ISSN 0975-6299 Vol.1/Issue-4/Oct-Dec.2010 www.ijpbs.net Pathology B - 315 International Journal of Pharma and Bio Sciences ALTERATIONS IN THE PROFILE OF BLOOD CELLS OF WISTAR RATS INDUCED BY LONG-TERM INGESTION OF CHLORPYRIFOS SAROJNI TRIPATHI AND AJAI KUMAR SRIVASTAV* Department of Zoology, DDU Gorakhpur University, Gorakhpur 273 009, India *Corresponding Author ajaiksrivastav@hotmail.com ABSTRACT Male Wistar rats were divided into three groups -- A, B and C. Two groups (B and C) of animals were daily administered orally chlorpyrifos at a dose of 5 and 10 mg/kg b wt., respectively. One group (A) was employed as control. Rats were sacrificed 24 h after last dose on 1 st , 2 nd , 4 th , 6 th , and 8 th week after initiation of the experiment. Morphological alterations in blood cell profiles induced by chlorpyrifos treatment were investigated on hematological preparations made by routine methods. Results of the present study indicate that chlorpyrifos provoked an alteration of rat erythrocyte morphology from the normal discoid shape to other forms such as echinocytes, dacrocytes, schistocytes etc. Following chlorpyrifos treatment, few faded red blood cells were encountered. Many cells were degenerated thus at places cell debris were present. Few nucleated red cells were also seen. KEY WORDS Chlorpyrifos, Blood cells, Organophosphate, Rat INTRODUCTION Pesticides, a unique group of compounds, are used to prevent, control or eliminate pests which are a major cause of crop losses in the field as well as in storage. These pests have always been a nuisance and create multidimensional problems for human beings. The discovery of organic pesticides provided man with a new and powerful weapon for his incessant war against pests. Pesticides have benefited human beings by controlling insects, disease transmitting rodents, noxious arthropods and pests of plants including crops and forests. But pesticides may have dual actions – they are important in controlling injurious pests but they may also present a hazard to species not considered to be pests in the environment. This ill-effect becomes particularly significant when pesticides directly affect populations of economically important organisms or poison organisms which are eaten by economically important animals and human beings. The effects of toxicants may be lethal or sublethal. Lethal effects may result in death of the organism (mostly in acute effects). A typical lethal effect is failure of the chemically exposed organisms to produce viable offspring’s. The most common sublethal effects are behavioural changes (e.g. swimming, attraction avoidance