PPRT- Current Projects

2022-2023 PPRT Projects

Gap Pre-pulse Inhibition of the Acoustic Startle Reflex for Tinnitus Detection: Wayne State University- Zakaria Enayati

Research Trainee: Zakaria Enayati, PhD Student, Department of Communication Science and Disorders, Wayne State University

Principal Investigator: Avril Holt, Associate Professor, School of Medicine, Wayne State University

Noise is an occupational hazard that is often underestimated by workers. Noisy environments significantly
contribute to hearing and balance related problems, such as hearing loss, tinnitus, hyperacusis, and falls.
Subjective tinnitus affects approximately 15% of the United States population with similar prevalence in
Europe, Asia, and Africa. This condition contributes to many mental health disorders and creates a financial
burden for many experiencing this un-stoppable ringing. Unfortunately, there is not cure for tinnitus. There are
no objective tests to detect tinnitus in humans. Thus, developing an objective, reliable test would substantially
help with the diagnosis and treatment of tinnitus. In animal models of tinnitus, inhibition of the acoustic start le
reflex has been used to detect tinnitus but this test remains controversial in pre-clinical and clinical studies.
Therefore, the proposed studies have been designed to test and compare several parameters of the acoustic
startle reflex in participants with and without tinnitus. The current study aims to assess the ability of normal –
hearing controls and those with tinnitus to inhibit their acoustic startle reflex and determine the correlation of
results with self-reported characteristics of tinnitus.

We hypothesize that, in contrast to normal-hearing participants, tinnitus sufferers will demonstrate a reduced
ability to inhibit their startle response. However, over time, those with tinnitus will maintain the same level of
inhibition, while normal-hearing participants will demonstrate less inhibition.

Total Remote Worker Health: Developing a Remote Assessment Instrument of Physical, Emotional, and Musculoskeletal Health for Individuals who Work From Home: University of Michigan- Jessica Francis

Research Trainee: Jessica Francis, Postdoctoral Fellow, Institute for Social Research, University of Michigan

Research Trainee: Yifan Li, Doctoral Candidate, Industrial & Operations Engineering, University of Michigan

Principal Investigator: Thomas Armstrong, Professor, Industrial & Operations Engineering, University of Michigan

Background: At this point in history, due to the COVID-19 Pandemic, many traditional work settings have now been replaced with new modalities – namely remote work and hybrid work (where individuals can split time between work from home and in person work). In a traditional in-person work modality, the worker is in a more controlled environment, worker behaviors can be observed, and worker tools can often be standardized (for example having the same office chairs for all workers). In a remote or hybrid work environment, the spatial and temporal relationships of the worker become less well-defined, and various aspects of home-life and work-life may start to blend together. Thus, it is important to understand the key benefits and challenges of remote work in relation to the overall health of remote and hybrid workers. Significance: Currently no tools or instruments focus on the total health of workers engaged in primarily remote work or hybrid work. We aim to introduce a tool that can quantify both mental and physical health through an instrument that can be self-administered remotely. Specific Aims: There are three key aims to our proposal 1) Develop a thematic understanding of key barriers and benefits of remote and hybrid work on the overall health of workers; 2) determine applicability and effectiveness of traditional ergonomic assessment tools for assessing remote and hybrid worker fatigue to prevent potential work-related musculoskeletal disorders (WMSDs); and 3) develop and deploy a pilot instrument that assess total remote and hybrid worker well-being and health. Broader Impact: This is a once-in-a-century chance to adopt a paradigm shift of work that can transformatively maximize benefits and minimize problems associated with remote work for both employers and workers. In this planning grant, therefore, we focus on remote work. The developed tool will help inform policy makers and employers of a worker’s mental and physical well-being. In addition, This research will inform policies and recommendations for remote work in the future, as well as evolving hybrid models of work.

Use of Community-based Support Services Among Black Family Dementia Caregivers: University of Michigan- Florence Johnson

Research Trainee & Principal Investigator: Florence Johnson, Ph.D Student, School of Nursing, University of Michigan

Additional Key Personnel: Sheria G. Robinson-Lane, Assistant Professor, School of Nursing, University of Michigan

Dementia family caregivers are becoming an increasingly important part of the caregiver community, assisting with one or more activities of daily life, such as bathing, dressing, toileting, and feeding the person. They also assist with multiple instrumental activities of daily living, such as managing finances, which are common in caregiving. Caregivers provide physical and emotional support to people living with dementia, communicate and organize healthcare, other relatives, and healthcare providers, maintain safety at home and elsewhere, and manage health issues. According to the Alzheimer’s Association, 48% of family caregivers care for someone living with Alzheimer’s Disease and Related Dementias. 

Stress is widespread amongst family caregivers of persons with chronic health conditions. In particular, Black family caregivers of persons living with dementia, compared to their non-Hispanic White counterparts, spend some of the most prolonged caregiving hours and experience some of the highest stress levels. However, little is known about the stress management strategies used by Black dementia family caregivers (B.F.C.) or the support they receive. It is unknown how much support B.F.C.s receive to manage psychological and physical stress. The proposed project aims to determine how community-based support services affect Black F.C.G.s’ mental health and identify barriers and facilitators to caregivers’ use of community-based support services. 

This mixed-method study will use a national dataset of older adults and their caregivers (N.H.A.T.S. and N.S.O.C.) to examine the relationships between Black dementia family caregiver stress, support services use, and health. Further, qualitative interviews with Black dementia family caregivers will examine caregiver experiences in obtaining training and support. Results will inform the development of future interventions that will improve care delivery and health outcomes for both F.C.G.s and persons with A.D.R.D. 

Support for older workers with mobility limitations through indoor work environment interventions: University of Michigan- Kamolnat Tabattanon

Research Trainee: Kamolnat Tabattanon, Ph.D Student, Department of Industrial and Operations Engineering, Center for Ergonomics, University of Michigan

Principal Investigator: Bernard J. Martin, Associate Professor, Department of Industrial and Operations Engineering, Center for Ergonomics, University of Michigan

The population and proportion of older adults (age 65+ years) is increasing in the US. Alongside this trend, Americans are increasingly working into older age, with 20% of older adults either working or looking for work[30]. To safely accommodate the projected rise in older workers, it is critical to account for the intersection of old age and mobility disability, as mobility disability incidence is increasing among aging adults[1]. Manual wheelchair support for balance and mobility will be on the rise, though workers who transition to manual wheelchair use will be able to retain independence in movement and upper extremity tasks provided the environment-task demands are designed for inclusion[22, 24]. By addressing this subgroup of older adults with later-in-life incidence of disability, work environment evaluations can become more sustainably inclusive. Current work environments are lacking in this regard, as 22% of older adults with disabilities who ceased seeking work stopped due to discouragement, including from perceived discrimination for age and/or disability[5]. Of further concern, recent studies suggest that disability populations are prone to underreporting their own difficulties when evaluating designs with traditional subjective measures [18, 34]. Yet the use of objective measures (e.g., biomechanics, task times) can be costly during design development. Better alignment between subjective ratings and objective performance can (1) result in designs that promote self-efficacy and remove psychosocial barriers; and (2) support future environment-task design processes towards broader inclusion. 

Therefore, we will investigate mobility performance between those with earlier-in-life (EL) and later-in-life (LL) incidence of manual wheelchair usage. Here, performance in an independent path following task is divided into assumed performance (how participants expect to perform), perceived performance (how participants think they performed), and effective performance (how objective measures quantify their completed performance). By comparing these categories, we will investigate internal representation of motor actions and test differences between groups. This will inform ways to support mobility through environmental indications as well as ways to supplement potentially biased subjective estimations in environmental evaluations. It is postulated that representation of the world as a function of assumed mobility impairment/deficiency is a factor in self-limiting mobility. 

2021-2022 PPRT Projects

Design of Computer-Vision Based System for Immediate Multi-Person Ergonomics Assessment in Veterinary Practice: Purdue University- Jing Yang

Research Trainee: Jing Yang, PhD Student, School of Industrial Engineering, Purdue University

Principal Investigator: Denny Yu, Assistant Professor, School of Industrial Engineering, Purdue University

Co-Principal Investigator: Sun Young Kim, Associate Professor, Department of Veterinary Clinical Sciences, Purdue University

Jing Yang, Research Trainee

Denny Yu, PhD, Principal Investigator

Compared with other occupations, veterinary medicine and animal care (VMAC) has the 2nd highest incidence rate for nonfatal occupational injuries and illnesses1. However, limited  work has been done to understand and address the unique contributors to injuries in VMAC. Despite the availability of observer-based checklists and sensor-based techniques, they may not best approaches for ergonomic risk factors assessment due to their interference with workflow. To have an easy- to-use, accurate, and efficient ergonomic risk assessment in real-world operational environments, several research gaps need to be addressed; specifically, 1) non-intrusive techniques for continuous work ergonomics assessment and 2) intervention tools to engage current VMAC workers on the already-present injury risk factors in the workplace. To fill the gap in this field, we propose a novel ergonomic risk management tool using computer vision that performs robust, constant, and automatic ergonomic assessment for multiple veterinary practitioners, either individually or collectively, under challenging acquisition conditions without the need for wearables.

Toxicity Assessment of Welding Fume Metal Nanoparticle Components: Purdue University- Li Xia

Research Trainee: Li Xia, Predoctoral Candidate, School of Health Sciences, Purdue University

Principal Investigator: Jonathan Shannahan, Assistant Professor, School of Health Sciences, Purdue University

Jonathan Shannahan, PhD, Principal Investigator

Li Xia, Research Trainee

Welding is an essential modern manufacturing technology, with 11 million welders worldwide and 110 million individuals exposed to welding fumes at their workplace. Importantly, there exists an occupational exposure risk to welding fume exposures with studies demonstrating exposure-related lung dysfunction, asthma, bronchitis, cancer, and increased susceptibility to pulmonary infections. Welding fumes are a complex mixture consisting of primarily metal NPs, such as iron (Fe), manganese (Mn), and others. These metal NPs are able to deposit deep within the lung inducing oxidative stress and inflammation resulting in pulmonary injury. Toxicity resulting from welding fume exposure is likely variable based on alterations in NP components of the fumes. Additionally, welders are known to be increasingly susceptible to pulmonary bacterial and viral infections due to exposure-induced immune dysregulation. This modulation of the immune system may also reduce viral vaccine effectiveness in this population. To examine toxicity associated with variations in NP components of welding fumes, we constructed a system for the controlled and continuous generation of NPs from welding electrodes for in vitro exposure studies. For the proposed study, NP mixtures will be produced from highly utilized commercially available electrodes (6010, 6012, 7024). To perform hazard assessments of the NP components, human lung epithelial cells and macrophages will be grown individually and transitioned to air-liquid-interface. Human fibroblasts will be grown in the basolateral compartment and will interact with signaling molecules released from cells in air-liquid-interface. NP aerosols will be characterized in real-time during exposures for size, composition, and morphology. Cells will be exposed to two human-relevant concentrations of freshly aerosolized NPs for 8 h and endpoints of toxicity will be evaluated. In aim 1, cells will be examined for differential toxicity due to alterations in aerosolized NP components. The endpoints analyzed include cytotoxicity, internalization of NPs, and alterations in markers of oxidative stress, inflammation, and fibrosis. Aim 2 will evaluate bacterial and viral susceptibility risks following welding fume exposures through challenging exposed cells with lipopolysaccharide (LPS) to model gram-negative bacteria or the live attenuated influenza virus (FluMist). Completion of this proposed research will result in the generation of new knowledge regarding hazards associated with the NP component of welding fumes and their impact on infection risk. This information will allow for a more thorough understanding of disease associated with occupational exposure to welding fumes and can be applied to regulations, prevention strategies, and therapeutic strategies.

Prevention of Needlestick Injuries Among Healthcare Workers in Liberia and Ghana: A Cross-Sectional Mixed Methods Study: University of Michigan- Laura Ridge

Research Trainee: Laura Jean Ridge, Postdoctoral Fellow in Complexity: Innovations in Promoting Health and Safety (CIPHS), University of Michigan School of Nursing

Principal Investigator: Majorie McCullagh, Sally L. Lusk Collegiate Professor of Nursing, Occupational Health Nursing Program Director, University of Michigan School of Nursing

Laura Jean Ridge, Research Trainee

Marjorie McCullagh, Principal Investigator

Needlestick injuries (NSIs) are a major occupational hazard for healthcare workers worldwide. The majority of NSIs take place in low- and middle-income countries (LMICs), but surveillance of NSIs in LMICs is limited. Preliminary data indicate that Liberia and Ghana, both English- speaking, low-income countries in West Africa, have different NSI incidence and reporting, but it is not understood why, largely due to limited understanding of modifiable and non-modifiable risk factors.

This explanatory sequential mixed-methods study will use both cross-sectional survey and interview data of healthcare workers to examine different NSI outcomes (injury management, reporting, follow-up). Survey data will be analyzed using descriptive and inferential statistics; interview data will be analyzed via content analysis. After being analyzed separately, survey and interview data will be merged to explore the experiences of workers with >2 NSIs in a year and workers who have not reported their NSIs.

Results of this study will include the incidence of NSI among healthcare workers in these two countries, the rates of reporting, and the role of modifiable and non-modifiable risk factors in NSIs. Conclusion: Results of this study may be used to identify characteristics of particularly vulnerable workers and suggest ways to protect them; it may also be used to identify important modifiable risk factors in the general worker population.

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Evaluating Occupational Biohazards, Stress, and Readiness for Uptake of Total Worker Health Interventions in U.S. Waste Workers: University of Michigan - Aurora Le

Research Mentor: Richard Neitzel, PhD, MS, CIH, FAIHA, Associate Professor, Department of Environmental Health Sciences, School of Public Health, University of Michigan

Principal Investigator: Aurora Le, PhD, MPH, CSP, CPH, Assistant Professor, Department of Environmental Health Sciences, School of Public Health, University of Michigan

Aurora Le, PhD, Assistant Professor

Rick Neitzel, PhD, Associate Professor

Waste workers experience occupational hazards daily. Particularly, solid and medical waste workers are exposed to bioaerosols, bloodborne pathogens, and human and animal excrements in the process of collecting, sorting, and disposing waste. In tandem, the constant chronic biological occupational exposures can result in elevated stress. Occupational stress, in turn, can result in increased injury and illness rates among workers. Significant research, both in and outside of the United States, has been conducted on waste workers regarding their chemical and ergonomic occupational exposures. However, information about the biological exposures of U.S. waste workers and their associated workplace stress is limited despite comparable risks to biohazards as healthcare workers. Evidence suggests that Total Worker Health (TWH) approaches are efficacious in addressing both the physical and psychosocial stressors of the workplace, but to our knowledge, this has not been explored among U.S. waste workers. Consequently, the proposed pilot study aims to address the aforementioned research gaps. We propose a comprehensive assessment of a sample of U.S. solid and medical waste workers to determine occupational biohazard exposures and knowledge and training to mitigate these hazards. Additionally, perceived occupational stress and readiness for uptake of TWH interventions will be measured using existing validated assessment tools. Perceived self- reported stress will be compared to the worker’s physiological stress via collection of saliva samples to analyze cortisol levels. The proposed study will create the foundation for a long-term collaboration between the university researchers and national stakeholders in the waste industry. Furthermore, it will generate pilot data for use in future development of TWH interventions, as well as bolstered biohazard training and education to improve the health, safety, and wellbeing of this overlooked yet vulnerable population of workers in solid and medical waste.

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Chlorinated Naphthalenes in Human Plasma: Occupational Exposure Assessment Using Biomonitoring and Self-Reported Exposure Data in a Michigan Cohort: University of Michigan- Stuart Batterman

Research Trainee: Amila Devasurendra, Research Lab Specialist Senior, Department of Environmental Health Sciences, School of Public Health, University of Michigan

Principal Investigator: Stuart Batterman, PhD, Professor, Department of Environmental Health Sciences, School of Public Health, University of Michigan

Amila Devasurendra, Research Trainee

Stuart Batterman, Principal Investigator

The overall objective of the proposed project is to improve occupational exposure assessments for emerging toxic contaminants, specifically, polychlorinated naphthalenes (PCNs), which have been recently listed under the Stockholm Convention and for which little exposure data exists in the USA or worldwide. PCNs are a class of chlorinated polycyclic aromatic hydrocarbons (PAHs) that are present in many industrial chemicals and by-products. They include 75 congeners, several of which are highly toxic, bioaccumulative and persistent. The proposed project will focus on (1) the development and validation of a sensitive method to detect and quantify PCNs by homologue group and selected congeners, focusing on the most prevalent and toxic species in biological specimens such as blood or plasma; (2) application of the method using archived plasma samples to develop preliminary statistics on PCN exposures in Michigan workers; and (3) comparison of biological monitoring results with occupational histories previously obtained for each Michigan worker to potentially identify specific jobs or activities associated with PCN exposure. In addition, the proposed study will provide advanced training in occupational exposure assessment methods to a junior researcher. The study will utilize biological samples and survey data that have been previously collected and appropriately stored, and which form part of a large case-control study of amyotrophic lateral sclerosis (ALS); these data form part of the University of Michigan ALS Patient Repository (UMAPR). Currently, the repository includes data and biospecimens from over 800 ALS patients and healthy controls drawn across Michigan. The study will, for the first time, explore the presence of PCNs in a cross-section of US workers, will utilize both surveys and biological monitoring data, which can address gaps in each method, and most significantly, lead to a better understanding of PCN exposure and risk.

PPRT Director:

Adam M. Finkel, Sc. D., CIH
Clinical Professor of Environmental Health Sciences