbenzotriazoles were to be etermine. The PT was supporte by Lanesanstalt für Umwelt, Messungen un Naturschutz in Baen-Württemberg. The PT was execute an evaluate accoring to the requirements of DIN A45 an ISO/TS PT esign Each participant receive the following samples: 3 samples for the etermination of acesulfam, cyclamate, saccharin, sucralose, 1H-benzotriazole, 4-methyl-1H-benzotriazole, 5-methyl-1Hbenzotriazole in 1000-ml-groun bottles. The samples were preserve by aing 40 mg/l soium azie. The samples also containe acetonitrile as solubility promoter. 3 ifferent concentration levels/batches were prouce. All participants receive the same samples. Sample preparation The samples for the etermination of the sweeteners an benzotriazoles were base on a real groun water matrix from the northern part of the region Ruhr in North Rhine-Westphalia. The groun water was use without treatment for the sample preparation. The groun water was spike with stock solutions an the concentrations covere rinking an groun water relevant ranges. Sample istribution The samples were ispatche on 29 th January 2013 by express service.

5 PT 1/13 TW S1 page 2 Analytical methos The participants were free to choose a suitable metho, but following limits of quantification were require: parameter acesulfam cyclamate saccharin sucralose 1H-benzotriazole 4-methyl-1H-benzotriazole 5-methyl-1H-benzotriazole limit of quantification 0,05 µg/l* 0,05 µg/l* 0,05 µg/l* 0,1 µg/l 0,05 µg/l 0,05 µg/l 0,05 µg/l *concentration referre to the aci an not to the salt of the respective substance The samples ha to be analyse in uplicate over the complete metho (sample preparation an measurement). The participants were aske to report the result as average value in µg/l. The concentration for the parameters acesulfam, cyclamate an saccharin referre to the aci form of the sweeteners an not on the respective salt. The samples containe 4-methyl-1H-benzotriazole an 5-methyl-1H-benzotriazole. In the case that both substances were quantifie separately, the single values ha to be reporte as well as the sum of both substances. Otherwise the sum of both substances ha to be reporte. The participants were aske to report the results with three significant igits. Submission of results The ealine for the submission of results was on 28 th February Evaluation proceure The statistical evaluation was execute accoring to DIN A45 an ISO TS Interlaboratory comparisons for proficiency testing of analytical chemistry laboratories. From the participants results a relative stanar eviation was calculate for each concentration level an parameter using the Q-metho. The reference values (see chapter Traceable reference values ) were use as assigne values x a. The stanar eviation resulting from the Q-metho was use as σ ). σ ) was limite as follows: lower limit: 5% upper limit: % A z-score was calculate for each measurement result erive from the assigne value x a an the stanar eviation for proficiency assessment σ ) : result z score = σˆ x a The z-score was moifie to a z U -score with a correction factor for proficiency assessment (as escribe in the stanars mentione above). The tolerance limit was efine as Iz U I=2,0.

6 PT 1/13 TW S1 page 3 Assessment There was no overall assessment of the proficiency test roun, but the single parameters were assesse. A parameter was assesse as successful, if more than half of the values were correctly etermine (2 out of 3 values are within the tolerance limits). Evaluation Number of participants: 36 1 laboratory i not report any result. Number of reporte values: 591 Number of accepte values: 511 (86,46 %) In the following figure the successful an not successful laboratories for each parameter are illustrate.

7 PT 1/13 TW S1 page 4 Explanation of Appenix A Appenix A contains for each parameter - parameter tables - a figure of participants means versus the spike amounts for the etermination of the recovery rate - a figure of the relative stanar eviations versus the concentrations - a figure of the tolerance limits in the PT versus the concentrations - the frequency of application of analytical methos - the metho specific evaluation - a comparison of mean an reference values for each concentration level - a comparison of the relative stanar eviations of the ifferent methos - the statistical characteristics of the metho specific evaluation - a tabular comparison of the means with the reference values an their uncertainties Parameter tables In these tables the following values for each concentration level are liste: assigne value expane uncertainty of the assigne value in %, calculate accoring to ISO 128 using the formula rel. stanar eviation U = 2 1. number of values stanar eviation, calculate using robust statistical metho stanar eviation for proficiency assessment for the calculation of z U -scores rel. stanar eviation for proficiency assessment tolerance limits above an below permitte eviations above an below in % number of values in this level number of not satisfactory values below an above the assigne value an the percentage of these values in total. Determination of recovery rate In the iagrams of the assigne values versus the spike amount of analyte a linear regression line was calculate using a generalize least square regression which takes into account the uncertainties of the values in both irections. From these values the recovery rate for each parameter was etermine (see iagrams). The slope of the line inicates the average recovery rate. The iagrams also contain the expane uncertainty (k=2) of the concentrations from the spike an the assigne values. Relative stanar eviations an tolerance limits The iagrams for the relative stanar eviation vs. the assigne value show the concentration epenency of the stanar eviation an the tolerance limits in percent. The relative stanar eviations calculate from participants ata are the stars connecte by an interrupte line, the rel. stanar eviation taken from the variance function (an sometimes limite by the upper or lower limit) are given by squares, connecte by a continuous line.

8 PT 1/13 TW S1 page 5 Metho specific evaluation For each parameter the methos use by the participants are shown in a iagram. In a secon iagram for each metho with a frequency of more than 5 %, values are sorte in 5 categories: too low results with z U -score < -2 low results with 2 z U -score < 1 correct results with 1 z U -score +1 high results with +1 < z U -score +2 too high results with z U -score > +2 Comparison of means an reference values for each concentration level Finally the mean value calculate from all results, the reference value (see chapter Traceable reference values) are compare with mean values calculate for all methos separately. All mean values were calculate using the Hampel estimator escribe in ISO/TS Mean values were calculate only, if more than 8 results were within a z-score-range of ± 2. The means are reporte with their expane uncertainty, calculate accoring to ISO 128. All mean values an their expane uncertainties are aitionally compare with the reference values an their expane uncertainties. Explanation of Appenix B Participants were aske to report expane uncertainties of their results on a voluntary basis. In this iagram for each parameter the reporte uncertainties for all concentration levels with the reproucibility stanar eviation (horizontal line) are isplaye. Values which eviate from the reproucibility stanar eviation with a factor more than 2 are usually not realistic. Explanation of Appenix C In the last part of the report, for all concentration levels the results of all participants are illustrate. Confientiality of participants is ensure by using lab coes. The lab coes were sent to participants with the certificates. In etail Appenix C contains: - a table with all ata - figures with o all reporte results o all z U -scores o all reporte expane uncertainties o all ζ scores Table with all ata The assigne value with the expane uncertainty an the tolerance limits for the concentration level is illustrate in the table. For each participant the following ata are given: lab coe reporte result measurement uncertainty of the value (if reporte) ζ-score for this value, calculate with the following formula ζ = x x u 2 lab a + u 2 ref, with

9 PT 1/13 TW S1 page 6 x x a = ifference from the measure value an the assigne value u lab = stanar uncertainty of the value, reporte by the participant u ref = stanar uncertainty of the assigne value z U -score for proficiency assessment assessment of the value accoring to its z-score Meaning of ζ-scores: The assessment of ζ-scores is similar to that of z U -scores. If the ata are normally istribute an the uncertainties are well estimate, ζ-scores will lie between -2 an +2 with a probability of aroun 95 %. ζ-scores are mainly influence by the measurement uncertainties reporte by the laboratory. Therefore ζ-scores are usually not appropriate for the assessment of the reporte results, unless the reporte measurement uncertainty is checke for fitnessfor-purpose. Therefore we o not use the ζ-scores for the assessment of the laboratories. Nevertheless ζ-scores are appropriate to check the plausibility of the reporte measurement uncertainty: If the z U -score of a result is within the tolerance limit an the ζ-score is outsie, then the measurement uncertainty is unerestimate. If the z U -score is outsie the tolerance limits an the absolute value of the ζ-score is lower than two, then the requirements of the proficiency test were stronger compare with the reporte measurement uncertainty. Diagrams of uncertainty ata In the first figure for all lab coes the measurement uncertainty (together with the reproucibility stanar eviation) is illustrate. The secon figure shows the associate ζ-scores. Measurement uncertainty 10 (28,6%) out of laboratories with vali values reporte measurement uncertainties. In total 3 (30,96%) out of 591 vali values were given with the measurement uncertainty. The following table isplays the number of values with measurement uncertainty against the accreitation status. Accreitation status of the values Number of values Number of values with measurement uncertainty accreite (60,8%) not accreite 1 27 (20,5%) not specifie (8,9%) We woul like to put emphasis on the fact that reporting of measurement uncertainties in our PT scheme is absolutely voluntary. The only objective is to help all participants to reasonably hanle measurement uncertainties an their estimation. The iagrams show that the sprea of reporte uncertainties in some cases is vast, from unrealistic low values up to very high. A plausibility check using reproucibility stanar eviations of the PT roun coul be helpful here. If measurement uncertainties are unerestimate values assesse as satisfactory in the PT ( z U 2), will have a large ζ-score. ζ > 2 means that the own requirements (efine in terms of estimate uncertainty) are not fulfille. 31 (,3%) of the 161 values reporte with uncertainties an having a z U -score z U 2.0 ha a ζ-score > 2.0. This means that the requirements of the PT scheme have been fulfille, but not the own requirements, the uncertainty is unerestimate.

10 PT 1/13 TW S1 page 7 Traceable reference values Traceability of analytical results to national an international references is of increasing importance in all laboratories. This is not easy to realise for chemical analyses an often can only be one by analysing certifie reference materials. But availability of these reference materials in the water sector is very limite. Therefore we try to provie reference values for the proficiency test samples, traceable to national an international references. Since our PT samples without exception are spike, real water samples, reference values can be calculate from the sum of matrix content an spike amount of analyte. For both summans traceable values an their uncertainty have to be etermine. Thereby we assume that no unrecognise bias resulting from sample preparation an transport is present an that we recognise all uncertainty components. All spiking of samples was controlle gravimetrically an volumetrically. This proceure allows the preparation of a complete uncertainty buget. The first step is the specification of the measuran with a formula. This shows the links between the result an all influence quantities for the parameter. with: c lot m ss V 1 V 2 V lot V ss V 1_total V 2_total m lot_total ρ lot P concentration of the analyte in the lot resulting from the spike mass of substance ae for preparation of the stock solution volume of stock solution ae into the ilution A volume of ilution A ae into the ilution B volume of ilution B ae into the lot volume of stock solution total volume of ilution A total volume of ilution B total mass of the lot ensity of the lot in g/l purity of the use substance Base on this formula the uncertainty buget can be prepare an all components can be quantifie. The following figure shows a typical istribution of the contributions for saccharin. The main contributions result from the purity of the chemical an the pipette steps.

11 PT 1/13 TW S1 page 8 Attention was pai to use a groun water which i not contain any analyte. Therefore no matrix content ha to be consiere an the reference values coul be calculate irectly from the spikes. Internet The report is available on the following webpage:

12 acesulfam level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,24 1,65 0,09 0, ,59 0,3115 0,1647,02-29, ,0 2 2,440 1,65 0,5081 0, ,89 3,591 1,506 47,13-38, ,5 3 4,706 1,65 0,7922 0, ,77 6,441 3,239 36,86-31, ,5 sum ,3 out [%] Recovery an matrix content e n e n Slope of the regression: 1,002, recovery: 100,2% Page A-1 of 48

13 Relative stanar eviation an tolerance limits l n The relative stanar eviation, calculate with the Q-metho, i not reach the limits. e l n Page A-2 of 48

14 Metho specific evaluation e e e e e >D^ >D^ K e l e LC-MS - extraction LC-MS - irect injection The values, etermine after extraction, showe a broaer statistical istribution an a higher ratio of outliers. Page A-3 of 48

15 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,2302 0,0161 7,0 0,24 0,0038 1,7 2 2,4 0,228 9,4 2,440 0,040 1,7 3 4,723 0,6 7,5 4,706 0,078 1,7 >D^ n Page A-4 of 48

16 >D^ n >D^ e n Page A-5 of 48

17 l >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,23 0,009 4,042 0,0 15, , ,424 0,1 4,11 0,374 15, , ,673 0,16 3,426 0,614 13, ,74 robust stanar eviation [%] number of results out below out above out [%] Page A-6 of 48

18 cyclamat level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,1670 1,65 0,0297 0,0303,16 0,22 0, ,26-33, ,1 2 0,8015 1,65 0,1312 0, ,16 1,085 0,5602,37-30, ,4 3 1,710 1,65 0,2646 0, ,26 2,278 1,222 33,21-28, ,4 sum ,7 out [%] Recovery an matrix content e e n e e e e e e n Slope of the regression: 1,05, recovery: 102% Page A-7 of 48

19 Relative stanar eviation an tolerance limits l e e e e n The relative stanar eviation, calculate with the Q-metho, i not reach the limits. l e e e e n Page A-8 of 48

20 Metho specific evaluation e e eee e e e >D^ >D^ K e l e LC-MS - extraction LC-MS - irect injection The ifferences between the methos were not significant. Page A-9 of 48

21 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,1636 0,0143 8,7 0,1670 0,0028 1,7 2 0,8120 0,0631 7,8 0,8015 0,0133 1,7 3 1,7 0,127 7,3 1,710 0,028 1,7 e e n e e >D^ Page A-10 of 48

22 >D^ e e e e n >D^ e e n e e Page A-11 of 48

23 e e e l e e e >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,165 0,008 5,039 0,028 17, ,11 2 0,803 0,039 4,816 0,131 16, 0 1 5, ,769 0,082 4,62 0,285 16, ,263 robust stanar eviation [%] number of results out below out above out [%] Page A-12 of 48

24 saccharin level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,2056 1,66 0,0453 0, ,58 0,3061 0, ,92-39, ,2 2 0,91 1,66 0,1427 0,14 15, 1,2 0, ,42-28, ,2 3 1,850 1,66 0,3626 0,88,39 2,652 1,9 43,33 -, ,8 sum ,7 out [%] Recovery an matrix content n n Slope of the regression: 1,0047, recovery: 100,5% Page A-13 of 48

25 Relative stanar eviation an tolerance limits l e e e e n The relative stanar eviation, calculate with the Q-metho, i not reach the limits. e l e e e e n Page A-14 of 48

26 Metho specific evaluation e eeee e ee e >D^ >D^ K e l e LC-MS - extraction LC-MS - irect injection The values, etermine after extraction, showe a broaer statistical istribution. Page A-15 of 48

27 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,2099 0, ,6 0,2056 0,00 1,7 2 0,9300 0,0700 7,5 0,91 0,0153 1,7 3 1,869 0,178 9,5 1,850 0,031 1,7 >D^ n Page A-16 of 48

28 >D^ e n e >D^ n Page A-17 of 48

29 l >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,208 0,013 6,157 0,042 20, , ,913 0,0 3,869 0,117 12, ,65 3 1,884 0,086 4,557 0,291 15, ,11 robust stanar eviation [%] number of results out below out above out [%] Page A- of 48

30 sucralose level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,37 1,94 0,0626 0,0624,53 0,4593 0, ,67 -, ,0 2 1,599 1,94 0,28 0, ,45 2,099 1,165 31,29-27, ,0 3 2,877 1,94 0,3097 0,21 11,20 3,562 2,265 23,79-21, ,0 sum ,0 out [%] Recovery an matrix content n n Slope of the regression: 0,9610, recovery: 96,1% Page A- of 48

31 Relative stanar eviation an tolerance limits l n The relative stanar eviation, calculate with the Q-metho, i not reach the limits. l n Page A-20 of 48

32 Metho specific evaluation e e e >D^ >D^ K e l e LC-MS - extraction LC-MS - irect injection The values, etermine after extraction, showe a broaer statistical istribution an a higher ratio of too high values. Page A-21 of 48

33 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,06 0,0313 9,8 0,37 0,0062 1,9 2 1,563 0,113 7,2 1,599 0,031 1,9 3 2,766 0,155 5,6 2,877 0,056 1,9 n >D^ Page A-22 of 48

34 >D^ e e n e e >D^ n Page A-23 of 48

35 l >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,6 0,014 4,143 0,043 13, ,75 2 1,527 0,064 4,178 0,204 13, , 3 2,817 0,105 3,711 0,3 11, ,75 robust stanar eviation [%] number of results out below out above out [%] Page A-24 of 48

36 1H-benzotriazole level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,1224 1,70 0,0174 0, ,24 0,1601 0, ,81-26, ,9 2 0,6883 1,70 0,0786 0, ,22 0,8681 0, ,12-23, ,9 3 1,927 1,70 0,58 0, ,78 2,367 1,5 22,84-20, ,4 sum ,0 out [%] Recovery an matrix content, n n Slope of the regression: 0,94, recovery: 93,2% Page A- of 48

37 Relative stanar eviation an tolerance limits, l n The relative stanar eviation, calculate with the Q-metho, i not reach the limits., l n Page A-26 of 48

38 Metho specific evaluation, e e eeee e eee e >D^ >D^ K, e l e LC-MS - extraction LC-MS - irect injection The values, etermine with LC-MS - irect injection, showe the closest istribution. Page A-27 of 48

39 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,1221 0,0082 6,7 0,1224 0,0021 1,7 2 0,6433 0,0371 5,8 0,6883 0,0117 1,7 3 1,817 0,093 5,1 1,927 0,033 1,7 >D^ n e e Page A-28 of 48

40 >D^ e e e n >D^ n Page A-29 of 48

41 e l e e >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,123 0,003 2,675 0,011 9, ,53 2 0,647 0,0 2,729 0,062 9, ,79 3 1,856 0,039 2,101 0,136 7, ,79 robust stanar eviation [%] number of results out below out above out [%] Page A-30 of 48

42 4-methyl-1H-benzotriazole level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,2015 2,12 0,0280 0, ,97 0,76 0, ,84-24, ,5 2 0,73 2,12 0,0788 0,07 10,00 0,8782 0, ,09 -, ,4 3 1,451 2,12 0,1307 0,1230 8,48 1,708 1,214 17,74-16, ,6 sum ,5 out [%] Recovery an matrix content e e n e e, e e e n Slope of the regression: 1,0704, recovery: 107% Page A-31 of 48

43 Relative stanar eviation an tolerance limits, l e e e n The relative stanar eviation, calculate with the Q-metho, i not reach the limits., l e e e n Page A- of 48

44 Metho specific evaluation, e ee e ee >D^ >D^ K, e l LC-MS - extraction LC-MS - irect injection The ifferences between the methos were not significant. Page A-33 of 48

45 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,2161 0,0170 7,9 0,2015 0,0043 2,1 2 0,7881 0,0478 6,1 0,73 0,0153 2,1 3 1,541 0,079 5,1 1,451 0,031 2,1 >D^ n Page A- of 48

46 >D^ e e e e n >D^ e e n e e Page A- of 48

47 l e e >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,217 0,009 4,146 0, ,27 2 0,79 0,037 4,724 0,099 12, , ,565 0,04 2,548 0,106 6, , robust stanar eviation [%] number of results out below out above out [%] Page A-36 of 48

48 5-methyl-1H-benzotriazole level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,1490 1,71 0,01 0,01 9,07 0,1773 0,1231,04-17, ,3 2 0,6704 1,71 0,0458 0,0452 6,75 0,7641 0, ,98-13, ,2 3 1,460 1,71 0,2153 0, ,77 1,928 1,056,05-27, ,5 sum ,3 out [%] Recovery an matrix content e e n e e, e e e n Slope of the regression: 1,01, recovery: 101,2% Page A-37 of 48

49 Relative stanar eviation an tolerance limits, l e e e n The relative stanar eviation, calculate with the Q-metho, i not reach the limits., l e e e n Page A-38 of 48

50 Metho specific evaluation, e ee e ee >D^ >D^ K, e l e LC-MS - extraction LC-MS - irect injection The ifferences between the methos were not significant. Page A-39 of 48

51 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,1492 0,0082 5,5 0,1490 0,00 1,7 2 0,6792 0,0278 4,1 0,6704 0,0114 1,7 3 1,458 0,131 9,0 1,460 0,0 1,7 e e n e e >D^ Page A-40 of 48

52 >D^ e e e n >D^ e e n e e Page A-41 of 48

53 e l e e >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,151 0,005 3,591 0,014 9, ,27 3 1,475 0,072 4,848 0, 12, ,091 robust stanar eviation [%] number of results out below out above out [%] Page A-42 of 48

54 sum _methylbenzotriazole level assigne value [µg/l] expane uncertainty of the assigne value [%] stanar eviation, calculate using robust statistics [µg/l] stanar eviation for proficiency assessment [µg/l] stanar eviation for proficiency assessment [%] upper tolerance limit [µg/l] lower tolerance limit [µg/l] upper tolerance limit [%] lower tolerance limit [%] number of results out below out above 1 0,04 1,42 0,0703 0, ,42 0,5114 0,22 45,92-37, ,0 2 1,396 1,37 0,21 0,22 15,89 1,880 0,9820,72-29, ,8 3 2,911 1,36 0,3627 0, ,66 3,701 2,214 27,14-23, ,5 sum ,1 out [%] Recovery an matrix content n n Slope of the regression: 0,9839, recovery: 98,4% Page A-43 of 48

55 Relative stanar eviation an tolerance limits l n The relative stanar eviation, calculate with the Q-metho, i not reach the limits. e l n Page A-44 of 48

56 Metho specific evaluation e e ee e e e >D^ >D^ K e l e LC-MS - extraction LC-MS - irect injection The values, etermine with LC-MS after extraction, showe a higher ratio of too low values. Page A-45 of 48

57 Comparison of means an reference values level mean [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] reference value [µg/l] exp. uncertainty [µg/l] exp. uncertainty [%] 1 0,45 0,05 10,0 0,04 0,0050 1,4 2 1,372 0,107 7,8 1,396 0,0 1,4 3 2,864 0,178 6,2 2,911 0,040 1,4 n >D^ Page A-46 of 48

58 >D^ e n e e >D^ n Page A-47 of 48

59 l >D^ LC-MS - irect injection level robust mean [µg/l] exp. unc. of the mean [µg/l] exp. unc. of the mean [%] robust stanar eviation [µg/l] 1 0,4 0,017 4,801 0,056 16, ,11 2 1,396 0,069 4,977 0,236 16, , ,962 0,083 2,812 0,283 9, ,22 robust stanar eviation [%] number of results out below out above out [%] Page A-48 of 48

60 el l l l l l l l l l l l l l l l Page B-1 of B-4

61 el el l l l l l l el el el l l l l l l Page B-2 of B-4

62 , l l l l l l l l D, l l l l l l Page B-3 of B-4

63 D, l l l l l l l D l l l l l l Page B-4 of B-4

64 assigne value [µg/l]* upper tolerance limit [µg/l] acesulfam - 1 0,24 0,3115 ± 0,0038 lower tolerance limit [µg/l] 0,1647 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 0,227-0, ,2-1, ,22-0, ,2-0, ,2 0, ,13-3,0-11 0,216-0, ,233 0,033 0,0 0, ,268 0, ,28 0,1 1,0 1, ,203-0,9 + 0,266 0,04 1,7 0,8 + 0,229 0,046-0,1-0, ,275 1, ,267 0, ,243 0, , -0,4 + 0,243 0,009 2,2 0, ,282 1, ,9 0,7 + 0,169 0,004-22,9-1, ,249 0,06 0,6 0,4 + 0,217 0,04-0,8-0,5 + 0,213 0,033-1,2-0, ,373 3,6-38 0,442 5,3-39 0,3-1, ,229-0, ,233 0, ,136-2,8-46 0,213-0,6 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-1 of C-72

65 n e h Page C-2 of C-72

66 n e e ^ ζ Page C-3 of C-72

67 assigne value [µg/l]* upper tolerance limit [µg/l] acesulfam - 2 2,44 3,591 ± 0,04 lower tolerance limit [µg/l] 1,506 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 2,288-0, ,03-0, ,28-0, ,38-0, ,38-0, ,15-2,8-11 2,1-0, ,54 0,36 0,6 0, ,79 0, ,2 2,1 1,7 3,1-16 2,08-0,8 + 2,84 0,426 1,9 0,7 + 2,311 0,462-0,6-0, ,796 0, ,98 0, ,55 0, ,436 0,0 + 2,561 0,061 3,3 0, ,979 0, ,27-2,5-1,76 0,042-23,4-1, ,45 0,61 0,0 0,0 + 2,414 0,58-0,1-0,1 + 2,3 0,7-0,8-0, ,87 2,5-38 4,02 2,7-39 2,03-0, ,36-0, ,58 0, ,286-4,6-46 2,27-0,4 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-4 of C-72

68 n h Page C-5 of C-72

69 n ^ ζ Page C-6 of C-72

70 assigne value [µg/l]* upper tolerance limit [µg/l] acesulfam - 3 4,706 6,441 ± 0,078 lower tolerance limit [µg/l] 3,239 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 4,431-0, ,06-0, ,51-0, ,55-0, ,73 0, ,33-3,2-11 4, -0, ,85 0,68 0,4 0, ,37 0, ,3 2,8 1,9 3,0-16 3,78-1,3 + 5,12 0,768 1,1 0,5 + 4,509 0,902-0,4-0, ,457 2, ,88 1, ,77 0, ,72 0,0 + 4,841 0,15 1,6 0, ,841 1, ,78-4,0-3,41 0,042-29,3-1, ,62 1,16-0,1-0,1 + 4,53 0,38-0,9-0,2 + 4,42 0,686-0,8-0, ,11 1, ,48 3,2-39 3,55-1, ,69 0, ,87 0, ,488-5,7-46 4,61-0,1 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-7 of C-72

71 e e e n e e h Page C-8 of C-72

72 n ^ ζ Page C-9 of C-72

73 assigne value [µg/l]* upper tolerance limit [µg/l] cyclamat - 1 0,167 0,22 ± 0,0028 lower tolerance limit [µg/l] 0,1109 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 0,152-0, ,15-0, ,175 0, , 0, ,156-0, ,7 0, ,17 0,04 0,2 0, ,171 0,1 + 0,1 0,02-3,1-1,1 + 0,095 0,0-5,7-2,6-20 0,1 0, ,8 0, ,163-0, ,1645-0,1 + 0,136 0,012-5,0-1, ,204 1, ,7 2,7-0,154 0,007-3,4-0, ,16 0,04-0,3-0,2 + 0,157 0,02-1,0-0,4 + 0,164 0,047-0,1-0, ,276 3,2-38 0,123-1, ,176 0, ,147-0, ,158-0, ,055-4,0 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-10 of C-72

74 n h Page C-11 of C-72

75 n ^ ζ e e Page C-12 of C-72

76 assigne value [µg/l]* upper tolerance limit [µg/l] cyclamat - 2 0,8015 1,085 ± 0,0133 lower tolerance limit [µg/l] 0,5602 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 0,692-0, ,66-1, ,794-0, ,07 1, ,774-0, ,87 0, ,88 0,3 0,5 0, ,674-1,1 + 0,9 0,14 1,9 0,9 + 0,664 0,173-1,6-1, ,829 0, ,898 0, ,746-0, ,8005 0,0 + 0,658 0,039-6,9-1, ,965 1, ,861 0,4 + 0,771 0,016-2,9-0, ,76 0, -0,4-0,3 + 0,75 0,04-2,4-0,4 + 0,723 0,205-0,8-0, ,2 2,8-38 0,847 0, ,815 0, ,86 0, ,867 0, ,209-4,9 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-13 of C-72

77 e e n e h Page C-14 of C-72

78 n ^ ζ e e e Page C-15 of C-72

79 assigne value [µg/l]* upper tolerance limit [µg/l] cyclamat - 3 1,71 2,278 ± 0,028 lower tolerance limit [µg/l] 1,222 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 1,478-1, ,48-0, ,69-0, ,13 1, ,61-0, ,87 0, ,7 0,5 0,0 0, ,69-0,1 + 1,91 0,287 1,4 0,7 + 1,362 0,4-2,0-1, ,966 0, , ,57-0, ,7015 0,0 + 1,436 0,067-7,5-1, ,5 1, ,56-0,6 + 1,62 0,067-2,5-0, ,7 0,43 0,0 0,0 + 1,608 0,14-1,4-0,4 + 1,59 0,451-0,5-0, ,12 1, , 2,1-39 1,63-0, ,85 0, ,56-0, ,524-4,9 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-16 of C-72

80 n e h Page C-17 of C-72

81 e n ^ ζ e e Page C- of C-72

82 assigne value [µg/l]* upper tolerance limit [µg/l] saccharin - 1 0,2056 0,3061 ± 0,00 lower tolerance limit [µg/l] 0,1245 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 0, -0, , -0, ,203-0, ,27 1, ,151-1, ,249 0, ,27 0,09 1,4 1, ,216 0,2 + 0,205 0,031 0,0 0,0 + 0,4 0,074 1,3 1, ,298 1, ,169-0, ,2055 0,0 + 0,145 0,023-5,2-1, ,2-0, ,9-0,2 + 0,169 0,005-12,1-0, ,238 0,08 0,8 0,6 + 0,175 0,04-1,5-0,8 + 0,224 0,038 1,0 0, ,26 1, ,2 0, ,4-0, ,7-0, ,3 0, ,071-3,3 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C- of C-72

83 n h Page C-20 of C-72

84 e e n e e ^ ζ e e Page C-21 of C-72

85 assigne value [µg/l]* upper tolerance limit [µg/l] saccharin - 2 0,91 1,2 ± 0,0153 lower tolerance limit [µg/l] 0,6598 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 0,905-0, ,88-0, ,921 0, ,2 1, ,817-0, ,947 0, ,5 0,9 1,3 3,7-16 0,816-0, ,015 7,0 0,5 + 0,99 0,287 0,5 0, ,4 1, ,872-0, ,914-0,1 + 0,698 0,067-6,6-1, ,8-0, ,774-1,1 + 0,828 0,016-8,8-0, ,969 0, 0,3 0,3 + 0,789 0,14-1,9-1,0 + 0,951 0,162 0,3 0, ,17 1, ,11 1, ,873-0, ,983 0, ,936 0, ,229-5,2 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-22 of C-72

86 e e e n e h Page C-23 of C-72

87 e e n e e e e ^ ζ e e Page C-24 of C-72

88 assigne value [µg/l]* upper tolerance limit [µg/l] saccharin - 3 1,85 2,652 ± 0,031 lower tolerance limit [µg/l] 1,9 lab coe result [µg/l] ± ζ-score z U -score assessm. 1 1,78-0, , ,86 0, ,09 0, ,43-1, ,63 1, ,3 1,1 2,6 3,6-16 1,54-0,9 + 1,9 0,285 0,3 0,1 + 2,07 0,6 0,7 0, ,687 2,1-21 1,77-0, ,873 0,1 + 1,46 0,114-6,6-1, ,705-0, ,47-1,2 + 1,67 0,057-5,6-0, ,88 0,66 0,1 0,1 + 1,598 0, -2,8-0,8 + 1,87 0,3 0,1 0, ,24 1, ,22 0, ,87 0, ,77-0, ,94 0, ,405-4,4 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C- of C-72

89 n h Page C-26 of C-72

90 n e e ^ ζ e e Page C-27 of C-72

91 assigne value [µg/l]* upper tolerance limit [µg/l] sucralose - 1 0,37 0,4593 ± 0,0062 lower tolerance limit [µg/l] 0,2048 lab coe result [µg/l] ± ζ-score z U -score assessm. 2 0,22-1, ,145-3,0-5 0,271-0, ,305-0, ,1 0, ,29 0,2-0,3-0, ,8 0,4 + 0,2 0,051 0,9 0,3 + 0,3 0,076 0,3 0, ,36 0, ,272-0, ,393 1, ,15 0,0 + 0,9 0,056 0,3 0, ,447 1, ,236-1,5 + 0,333 0,003 3,9 0, ,339 0,1 0,4 0,3 + 0, 0,08 0,5 0,3 + 0,274 0,089-1,0-0, ,3 0, ,382 0, ,305-0, ,398 1, ,974 9,4 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-28 of C-72

92 e n e e e h Page C-29 of C-72

93 n ^ ζ Page C-30 of C-72

94 assigne value [µg/l]* upper tolerance limit [µg/l] sucralose - 2 1,599 2,099 ± 0,031 lower tolerance limit [µg/l] 1,165 lab coe result [µg/l] ± ζ-score z U -score assessm. 2 1,27-1, ,686-4,2-5 1,39-1, ,43-0, ,42-0, ,9 0,5 1,2 1, ,73 0,5 + 1,64 0,246 0,3 0,2 + 1,404 0,3-1,2-0, ,574-0, , -1, ,87 1, ,64 0,2 + 1,478 0,141-1,7-0, ,7 0, ,57-0,1 + 1,58 0,106-0,3-0, ,52 0,46-0,3-0,4 + 1,641 0,48 0,2 0,2 + 1,42 0,458-0,8-0, ,45-0, ,67 0, ,53-0, ,13 2,1-45 5,276 14,7 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-31 of C-72

95 e n h Page C- of C-72

96 e n ^ ζ Page C-33 of C-72

97 assigne value [µg/l]* upper tolerance limit [µg/l] sucralose - 3 2,877 3,562 ± 0,056 lower tolerance limit [µg/l] 2,265 lab coe result [µg/l] ± ζ-score z U -score assessm. 2 2,8-0, ,1-2,5-5 2,43-1, ,46-1, ,08 0, ,8 0,7-0,2-0, ,89 0,0 + 3,04 0,456 0,7 0,5 + 2,757 0,6-0,4-0, ,026 0, ,62-0, ,62 2,2-24 2,8955 0,1 + 2,666 0,139-2,8-0, ,282 1, ,7-0,6 + 2,82 0,104-1,0-0, ,59 0,78-0,7-0,9 + 2,748 0,38-0,7-0,4 + 2,57 0,83-0,7-1, ,96 0, ,97-3,0-43 2,69-0, ,78-0, ,0 17,9 - * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C- of C-72

98 e e e e n h Page C- of C-72

99 e e e n e ^ ζ Page C-36 of C-72

100 assigne value [µg/l]* upper tolerance limit [µg/l] 1H-benzotriazole - 1 0,1224 ± 0,0021 0,1601 lower tolerance limit [µg/l] 0,08965 lab coe result [µg/l] ± ζ-score z U -score assessm. 2 0,1-1, ,122 0, ,121-0, ,136 0, ,53 21,6-10 0,11-0, ,129 0,02 0,7 0, ,133 0, ,066 0,003-30,9-3,4-0,123 0,0 0,1 0,0 + 0,129 0,026 0,5 0, ,141 1, ,131 0, ,1 0,1 + 0,128 0,007 1,6 0, ,144 1, ,11-0, ,264 7,5-0,129 0,007 1,8 0,4 + 0,129 0,04 0,3 0,4 + 0,1 0,015 1,7 0, ,106-1, ,13 0, ,139 0, ,0865-2,2-44 0,1-0, ,1-1, ,111-0,7 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-37 of C-72

101 e n, h, Page C-38 of C-72

102 , n 17 12, ^ ζ ee Page C-39 of C-72

103 assigne value [µg/l]* upper tolerance limit [µg/l] 1H-benzotriazole - 2 0,6883 ± 0,0117 0,8681 lower tolerance limit [µg/l] 0,5292 lab coe result [µg/l] ± ζ-score z U -score assessm. 2 0,55-1, ,668-0, ,685 0, ,683-0, ,6-1, ,54-1, ,683 0,1-0,1-0, ,659-0, ,472 0,02 -,7-2,7-0,631 0,095-1,2-0,7 + 0,633 0,127-0,9-0, ,742 0, ,669-0, ,69 0,0 + 0,663 0,097-0,5-0, ,788 1, ,62-0, ,544-1,8 + 0,685 0,014-0,4 0,0 + 0,623 0,04-3,1-0,8 + 0,64 0,072-1,3-0, ,9 2,4-38 0,692 0, ,691 0, ,464-2,8-44 0,611-1, ,054-8,0-46 0,612-1,0 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-40 of C-72

104 e e e e n, e e h, Page C-41 of C-72

105 , n e e 17 12, ^ ζ Page C-42 of C-72

106 assigne value [µg/l]* upper tolerance limit [µg/l] 1H-benzotriazole - 3 1,927 ± 0,033 2,367 lower tolerance limit [µg/l] 1,5 lab coe result [µg/l] ± ζ-score z U -score assessm. 2 1,83-0, ,07 0, ,93 0, ,68-1, , -3,1-10 1,55-1, ,89 0,28-0,3-0, ,89-0, ,41 0,07-13,4-2,6-1,8 0,27-0,9-0,6 + 1,813 0,363-0,6-0, ,0 0, ,9-0, ,9015-0,1 + 1,904 0,158-0,3-0, ,09 0, ,82-0, ,84-5,5-1,92 0,07-0,2 0,0 + 1,816 0,3-0,7-0,6 + 1,85 0,208-0,7-0, ,92 0, ,88-0, ,7-1, ,09-4,2-44 1,67-1, ,2-8,6-46 1,68-1,3 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-43 of C-72

107 n, e e h, Page C-44 of C-72

108 , n 17 12, ^ ζ e e e Page C-45 of C-72

109 assigne value [µg/l]* upper tolerance limit [µg/l] 4-methyl-1H-benzotriazole - 1 0,2015 ± 0,0043 0,76 lower tolerance limit [µg/l] 0,1522 lab coe result [µg/l] ± ζ-score z U -score assessm. 4 0,208 0, ,238 1, ,223 0, ,2 0,03 1,1 0, ,236 1, ,145 0,007-13,8-2,3-0,21 0,0 0,5 0,3 + 0,217 0,043 0,7 0, ,22 0, ,2245 0,8 + 0,175 0,012-4,3-1, ,245 1,6 + 0,285 0,06 2,8 3,0-0,22 0,03 1,2 0, ,237 1, ,167-1, ,6-0,2 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-46 of C-72

110 , n , h Page C-47 of C-72

111 , e e n 17 12, ^ ζ e e e Page C-48 of C-72

112 assigne value [µg/l]* upper tolerance limit [µg/l] 4-methyl-1H-benzotriazole - 2 0,73 ± 0,0153 0,8782 lower tolerance limit [µg/l] 0,5868 lab coe result [µg/l] ± ζ-score z U -score assessm. 4 0,766 0, ,758 0, ,87 1, ,786 0,12 1,0 0, ,841 1, ,41 0,02 -,0-4,6-0,73 0,11 0,1 0,1 + 0,738 0,148 0,2 0, ,898 2,3-24 0,8105 1,1 + 0,741 0,004 2,0 0, ,812 1,1 + 0,784 0,04 2,7 0,8 + 0,768 0,104 0,8 0, ,96 3,1-43 0,657-1, ,731 0,1 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-49 of C-72

113 , e n e , h Page C-50 of C-72

114 , e n e e 17 12, ^ ζ Page C-51 of C-72

115 assigne value [µg/l]* upper tolerance limit [µg/l] 4-methyl-1H-benzotriazole - 3 1,451 ± 0,031 1,708 lower tolerance limit [µg/l] 1,214 lab coe result [µg/l] ± ζ-score z U -score assessm. 4 1,56 0, ,53 0, , -1, ,57 0,24 1,0 0, ,66 1, ,849 0,04-23,9-5,1-1,47 0,221 0,2 0,2 + 1,488 0,298 0,3 0, ,655 1, ,61 1,3 + 1,524 0,114 1,2 0, ,669 1,7 + 1,667 0,1 4,1 1,7 + 1,54 0,209 0,8 0, ,6 1, ,27-1, ,42-0,3 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-52 of C-72

116 , e e n e e , h e Page C-53 of C-72

117 , n 17 12, ^ ζ ee Page C-54 of C-72

118 assigne value [µg/l]* upper tolerance limit [µg/l] 5-methyl-1H-benzotriazole - 1 0,149 ± 0,00 0,1773 lower tolerance limit [µg/l] 0,1231 lab coe result [µg/l] ± ζ-score z U -score assessm. 4 0,069-6,2-5 0,144-0, ,137-0, ,155 0,02 0,6 0, ,148-0, ,06 0,003-45,3-6,9-0,148 0,022-0,1-0,1 + 0,152 0,03 0,2 0, ,166 1, ,15 0,1 + 0,244 0,029 6,4 6,7-29 0,158 0,6 + 0,14 0,04-0,4-0,7 + 0,146 0,0-0,3-0, ,146-0, ,0755-5,7-44 0,149 0,0 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-55 of C-72

119 , n , e e h e e Page C-56 of C-72

120 , n 17 12, e e ^ ζ e e Page C-57 of C-72

121 assigne value [µg/l]* upper tolerance limit [µg/l] 5-methyl-1H-benzotriazole - 2 0,6704 ± 0,0114 0,7641 lower tolerance limit [µg/l] 0,5828 lab coe result [µg/l] ± ζ-score z U -score assessm. 4 0,44-5,3-5 0,671 0, ,747 1, ,683 0,1 0,3 0, ,649-0, ,291 0,02 -,9-8,7-0,664 0,01-0,8-0,1 + 0,654 0,131-0,2-0, ,72 1, ,6705 0,0 + 1,052 0,033 22,2 8,1-29 0,67 0,0 + 0,669 0,16 0,0 0,0 + 0,644 0,082-0,6-0, ,83 3,4-43 0,33-7,8-44 0,654-0,4 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-58 of C-72

122 , e n e , e e h e e Page C-59 of C-72

123 , e e n e e D, ^ ζ e Page C-60 of C-72

124 assigne value [µg/l]* upper tolerance limit [µg/l] 5-methyl-1H-benzotriazole - 3 1,46 ± 0,0 1,928 lower tolerance limit [µg/l] 1,056 lab coe result [µg/l] ± ζ-score z U -score assessm. 4 1,16-1, ,36-0, ,73 1, ,47 0,22 0,1 0, ,45 0, ,682 0,03-39,9-3,9-1,46 0,2 0,0 0,0 + 1,443 0,289-0,1-0, ,571 0, ,46 0,0 + 1,706 0,2 2,2 1, ,5 0,3 + 1,367 0,28-0,7-0,5 + 1,49 0,9 0,3 0, ,63 0, ,454-5,0-44 1,24-1,1 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-61 of C-72

125 , n , h e Page C-62 of C-72

126 , n 17 12, ^ ζ e Page C-63 of C-72

127 assigne value [µg/l]* upper tolerance limit [µg/l] sum _methylbenzotriazoles - 1 0,04 ± 0,005 0,5114 lower tolerance limit [µg/l] 0,22 lab coe result [µg/l] ± ζ-score z U -score assessm. 2 0,28-1, ,382 0, ,3-0, ,3-0, ,373 0,06 0,7 0, ,384 0, ,226 0,01-22,3-1,9 + 0,8 0,1 + 0,369 0,074 0,5 0, ,386 0, ,313-0, ,3745 0,3 + 0,4 0,041 3,3 0, ,403 0, ,29-0, ,514 2,0 + 0,3 0,004-52,5-2,6-0,4 0,1 1,5 0,9 + 0,366 0, ,383 0, ,313-0, ,338-0, ,243-1, ,5-0, ,05-4,6-46 0,362 0,1 + * The state uncertainty of the assigne value is the expane uncertainty with a coverage factor k=2 corresponing to a confience level of about 95% Page C-64 of C-72

128 e n h Page C-65 of C-72