This class of chemicals is considered ubiquitous in the marine environment. The atmospheric origin of PAHs are by-products of the incomplete combustion of fossil fuels, wood, residential heating, and vehicular emissions. Many variations of PAHs are considered to be human carcinogens
(Delhomme, et al., 2008).
The same 11 roofs were sampled in November of 2013 and October of 2014. Methods of contaminant analysis for the 2013 and 2014 sampling differed slightly. The 2013 sampling looked at contaminants soluble in the runoff. The 2014 sampling looked at those, as well as all solid materials in the sample. We changed the method due to concern that compounds fixed to the sample's debris were not being accounted for.
|Runoff samples were collected during rain storms.|
|Although in small concentrations, nearly all PAH's tested for were present in roof runoff.|