CHEEC Seed Grants: FY 2006

Demonstration Project for Source-Receptor Modeling of Vehicular Toxic Gases and Particles 
C. Stanier, Department of Chemical and Biochemical Engineering, University of Iowa

Mouse Model of Experimental Asthma Using (1->3)-->-B-D- Glucan Derivatives 
N. Metwali, P. Thorne, Department of Occupational and Environmental Health, University of Iowa

Development of a Single Particle Analysis Technique for Real-Time Monitoring and Characterization of Bioaerosols 
M. Young, Department of Chemistry, University of Iowa

Polychlorinated Biphenyls are an "Old" Issue: Telomere Toxicity Accelerates Senescence and Promotes Carcinogenesis 
J. Jacobus, Interdisciplinary Degree in Toxicology, G. Ludewig, Department of Occupational and Environmental Health, A. Klingelhutz, Department of Microbiology, University of Iowa

The Prevalence and Control of Fragrance Compounds in Iowa Drinking Water 
K. Hornbuckle, W. Wombacher, Department of Civil and Environmental Engineering, University of Iowa 

 


Demonstration Project for Source-Receptor Modeling of Vehicular Toxic Gases and Particles 
Investigator: C. Stanier, Department of Chemical and Biochemical Engineering, University of Iowa 
This proposal describes the development of a personal exposure screening tool for prediction of gas- and aerosol-phase vehicular air toxics. The tool will marry existing approaches for gaseous pollutants together with emerging techniques and data for size-resolved fine, ultrafine, and nanoscale particulate matter (mainly from diesel exhaust). Including size-resolved particulate matter in a screening model is a significant challenge, made necessary because of the recent focus on the relationships between traffic, health effects, and ultrafine/nanoparticle toxicity. Further rationale for including size resolution comes from upcoming EPA-mandated changes to diesel sources. Emphasis will be placed on creating an efficient model for general and screening use, rather than a highly detailed model for application to a specific location or exposure setting. It is anticipated that the work product will be well received by funding agencies, public health researchers, and transportation planners.

Mouse Model of Experimental Asthma Using (1->3)-->-B-D- Glucan Derivatives 
Investigators: N. Metwali, P. Thorne, Department of Occupational and Environmental Health, University of Iowa 
Animal models that mimic the pulmonary features observed in human asthma are important tools to study the mechanism(s) of allergen-induced asthma. (1->3)-B-D-Glucans are fungal cell wall polysaccharides that stimulate innate immune responses and are responsible for bioaerosol-induced respiratory symptoms in both indoor and occupational environments. We propose to examine the interaction between different types of glucan (branched and linear) in C3HeB/FeJ mice. We propose exposure of groups of mice to curdlan as a linear (1->3) glucan, pustulan as a linear (1->6) glucan and scleroglucan and laminarin as (1->3)(1->6) branched glucans. This study will bring new understanding to the role of glucans with differing tertiary structure in the induction of inflammation and specific immunity.

Development of a Single Particle Analysis Technique for Real-Time Monitoring and Characterization of Bioaerosols 
Investigator: M. Young, Department of Chemistry, University of Iowa 
We propose to develop an advanced instrument capable of determining the aerodynamic size, approximate shape, and detailed chemical composition of single bioaerosol particles sampled directly from the ambient atmosphere. The correlated data will be used to classify individual particles and provide a detailed characterization of diverse aerosol populations. Sample preparation will be minimal and the analysis sufficiently rapid that identification can be achieved in near real-time. The experimental methodology will integrate advanced solid-state laser sources and mass spectrometric techniques to fashion a powerful and unique instrument. The resultant device will be used in projects to characterize bioaerosols present in the environment, such as in agricultural workplaces, provide a sensitive detection capability for possible biohazards, and monitor bioaerosol transformations induced by chemical processing in the atmosphere. The capabilities of the proposed instrumentation would greatly facilitate epidemiological studies which seek to correlate bioaerosol exposure with deleterious health effects. Technical Report Available.

Polychlorinated Biphenyls are an "Old" Issue:Telomere Toxicity Accelerates Senescence and Promotes Carcinogenesis
Investigators: J. Jacobus, Interdisciplinary Degree in Toxicology, G. Ludewig, Department of Occupational and Environmental Health, A. Klingelhutz, Department of Microbiology, University of Iowa 
Polychlorinated Biphenyls (PCBs) are persistent organic pollutants classified as "probable human carcinogens" by the US Environmental Protection Agency. The exact mechanism of PCB carcinogenesis continues to be elusive. This pilot study proposes techniques for the investigation of a novel target of PCB toxicity, the telomere. Telomeres are rapidly being recognized by scientists as key cellular factors in carcinogenesis, cell-signaling, and senescence. Oxidative stress has been shown to shorten telomeres and therefore reduce the protective buffer they provide to the chromosome. Researchers have implicated oxidative stress as the ultimate carcinogen resultant from PCB exposure. However, no study has examined a telomeric toxicity arising from PCB metabolism. Positive findings in this study could open up an entirely new line of innovative interdisciplinary research, while providing a unifying explanation to the often contradictory findings in PCB carcinogenesis.

Publication:  Senthilkumar PK, Klingelhutz AJ, Jacobus JA, Lehmler H, Robertson LW, Ludewig G; Airborne Polychlorinated Biphenyls (PCBs) Reduce Telomerase Activity and Shorten Telomere Length in Immortal Human Skin Keratinocytes (HaCat). Toxicol Lett. 2011; 204(1):64-70.

The Prevalence and Control of Fragrance Compounds in Iowa Drinking Water 
Investigators: K. Hornbuckle, W. Wombacher, Department of Civil and Environmental Engineering, University of Iowa 
The purpose of this pilot project is to evaluate the effectiveness of water treatment in removing fragrance compounds from drinking water. Synthetic musk fragrances are common additives to many household products. They have been found in wastewater effluent discharge and are considered to be common contaminants in surface waters. The effectiveness of conventional water treatment at removing synthetic fragrances is not well known. Some evidence suggests that removal efficiencies are very poor. This is of concern because many synthetic musk fragrances are endocrine disruptors and may present a health risk to humans. The objectives of this pilot project include: 1) Weekly monitoring at the University of Iowa Water Plant: 2) Determination of removal efficiency; and 3) Evaluation of specific treatment processes.

Publication:  Wombacher WD, Hornbuckle KC; Synthetic Musk Fragrances in a Conventional Drinking Water Treatment Plant with Lime Softening. J Environ Eng (New York). 2009; 135(11): 1192-1198.