Acute and Subacute Toxicity Studies of Cyperus Papyrus Ash on Wistar Albino Rats

Background: Acute and subacute toxicity screenings of medicinal plants are the fastest way to evaluate the toxicological profiles of medicinal plants. It helps to have a quick idea of the harm or safety potency of drugs. This study aims to conduct an acute and subacute oral toxicity study on the Cyperus Papyrus (CP) ash in Wistar albino rats. CP is traditionally used for managing painful spasms, eye diseases, ulcers, fever, diarrhea, and inflammations. Further study is required to reflect the safety profile of this plant ash. Methods: Acute oral toxicity study of the CP ash was evaluated by using a dose of 2000 mg/kg body weight on rats according to the Organization for Economic Co-operation and Development (OECD) guidelines using the Aot425 software. Subacute oral toxicity was carried out on 4 groups of 6 rats, at doses of 175 mg/kg, 550 mg/kg, 1750 mg/kg, and 1750 mg/kg. The recovery group (control group) received water according to OECD 407 guidelines for consecutive 28 days. At the end of the experiments (day 29), all rats were weighed and sacrificed except the rats of the recovery group which were continued without ash administration for extra 14 days and then weighed and sacrificed. Subsequently, the hematological parameters, plasma biochemical parameters, and histopathological examination were carried out. Results: Upon completion of the acute toxicity, no deaths or signs of acute oral toxicity were observed. Hematologic observations after oral subacute toxicity included a decrease in hematocrit percentage, mean corpuscular volume, and lymphocyte percentage, while there was a slight increase in the mean corpuscular hemoglobin concentration, however, it returned to the normal range in the recovery group. Biochemical tests showed a mild increase in the serum creatine and aspartate aminotransferase levels but they also returned to their normal range in the recovery group. No morphological changes in the kidney, liver, lung, spleen, heart or small intestine were observed after the histopathological examinations. Conclusion: Dried ash of CP is considered to be safe and non-toxic at acute exposure and as the lethal dose 50% value exceeds 2000 mg/kg body weight, it has a mild reversible effect on some hematological and biochemical parameters while no morphological changes of vital organ histopathology occur.