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Dive into the research topics where Roger A. Jenkins is active.

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Featured researches published by Roger A. Jenkins.


Inhalation Toxicology | 1994

Sidestream Cigarette Smoke Generation and Exposure System for Environmental Tobacco Smoke Studies

Stephen V. Teague; Kent E. Pinkerton; Michael Goldsmith; Assefa Gebremichael; Sharon A. Chang; Roger A. Jenkins; Jack H. Moneyhun

AbstractPrevious studies of the effects of environmental tobacco smoke have used artificial systems for generating aged and diluted sidestream cigarette smoke. Generally these systems have been designed for large chambers, which require expensive smoking machines, use large air flows, and are labor-intensive. We present a new method for producing sidestream smoke and describe an exposure system for smaller chambers that collects, ages, and dilutes smoke to simulate environmentally relevant conditions. Furthermore, our system is relatively inexpensive, maintains consistent levels of total suspended particulates (TSP) and carbon mon-oxide that can be set at a variety of concentrations, and significantly reduces the manual component of exposure studies.


Journal of Exposure Science and Environmental Epidemiology | 2000

Determination of exposure to environmental tobacco smoke in restaurant and tavern workers in one US city.

Michael P. Maskarinec; Roger A. Jenkins; Richard W. Counts; Amy B. Dindal

Approximately 173 subjects employed as waiters, waitresses, or bartenders in the Knoxville, TN, Standard Metropolitan Statistical Area collected a sample of air from their breathing zone while at their workplace for one shift. In addition, area samples were placed near the work spaces of many of the subjects. Collected samples were analyzed for respirable suspended particulate matter (RSPM), ultraviolet-absorbing and fluorescing particulate matter, solanesol, 3-ethenyl pyridine (3-EP), and nicotine. Saliva samples were collected from the subjects prior to and within 24 h following their work shift, to confirm their non-smoking status. The range of concentrations of environmental tobacco smoke (ETS) constituents encountered was considerable, e.g., for nicotine, from undetectable to more than 100 µg/m3. However, the highest RSP levels observed were considerably lower than OSHA workplace standards. Distributions of ETS concentrations suggest that there are two “ETS exposure” types of bartenders: those that work in single room bars and those that work in larger, multi-room restaurant/bars. Personal exposure to ETS of the former group was ca. 10× greater than those of the latter group, who were exposed to ETS levels more comparable to those encountered by wait staff. Exposure (concentration×duration) differences between wait staff and workers in other types of unrestricted smoking environments reported in other studies suggest that exposures in the restaurant environment may be more difficult to assess than originally considered. Salivary cotinine levels indicated that for those subjects living in smoking homes, ETS exposures outside the workplace are at least as important as those in the workplace.


Atmospheric Environment | 1987

Measuring environmental emissions from tobacco combustion: Sidestream cigarette smoke literature review

M.R. Guerin; C.E. Higgins; Roger A. Jenkins

Abstract The tobacco-derived environmental emission of most common concern is the smoke issuing from cigarettes between puffs. A literature review of smoke formation mechanisms, sampling methods and selected emission factors suggests that sidestream deliveries are actually much less variable than is commonly thought. Examples of devices used to generate and collect sidestream smoke for analysis are described and their advantages and disadvantages discussed. Emissions computed as is common practice from sidestream/mainstream ratios are compared to those determined directly. The ratio method can yield misleading results because of the sensitivity of mainstream deliveries to cigarette and burn characteristics.


Journal of The Air & Waste Management Association | 2004

Development and application of protocols for the determination of response of real-time particle monitors to common indoor aerosols.

Roger A. Jenkins; Ralph H Ilgner; Bruce A. Tomkins; Douglas W. Peters

Abstract Protocols have been developed and applied for the generation of aerosols that are likely to be comparable to those encountered in field settings for the calibration of easily transportable/portable real-time particle monitors. Aerosols generated were simulated environmental tobacco smoke, cedar wood smoke, cooking oil fumes, and propane stove particles. The time-integrated responses of three nephelometers and a monitor for particle-bound polynuclear aromatic hydrocarbons (PAH) were compared with gravimetric respirable suspended particulate matter (RSP) in a controlled-atmosphere chamber. In general, the monitor responses increased linearly with increasing mass concentration. However, the two monitors that reported mass per volume concentrations tended to overreport the actual RSP concentrations by factors up to 4.4. The real-time PAH monitor did not respond to cooking oil fumes, indicative of little PAH being present in the aerosol. One of the monitors that has been used in a variety of studies reported in the literature (DustTrak) was collocated with gravimetric RSP samplers in several hospitality venues in the Louisville, KY, area. Field studies indicated that the units overreported actual RSP concentrations by factors of 2.6–3.1, depending on whether the sampling was conducted in the nonsmoking or smoking sections of the facilities.


Journal of Exposure Science and Environmental Epidemiology | 1999

Personal exposure to environmental tobacco smoke: salivary cotinine, airborne nicotine, and nonsmoker misclassification.

Roger A. Jenkins; Richard W. Counts

A large study was conducted to assess exposure to environmental tobacco smoke (ETS) in a geographically dispersed study population using personal breathing zone air sampling and salivary cotinine levels. Approximately 100 self-reported nonsmoking subjects in each of 16 metropolitan areas were recruited for this investigation. Cumulative distributions of salivary cotinine levels for subjects in smoking and nonsmoking homes and workplaces exhibited a general trend of decreasing salivary cotinine levels with decreasing time spent in smoking environments. Median salivary cotinine levels for the four experimental cells in the study (product of smoking and nonsmoking home and workplaces) were comparable to those reported for a large national study of serum levels of cotinine (Third National Health and Nutrition Examination Survey, NHANES III), when the latter was corrected for expected differences between serum and saliva concentrations. However, the most highly exposed group in this study had a median salivary cotinine concentration approximately a factor of 2 greater than that of the comparable group in the NHANES III study. Misclassification rates, both simple (for self-reported nonsmokers) and complex (self-reported lifetime never smokers), were near the median of those reported for other studies. Estimated misclassification rates for self-reported lifetime never-smoking females are sufficiently high (2.95% using a discrimination level of 106 ng/ml) that, if used in the Environmental Protection Agency (EPA) risk assessment related to ETS and lung cancer, would place the lower 90% confidence interval (CI) for relative risk at nearly 1.00, i.e., no statistically significant increased risk. For the 263 most highly exposed subjects in the study whose self-reported nonsmoking status was accurate, the correlation between airborne exposure to nicotine and average salivary cotinine is so small, on an individual basis, that it makes the relationship useless for estimating exposure on a quantitative basis. When subjects are grouped according to likely categories of nicotine exposure, correlation between group median airborne nicotine exposure and salivary cotinine level increases dramatically. The comparison improves for the most highly exposed subjects, suggesting that such quantitative comparisons are useful for only those subjects who are exposed to the higher levels of ETS. However, airborne nicotine exposure for most of the subjects does not account for estimated systemic levels of nicotine, based on salivary cotinine levels.


Environmental Science & Technology | 1995

Measurement error and spatial variability effects on characterization of volatile organics in the subsurface.

Olivia R. West; Robert L. Siegrist; Toby J. Mitchell; Roger A. Jenkins

The effects of measurement error and spatial variability on establishing subsurface contaminant distributions were demonstrated in a study described herein, where soil underlying a former land treatment facility was intensively sampled and analyzed for volatile organic compounds (VOCs). Concentrations of VOCs measured on-site using a heated headspace/gas chromatography method were typically 10 times higher than concentrations measured at an off-site laboratory using a purge-and-trap/gas chromatography/mass spectrometry method. This was attributed either to VOC losses during storage and preparation of off-site samples and/or inefficient VOC extraction in the off-site method. Three contaminant distribution models developed from the on-site VOC measurements were evaluated through cross-validation and subregion sampling methods. Order of magnitude discrepancies existed between predicted and measured concentrations. These results show that increasing sampling density with cost-effective field analyses can be more effective than using complex spatial models to overcome the lack of spatial information in sparse data sets comprised of off-site laboratory analyses. 25 refs., 8 figs., 2 tabs.


Risk Analysis | 1999

Use of environmental tobacco smoke constituents as markers for exposure.

Judy S. LaKind; Roger A. Jenkins; Daniel Q. Naiman; Michael E. Ginevan; Carol G. Graves; Robert G. Tardiff

The 16-City Study analyzed for gas-phase environmental tobacco smoke (ETS) constituents (nicotine, 3-ethenyl pyridine [3-EP], and myosmine) and for particulate-phase constituents (respirable particulate matter [RSP], ultraviolet-absorbing particulate matter [UVPM], fluorescing particulate matter [FPM], scopoletin, and solanesol). In this second of three articles, we discuss the merits of each constituent as a marker for ETS and report pair-wise comparisons of the markers. Neither nicotine nor UVPM were good predictors for RSP. However, nicotine and UVPM were good qualitative predictors of each other. Nicotine was correlated with other gas-phase constituents. Comparisons between UVPM and other particulate-phase constituents were performed. Its relation with FPM was excellent, with UVPM approximately 1 1/2 times FPM. The correlation between UVPM and solanesol was good, but the relationship between the two was not linear. The relation between UVPM and scopoletin was not good, largely because of noise in the scopoletin measures around its limit of detection. We considered the relation between nicotine and saliva cotinine, a metabolite of nicotine. The two were highly correlated on the group level. That is, for each cell (smoking home and work, smoking home but nonsmoking work, and so forth), there was high correlation between average cotinine and 24-hour time-weighted average (TWA) nicotine concentrations. However, on the individual level, the correlations, although significant, were not biologically meaningful. A consideration of cotinine and nicotine or 3-EP on a subset of the study whose only exposure to ETS was exclusively at work or exclusively at home showed that home exposure was a more important source of ETS than work exposure.


Field Analytical Chemistry and Technology | 1997

Experimental evaluation of two field test kits for the detection of PAHs by immunoassay

Larry C. Waters; Andi Palausky; Richard W. Counts; Roger A. Jenkins

Immunoassay-based field analytical methods are rapidly gaining acceptance by the U.S. Environmental Protection Agency for use in site characterization and remediation. Many analysts, accustomed to using traditional laboratory methods, are reluctant to use immunochemical technology until they are convinced of its effectiveness. Therefore, it is important that experiences with using alternative technologies be shared with the analytical community. In this study, two immunoassay-based field test kits for polyaromatic hydrocarbons (PAHs) were evaluated. One was used in a quantitative format, the other in a semiquantitative format. Samples spiked with a commercial PAH mixture or creosote and field samples including soil and coal-derived liquids were analyzed. For the most effective use of the method, it is important to know the relative response factors (RRFs) for test ana-lytes relative to the kit standards. RRFs for creosote-spiked soil were about 2.3 and 0.11 for the quantitative and semiquantitative tests, respectively. This 20-fold difference in RRF between the two kits held for all the different samples tested and reflects the different antibodies and reference compounds used in the two tests. Potential problems with the integrity of the kit standards, which could significantly affect the interpretation of the test results, are discussed. Recovery of the PAH mixture and creosote from soil ranged from 75 to 90%. The specificity of a third test kit for carcinogenic PAHs was verified with the coal-derived liquids. Overall, both kits gave accurate and reproducible results and were judged to be effective tests for the analysis of PAH contaminated samples.


Journal of Exposure Science and Environmental Epidemiology | 2001

Environmental tobacco smoke in an unrestricted smoking workplace: area and personal exposure monitoring

Roger A. Jenkins; Michael P. Maskarinec; Richard W. Counts; John E. Caton; Bruce A. Tomkins; Ralph H Ilgner

The objective of this investigation was to determine the extent of areal and day-to-day variability of stationary environmental tobacco smoke (ETS) concentrations in a single large facility where smoking was both prevalent and unrestricted, and to determine the degree of daily variation in the personal exposure levels of ETS constituents in the same facility. The subject facility was a relatively new four-story office building with an approximate volume of 1.3 million ft3. The exchange of outside air in the building was determined to be between 0.6 and 0.7 air changes per hour. Eighty-seven area samples (excluding background) were collected at 29 locations over the course of 6 days of sampling. Locations included offices and cubicles occupied by smokers and nonsmokers, common areas, and the computer and mail rooms. Twenty-four nonsmoking subjects wore personal sampling systems to collect breathing zone air samples on each of 3 days in succession. This generated a total of seventy-two 8-h time-weighted average (TWA) personal exposure samples. In all samples, respirable suspended particulate matter, ultraviolet light-absorbing and fluorescing particulate matter, solanesol, nicotine, and 3-ethenyl pyridine were determined. With the exception of a few locations, tobacco-specific airborne constituents were determined in all samples. Not surprisingly, areas with the highest ETS constituent concentrations were offices and cubicles of smokers. Median and 95th percentile concentrations for all area samples, excluding background, were determined to be 1.5 and 8.7 μg/m3 for nicotine, and 8.2 and 59 μg/m3 for ETS-specific particles (as solanesol-related particulate matter, Sol-PM), respectively. Personal exposure concentrations of ETS components were similar to those levels found in the area samples (median nicotine and Sol-PM concentrations were 1.24 and 7.1 μg/m3, respectively), but the range of concentrations was somewhat smaller. For example, the 95th percentile 8-h TWA nicotine and ETS-specific particle (as Sol-PM) concentrations were 3.58 and 21.9 μg/m3, respectively. Intrasubject variation of daily concentrations ranged from 20% to 60%, depending on the component. Self-reported proximity to smokers was supported by higher ETS concentrations determined from the personal monitors, but only to a modest extent. Although smoking was completely unrestricted inside the main office areas of the facility, ETS levels, either areal or from personal exposure measurements, were lower than those estimated by Occupational Safety and Health Administration to be present in such facilities.


Risk Analysis | 1999

Distribution of exposure concentrations and doses for constituents of environmental tobacco smoke

Judy S. LaKind; Michael E. Ginevan; Daniel Q. Naiman; Anthony C. James; Roger A. Jenkins; Michael Dourson; Susan P. Felter; Carol G. Graves; Robert G. Tardiff

The ultimate goal of the research reported in this series of three articles is to derive distributions of doses of selected environmental tobacco smoke (ETS)-related chemicals for nonsmoking workers. This analysis uses data from the 16-City Study collected with personal monitors over the course of one workday in workplaces where smoking occurred. In this article, we describe distributions of ETS chemical concentrations and the characteristics of those distributions (e.g., whether the distribution was log normal for a given constituent) for the workplace exposure. Next, we present population parameters relevant for estimating dose distributions and the methods used for estimating those dose distributions. Finally, we derive distributions of doses of selected ETS-related constituents obtained in the workplace for people in smoking work environments. Estimating dose distributions provided information beyond the usual point estimate of dose and showed that the preponderance of individuals exposed to ETS in the workplace were exposed at the low end of the dose distribution curve. The results of this analysis include estimations of hourly maxima and time-weighted average (TWA) doses of nicotine from workplace exposures to ETS (extrapolated from 1 day to 1 week) and doses derived from modeled lung burdens of ultraviolet-absorbing particulate matter (UVPM) and solanesol resulting from workplace exposures to ETS (extrapolated from 1 day to 1 year).

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Richard W. Counts

Oak Ridge National Laboratory

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Ralph H Ilgner

Oak Ridge National Laboratory

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Amy B. Dindal

Oak Ridge National Laboratory

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Bruce A. Tomkins

Oak Ridge National Laboratory

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Michael P. Maskarinec

Oak Ridge National Laboratory

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Charles K. Bayne

Oak Ridge National Laboratory

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Robert G. Tardiff

National Academy of Sciences

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