External impacts of fossil fuels on the environment include, but are not limited to, oil spills, air pollution, water pollution, plastic pollution. On the issue of air pollution, fossil fuels produce extremely dangerous air pollutants such as sulfur dioxide, nitrogen oxides, particulate matter, carbon monoxide, and mercury, all of which are harmful to the environment and the overall human health. Air pollution from fossil fuels can cause eutrophication, meaning, excessive nutrients that can harm aquatic ecosystems by lowering oxygen levels. 

It can also damage crops and forests, and harm to wildlife. Air pollution from fossil fuels can cause acid rain too. Fossil fuel extraction, transportation, and refining can lead to oil spills that have the potential to harm communities and wildlife, destroy habitats, erode shorelines, and result in beach, park, and fishery closures. From oil spills to fracking fluids, fossil fuels cause water pollution. Fracking well uses a lot of water, and the resulting wastewater can be very poisonous. It often contains substances like arsenic, lead, chlorine, and mercury that can contaminate groundwater and drinking water. 

 Much of plastics are made from fossil fuels. These plastics end up in the ocean, killing wildlife and polluting the food chain. Plastics also have climate consequences: the U.S. plastic industry produces 232 million tons(Beyond Pastics, 2021) of carbon dioxide equivalent per year, and the industry’s greenhouse gas emissions are expected to surpass those of coal-fired power plants by 2030.