Abstract
Southwest Ohio has been known for PM2.5 issues due to emissions from multiple local sources, such as industry and multimodal traffic, as well as regional impacts from sulfates, nitrates, and ammonia. To better understand the speciation characteristics of PM2.5 in this area, data from five monitoring sites, Taft, Hook Field, St. Bernard, Lower Price Hill, and Chase, were studied for the time period of 2003 to 2013. The total concentration of PM2.5 has decreased significantly since the last decade, from 13.41 µg m–3 in 2003 to 10.55 µg m–3 in 2013. The overall PM2.5 concentration also exhibited seasonal variations, with four out of five of the highest concentrations occurring in summer and the fifth one occurring in winter. Due to various air pollution control measures (such as the Cross-State Air Pollution Rule, and Mercury and Air Toxics Standards), both the total concentrations and the speciation of PM2.5 have changed over time. The most dominant components of PM2.5 include sulfates, organic matter (OM), and nitrates, which contributed 33.4%, 31.7%, and 17.7%, respectively (Taft data from 2009 to 2013). Elemental carbon (EC) and crustal materials, on the other hand, accounted for much smaller portions—2.84% and 3.61%, respectively. The highest concentrations of sulfate occurred in summer, while those for nitrates occurred in winter. EC and OM followed the same seasonal trends, peaking in fall and summer and dropping to their lowest levels in winter. Crustal materials exhibited the lowest concentrations in winter. A comparison of Cincinnati (the Taft site) with other major cities nearby reveals that the highest concentration of PM2.5 and the largest fraction of sulfates is found in Cincinnati. Efforts to control these emissions are still necessary.
Highlights
It has been well demonstrated that airborne fine particulate matter (PM2.5), which refers to particulate matter of aerodynamic diameter less than 2.5 μm, is a significant contributor to visibility reduction (Islam et al, 2007; Sena et al, 2013)
The average PM2.5 concentration at Lower Price Hill is the highest among all five sites, with much higher organic matter (OM) fractions (48% vs. 39% at Taft) and slightly higher sulfate fractions (46% vs. 42% at Taft) as well as slightly higher Elemental carbon (EC) fractions than the Taft site
PM2.5 compositions in southwest Ohio were analyzed using data from the Chemical Speciation Network of US EPA, especially the data from the Taft site located in Cincinnati, OH
Summary
It has been well demonstrated that airborne fine particulate matter (PM2.5), which refers to particulate matter of aerodynamic diameter less than 2.5 μm, is a significant contributor to visibility reduction (Islam et al, 2007; Sena et al, 2013). As part of the American heartland, there have been less reports on the long-term PM2.5 speciation trends of the southwest Ohio area. Cincinnati is the largest metropolitan area in southwest Ohio on the Ohio River, Xie et al, Aerosol and Air Quality Research, x: 1–10, xxxx and is a hub of intermodal transport. It is the 14th largest port in the US (Army Corps of Engineers, 2015) and the 4th largest in the US in total rail mileage and highest in density of rail lines (ORDC, 2014). It has been known as a diesel hotspot due to high diesel traffic, and there has been a multiple year study, the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS), which found the increase correlation of children who lived near diesel traffic with asthma rate (Cheng et al, 2014)
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
