Research Article

Toxicity of Metals to a Freshwater Snail, Melanoides tuberculata

Table 1

Median lethal times (LT50) for M. tuberculata exposed to different concentrations for Cu, Cd, Zn, Pb, Ni, Fe, Al, and Mn.

Nominal (and measured) concentration (mg L−1)LT50 (h)95% Confidence limits

Cu
 0.075 (0.081)
 0.1 (0.145)
 0.32 (0.292)
 0.56 (0.549)
 0.87 (0.915)
163.42
134.97
98.89
75.87
55.42
63.60–419.91
53.22–342.28
44.35–220.50
26.88–214.15
25.36–121.11

Cd
 0.56 (0.611)
 1.0 (1.21)
 5.6 (4.87)
 10 (10.82)
 32 (33.49)
283.44
114.89
57.21
22.34
7.82
85.46–940.12
52.78–250.09
30.29–108.05
11.03–45.27
4.63–13.23

Zn
 1.0 (1.09)
 5.6 (5.30)
 10 (8.19)
 32 (32.45)
 56 (49.60)
216.96
96.71
61.83
32.44
12.34
630.53–1541.63
52.82–177.09
39.85–95.94
22.13–47.55
8.25–18.45

Pb
 1.0 (1.02)
 5.6 (5.42)
 10 (10.95)
 18 (17.16)
 32 (31.18)
250.72
179.32
88.25
40.36
11.17
430.55–2057.69
38.42–837.02
30.24–257.71
13.91–117.15
6.71–18.57

Ni
 5.6 (5.51)
 10 (9.02)
 32 (31.53)
 75 (67.11)
 100 (97.84)
105.96
92.38
58.11
36.84
16.26
59.28–189.40
48.25–176.87
39.82–84.80
21.66–62.67
12.50–21.17

Fe
 5.6 (5.27)
 8.7 (8.86)
 10 (11.76)
 32 (33.47)
 56 (58.17)
134.97
102.06
79.72
34.71
20.04
53.22–342.28
40.17–259.29
28.18–225.53
13.36–90.15
7.5–53.51

Al
 56 (88.38)
 100 (160.83)
 320 (362.83)
 560 (884.34)
 1000 (1229.91)
80.87
57.91
42.75
18.57
8.40
111.48–58.66
87.09–38.50
65.99–27.70
40.94–8.42
18.52–3.81

Mn
 10 (12.98)
 32 (31.60)
 56 (57.81)
 87 (85.61)
 100 (97.01)
119.53
67.81
35.07
16.97
8.35
62.44–228.82
35.06–131.15
19.04–64.60
9.00–32.00
5.05–13.79