Foraging activity
After the set-up of the bumblebee colonies in the tunnels on -3DAA4 the bumblebees started to forage immediately with 0.8 to 2.8 entering and leaving bumblebees/10 min (Table 2). In all 4 treatment groups, the control C, the chlorantraniliprole groups T1 and T2 and the toxic reference R, flight activity increased until the day of application A4 with 8.0 to 12.0 bumblebees/10 min. No statistically significant differences were observed in T1, T2 and R before application A4 compared to the control. Directly after the application (0DAA4) no statistically significant differences were seen between C and T1 with 11.3 and 9.7 entering and exiting bumblebees/10 min, but flight activity was observed to be slightly but significantly lower in T2 with 6.5 bumblebees/10 min (p ≤ 0.05, Dunnetts t-test). However, from 1DAA4 until 16DAA4 no statistically significant differences were observed between the control and the chlorantraniliprole groups T1 and T2, except for a significantly higher flight activity in T1 on 5DAA4 (p ≤ 0.05, Dunnetts t-test). The mean flight activity in C, T1 and T2 was not statistically significant different during the whole exposure period with 10.9, 12.5 and 11.9 bumblebees/10 min, respectively. Instead, the flight activity in the toxic reference R was significantly reduced on all assessment dates from 0DAA4 until 16DAA4 (p ≤ 0.05, pooled t-test, Satterthwaite t-test, Mann Whitney exact test).
Table 2
Mean bumblebee flight activity (Mean number of forager bees entering and leaving the hive per 10 min) in chlorantraniliprole treatment group T1 and T2, control (C) and toxic reference (R)
Date
|
DAA4
|
Flight activity
(Mean number of forager bees entering and leaving the hive per 10 min)
|
C
|
T1
|
T2
|
R
|
14 Jun 2019
|
-3
|
2.0
|
2.8
|
0.8
|
1.3
|
15 Jun 2019
|
-2
|
3.5
|
4.3
|
4.5
|
5.3
|
16 Jun 2019
|
-1
|
8.0
|
12.0
|
11.3
|
10.0
|
17 Jun 2019
|
0
|
11.3
|
9.7
|
6.5* a)
|
2.0* b)
|
18 Jun 2019
|
1
|
12.0
|
8.3
|
8.2
|
0.0* c)
|
19 Jun 2019
|
2
|
12.0
|
11.0
|
12.0
|
0.0* c)
|
20 Jun 2019
|
3
|
9.0
|
8.2
|
7.8
|
0.0* c)
|
21 Jun 2019
|
4
|
5.7
|
9.2
|
4.7
|
0.0* c)
|
22 Jun 2019
|
5
|
5.3
|
10.7* a)
|
9.7
|
0.0* d)
|
23 Jun 2019
|
6
|
15.7
|
14.2
|
21.8
|
0.0* c)
|
24 Jun 2019
|
7
|
9.7
|
10.8
|
11.7
|
0.0* c)
|
26 Jun 2019
|
9
|
6.0
|
10.7
|
7.7
|
0.0* c)
|
29 Jun 2019
|
12
|
12.5
|
17.5
|
21.7
|
0.0* c)
|
01 Jul 2019
|
14
|
21.8
|
26.2
|
26.7
|
0.0* c)
|
03 Jul 2019
|
16
|
29.3
|
31.7
|
24.0
|
0.0* c)
|
Mean of tunnel phase
|
10.9
|
12.5
|
11.9
|
1.2* b)
|
DAA4 = days after 4th application; Mean = mean value of all tunnel replicates; STD = standard deviation of the mean of the tunnel replicates; |
* statistically significant difference compared to control (p ≤ 0.05) |
a) Dunnetts t-test; b) pooled t-test; c) Satterthwaite t-test; d) Mann Whitney exact |
Adult and larval mortality
During the initial exposure phase from − 3DAA4 to -1DAA4 the adult and larval mortality determined inside the hive was low and not statistically significant different in the control, the chlorantraniliprole groups T1 and T2 and the toxic reference R with maximally 0.3 dead workers/day and 0.3 larvae/day (Table 3). Adult and larval mortality observed in the hives was generally low and not statistically significant different in T1 and T2 compared to the control during the study from − 3DAA4 to 25DAA4, with maximum values of 1.7 dead workers per day in C on 18DAA4, 1.1 in T1 on 25DAA4 and 1.8 in T2 on 1DAA4. There were no statistically significant differences in mean total mortality during the exposure phase found in C, T1 and T2 with 2.5, 2.2 and 4.3 dead adult workers and 4.2, 5.8 and 4.5 dead larvae inside the colonies, respectively. In the toxic reference mortality of adult bumblebees was statistically significant higher compared to the control on all assessment days from 0DAA4 to 14DAA4 (p ≤ 0.05, Satterthwaite t-test, Mann Whitney exact test), except for 5DAA4 and 6DAA4, with a maximum number of 22.7 dead workers on 1DAA4. The mean total mortality of workers during the exposure period was also statistically significantly higher with 94.3 dead workers in the toxic reference compared to 2.5 workers in the control (p ≤ 0.05, Mann Whitney exact test).
Table 3
Mean number of dead in-hive bumblebee adults and larvae in chlorantraniliprole treatment group T1 and T2, control (C) and toxic reference (R)
Date
|
DAA4
|
Mean number of dead in-hive bumblebee adults and larvae
|
C
|
T1
|
T2
|
R
|
Adults
|
Larvae
|
Adults
|
Larvae
|
Adults
|
Larvae
|
Adults
|
Larvae
|
14 Jun 2019
|
-3
|
0.2
|
0.0
|
0.0
|
0.2
|
0.0
|
0.0
|
0.3
|
0.3
|
15 Jun 2019
|
-2
|
0.2
|
0.2
|
0.0
|
0.2
|
0.0
|
0.0
|
0.0
|
0.3
|
16 Jun 2019
|
-1
|
0.3
|
0.3
|
0.0
|
0.0
|
0.0
|
0.0
|
0.0
|
0.0
|
17 Jun 2019
|
0
|
0.0
|
0.3
|
0.0
|
0.5
|
0.0
|
0.0
|
9.0* b)
|
0.0
|
18 Jun 2019
|
1
|
0.0
|
0.5
|
0.2
|
1.3
|
1.8
|
0.2
|
22.7* b)
|
3.7* b)
|
19 Jun 2019
|
2
|
0.0
|
0.3
|
0.2
|
0.2
|
0.3
|
0.0
|
18.7* b)
|
3.7
|
20 Jun 2019
|
3
|
0.0
|
0.2
|
0.2
|
0.0
|
1.0
|
1.2
|
13.7* b)
|
2.0
|
21 Jun 2019
|
4
|
0.0
|
0.2
|
0.0
|
0.0
|
0.0
|
0.5
|
5.3* b)
|
6.3
|
22 Jun 2019
|
5
|
0.3
|
0.7
|
0.2
|
0.3
|
0.2
|
0.0
|
3.3
|
2.0
|
23 Jun 2019
|
6
|
0.2
|
0.5
|
0.0
|
0.2
|
0.0
|
0.2
|
0.7
|
11.0* b)
|
24 Jun 2019
|
7
|
0.0
|
0.2
|
0.0
|
0.3
|
0.0
|
0.2
|
2.7* b)
|
0.0
|
26 Jun 2019
|
9
|
0.0
|
0.0
|
0.1
|
0.0
|
0.1
|
0.0
|
1.8* b)
|
0.2
|
29 Jun 2019
|
12
|
0.1
|
0.1
|
0.1
|
0.2
|
0.0
|
0.1
|
1.7* b)
|
0.0
|
01 Jul 2019
|
14
|
0.3
|
0.1
|
0.1
|
0.1
|
0.1
|
0.3
|
3.2* a)
|
0.2
|
03 Jul 2019
|
16
|
0.3
|
0.2
|
0.4
|
0.9
|
0.3
|
0.8
|
1.5
|
0.0
|
Sum of tunnel phase1)
|
2.5
|
4.2
|
2.2
|
5.8
|
4.3
|
4.5
|
94.3* b)
|
30.0
|
05 Jul 20192)
|
18
|
1.7
|
1.2
|
0.4
|
2.8
|
0.6
|
3.0
|
-
|
-
|
09 Jul 2019
|
22
|
0.3
|
1.3
|
0.3
|
1.8
|
0.4
|
3.1
|
-
|
-
|
12 Jul 2019
|
25
|
0.6
|
9.7
|
1.1
|
6.4
|
1.1
|
11.8
|
-
|
-
|
DAA4 = days after 4th application; Mean = mean value of all tunnel replicates; STD = standard deviation of the tunnel replicates; - = no data available (all hives deep-frozen) |
Mean mortality is only shown for days, on which values for all replicates were available (between 29 and 36 DAA4 individual replicates were deep-frozen). |
1) Calculated as mean of the total sum of dead bumblebee adults or larvae from − 3 to 16 DAA4 |
2) First assessment on monitoring site |
* statistically significant difference compared to control (p ≤ 0.05) |
a) Satterthwaite t-test; b) Mann Whitney exact |
Only very few dead adult and larval bumblebees were found additionally in the tunnels on the linen sheets. The sum of dead bumblebee adults and larvae found in the tunnels C, T1, T2, and R during the whole exposure phase was 0.3, 0.5, 0.2 and 3.0 bees, respectively. Only the R treatment was statistically significant different to the control (p ≤ 0.05, Mann Whitney exact).
Colony weights
The mean bumblebee colony weights were not statistically significant different between the control and the T1 and T2 throughout the study (-3DAA4 to 25DAA4) (Table 4). Colony weights increased continuously from 1DAA4 until 25DAA4 with maximum weights of 487 g, 617 g and 596 g in the control and T1 and T2, respectively. The total weight increase from − 3DAA4 until deep-freezing of the colonies was also similar and not statistically significant different with 396 g in the control, 524 g in T1 and 488 g in T2. Colony weights in the toxic reference were similar to the control from − 3DAA4 until 1DAA4 and decreased from 2DAA4 onwards. The mean total colony weight increase from − 3DAA4 until 16DAA4 was statistically significantly lower in the toxic reference R compared to the control (p ≤ 0.05, Satterthwaite t-test).
Table 4
Mean weight of bumblebee colonies (g ± standard deviation (STD)) in chlorantraniliprole treatment group T1 and T2, control (C) and toxic reference (R)
Date
|
DAA4
|
Mean weight of bumblebee colonies
(g ± standard deviation)
|
C
|
T1
|
T2
|
R
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
14 Jun 2019
|
-3
|
96
|
7
|
101
|
13
|
108
|
11
|
101
|
20
|
15 Jun 2019
|
-2
|
88
|
5
|
93
|
11
|
99
|
9
|
93
|
17
|
16 Jun 2019
|
-1
|
88
|
6
|
97
|
13
|
102
|
8
|
92
|
14
|
17 Jun 2019
|
0
|
90
|
7
|
106
|
14
|
110
|
10
|
92
|
12
|
18 Jun 2019
|
1
|
101
|
9
|
115
|
12
|
110
|
9
|
85
|
17
|
19 Jun 2019
|
2
|
113
|
8
|
123
|
13
|
113
|
10
|
79* a)
|
16
|
20 Jun 2019
|
3
|
124
|
7
|
142
|
16
|
132
|
13
|
75* a)
|
17
|
21 Jun 2019
|
4
|
141
|
8
|
161
|
18
|
149
|
16
|
71* a)
|
14
|
22 Jun 2019
|
5
|
155
|
9
|
179
|
23
|
164
|
20
|
70* a)
|
13
|
23 Jun 2019
|
6
|
157
|
10
|
183
|
21
|
164
|
16
|
70* a)
|
11
|
24 Jun 2019
|
7
|
178
|
12
|
206
|
29
|
190
|
15
|
67* a)
|
10
|
26 Jun 2019
|
9
|
209
|
11
|
254
|
50
|
238
|
25
|
51* a)
|
18
|
29 Jun 2019
|
12
|
270
|
21
|
355
|
69
|
336
|
40
|
61* a)
|
8
|
01 Jul 2019
|
14
|
338
|
33
|
444
|
79
|
440
|
47
|
60* a)
|
6
|
03 Jul 2019
|
16
|
391
|
65
|
493
|
76
|
491
|
50
|
56* b)
|
7
|
05 Jul 20191)
|
18
|
399
|
63
|
502
|
90
|
498
|
55
|
-
|
-
|
09 Jul 2019
|
22
|
468
|
88
|
587
|
106
|
568
|
73
|
-
|
-
|
12 Jul 2019
|
25
|
487
|
80
|
617
|
105
|
596
|
73
|
-
|
-
|
Total weight increase [g] 2)
|
396
|
79
|
524
|
89
|
488
|
65
|
1* b)
|
2
|
DAA4 = days after 4th application; Mean = mean value of all tunnel replicates; STD = standard deviation of the tunnel replicates; - = no assessment performed or not calculable |
1) first assessment on monitoring site |
2) Total weight increase per colony calculated by subtracting the first assessment date from the maximum weight measured (calculated separately for each replicate from set-up (-3 DAA4) until deep-freezing of the colony). |
Mean weights are only shown for days, on which values for all replicates were available (between 29 and 36 DAA4 individual replicates were deep-frozen). |
* statistically significant difference to control (p ≤ 0.05) |
a) pooled t-test; b) Satterthwaite t-test |
Colony development
At the initial brood assessment, before the bumblebee colonies were set up in the tunnels, all bumblebee colonies were queen-right and in good condition with a mean number of 57.3 workers per colony in C, 57.3 in T1, 57.2 in T2 and 56.0 in R. Additionally, all colonies showed similar strength with regard to the number of living brood stages and food storage. No statistically significant differences in the condition of the bumblebee colonies of T1, T2 and R compared to the control were observed at the initial brood assessment (Table 5). Also, at the final brood assessment no statistically significant differences in the number of the individual living or dead brood stages were found in T1 and T2 compared to the control. The total number of living adult and living brood stages were similar in the control, T1 and T2 with 99.2 living adult bees and 263.3 living brood stages in C, 153.3 and 431.8 in T1 and 135.0 and 453.5 in T2, respectively. In the toxic reference the following parameters were statistically different from the control: the number of living workers, the number of living young and old larvae (separately and the sum) and the number of dead larvae (p ≤ 0.05, pooled t-test, Satterthwaite t-test). Also, the total number of living adult and living brood stages was significantly reduced compared to the control with 12.0 living adult bees and 63.0 living brood stages in R compared to 99.2 living adult bees and 263.3 living brood stages in C (p ≤ 0.05, pooled t-test, Satterthwaite t-test). Foundress queen mortality was observed in one of six replicates of T2 during the exposure phase (2DAA4). The reason for the death of the foundress queen was not clear and the colony appeared to be healthy. The cause of this unexplained mortality was assumed to be natural background mortality and not treatment related. It is not unusual, that one foundress queen is lost during a study. Therefore, the foundress queen was replaced with a foundress queen from a similarly treated hive. Apart from this replicate no foundress queen mortality was observed in any of the control or chlorantraniliprole T1 and T2 colonies. In the toxic reference all foundress queens died within the first 5 days after the application.
Table 5
Summary of results of initial and final colony assessments for chlorantraniliprole treatment group T1 and T2 control (C) and toxic reference (R)
Number of adult and larval stages (Mean ± standard deviation) and Colony weight (g ± standard deviation)
|
Initial colony assessment: 13 Jun 2019
|
Life stage
|
C
|
T1
|
T2
|
R
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
Living queens
|
1
|
0
|
1
|
0
|
1
|
0
|
1
|
0
|
Living workers
|
57.3
|
7.0
|
57.3
|
7.6
|
57.2
|
9.6
|
56.0
|
7.2
|
Brood cells with eggs
|
7.0
|
2.1
|
7.8
|
2.7
|
8.7
|
2.3
|
8.0
|
1.0
|
Brood cells with young larvae (package)
|
64.3
|
16.0
|
68.2
|
14.4
|
52.7
|
12.2
|
68.7
|
36.0
|
Brood cells with old larvae (isolated)
|
16.8
|
10.5
|
24.7
|
11.5
|
28.8
|
6.4
|
24.7
|
5.9
|
Living pupae (worker/males)
|
49.0
|
8.7
|
50.2
|
13.9
|
47.5
|
13.3
|
42.3
|
14.5
|
Filled nectar cells
|
30.3
|
9.2
|
25.2
|
4.3
|
27.7
|
3.6
|
31.7
|
15.5
|
Colony weight [g]
|
86.5
|
8.4
|
87.3
|
14.3
|
96.8
|
13.9
|
88.0
|
18.5
|
Total living brood stages
(eggs, larvae, pupae)
|
137.2
|
15.8
|
150.8
|
30.0
|
137.7
|
20.8
|
143.7
|
51.3
|
Total living stages
(brood and adult bees)
|
194.5
|
15.4
|
208.2
|
28.9
|
194.8
|
27.0
|
199.7
|
57.7
|
Final colony assessment: 08–15 Aug 2019
|
Life stage
|
C
|
T1
|
T2
|
R
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
Living workers
|
34.7
|
18.4
|
45.5
|
10.7
|
41.7
|
10.6
|
11.7* a)
|
10.3
|
Dead workers
|
4.8
|
4.2
|
11.2
|
8.8
|
8.7
|
5.2
|
1.3
|
1.5
|
Eggs
|
33.2
|
25.7
|
82.7
|
81.7
|
125.5
|
41.6
|
15.3
|
5.9
|
Living young larvae
|
74.3
|
39.4
|
114.5
|
52.3
|
124.8
|
71.0
|
0.0* b)
|
0.0
|
Living old larvae (isolated, worker/males)
|
21.5
|
11.7
|
33.7
|
16.8
|
21.0
|
3.0
|
3.0* a)
|
3.0
|
Sum of living larvae (worker/males)
|
95.8
|
48.8
|
148.2
|
60.6
|
145.8
|
69.8
|
3.0* b)
|
3.0
|
Sum of dead larvae (worker/males)
|
24.0
|
16.6
|
22.8
|
10.2
|
14.7
|
11.8
|
138.0* a)
|
46.6
|
Living pupae (worker/males)
|
45.0
|
13.1
|
101.7
|
56.2
|
61.0
|
50.6
|
44.7
|
8.1
|
Dead pupae (worker/males)
|
3.5
|
3.3
|
5.7
|
5.1
|
10.7
|
8.0
|
1.3
|
1.2
|
Filled nectar cells
|
1.5
|
1.8
|
4.2
|
5.5
|
13.8
|
7.7
|
0.7
|
0.6
|
Filled pollen cells
|
2.8
|
1.9
|
3.8
|
2.2
|
4.5
|
3.0
|
7.0
|
5.3
|
Colony weight [g]
|
382.8
|
67.0
|
533.3
|
93.9
|
496.7
|
61.8
|
56.0* b)
|
6.2
|
Total living brood stages (eggs, larvae, pupae)
|
263.3
|
92.5
|
431.8
|
154.6
|
453.5
|
142.6
|
63.0* b)
|
12.1
|
Total living adult bees (young queens, worker bees, males)
|
99.2
|
14.0
|
153.3
|
52.9
|
135.0
|
17.5
|
12.0* a)
|
9.8
|
Total living stages
(brood and adult bees)
|
362.5
|
101.9
|
585.2
|
176.0
|
588.5
|
141.3
|
75.0* a)
|
21.5
|
STD = standard deviation; - = not available |
Calculation of weights based on unrounded values |
* statistically significant difference compared to control (p ≤ 0.05) |
a) pooled t-test; b) Satterthwaite t-test; c) Mann Whitney exact |
Drone and queen production
The mean number of emerged young queens and males produced in the control (56.0), T1 (96.3) and T2 (83.7) did not show any statistical differences. Also, no statistical differences in the numbers of living queen brood were observed for T1 with 0.7 queen larvae and 98.7 queen pupae, T2 with 3.5 queen larvae and 117.7 queen pupae compared to 3.8 queen larvae and 85.5 queen pupae in the control. Accordingly, the total number of living queen stages was also similar with 145.3 in C, 195.7 in T1 and 204.8 in T2. The mean queen weight (weighed individually) was not significantly different with 0.89 g in T1 and 0.90 g in T2 compared to 0.87 g in the control (Table 6). The mean number of emerged young males produced in the control (8.5), T1 (11.5) and T2 (9.7) did also not show any statistically significant differences. The numbers of dead queen and male stages were all very low and similar across C, T1 and T2.
Table 6
Mean number of young queens and males (n ± standard deviation (STD)) and mean queen weight (n ± standard deviation (STD)) in chlorantraniliprole treatment group T1 and T2, control (C) and toxic reference (R)
Life stage
|
Mean number of young queens and males (adults and brood stages) (n ± standard deviation) and Mean queen weight (g ± standard deviation)
|
C
|
T1
|
T2
|
R
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
Mean
|
STD
|
Living males
|
8.5
|
10.2
|
11.5
|
6.7
|
9.7
|
18.4
|
0.3
|
0.6
|
Dead males
|
0.0
|
0.0
|
0.5
|
0.5
|
0.2
|
0.4
|
0.0
|
0.0
|
Living queen larvae
|
3.8
|
3.4
|
0.7
|
1.0
|
3.5
|
4.1
|
0.0* a)
|
0.0
|
Dead queen larvae
|
0.2
|
0.4
|
0.3
|
0.5
|
0.3
|
0.5
|
0.0
|
0.0
|
Living queen pupae
|
85.5
|
17.6
|
98.7
|
50.5
|
117.7
|
44.8
|
0.0* a)
|
0.0
|
Dead queen pupae
|
16.2
|
37.7
|
4.7
|
4.8
|
9.7
|
7.7
|
0.0
|
0.0
|
Emerged young queens
|
56.0
|
19.3
|
96.3
|
38.5
|
83.7
|
15.2
|
0.0* a)
|
0.0
|
Dead young queens
|
0.0
|
0.0
|
0.3
|
0.5
|
0.2
|
0.4
|
0.0
|
0.0
|
Mean queen weight [g]
|
0.87
|
0.08
|
0.89
|
0.04
|
0.90
|
0.02
|
-
|
-
|
Living queen stages
(young queens, larvae, pupae)
|
145.3
|
29.2
|
195.7
|
55.7
|
204.8
|
53.1
|
0.0* b)
|
0.0
|
STD = standard deviation; - = not available |
Calculation of weights based on unrounded values |
* statistically significant difference compared to control (p ≤ 0.05) |
a) Satterthwaite t-test; b) Mann Whitney exact |
Residues
In the 20 cm topsoil that was initially sprayed at 265.15 g chlorantraniliprole/ha, 75% of the target rate was found assuming a standard soil bulk density of 1.5 g/cm³ (Table 1). The analytical dose verification of the different Chlorantraniliprole 20SC spray solutions resulted in 93 to 108% recovery of the target rates (Table 1).
No chlorantraniliprole residues above the LOQ of 0.0005 mg/kg were detected in any control samples in pollen and nectar collected from forager bees and from samples taken inside the colonies that were taken in parallel to the samples in T1 and T2. The results of the residue analysis for T1 and T2 are given in Table 7. The chlorantraniliprole residues determined in pollen taken at 1DBA4 were similar in T1 and T2 with residue levels ranging between 0.1350 and 0.3660 mg/kg. In T1 the pollen residue levels showed a clear decreasing trend and at the last sampling date (29DAA4) the pollen residue levels with 0.0013 mg/kg were only slightly above the LOQ. Following the spray application (A4) during P. tanacetifolia flowering in T2 the pollen residues increased to 29.7 and 6.75 mg/kg in forager bee pollen and in pollen sampled from wax pots inside the colonies, respectively. During the next 2 to 3 days the residue levels determined in forager bee pollen and in pollen sampled from wax pots inside the colonies decreased rapidly to roughly 10 to 100-fold lower residue levels. During the following days the pollen residue levels decreased further and at the last sampling date (29DAA4) an in-hive pollen residue level 0.0032 mg/kg was measured. The chlorantraniliprole residue levels determined in nectar were generally much lower than those found in pollen. At the first nectar sampling on 1DBA4 similar residue levels of 0.0030 and 0023 mg/kg were found in T1 and T2. In T1 the nectar residue levels showed a clear decreasing trend and on the last day of exposure in the tunnels (16DAA4) the nectar residue levels with 0.0008 mg/kg were only slightly above the LOQ. After the spray application (A4) during P. tanacetifolia flowering in T2 the nectar residues increased to 0.140 and 0.143 mg/kg in forager bee nectar and in nectar sampled from wax pots inside the hives, respectively. During the following days the residue levels determined in both nectar matrices decreased rapidly and at the last sampling date (29DAA4) the in-hive nectar residue level was below LOQ.
Table 7
Residue concentrations of chlorantraniliprole (mg/kg) detected in pollen and nectar from forager bees (Forager) or collected from wax pots inside the hives (Hive) in chlorantraniliprole treatment group T1 and T2, control (C) and toxic reference (R)
|
Pollen (mg chlorantraniliprole/kg)
|
Nectar (mg chlorantraniliprole/kg)
|
|
T1
|
T2
|
T1
|
T2
|
|
Forager
|
Hive
|
Forager
|
Hive
|
Forager
|
Hive
|
Forager
|
Hive
|
1DBA4
|
0.1720
|
0.3440*
|
0.1350
|
0.3660
|
<LOQ*
|
0.0030
|
0.0023
|
-
|
0DAA4
|
0.1900
|
0.3340
|
29.7000
|
6.7500
|
0.0031
|
0.0032
|
0.1400
|
0.1430
|
1DAA4
|
0.2110
|
0.2320
|
3.8000
|
2.3800
|
0.0029
|
0.0021
|
0.0099
|
0.0075
|
2DAA4
|
0.0735
|
0.1020
|
0.4660
|
0.3520
|
0.0021
|
0.0027
|
0.0112
|
0.0113
|
3DAA4
|
0.0557
|
0.0433
|
0.2100
|
0.5440
|
0.0020
|
0.0026
|
0.0037
|
0.0043
|
4DAA4
|
0.0255
|
0.0412
|
0.1180
|
0.2240
|
0.0022
|
<LOQ
|
0.0039
|
0.0067
|
5DAA4
|
0.0614
|
0.2580
|
-
|
0.0116
|
0.0017
|
<LOQ
|
0.0066
|
0.0079
|
6DAA4
|
0.0247
|
0.0192
|
0.1210
|
0.1660
|
0.0008
|
0.0009
|
0.0030
|
0.0050
|
7DAA4
|
0.0112
|
0.0156
|
0.0855
|
0.1310
|
0.0012
|
0.0014
|
0.0027
|
0.0041
|
10DAA4
|
0.0117
|
0.0071
|
0.0268
|
0.0181
|
0.0010
|
<LOQ
|
0.0022
|
0.0048
|
14DAA4
|
0.0335
|
0.0262
|
0.0135
|
0.0092
|
0.0015
|
n.d.
|
0.0015
|
0.0015
|
16DAA4
|
0.0369
|
0.0191
|
0.0185
|
0.0275
|
0.0008
|
0.0008
|
0.0013
|
0.0021
|
22DAA4
|
-
|
0.0039
|
-
|
0.1110
|
-
|
-
|
-
|
0.0010
|
29DAA4
|
-
|
0.0013
|
-
|
0.0032
|
-
|
-
|
-
|
<LOQ
|
* Sample taken 2DBA4 |
n. d. = not detectable |
- = the collected amount was not sufficient for the analytical procedure/no samples of forager bees taken after 16 DAA4 |
LOQ (Limit of quantification): 0.0005 mg chlorantraniliprole/kg |