Assessment of Morphological and Histological Damages in Earthworms (Aporrectodea caliginosa) Exposed to Organophosphate Insecticide

Document Type : Original Article


1 Zoology and Entomology Departments, Faculty of Science, Assiut University, 71516 Assiut, Egypt,

2 Department of Biomedical Science, College of Medicine, King Faisal University, Alhasa, Saudi Arabia. -Department of Histology, Faculty of Medicine, Assiut University, Assiut, Egypt


Earthworms have great environmental importance; they occupy a great place among other soil invertebrates. Further, it contributes greatly to soil fertility and is a main component of the soil fauna. Various chemical pesticides are used that have multiple effects on plants in the soil ecosystem. Earthworms represent a strong bioindicator for the environmental toxicity analysis of soil pollution caused by pesticides. Chlorpyrifos is used in more than 100 countries and is applied annually to approximately more than a million acres of crops. The most beneficial crops include cotton, almonds, corn, fruit trees, oranges, bananas, and apples. In the present work, it was noticed that groups exposed to chlorpyrifos, an organophosphate pesticide, at doses of 0.05, 0.1, and 0.2 μg /cm² when compared with normal earthworms, it significantly affects the behavior of the worms, as it causes many distortions in the external appearance and also affects the stages of the earthworm life cycle, which lead to cocoon, juvenile, and adult death. When examining the histological sections, much damage to the tissues was observed. Even the pesticide led to much mortality among earthworms.