The enrichment theory has been widely adopted in estimating the NPS loading of nutrients and organic carbon (OC). Recent studies (zheng et al., 2012; Luo et al., 2013) revisited this theory, with a focus on PAHs. Luo et al. (2013) concluded that the tradi-tional theory interprets the enrichment phenomenon from an inappropriate perspective (i.e., particle size distribution instead of soil/sediment composition), and may not be valid for soils with significant amount of anthropogenic carbonaceous materials (CMs) like black carbon (BC). The anthropogenic CMs in soil, usually much larger than clay-size, strongly adsorb PAHs and play a dominant role in the enrichment of PAHs,. To appropriately estimate the NPS loading of PAHs from contaminated soils, the ER calculation needs to explicitly consider the transport process of influential CMs,which has not been attempted by existing models.