Avoidance response as a sublethal effect of pesticides on Lumbricus terrestris (Oligochaeta)

Earthworms (Lumbricus terrestris) were exposed to ten pesticides with differing chemical structures, modes of action, and application rates to determine whether earthworm avoidance response occurs consistently and may be useful in evaluating effects of pesticides on earthworms. Earthworms were placed in the treated compartment of a two-compartment glass chamber and were allowed unrestricted movement between treated and untreated compartments. After 48 h, each chamber was x-rayed to determine the extent of movement, i.e. avoidance response. Earthworm avoidance occurred for all pesticides studied and increased as concentration increased.