EPA Designation Regulated
EPA Classification Organic Chemicals
EPA Levels 1,2 zero MCLG (mg/L)
0.0002 MCLG (mg/L)
Alternative Names PAHs
Sources Leaching from linings of water storage tanks and distribution lines
Benzo(a)pyrene is a polycyclic aromatic hydrocarbon that contaminates drinking water from leaching coal tar coatings on water distribution pipes and storage liners; it is also a product of combustion.


Benzo(a)pyrene is one of a group of compounds called polycyclic aromatic hydrocarbons.


They are not produced or used commercially but are very commonly found since they are formed as a result of incomplete combustion of organic materials.

Health Effects

Some people who drink water containing benzo(a)pyrene well in excess of the maximum contaminant level (MCL) for many years may experience reproductive difficulties and may have an increased risk of cancer.

EPA Data Source: Benzo(a)pyrene

EPA Definitions:

1Maximum Contaminant Level Goal (MCLG) - The level of a contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety and are non-enforceable public health goals.

Maximum Contaminant Level (MCL) - The highest level of a contaminant that is allowed in drinking water. MCLs are set as close to MCLGs as feasible using the best available treatment technology and taking cost into consideration. MCLs are enforceable standards.

Maximum Residual Disinfectant Level Goal (MRDLG) - The level of a drinking water disinfectant below which there is no known or expected risk to health. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contaminants.

(TT) Treatment Technique - A required process intended to reduce the level of a contaminant in drinking water.

Maximum Residual Disinfectant Level (MRDL) - The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants.

2 Units are in milligrams per liter (mg/L) unless otherwise noted. Milligrams per liter are equivalent to parts per million.