46 / 71
1442
Pang et al.:
J
ournal of
AOAC I
nternational
V
ol.
98, N
o.
5, 2015
Table 6. Method efficiency for the determination of 20 pesticides in fortified tea samples by LC/MS/MS (24 laboratories)
Green tea
Oolong tea
Avg. C.,
μg/kg
Rec., %
Avg.
rec., %
S
r
,
μg/kg RSD
r
, %
S
R
,
μg/kg RSD
R
, % HorRat
Avg. C., μg/
kg
Rec. %
No.
Pesticide
No. of
labs No. 1 No. 2
Avg. C.,
μg/kg No. 1 No. 2
No. of
labs` No.6 No.7
Avg. C.,
μg/kg No.6 No.7
Avg.
rec., %
S
r
,
μg/kg RSD
r
, %
S
R
,
μg/kg
RSD
R
,
% HorRat
1
Acetochlor
20 37.9 37.6 37.9 94.8 94.0 94.4 2.2 5.7
3.2
8.4
0.3
23 18.1 18.3 18.2 90.6 91.6 91.1 1.1 6.2 4.0 21.7 0.7
2
Benalaxyl
22 19.3 19.7 19.5 96.6 98.7 97.7 1.3 6.7
2.3 12.0 0.4
23 9.0 9.1 9.0 90.2 90.8 90.5 0.5 5.8 1.5 17.0 0.5
3
Bensulide
22 55.0 57.8 56.4 91.6 96.3 94.0 4.1 7.3
7.8 13.9 0.6
23 25.8 25.7 25.8 86.0 85.7 85.8 2.3 8.9 6.2 24.2 0.9
4
Butralin
21 18.3 18.2 18.2 91.3 91.2 91.3 1.4 7.4
2.3 12.8 0.4
22 8.5 8.5 8.5 84.9 84.6 84.7 0.5 6.2 2.2 26.2 0.8
5
Chlorpyrifos
19 185.2 183.7 185.3 92.6 91.8 92.2 9.6 5.2 18.7 10.1 0.5
22 83.5 86.9 84.3 83.5 86.9 85.2 5.7 6.8 25.0 29.7 1.3
6
Clomazone 23 18.9 18.7 18.9 94.7 93.3 94.0 1.3 6.7
2.1 11.2 0.4
22 8.9 9.0 8.9 88.6 90.4 89.5 0.3 3.8 2.0 22.7 0.7
7
Diazinon
22 19.4 19.0 19.2 96.9 95.0 96.0 0.9 4.9
2.6 13.4 0.5
20 9.2 9.2 9.2 92.3 92.2 92.2 0.3 3.6 1.3 13.6 0.4
8 Ethoprophos 23 19.0 18.7 18.9 95.1 93.6 94.3 1.2 6.5
2.5 13.2 0.5
22 8.7 8.8 8.7 86.8 87.8 87.3 0.5 5.5 1.9 21.5 0.7
9
Flutolanil
23 19.1 19.1 19.2 95.3 95.7 95.5 1.4 7.5
2.5 13.0 0.4
23 8.7 8.9 8.8 87.3 88.8 88.0 0.4 5.1 1.9 21.3 0.7
10 Imidacloprid 23 42.7 42.1 42.6 94.8 93.5 94.2 3.3 7.7
5.3 12.4 0.5
23 19.5 19.9 19.7 86.9 88.3 87.6 1.2 6.2 5.4 27.4 0.9
11 Indoxacarb
23 19.0 18.7 18.9 95.0 93.6 94.3 1.3 6.7
2.4 12.7 0.4
22 9.1 9.6 9.3 91.4 96.0 93.7 0.8 8.2 2.1 22.7 0.7
12 Kresoxim-methyl
20 200.5 189.6 191.8 100.2 94.8 97.5 15.9 8.3 25.1 13.1 0.6
22 81.6 88.0 83.7 81.6 88.0 84.8 8.5 10.2 18.9 22.5 1.0
13 Monolinuron 23 19.0 18.6 18.9 95.0 93.1 94.0 1.5 7.9
2.5 13.4 0.5
22 9.0 9.2 9.1 90.0 92.4 91.2 0.6 6.2 1.8 19.2 0.6
14 Picoxystrobin 21 19.4 18.8 19.0 97.2 94.0 95.6 1.3 6.8
2.3 12.1 0.4
23 8.9 9.0 8.9 88.5 89.6 89.1 0.8 8.9 2.1 24.1 0.7
15 Pirimiphos-
methyl
23 19.3 19.2 19.3 96.6 96.0 96.3 1.0 5.3
2.6 13.5 0.5
22 9.1 8.9 9.1 91.2 89.3 90.2 0.4 4.6 1.7 19.1 0.6
16
Propoxur
23 47.7 47.4 47.9 95.3 94.9 95.1 4.5 9.4
8.2 17.1 0.7
23 21.9 22.4 22.2 87.7 89.8 88.7 1.4 6.1 6.1 27.4 1.0
17 Quinoxyfen 22 92.9 92.1 92.7 92.9 92.1 92.5 4.7 5.0 12.8 13.8 0.6
23 41.1 41.4 41.2 82.2 82.8 82.5 2.5 6.0 9.5 23.1 0.9
18 Tebufenpyrad 23 18.7 18.8 18.8 93.6 94.1 93.8 1.1 6.0
2.5 13.5 0.5
23 8.9 8.9 8.9 89.2 89.0 89.1 0.6 6.4 2.4 26.8 0.8
19 Triadimefon 22 18.9 19.1 19.1 94.4 95.7 95.1 1.2 6.4
2.7 13.9 0.5
22 9.5 9.3 9.4 94.8 92.5 93.7 0.5 4.8 1.9 20.1 0.6
20 Trifloxystrobin 21 19.3 19.1 19.3 96.4 95.4 95.9 1.2 6.1
2.0 10.5 0.4
23 8.9 8.9 8.9 89.2 89.4 89.3 0.4 4.9 2.1 23.9 0.7