L-Cysteinesulfinic acid monohydrate is primarily used in biochemical research to study the metabolism of sulfur-containing amino acids. It serves as a precursor in the synthesis of taurine, a compound important for cardiovascular and neurological functions. Additionally, it is utilized in investigating the role of sulfinic acids in cellular signaling pathways and oxidative stress responses. Its application extends to the development of pharmaceuticals targeting metabolic disorders and neurodegenerative diseases. In enzymology, it acts as a substrate for enzymes like cysteine dioxygenase, aiding in understanding enzyme mechanisms and kinetics.