Characterization of Metals in Communities Surrounding Louisiana’s Chemical Corridor During HAP-MAP 2023
AMIRA YASSINE, Mina Tehrani, Edward Fortner, Shivang Agarwal, Ellis Robinson, Benjamin Werden, Benjamin A. Nault, Conner Daube, Megan Claflin, Andrea Chiger, Carolyn Gigot, Manjula Canagaratna, Scott Herndon, Tara Yacovitch, Thomas Burke, Kirsten Koehler, Keeve Nachman, Ana Rule, Peter F. DeCarlo, Johns Hopkins University
Abstract Number: 560
Working Group: Aerosol Exposure
Abstract
Inhalation of particulate-bound metals emitted from industrial facilities can pose human health risks. Louisiana’s chemical corridor is an 85-mile stretch along the Mississippi River and is one of the most industrialized areas of the US. While it is recognized that facilities here emit metals in aerosol particles, limited quantitative measurements of these pollutants exist. To date, only modeled metals concentrations are available, and these are typically reliant on the facilities' self-reported emissions data. Use of these data may lead to mischaracterization of the true burden of metals exposure; improved spatiotemporal measurements of metals are needed.
During a 4-week sampling campaign in February 2023, size-resolved PM filter measurements were done using a micro-orifice uniform deposit impactor (MOUDI) at a fixed site adjacent to a heavily industrialized waterfront in Louisiana’s chemical corridor. The collected filters were later analyzed offline using inductively coupled plasma mass spectrometry (ICP-MS) to determine the concentration of 19 PM bound metals.
ICP-MS measurements showed that the toxic trace metals manganese, arsenic, antimony, and lead concentrations in total PM were higher than EPA-modeled estimates by 85 %,77%, 55%, and 43% respectively. The highest concentrations of lead, vanadium, antimony, and arsenic were within the 0.20 and 0.34 µm PM fractions (which can penetrate deeply into the lungs) (mean concentrations 0.51, 0.44, 0.26, and 0.18 ng/m3 respectively).
Source apportionment analysis suggested six major metal sources: sea salt, mineral dust, non-exhaust vehicles, and three distinct industrial-related sources (zinc-dominated industrial emissions, industrial activities, and industrial combustion). Toxic trace metals lead, antimony, arsenic, and vanadium were mostly attributed to the industrial combustion factor (their percentages were 99%, 97%, 96%, and 90% correspondingly).
These findings suggest that communities surrounding Louisiana’s chemical corridor might be exposed to industrial-related atmospheric metals and metalloids that surpass estimates derived from EPA modeling tools.