Toxic Tuesdays

Total petroleum hydrocarbons (TPH) are a family of hundreds of chemicals that come from crude oil. When crude oil is spilled during extraction or processing into petroleum products, TPHs can contaminate the environment. Because TPHs contain so many chemicals, it can be impractical or impossible to measure each individual chemical. Instead, total concentrations of TPHs are measured at contamination sites. Upon contaminating soil, some TPH components will remain there for a long time without breaking down. Upon contaminating water, some components will form films on the surface while others will sink to the bottom. Touching contaminated soil or drinking contaminated water can lead to exposure to TPHs. Because many products and gasolines are derived from crude oil, almost everyone has some exposure to TPHs even in the absence of a chemical spill. For instance, breathing the air at gas stations or using certain pesticides can cause exposure to TPHs.

Exposure to TPHs can have effects on the nervous system, causing headaches, dizziness, or numbness in the extremities. Some TPH chemicals can also affect the blood, immune system, respiratory system, and skin. In laboratory studies on animals, TPH exposure was also found to affect liver function, kidney function, and fetal development. Furthermore, at least one TPH chemical – benzene – is known to cause cancer in humans. Despite known health effects of exposure to TPHs, and the potential for synergistic effects of simultaneous exposure to multiple TPH chemicals, there are no federal regulations specific to TPHs.

CHEJ has previously written about the health effects of some chemicals commonly found in TPH and communities that have been exposed to them: benzene, naphthalene, toluene, and xylene.