The biggest polluters of oil drilling companies are accidental oil spills and workers illegally dumping oil barrels and produced water. "Produced water" is water produced by drilling oil, and it contains arsenic, cadmium, lead, mercury, copper and zinc. This water is toxic to both humans and animals.
People can suffer many different symptoms as well as long term health issues from exposure to these polluters, including skin rashes, headaches, digestive problems, lung disease, liver damage, brain damage and miscarriages. The heavy metals, such as lead, arsenic and mercury, are extremely toxic to humans and animals, even in very small proportions. For example, mercury is not excreted very quickly and builds up in tissue much faster causing toxic levels. One other polluter of oil drilling is corrosion of the piping used to extract the oil, as this can also contaminate the land and water surrounding the piping. There are also dust particles left over from drilling that coats the surrounding areas.
Whole ecosystems, such as rain forests, can be destroyed by oil drilling. Some of the best reserves of oil in the world are found in rain forests. Oil drilling causes polluters to be spilled into rivers, creeks and streams, causing damage to the ecosystem.