During World War II, 2,3-dimercaprol (BAL) was developed as a chelating agent by British biochemists at Oxford University. BAL has been used clinically for arsenic, cadmium and mercury poisoning since 1949. Chemically, BAL is a three carbon chain with two sulfhydryl (-SH) groups and a hydroxyl (-OH) group (Figure 4). It is an oily, colorless liquid with a pungent odor. It is used clinically for lewisite (an organoarsenic compound) poisoning and acts by forming a stable five-member ring complex with the arsenic moiety (Figure 4). BAL is most effective when administered immediately after exposure to lewisite. BAL is also an efficient antidote for mercury poisoning. However, the metals are rapidly mobilized within the body. As a result of this
