177 
Table 70: Absolute recoveries of the analytes; addition of ISTD after extraction and elution [%] in sea 
water samples 
Analyte 
Recovery [%] 
Chlorpyrifos-ethyl 
94 
Chlorpyrifos-methyl 
109 
Endosulfan I 
88 
Endosulfan II 
99 
Trifluralin 
81 
Sediment samples 
Relative and absolute recoveries of the analytes in sediment samples are shown in Table 
71 and Table 72, respectively. Both relative and absolute recoveries are sufficiently 
high. The standard deviations are satisfactory. 
Table 71: Relative recoveries of the analytes (spike experiments with a concentration of 0.2 pg/kg (one 
experiment) and 4 pg/kg (average of 5 experiments) in sediment samples 
Analyte 
Recovery [%] 0.2 pg/kg 
Recovery [%] (M±STD) 4 pg/kg 
Chlorpyrifos-ethyl 
118 
85+12 
Chlorpyrifos-methyl 
63 
86+12 
Endosulfan I 
82 
93±3 
Endosulfan II 
111 
87±11 
Trifluralin 
87 
94±9 
Table 72: Absolute recoveries [%] of the ISTD referred to D 6 -Chlorpyrifos-methyl as recovery standard 
(7 experiments; concentration of ISTD 0.2 pg/kg) in sediment samples; addition of the recovery standard 
(0.004 ng/pL) after extraction and elution 
Analyte 
Recovery [%] (M±STD) 
D ! o-Chlorpyrifos-ethyl 
74±11 
D 4 -Endosulfan I 
80+11 
D 14 -Trifluralin 
74±10