| Hazardous Chemicals | Adverse Health Effects |
| Benzene (crude oils high in BTEX, benzene, toluene, ethylbenzene, and xylene) | Irritation to eyes, skin, and respiratory system; dizziness; rapid heart rate; headaches; tremors; confusion; unconsciousness; anemia; cancer |
| Benzo(a)pyrene (a polycyclic aromatic hydrocarbon reproductive [see below], formed when oil or gasoline burns) | Irritation to eyes and skin, cancer, possible effects |
| Carbon dioxide (inerting atmosphere, byproduct of combustion) | Dizziness, headaches, elevated blood pressure, rapid heart rate, loss of consciousness asphyxiation, coma |
| Carbon monoxide (byproduct of combustion) Irritation to eyes, skin, and respiratory | Dizziness, confusion, headaches, nausea, weakness, loss of consciousness, asphyxiation, coma |
| Ethyl benzene (high in gasoline) | Irritation to eyes, skin, and respiratory system; loss of consciousness; asphyxiation; nervous system effects |
| Hydrogen sulfide (oils high in sulfur, decaying plants and animals) | Irritation to eyes, skin, and respiratory system; dizziness; drowsiness; cough; headaches; nervous system effects |
| Methyl tert-butyl ether (MTBE) (octane booster and clean air additive for gasoline, or pure MTBE) | Irritation to eyes, skin, and respiratory system; headaches; nausea; dizziness; confusion; fatigue; weakness; nervous system, liver, and kidney |
| Polycyclic aromatic hydrocarbons (PAHs) (occur in crude oil, and formed during burning of oil) | Irritation to eyes and skin, cancer, possible reproductive effects, immune system effects |
| Sulfuric acid (byproduct of combustion of sour petroleum product) | Irritation to eyes, skin, teeth, and upper respiratory system; severe tissue burns; cancer |
| Toluene (high BTEX crude oils) | Irritation to eyes, skin, respiratory system; fatigue; confusion; dizziness; headaches; memory loss; nausea; nervous system, liver, and kidney effects |
| Xylenes (high BTEX crude oils) | Irritation to eyes, skin, respiratory system; dizziness; confusion; change in sense of balance; nervous system gastrointestinal system, liver, kidney, and blood effects |