Effect of Chlorpyrifos on the Hematology and Phagocytic Activity of Nile Tilapia Cells (Oreochromis niloticus)

Abstract

Chlorpyrifos is an organophosphorous insecticide widely used in agriculture and domestic activities. However, little is known about the effect of this pesticide on the immune system of fish and other alterations of its physiological system. The aims of the present study were the evaluation of the LC(50) (lethal concentration(50)) and the potential toxicity of this substance on Nile tilapia (Oreochromis nilotucus), as well as its effect on some hematological values and phagocytic functions of this fish. Results obtained showed that chlorpyrifos does not have any effect on the following parameters: number of red blood cells, hemoglobin, hematocrit, mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). However, the phagocytic index and the percentage of phagocytic active cells were significantly affected, which could indicate that phagocytic parameters from Nile tilapia are more sensitive than hematological ones to assess the effect of acute intoxication with chlorpyrifos.

Haematological parameters as bioindicators of insecticide exposure in teleosts

“…However, subadults of common carp C. carpio exposed to low concentrations of trichlorofon had no marked effect on Hct value (Chandrasekara and Pathiratne 2005). Likewise, Giron-Perez et al (2006) noticed a non-significant alteration in TEC, Hb content and Hct in Nile Tilapia (Oreochromis niloticus) acutely exposed to 0.422, 0.845, 1.69 and 3.38 ppm of chlorpyrifos. In another study, the same fish suffered from erythropenia, marked decline in Hb and Hct values after long-term post exposure to dimethoate and malathion (Sweilum 2006; Table 1).…”

“…Acute and chronic exposure to sublethal concentrations of phosphomidon to H. fossilis caused marked rise in MCH, MCHC and MCV values. Giron-Perez et al (2006) noticed alterations in the values of MCV, MCH and MCHC in O. niloticus treated with 3.38 ppm of chlorpyrifos. Adedeji et al (2009) also recorded a significant decline in MCV and MCH values in C. gariepinus exposed to diazinon.…”

“…Leucocytes Giron-Perez et al (2006) studied phagocytic index (average number of yeast engulfed per cell and calculated by dividing the total number of yeast engulfed by the cell count) and a percentage of phagocytic active cells (neutrophils and monocytes) along with several other haematological parameters in O. niloticus exposed to sublethal concentrations of an OP insecticide chlorpyrifos. They noted a marked decline in phagocytic index and percentage of phagocytic active cells concomitant with non-significant alterations in haematological indices and suggested that phagocytic parameters are more sensitive than haematological ones in assessing the toxicity of the insecticides.…”

Effect of Sub-lethal Concentrations of Endosulfan on Phagocytic and Hematological Parameters in Nile Tilapia (Oreochromis niloticus)

“…Therefore, this parameter could be used to evaluate exposure to pesticides that may alter the health of tilapia, as shown previously using the organophosphate pesticide chlorpyrifos (Girón-Pérez et al 2006). Taking this into account, fish cultured in areas close to agricultural activities could be affected by commercial formulations of pesticides, either by the active ingredients or the ''inert'' components (Cox and Surgan 2006).…”

Immunotoxicological Effects of Environmental Contaminants in Teleost Fish Reared for Aquaculture

“…Chlorpyrifos displayed little immunotoxicity, although there was a dose-dependent reduction in Murray cod lymphocytes (Harford et al, 2005). Nile tilapia exposed to the LC50 failed to change blood parameters but the phagocytic activity was significantly reduced (Girón-Pérez et al, 2006). Chlorpyrifos exposure produced an up-regulation of hsp60, hsp70 and hsp90 genes, related to the cellular stress response in Chinook salmon.…”