[{"from": "human", "value": "Could you give me a brief overview of this molecule? [As]"}, {"from": "gpt", "value": "The molecule is a nonessential trace element that is widely distributed in nature. Arsenic was used in medicinal agents in the 19th and early 20th centuries, but has been replaced by safer and more effective agents and has not been in use for over 50 years. Nevertheless, arsenic is found widely in nature and accidental or intentional acute or chronic exposures to moderate or high levels of arsenic can cause liver injury, sometimes presenting long after the exposure."}]