Nitrogen loading to coastal ecosystems is a growing concern. Elevated N can lead to hypoxic dead-zones, which in addition to negatively affecting the ecosystem, can lead to financial loss for shellfish aquaculturists. Significant sources of coastal eutrophication include both sewage effluent and agricultural fertilizer. Nitrogen isotope signatures (δ15N) serve as a valuable resource for detecting nitrogen pollution in a given environment and can indicate pollution source, as wastewater is typically enriched in 15N, while inorganic fertilizer is depleted in 15N. Marine mollusks are reliable recorders of environmental nitrogen isotope signatures, as they are typically primary consumers feeding on phytoplankton, which incorporate N from dissolved inorganic nitrogen. Mollusks are also locally common, have a global distribution, and generally withstand pollution. Mollusk tissues also integrate long time periods as opposed to point sampling water, providing time averaged δ15N values. In this project we aim to capitalize on the utility of several marine mollusk species to investigate pollution sources along the North Carolina coast in the Cape Lookout region. Specifically, we sampled the bivalve species Mercenaria mercenaria, Chione cancellata, Argopecten irradians, Noetia ponderosa, Donax variabilis, Crassostrea virginica and Atrina sp., and the gastropod species (welks) Busycon carica and Sinistrofulgur perversum during the summer of 2018. We sampled mollusks from regions of high and low housing density to examine the potential of elevated nitrogen pollution rates due to runoff from leach fields implemented in septic tank systems. We also sampled Mercenaria mercenaria tissues over time, with samples sporadically ranging back to 2012. Further, we measured shell length to assess a possible correlation between mollusk age and nitrogen isotope signature. Measured δ15N values indicated that areas characterized by dense housing are either unaffected by wastewater nitrogen loading or this phenomenon is counteracted by additional loading of nitrogen from fertilizer runoff with low δ15N values. At a given site, there is a large range in δ15N values within species, as well as between individuals of each species. Lack of overall shift in δ15N values between 2012 to 2018 suggests that there has been no significant change in N loading in this region throughout recent time.