This chapter, which examines the entire issue, will facilitate progress in addressing the problem to the marine environment and humanity. OMCs exhibit distinctive reactivity profiles, ligand exchange kinetics, and redox potentials, rendering them suitable for various applications. The reader will gain an awareness of the fundamental needs, developments, and difficulties encountered in the aquatic environment from this chapter and investigate the consequences of OMCs on the marine environment, although joint efforts and preventive measures are being made to mitigate their detrimental implications on the marine ecosystem. Discussions of conclusions, trends, and viewpoints are included.