Evaluation of Generic PAH Profiles Commonly Used in Receptor Models: Implications for Source Control Policy

The use of receptor models, such as EPA’s Chemical Mass Balance, to develop source control policies requires careful consideration of the validity of model inputs. Given the challenges of determining appropriate site-specific polycyclic aromatic hydrocarbons (PAH) source profiles, researchers investigating sources of PAHs in sediments often take profiles from the literature. Some published profiles, such as those first proposed in Li et al. (2003), have been used so often they have effectively become default inputs. In this paper, we investigate the origins of Li’s profiles, and use statistical methods to evaluate how accurately they represent the sources claimed. The results indicate that due to high intrasource variability and intersource similarities, Li’s profiles fail to meet assumptions underlying receptor models and should not be used as generic PAH source inputs. Implications of the misapplication of receptor models used to promote source control policies are discussed. The results call into question a series of papers that claim that refined tar pavement sealers are a significant source of PAHs in urban sediments.