Umwelt- und analytische Toxikologie

Artificial Soil Test of Phorate on Eisenia fetida

Abstract

Suneel Kumar and Singh SM

Phorate an organophosphate insecticide is commonly applied on crops to kill the stem borers but major part of it reaches on the soil which is a pivotal component of the environment. The soil possesses diverse and numerous life forms amongst which earthworms are considered as major representative organisms. The level of toxicity of various pesticides is found different and is considered as one of the valuable parameters in killing the agricultural pests. In the present paper the acute toxicity (LC50) of phorate was evaluated for the epigeic earthworm, Eisenia fetida and assessed by artificial soil test method as per proposed in OECD testing guideline No. 207 (1984). Results showed that acute toxicity (LC50) of phorate was found to be 22.5 mg/kgat the end of 14 day artificial soil test, and is considered as ‘extremely toxic’ to the experimental worm. The purpose of the study was to ascertain its minimal dose to be applied to kill the pests but not the earthworms. These findings showed that a dose of less than its acute toxicity level may be applied on the crops that will not affect the earthworms.