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179 6.3.3.4 Limits of quantification Table 75 to Table 77 show the limits of quantification (LOQ) of the analytes in the different matrices. LOQ are calculated for a signal-to-noise ratio (S/N) of 9; the limits of detection (LOD) are calculated for an S/N ratio of 3. Table 75: Limits of quantification of the analytes [pg/L] in sea water samples Analyte Limit of Quantification [pg/L] Chlorpyrifos-ethyl 10 Chlorpyrifos-methyl 10 Endosulfan I 20 Endosulfan II 20 Trifluralin 7 Dicofol 1000 PCP 200 TCPy 400 As shown in Table 76, the LOQs for sediments were improved during the project by increasing the amount of sediment sample and increasing the polarity of the extraction solvent. In this way, different samples may have partly different LOQs. Table 76: Comparison of LOQs of the analytes [ng/g dw] in sediment samples for different sample amounts (20 and 40 g of sediment) and different solvents (Solvent: A: acetone/hexane 50/50; B; acetone/ hexane 75/25. MAE; 10 min, 100°C, 700 W) Analyte LOQ (20 g sediment) [ng/g] A a LOQ (40 g sediment) [ng/g] A b LOQ (40 g sediment) [ng/g] B c Trifluralin 0.005 0.003 0.0006 Chlorpyrifos- methyl 0.034 0.025 0.023 Chlorpyrifos- ethyl 0.017 0.009 0.007 Endosulfan I 0.024 0.010 0.011 Endosulfan II 0.061 0.030 0.014 a GA371, GA387, GA402 and GA405; b GA419; C GA421. The LOQs for biota vary depending on the particular fish species (Table 77) and are due primarily to different amounts of lipid and matrix background levels in the three fish species studied.