Cytotoxicity of short-term exposure to sublethal dose of the insecticide thiamethoxam to male albino rats

Thiamethoxam (TMX) is a systemic insecticide used to combat plant pests that might significantly affect food security. Therefore, the current study aimed to evaluate its mammalian toxicity against male albino rats following short-term administration of sublethal doses.

Two groups, control and treatment rats (eight males each), were orally administered distilled water and 1/20 LD50 (78.0 mg/kg B.W.) doses of TMX daily for 14 days. The biochemical, hematological, genotoxic, and histopathological responses were subsequently described.

The results revealed significant decreases in the specific activities of acetylcholinesterase (AChE), butyrylcholinesterase (BuChE), and Mg+-ATPase in the TMX-treated rats compared to those in the control group. Additionally, alterations in blood parameters were reported for treated individuals. Significant increases in the number of tailings (14%), tail length (3.43 µm), tail DNA (3.62%), and tail moment (12.56%) as well as the frequency of micronucleated erythrocytes (MNs) were found in the TMX-treated animals. Moreover, transmission electron microscopy (TEM) of blood samples revealed swollen mitochondria with light-dense cristae, vacuoles (V), nuclei (N) (contained migrated chromatin), and rough endoplasmic reticulum (RER) in comparison to the firm structure of the negative control.

TMX exposure, especially at low doses, is an alarming sign of possible health hazards.