Table 1.

Lethal concentrations (LC_1–99) of chlorpyrifos for earthworm, Eudrilus eugeniae (identified by well-defined clitellum, n = 10).

Lethal	Chlorpyrifos	95% Confidence limits
Concentration	(μg/cm2)	Lower	Upper
LC1	0.095	0.033	0.123
LC5	0.112	0.051	0.137
LC10	0.122	0.064	0.145
LC15	0.129	0.074	0.151
LC50	0.165	0.134	0.186
LC85	0.211	0.187	0.296
LC90	0.223	0.196	0.342
LC95	0.243	0.209	0.425
LC99	0.286	0.233	0.646
Slope ± SEM	9.74 ± 3.10
Intercept ± SEM	12.62 ± 2.37
Χ2 value	3.02
P	<0.05

Control group (theoretical spontaneous response rate) = 0.000.