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Active Research

Diesel Exposure in Mines: Biomarkers in Urine and Realtime Air Monitoring

Dr. Dale Stephenson and Dr. Chris Simpson are co-principal investigators on a $405,301 exploratory grant from the National Institute for Occupational Safety and Health (NIOSH) under the Centers for Disease Control and Prevention.

Dr. Dale Stephenson and research assistant Emily Zamzow performing tests on a miner for diesel exposure in a Montana mine

Dr. Dale Stephenson and research assistant Emily Zamzow performing tests on a miner for diesel exposure in a Montana mine

The overall goal of the project titled ‘Diesel Exposure in Mines: Biomarkers in Urine and Real-time Air Monitoring’ is to evaluate novel approaches for assessing the exposure of underground miners to Diesel Exhaust. Diesel exhaust (DE) represents a major source of fine particulate matter air pollution (PM), and has been associated with both acute and chronic health effects. Elevated exposure to DE has been linked to irritation of the eyes, nose, throat and respiratory system, in addition to inflammatory responses within the respiratory system. Based on the totality of evidence from human, animal and other studies, the EPA concluded that DE is likely to cause cancer by inhalation, and that evidence is strongly supportive of a causal association with lung cancer (US EPA 2002). Due to the nature of their work in confined spaces and in close proximity to diesel powered equipment, underground miners experience the highest exposures to DE of any occupation. Thus, miners are at high risk for suffering adverse health effects associated with DE exposure.

The new exposure monitoring approaches to be tested in this project are anticipated to provide improved estimation of miner’s exposure to DE over both an acute and chronic timescale – likely at significantly lower cost than current technology. The improved exposure assessment will, in turn, permit evaluation of the effectiveness of recent interventions to reduce miner’s exposures to DE (e.g. introduction of biodiesel and engine emission control devices) and reduce the burden of disease associated with these exposures.

This project represents a research partnership between the University of Washington, Boise State University, and Montana Tech. Dr. Sin Ming Loo (Professor and Department Chair) from the Electrical and Computer Engineering Department at Boise State University is also a co-investor on this project.
This material is based on work supported by the Centers for Disease Control and Prevention under Grant number 1R21OH010362-01A1.

STAC-TEC Sustainable Technologies and Alternative Chemistries
STAT TechDr. Dale Stephenson is a Co-Investigator on a $600,000 NIEHS R25 award that creates a Sustainable Technologies and Alternative Chemistries – Training and Education Center.  As a part of this award the SES lab will focus on workplace health and safety risks associated with several emerging technologies: biotechnology, nanotechnology, alternative chemistries, and waste reclamation. The target audience for the center activities will be students and professionals in areas of both technology development and occupational and environmental health sciences: civil and environmental engineering, chemical engineering, exposure sciences, environmental health sciences, nursing, and occupational medicine. We will focus training efforts on identification and evaluation of potential health risks to workers and the environment, and on developing appropriate controls and substitution strategies that can provide long-term solutions that make these “sustainable technologies” in terms of minimizing potential harmful waste streams, reducing process hazards and energy costs. Successful implementation of this training approach will provide broad awareness and knowledge in the workplace of Sustainable Technologies and Alternative Chemistries (STAC) among people engaged in scientific discovery, process development, product engineering, and worker health and safety.
 This material is based on work supported by the Centers for Disease Control and Prevention under Grant number 1R25ES023632-01

Recently Completed Research

Snowmobile Noise Exposure Monitoring of Yellowstone National Park Employees

Yellowstone Snow Mobile_Noise Exposure

The many snowmobiles used to conduct research in Yellowstone National Park for noise exposure

In Yellowstone National Park (YNP) the use of snow machines has risen sharply since 1949.  Paralleling the rise in snow machine travel were concerns over increases in noise emissions which, resulted in the establishment of winter-use plans for YNP.  As yearly iterations of winter-use plans began to appear, input was needed concerning noise exposures received by YNP employees regulating snow machine traffic entering the Park.  This study provides noise monitoring results of snow machines traffic at the west entrance to YNP.  The study objectives were to characterize noise exposures received by YNP employees and to evaluate these exposures relative to Occupational Safety and Health Administration (OSHA) standards.  Concerning area and personal monitoring of YNP employees supervising snow machine traffic, study results suggest compliance with OSHA regulations.  This is also true when applying a more conservative approach to estimate daily noise exposure. In contrast, many of the monitoring results estimating noise exposures received by YNP employees operating snowmobiles were close to or exceeded the OSHA noise standard.  While the findings associated with snowmobile operators serve to provide awareness of the potential for adverse exposures, limitations concerning these exposure estimates are discussed and point to the need for additional monitoring using more precise methods.  Given the likelihood that winter-use plans for YNP will continue to evolve, it is anticipated that the results of this study will provide information that can be incorporated into future winter-use plans aimed, in part, at better management of occupational noise exposure and the protection of employee health.

Quantification of CO Exposures Associated with the Operation of Recreational Watercraft

A researcher testing the carbon monoxide emission associated with a recreational watercraft

A researcher testing the carbon monoxide emission associated with a recreational watercraft

Carbon monoxide (CO) is a colorless and odorless gas generated from the incomplete combustion of hydrocarbon-based fuels.  Sources of CO emissions include gasoline powered engines and portable generators, natural gas appliances, kerosene space heaters, and wood stoves.  Medical research has shown that human exposure to elevated concentrations of CO can cause serious injury or death. Of increasing concern are CO-related poisonings and fatalities associated with the use of recreational watercraft.  Since 1981 there have been 661 reported poisonings and 149 fatalities identified as a result of overexposure to CO during the operation of recreational watercraft in the United States.

Dale in Boat

Dr. Dale Stephenson conducting research on the water of the associated amounts of carbon monoxide exposure while using watercraft

This research characterized the risks and dangers that recreational watercraft users may face from CO exposure. Currently there is a lack of awareness of this issue among the general public.  Because CO is colorless and odorless, and because watercraft usage is outdoors with seemingly adequate ventilation, many people are not aware that hazardous exposure to CO can occur.

To adequately characterize the risk of encountering adverse CO exposures thirty one (31) fixed locations on and around four types of watercraft were monitored using realtime and time-integrated instrumentation. In addition, CO monitoring was performed during the recreational activities of wake surfing and lounging on the stern’s swim platform.