Specifically Crude Oil (CAS #8002-05-9) contains Benzene, Butane, N-Hexane, Isopentane, Pentane, and Stoddard Solvent. Benzene is a known human carcinogen and is identified by NTP, OSHA, and IARC as a Group 1 carcinogen. Chronic inhalation of minute levels of benzene causes leukemia and other types of cancers.
Acute contact, via inhalation and skin, with small amounts of light crude oil and dispersants cause transitory respiratory, vomiting, diarrhea, and skin reactions. However, long-term exposure, which can be a matter of days or weeks, can cause central nervous system problems, or do damage to blood and organs such as kidneys or livers, according to the Centers for Disease Control and Prevention. There is also a significant increase in the risk of cancer.
Crude oil is not readily biodegradable and the effects of exposure to this toxin will be felt from generation to generation.