A 34 year old lady, Ruchi, with a diagnosis of borderline personality disorder was admitted to the medicine casualty with claims of consumption of some form of poison following an argument with her husband. She was reluctant to disclose the nature of the consumed substance. She was initially treated with stomach wash and IV fluids. She developed jaundice followed by ascites and encephalopathy after 1 week. What is the likely poison that is responsible for acute liver failure?