College of Engineering
BSE (Bachelor of Science in Engineering)
Session and Year of Graduation
Honors Major Advisor
Keri C. Hornbuckle, Rachel F. Marek
This project determined airborne concentrations of persistent, toxic polychlorinated biphenyls (PCBs) inside and outside homes in urban East Chicago, Indiana. Possible sources of PCBs to home air include modern pigments present in house paint and cabinet varnish, adhesives and sealants, and historical Aroclor mixtures of PCBs such as what is found in some old window caulking, insulation, and light ballasts. PCB concentrations in outdoor air of these homes may be impacted by the dredging of the Indiana Harbor and Ship Canal (IHSC). The IHSC is a PCB-contaminated waterway that is currently being dredged by the Army Corps of Engineers. Indoor and outdoor air samples were collected by field staff using polyurethane foam passive air samplers (PUF-PAS) before and after dredging started. We establish the following hypotheses for this study: That Aroclor and non-Aroclor PCBs and their possible sources can be identified inside East Chicago homes, and that the IHSC is a source of PCBs to home air.
Samples collected before dredging started (n=73) and after dredging started (n=62) were analyzed for all 209 PCBs. The 62 samples collected after dredging started are the focus of this thesis. Extraction efficiency, reproducibility, and accuracy were assessed using surrogate standards and replicates of method blanks. Using the cosine theta measure of similarity, prominent potential sources to indoor air were found to be the IHSC (21 samples with cos theta greater than 0.8) and Aroclor 1254 (9 samples with cos theta above 0.8). Two of the 32 samples did not have any close matches to Aroclors or IHSC air, and they were compared against top congeners in other known sources to home air. Some contributing sources from this analysis were cabinet varnish, yellow and green colorants, and adhesive. We expect the results of this study to inform our stakeholders, including our study participants, the East Chicago community, the Army Corps of Engineers, and the EPA, of the effect of this dredging and of common housing construction materials on airborne PCBs.
polychlorinated biphenyls, PCBs, indoor air, aroclors, indiana harbor and ship canal
Copyright © 2021 Maeve Bittle