Internal combustion engines (ICEs), though primarily designed for mechanical power generation, can play an indirect yet significant role in addressing major environmental challenges such as oil spills and plastic pollution. While ICEs are themselves sources of emissions and fossil fuel consumption, their adaptability and widespread use make them essential for powering cleanup operations and supporting emerging sustainable technologies. In oil spill remediation, ICEs provide the propulsion and mechanical energy required for skimmer vessels, vacuum recovery boats, and containment deployment systems that collect and control spilled oil on water surfaces. Onshore, ICE-powered pumps and vacuum units assist in removing contaminated sand and water, facilitating oil separation and recovery. Similarly, in combating marine plastic pollution, ICE-driven boats and collection systems are used to retrieve floating debris, while ICE-powered vehicles transport collected plastics to recycling or processing facilities. Advances in waste-to-energy and plastic-to-fuel technologies further highlight a circular potential, where recovered plastics are converted into alternative fuels that can power ICEs, reducing overall waste and fossil fuel dependence. Additionally, the integration of biofuels and hybrid ICE systems can minimize carbon emissions during environmental operations. Although ICEs are not direct solutions to pollution, their mechanical versatility and evolving fuel technologies position them as valuable tools in transitional efforts toward cleaner, more sustainable methods of oil spill and plastic waste management.