تأثيرات الكادميوم في السمية الحادة لمبيدات حشرية مثبطة لنشاط إنزيم الكولين إستيريز في الفئران

Abstract EN

The purpose of this study was to examine in male mice the acute toxicity of cadmium and representative organophosphate and carbamate cholinesterase inhibiting insecticides and their interaction at the levels of the 24 h median lethal dose (LD50), isobologram analysis and toxicity index.

The LD50 value of cadmium was 8.6 mg/kg of body weight, intraperitoneally.

Cadmium-treated mice showed writhing responses with difficulty in movement and walking.

The oral LD50 values the organophosphate insecticides dichlorvos, diazinon, cuomaphos, chlorpyrifos were 81.6, 157.6, 192.4 and 437.1 mg/kg of body weight, respectively; whereas those of the carbamate insecticides carbaryl and methomyl were 940.2 and 177.5 mg/kg of body weight, respectively.

Mice intoxicated with insecticides showed signs of salivation, lacrimation, piloerection, straub tail, flat body appearance, muscle fasciculation, tremor, convulsion, dyspnea followed by death within 24 of oral dosing.

When cadmium was injected 30 min before the insecticide dosing, the LD50 values of cadmium and those of the insecticides decreased (increased toxicity) by 51.4 to 74% and 48.3 to 86.8%, respectively, in comparison to their individual LD50 values in mice.

Isobologram analysis revealed that the toxic interaction between cadmium and the insecticides was synergistic.

The toxicity index also indicated that the interaction between cadmium and the insecticides was synergistic because its values were < 1.

These results suggest that administering cadmium with organophosphate and carbamate insecticides at acute toxic doses in mice causes acute synergistic toxic interaction as identified by the LD50 experiments, isobologram analysis and toxicity index.