Oil is an important source of energy worldwide. However, oil is not found at every corner of the world, and hence the need to transport it across oceans by ships and across lands by pipelines. This results in accidents of oil vessels, leakage from pipelines. It is estimated that one ton of oil is spilled for every million tons of oil transported.
Drilling for oil causes small quantities of oil spills which spread to form deadly oil slicks. As oil has a lower density as compared to water, oil floats on top of water and is washed ashore.
Industrial waste produced in the process is also harmful to our health.
Read more in effects of oil pollution.