[ECG picture in rats exposed to the action of petroleum]

The male rats of Wistar strain were exposed to the vapours of arabic petroleum Abu-Dhaki Zakun at concentration 1500 mg/m(3) during 16 weeks, 6 times weekly per 90 minutes daily. The ECG examinations revealed progressive bradycardia, increase of the percentage of conduction disturbances appearing as the bundle-right branch block, changes of the shape of P deflection, decrease of the angle of inclination of QRS vector, and increase of the percentage of nonspecific changes of ST-T syndrome. The obtained results can suggest a noxious effect of petroleum on the heart muscle when given by inhalation in a determined concentration.