Acute exposure and histopathological effects of drilling fluid in rats

IntroductionThis study aimed to assess the acute toxic properties of drilling fluid (DF), a multicomponent substance extensively utilized in oil extraction, through a single intragastric administration in mature male rats, to better understand its potential health risks.MethodsAcute toxicity was evaluated in mature male rats via a single intragastric administration of DF at doses of 300, 600, 1200, 2400, and 4800 mg/kg. Mortality, body weight changes, and relative organ weights were monitored throughout the study. Biochemical enzyme activities, including ALT, AST, ALP, and LDH, were assessed. Behavioral responses were recorded, and histological examinations of the liver, kidneys, and heart were conducted to evaluate tissue-level effects.ResultsAdministration of DF caused significant toxic effects including mortality (2 deaths at 2400 mg/kg; 3 deaths at 4800 mg/kg), changes in body weight, and relative weights of liver (control: 7.12 ± 0.53; 2400 mg/kg: 7.89 ± 0.51; 4800 mg/kg: 9.68 ± 0.67; p < 0.001) and heart (control: 1.24 ± 0.17; 2400 mg/kg: 0.97 ± 0.21; 4800 mg/kg: 0.84 ± 0.08; p < 0.001). Activities of cytolytic enzymes ALT (control: 78.65 ± 4.28; 4800 mg/kg: 89.47 ± 2.62; p < 0.001) and AST (control: 226.18 ± 31.66; 4800 mg/kg: 322.73 ± 8.02; p < 0.001), as well as ALP and LDH, were significantly altered. Behavioral activity was markedly reduced. Histological changes were observed in the liver, kidneys, and heart tissues.DiscussionThese findings demonstrate that DF exhibits marked acute toxicity and causes significant physiological and histopathological damage in mammals, indicating a potential hazard.