Toxicity Assessment of Expired Pesticides to Green Algae
Pseudokirchneriella subcapitata
Table 3
Percent inhibition of yield (%) and growth rate (%) at 72 hours.
S. no.
Name of the pesticide
Conc. exposed (mg/L)
Percent inhibition
Percent inhibition
unexpired
expired
(%)
(%)
(%)
(%)
Insecticides
1
Dichlorvos 76% EC
0.95
1.57
0.30
−1.05
−0.20
3.05
11.52
2.31
3.66
0.71
9.77
32.46
7.42
21.99
4.70
31.25
45.03
11.30
30.37
6.84
100.00
99.48
86.82
91.10
45.02
2
Endosulfan 35% EC
0.10
2.09
0.40
1.68
0.32
0.31
21.99
4.70
11.17
2.27
0.98
57.59
16.18
33.52
7.81
3.13
84.82
35.31
67.04
21.16
10.00
100.00
100.00
92.18
47.85
3
Quinalphos 25% EC
0.10
8.38
1.68
2.23
0.43
0.31
16.76
3.51
12.29
2.51
0.98
41.34
10.20
34.64
8.13
3.13
73.74
25.45
69.83
22.83
10.00
97.21
65.50
94.97
55.66
Pyrethroids
4
Alphacypermethrin 10% SC
0.1
1.68
0.32
2.79
0.54
0.31
11.17
2.27
19.55
4.16
1.0
33.52
7.81
44.69
11.32
3.1
67.04
21.16
75.42
26.70
10.0
92.18
47.85
95.33
57.69
5
Fenvalerate 20% EC
0.1
0.56
0.11
5.59
1.10
0.31
4.47
0.88
19.55
4.16
1.0
22.35
4.84
47.49
12.31
3.1
44.69
11.32
77.09
28.02
10.0
81.01
31.54
96.09
59.96
6
Lambda-cyhalothrin 5% EC
0.1
1.55
0.29
4.12
0.79
0.31
11.34
2.27
15.46
3.17
1.0
100.00
100.00
100.00
100.00
3.1
100.00
100.00
100.00
100.00
10.0
100.52
100.00
100.52
100.00
Herbicides
7
Fenaxaprop-p-ethyl 9.3% EC
0.10
1.83
0.34
8.22
1.58
0.31
25.11
5.33
36.53
8.38
0.98
73.06
24.09
82.19
31.61
3.13
89.04
40.32
94.52
52.44
10.00
99.09
79.63
100.00
100.00
8
Pretilachlor 50% EC
0.10
−1.05
−0.20
6.28
1.23
0.31
14.14
2.88
21.99
4.70
0.98
46.60
11.85
50.79
13.38
3.13
84.82
35.31
92.67
48.49
10.00
97.91
69.39
100.00
100.00
9
2,4 D sodium salt 80% WP
0.10
1.06
0.20
5.29
1.03
0.31
7.94
1.57
16.93
3.51
0.98
21.16
4.51
35.98
8.44
3.13
47.62
12.23
62.43
18.49
10.00
99.47
86.79
100.53
100.00
Fungicides
10
Tebuconazole 25% EC
0.10
−2.23
−0.42
1.12
0.22
0.31
2.79
0.54
9.38
1.68
0.98
11.17
2.27
22.35
4.84
3.13
46.93
12.11
61.45
18.19
10.00
91.06
45.44
96.65
62.53
11
Mancozeb 75% WP
0.10
2.58
0.49
6.70
1.31
0.31
10.31
2.05
22.16
4.72
0.98
13.40
2.71
38.66
9.21
3.13
46.39
11.74
58.25
16.43
10.00
90.21
43.19
97.94
69.48
12
Hexaconazole 5% EC
0.10
5.29
1.03
13.23
2.69
0.31
15.34
3.16
18.52
3.88
0.98
51.85
13.82
58.20
16.49
3.13
66.14
20.44
73.02
24.70
10.00
97.35
65.85
100.00
100.00
Combinational fungicides
13
Captan 70% + Hexaconazole 5% WP
0.03
1.02
0.19
0.51
0.10
0.10
11.68
2.34
9.14
1.80
0.31
25.38
5.50
22.34
4.75
0.98
62.44
18.36
44.67
11.11
3.13
92.89
48.79
96.95
63.20
10.00
100.51
100.00
100.51
100.00
14
Carbendazim 12% + Mancozeb 63% WP
0.003
1.02
0.19
−2.03
−0.38
0.010
24.37
5.25
1.52
0.29
0.03
62.44
18.36
24.37
5.25
0.10
80.20
30.24
54.82
14.91
0.31
96.45
60.68
62.44
18.36
1.00
100.51
100.00
97.97
69.57
15
Metalaxyl 8% + Mancozeb 64% WP
0.002
1.15
0.22
−4.02
−0.76
0.005
25.86
5.76
1.72
0.33
0.02
60.34
17.74
20.11
4.32
0.05
71.84
24.26
54.60
15.16
0.16
86.21
37.68
86.21
37.68
0.50
99.43
86.58
98.28
73.16
Same concentrations were used for both unexpired and expired pesticide formulations exception for Metalaxyl 8% + Mancozeb 64% WP (expired). Concentrations of Metalaxyl 8% + Mancozeb 64% WP (expired) are 0.003, 0.010, 0.03, 0.10, 0.31, and 1.00 mg/L.
