Introduction There is a problem of regulation in petroleum products’ distribution in My Country- the mode of filling cars using funnel and hose, vandalization, black marketing, storing fuel privately. Deliberate inhalation of hydrocarbons as a form of recreational drug use, has become a significant health issue affecting children and adolescents (Azeez et al 2015). The large number of motor vehicles exhaust typically found in an urban disaster site can be a source of many hydrocarbon chemicals, including gasoline, many of these substances are a mixture of hydrocarbons (Lisa A. Murphy et al, 2003). The morbidity and mortality associated with Atrial fibrillation (AF) is substantial. AF is responsible for more hospitalizations and longer hospital stays than any other arrhythmia, and may also lead to stroke, congestive heart failure, myocardial infarction, and death; Many episodes of AF are asymptomatic or minimally symptomatic. Methodology: Procedures involving animals and their care were performed in accordance with the National Institutes of Health (NIH) guideline for the care and use of animals (NIH publication No 85-23, revised 1996). 25 Adult male Wister rats were grouped to 5 with 5 rats in a group. Group 1 control was given feed and water ad-libitum but not exposed to petrol fume. Groups 2, 3, 4, and 5 were exposed to petrol fume 10 minutes every day for eight weeks. Groups 3, 4 and 5 had candesartan (16mg/kg body weight), captopril (25 mg/kg body weight) and Moringa oleifera extract (40 mg/kg body weight)before exposure to petro fume. The petrol fume was generated by using human compressor nebulizer adopted for rats with the rats kept in fume chamber. At the end of the eight weeks, rats were aneasthezised with 1% chloralose and 25% urethane intraperitoneally; the electrocardiography was done using EDAN 10. Result: The ECG recording (ECG lead II) of group 2 (rats exposed to petrol only) showed no clearly detectable P-wave very narrow QRS complexes and very high heart rate. The ECG recording in group 3-Candesartan cilexcetil (an AT II receptor blocker) showed was comparable with the recording of Moringa oleifera group(5). Conclusion: The similarity in amelioration of Atrial fibrillation by Moringa oleifera and candesartan cilexetil on ECG recording suggests that the action of Moringa oleifera is likely to be an antagonist of Angiotensin II receptor. Key words: Moringa oleifera, candesartan cilexetil, Electrocardiography, Atrial fibrillation.