Inkyu Han

Dr. Inkyu Han


Research Focus & Metrics

Academic Career Length

12Years (2015-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2015 in Science of The Total Environment
Verified
Journal Article
Closed access
Aisha DickersonAisha Dickerson
Aisha Dickerson
MRMohammad H. Rahbar
Mohammad H. Rahbar
IHInkyu Han
Inkyu Han
ABAmanda V. Bakian
Amanda V. Bakian
DBDeborah A. Bilder
Deborah A. Bilder
JBJon Baio
Jon Baio

14 June 2016 in Environmental Monitoring and Assessment
Verified
Journal Article
Closed access
PDF file
Aisha DickersonAisha Dickerson
Aisha Dickerson
MRMohammad H. Rahbar
Mohammad H. Rahbar
ABAmanda V. Bakian
Amanda V. Bakian
DBDeborah A. Bilder
Deborah A. Bilder
RHRebecca A. Harrington
Rebecca A. Harrington
WZWalter M. Zahorodny
Walter M. Zahorodny

30 September 2016 in Journal of the Air & Waste Management Association
Verified
Journal Article
Closed access
IHInkyu Han
Inkyu Han
ESElaine Symanski
Elaine Symanski
TSThomas H. Stock
Thomas H. Stock
Exposure to ambient particulate matter (PM) is known as a significant risk factor for mortality and morbidity due to cardiorespiratory causes. Owing to increased interest in assessing personal and community exposures to PM, we evaluated the feasibility of employing a low-cost portable direct-reading instrument for measurement of ambient air PM exposure. A Dylos DC 1700 PM sensor was collocated with a Grimm 11-R in an urban residential area of Houston Texas. The 1-min averages of particle number concentrations for sizes between 0.5 and 2.5 µm (small size) and sizes larger than 2.5 µm (large size) from a DC 1700 were compared with the 1-min averages of PM2.5 (aerodynamic size less than 2.5 µm) and coarse PM (aerodynamic size between 2.5 and 10 µm) concentrations from a Grimm 11-R. We used a linear regression equation to convert DC 1700 number concentrations to mass concentrations, utilizing measurements from the Grimm 11-R. The estimated average DC 1700 PM2.5 concentration (13.2 ± 13.7 µg/m3) was similar to the average measured Grimm 11-R PM2.5 concentration (11.3 ± 15.1 µg/m3). The overall correlation (r2) for PM2.5 between the DC 1700 and Grimm 11-R was 0.778. The estimated average coarse PM concentration from the DC 1700 (5.6 ± 12.1 µg/m3) was also similar to that measured with the Grimm 11-R (4.8 ± 16.5 µg/m3) with an r2 of 0.481. The effects of relative humidity and particle size on the association between the DC 1700 and the Grimm 11-R results were also examined. The calculated PM mass concentrations from the DC 1700 were close to those measured with the Grimm 11-R when relative humidity was less than 60% for both PM2.5 and coarse PM. Particle size distribution was more important for the association of coarse PM between the DC 1700 and Grimm 11-R than it was for PM2.5. Implications: The performance of a low-cost particulate matter (PM) sensor was evaluated in an urban residential area. Both PM2.5 and coarse PM (PM10-2.5) mass concentrations were estimated using a DC1700 PM sensor. The calculated PM mass concentrations from the number concentrations of DC 1700 were close to those measured with the Grimm 11-R when relative humidity was less than 60% for both PM2.5 and coarse PM. Particle size distribution was more important for the association of coarse PM between the DC 1700 and Grimm 11-R than it was for PM2.5.

18 December 2021 in Environmental Pollution
Verified
Journal Article
Open access
IHInkyu Han
Inkyu Han
Kristina Walker WhitworthKristina Walker Whitworth
Kristina Walker Whitworth
BCBrian Christensen
Brian Christensen
MAMasoud Afshar
Masoud Afshar
HHHeyreoun an han
Heyreoun an han
ESElaine Symanski
Elaine Symanski
In August 2017, after Hurricane Harvey made landfall, almost 52 inches of rain fell during a three-day period along the Gulf Coast Region of Texas, including Harris County, where Houston is located. Harris County was heavily impacted with over 177,000 homes and buildings (approximately 12 percent of all buildings in the county) experiencing flooding. The objective of this study was to measure 13 heavy metals in soil in residential areas and to assess cancer and non-cancer risk for children and adults after floodwaters receded. Between September and November 2017, we collected 174 surface soil samples in 10 communities, which were classified as “High Environmental Impact” or “Low Environmental Impact” communities, based on a composite metric of six environmental parameters. A second campaign was conducted between May 2019 and July 2019 when additional 204 soil samples were collected. Concentrations of metals at both sampling campaigns were higher in High Environmental Impact communities than in Low Environmental Impact communities and there was little change in metal levels between the two sampling periods. The Pollution Indices of lead (Pb), zinc, copper, nickel, and manganese in High Environmental Impact communities were significantly higher than those in Low Environmental Impact communities. Further, cancer risk estimates in three communities for arsenic through soil ingestion were greater than 1 in 1,000,000. Although average soil Pb was lower than the benchmark of the United States Environmental Protection Agency, the hazard indices for non-cancer outcomes in three communities, mostly attributed to Pb, were greater than 1. Health risk estimates for children living in these communities were greater than those for adults.

5 April 2020 in Environmental Health
Verified
Journal Article
Open access
PDF file
ESElaine Symanski
Elaine Symanski
HHHeyreoun an han
Heyreoun an han
LHLoren Hopkins
Loren Hopkins
MSMary Ann Smith
Mary Ann Smith
SMSheryl McCurdy
Sheryl McCurdy
JFJuan Flores
Juan Flores
Background: From 2006 to 2011, the City of Houston received nearly 200 community complaints about air pollution coming from some metal recycling facilities. The investigation by the Houston Health Department (HHD) found that while operating within legal limits, emissions from facilities that use torch cutting, a technique generating metal aerosols, may increase health risks for neighboring residents. Choosing to use collaborative problem solving over legislative rulemaking, HHD reached out to The University of Texas Health Science Center at Houston (UTHealth) to further evaluate and develop plans to mitigate, if necessary, health risks associated with metal emissions from these facilities. Methods: Utilizing a community-based participatory research approach, we constituted a research team from academia, HHD and an air quality advocacy group and a Community Advisory Board (CAB) to draw diverse stakeholders (i.e., frustrated and concerned residents and wary facility managers acting within their legal rights) into an equitable, trusting and respectful space to work together. Next, we investigated metal air pollution and inhalation health risks of adults living near metal recyclers and ascertained community views about environmental health using key informant interviews, focus groups and surveys. Finally, working collaboratively with the CAB, we developed neighborhood-specific public health action plans to address research findings. Results: After overcoming challenges, the CAB evolved into an effective partnership with greater trust, goodwill, representation and power among members. Working together to translate and share health risk assessment results increased accessibility of the information. These results, coupled to community survey findings, set the groundwork for developing and implementing a stakeholder-informed action plan, which included a voluntary framework to reduce metal emissions in the scrap yard, improved lines of communication and environmental health leadership training. Tangible outcomes of enhanced capacity of our community and governmental partners included trained residents to conduct door-to-door surveys, adaptation of our field training protocol and survey by our community partner and development of a successful HHD program to engage residents to improve environmental health in their neighborhood. Conclusions: Academic-government-community-industry partnerships can reduce environmental health disparities in underserved neighborhoods near industrial facilities.

HHHeyreoun an han
Heyreoun an han
IHInkyu Han
Inkyu Han
SMSheryl McCurdy
Sheryl McCurdy
Kristina Walker WhitworthKristina Walker Whitworth
Kristina Walker Whitworth
GDGeorge Delclos
George Delclos
ESElaine Symanski
Elaine Symanski
On Sunday, 17 March 2019, a fire erupted at the Intercontinental Terminals Company (ITC, Deer Park, La Porte, TX, USA), resulting in a large fire that blazed for several days. In response, we rapidly launched disaster response activities to monitor air pollutants (total volatile organic compounds (TVOCs), fine particulate matter (PM2.5), black carbon (BC), and ultra-fine particles (UFPs) during the fire in two affected communities. To assess immediate health effects and residential air quality, we also rapidly launched a pilot study, the Deer Park Chemical Fire (DeeP Fire) Study, in which we administered health surveys and installed samplers to monitor air quality outdoors of resident homes for up to six weeks. In both communities, mean ambient concentrations of PM2.5, BC and TVOCs were higher during the first week of the fire than a week after it was extinguished. Thirteen residents participated in the DeeP Fire Study. Most residents reported experiencing respiratory symptoms and some reported being bothered by at least one post-traumatic stress disorder symptom during the fire and two weeks afterwards. In the months following the fire, the 7-day mean ambient concentration of benzene from 12 homes was 0.13 ± 0.10 parts per billion (ppb) and the 6-week mean ambient concentrations of PM2.5 and TVOCs were 13 ± 6 µg/m3 and 108 ± 98 ppb, respectively. All residents requested and received individualized air monitoring reports. Surveillance systems that enable real-time monitoring of the environmental health impact during a major industrial incident are needed to provide timely information to adequately respond to a disaster in the future.