Last data update: Apr 22, 2024. (Total: 46599 publications since 2009)
Records 1-19 (of 19 Records) |
Query Trace: Toennis C [original query] |
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Characterization of inhalation exposures at a wildfire incident during the Wildland Firefighter Exposure and Health Effects (WFFEHE) Study
Navarro KM , Fent K , Mayer AC , Brueck SE , Toennis C , Law B , Meadows J , Sammons D , Brown S . Ann Work Expo Health 2023 67 (8) 1011-1017 Wildland firefighters (WFFs) are exposed to many inhalation hazards working in the wildland fire environment. To assess occupational exposures and acute and subacute health effects among WFFs, the wildland firefighter exposure and health effects study collected data for a 2-year repeated measures study. This manuscript describes the exposure assessment from one Interagency Hotshot Crew (N = 19) conducted at a wildfire incident. Exposures to benzene, toluene, ethylbenzene, xylene isomers, formaldehyde, acetaldehyde, and naphthalene were measured through personal air sampling each work shift. Biological monitoring was done for creatinine-adjusted levoglucosan in urine pre- and post-shift. For 3 days sampling at the wildfire incident, benzene, toluene, ethylbenzene, xylene isomers (m and p, and o) exposure was highest on day 1 (geometric mean [GM] = 0.015, 0.042, 0.10, 0.42, and 0.15 ppm, respectively) when WFFs were not exposed to smoke but used chainsaws to remove vegetation and prepare fire suppression breaks. Exposure to formaldehyde and acetaldehyde was highest on day 2 (GM = 0.03 and 0.036 ppm, respectively) when the WFFs conducted a firing operation and were directly exposed to wildfire smoke. The greatest difference of pre- and post-shift levoglucosan concentrations were observed on day 3 (pre-shift: 9.7 and post-shift: 47 μg/mg creatinine) after WFFs conducted mop up (returned to partially burned area to extinguish any smoldering vegetation). Overall, 65% of paired samples (across all sample days) showed a post-shift increase in urinary levoglucosan and 5 firefighters were exposed to benzene at concentrations at or above the National Institute for Occupational Safety and Health (NIOSH) recommended exposure limit. Our findings further demonstrate that exposure to inhalation hazards is one of many risks that wildland firefighters experience while suppressing wildfires. |
Evaluating exposure to VOCs and naphthalene for firefighters wearing different ppe configurations through measures in air, exhaled breath, and urine
Mayer AC , Fent KW , Wilkinson AF , Chen IC , Siegel MR , Toennis C , Sammons D , Meadows J , Kesler RM , Kerber S , Smith DL , Masoud F , Bhandari D , Wang Y , Blount BC , Calafat AM , Horn GP . Int J Environ Res Public Health 2023 20 (12) Firefighters are at an increased risk of cancer due to their occupational exposure to combustion byproducts, especially when those compounds penetrate the firefighter personal protective equipment (PPE) ensemble. This has led to questions about the impact of base layers (i.e., shorts vs. pants) under PPE ensembles. This study asked 23 firefighters to perform firefighting activities while wearing one of three different PPE ensembles with varying degrees of protection. Additionally, half of the firefighters unzipped their jackets after the scenario while the other half kept their jackets zipped for five additional minutes. Several volatile organic compound (VOC) and naphthalene air concentrations outside and inside of hoods, turnout jackets, and turnout pants were evaluated; biological (urinary and exhaled breath) samples were also collected. VOCs and naphthalene penetrated the three sampling areas (hoods, jackets, pants). Significant (p-value < 0.05) increases from pre- to post-fire for some metabolites of VOCs (e.g., benzene, toluene) and naphthalene were found. Firefighters wearing shorts and short sleeves absorbed higher amounts of certain compounds (p-value < 0.05), and the PPE designed with enhanced interface control features appeared to provide more protection from some compounds. These results suggest that firefighters can dermally absorb VOCs and naphthalene that penetrate the PPE ensemble. |
Firefighters' urinary concentrations of VOC metabolites after controlled-residential and training fire responses
Fent KW , Mayer AC , Toennis C , Sammons D , Robertson S , Chen IC , Bhandari D , Blount BC , Kerber S , Smith DL , Horn GP . Int J Hyg Environ Health 2022 242 113969 INTRODUCTION: Firefighters are exposed to volatile organic compounds (VOCs) during structural fire responses and training fires, several of which (e.g., benzene, acrolein, styrene) are known or probable carcinogens. Exposure studies have found that firefighters can absorb chemicals like benzene even when self-contained breathing apparatus (SCBA) are worn, suggesting that dermal absorption contributes to potentially harmful exposures. However, few studies have characterized VOC metabolites in urine from firefighters. OBJECTIVES: We quantified VOC metabolites in firefighters' urine following live firefighting activity across two field studies. METHODS: In two separate controlled field studies, spot urine was collected before and 3 h after firefighters and firefighter students responded to simulated residential and training fires. Urine was also collected from instructors from the training fire study before the first and 3 h after the last training scenario for each day (instructors led three training scenarios per day). Samples were analyzed for metabolites of VOCs to which firefighters may be exposed. RESULTS: In the residential fire study, urinary metabolites of xylenes (2MHA), toluene (BzMA), and styrene (MADA) increased significantly (at 0.05 level) from pre- to post-fire. In the training fire study, MADA concentrations increased significantly from pre- to post-fire for both firefighter students and instructors. Urinary concentrations of benzene metabolites (MUCA and PhMA) increased significantly from pre- to post-fire for instructors, while metabolites of xylenes (3MHA+4MHA) and acrolein (3HPMA) increased significantly for firefighter students. The two highest MUCA concentrations measured post-shift from instructors exceeded the BEI of 500 μg/g creatinine. CONCLUSIONS: Some of the metabolites that were significantly elevated post-fire are known or probable human carcinogens (benzene, styrene, acrolein); thus, exposure to these compounds should be eliminated or reduced as much as possible through the hierarchy of controls. Given stringent use of SCBA, it appears that dermal exposure contributes in part to the levels measured here. |
The Wildland Firefighter Exposure and Health Effect (WFFEHE) Study: Rationale, design, and methods of a repeated-measures study
Navarro KM , Butler CR , Fent K , Toennis C , Sammons D , Ramirez-Cardenas A , Clark KA , Byrne DC , Graydon PS , Hale CR , Wilkinson AF , Smith DL , Alexander-Scott MC , Pinkerton LE , Eisenberg J , Domitrovich JW . Ann Work Expo Health 2021 66 (6) 714-727 The wildland firefighter exposure and health effect (WFFEHE) study was a 2-year repeated-measures study to investigate occupational exposures and acute and subacute health effects among wildland firefighters. This manuscript describes the study rationale, design, methods, limitations, challenges, and lessons learned. The WFFEHE cohort included fire personnel ages 18-57 from six federal wildland firefighting crews in Colorado and Idaho during the 2018 and 2019 fire seasons. All wildland firefighters employed by the recruited crews were invited to participate in the study at preseason and postseason study intervals. In 2019, one of the crews also participated in a 3-day midseason study interval where workplace exposures and pre/postshift measurements were collected while at a wildland fire incident. Study components assessed cardiovascular health, pulmonary function and inflammation, kidney function, workplace exposures, and noise-induced hearing loss. Measurements included self-reported risk factors and symptoms collected through questionnaires; serum and urine biomarkers of exposure, effect, and inflammation; pulmonary function; platelet function and arterial stiffness; and audiometric testing. Throughout the study, 154 wildland firefighters participated in at least one study interval, while 144 participated in two or more study interval. This study was completed by the Centers for Disease Control and Prevention's National Institute for Occupational Safety and Health through a collaborative effort with the U.S. Department of Agriculture Forest Service, Department of the Interior National Park Service, and Skidmore College. Conducting research in the wildfire environment came with many challenges including collecting study data with study participants with changing work schedules and conducting study protocols safely and operating laboratory equipment in remote field locations. Forthcoming WFFEHE study results will contribute to the scientific evidence regarding occupational risk factors and exposures that can impact wildland firefighter health over a season and across two wildland fire seasons. This research is anticipated to lead to the development of preventive measures and policies aimed at reducing risk for wildland firefighters and aid in identifying future research needs for the wildland fire community. |
Characterizing exposures to flame retardants, dioxins, and furans among firefighters responding to controlled residential fires
Mayer AC , Fent KW , Chen IC , Sammons D , Toennis C , Robertson S , Kerber S , Horn GP , Smith DL , Calafat AM , Ospina M , Sjodin A . Int J Hyg Environ Health 2021 236 113782 Firefighters may encounter items containing flame retardants (FRs), including organophosphate flame retardants (OPFRs) and polybrominated diphenyl ethers (PBDEs), during structure fires. This study utilized biological monitoring to characterize FR exposures in 36 firefighters assigned to interior, exterior, and overhaul job assignments, before and after responding to controlled residential fire scenarios. Firefighters provided four urine samples (pre-fire and 3-h, 6-h, and 12-h post-fire) and two serum samples (pre-fire and approximately 23-h post-fire). Urine samples were analyzed for OPFR metabolites, while serum samples were analyzed for PBDEs, brominated and chlorinated furans, and chlorinated dioxins. Urinary concentrations of diphenyl phosphate (DPhP), a metabolite of triphenyl phosphate (TPhP), bis(1,3-dichloro-2-propyl) phosphate (BDCPP), a metabolite of tris(1,3-dichloro-2-propyl) phosphate (TDCPP), and bis(2-chloroethyl) phosphate (BCEtP), a metabolite of tris(2-chloroethyl) phosphate (TCEP), increased from pre-fire to 3-hr and 6-hr post-fire collection, but only the DPhP increase was statistically significant at a 0.05 level. The 3-hr and 6-hr post-fire concentrations of DPhP and BDCPP, as well as the pre-fire concentration of BDCPP, were statistically significantly higher than general population levels. BDCPP pre-fire concentrations were statistically significantly higher in firefighters who previously participated in a scenario (within the past 12 days) than those who were responding to their first scenario as part of the study. Similarly, firefighters previously assigned to interior job assignments had higher pre-fire concentrations of BDCPP than those previously assigned to exterior job assignments. Pre-fire serum concentrations of 2,3,4,7,8-pentachlorodibenzofuran (23478-PeCDF), a known human carcinogen, were also statistically significantly above the general population levels. Of the PBDEs quantified, only decabromodiphenyl ether (BDE-209) pre- and post-fire serum concentrations were statistically significantly higher than the general population. These results suggest firefighters absorbed certain FRs while responding to fire scenarios. |
Association of occupational exposures with ex vivo functional immune response in workers handling carbon nanotubes and nanofibers
Schubauer-Berigan MK , Dahm MM , Toennis CA , Sammons DL , Eye T , Kodali V , Zeidler-Erdely PC , Erdely A . Nanotoxicology 2020 14 (3) 1-16 The objective of this study was to evaluate the association between carbon nanotube and nanofiber (CNT/F) exposure and ex vivo responses of whole blood challenged with secondary stimulants, adjusting for potential confounders, in a cross-sectional study of 102 workers. Multi-day exposure was measured by CNT/F structure count (SC) and elemental carbon (EC) air concentrations. Demographic, lifestyle and other occupational covariate data were obtained via questionnaire. Whole blood collected from each participant was incubated for 18 hours with and without two microbial stimulants (lipopolysaccharide/LPS and staphylococcal enterotoxin type B/SEB) using TruCulture technology to evaluate immune cell activity. Following incubation, supernatants were preserved and analyzed for protein concentrations. The stimulant:null response ratio for each individual protein was analyzed using multiple linear regression, followed by principal component (PC) analysis to determine whether patterns of protein response were related to CNT/F exposure. Adjusting for confounders, CNT/F metrics (most strongly, the SC-based) were significantly (p < 0.05) inversely associated with stimulant:null ratios of several individual biomarkers: GM-CSF, IFN-gamma, interleukin (IL)-2, IL-4, IL-5, IL-10, IL-17, and IL-23. CNT/F metrics were significantly inversely associated with PC1 (a weighted mean of most biomarkers, explaining 25% of the variance in the protein ratios) and PC2 (a biomarker contrast, explaining 14%). Among other occupational exposures, only solvent exposure was significant (inversely related to PC2). CNT/F exposure metrics were uniquely related to stimulant responses in challenged whole blood, illustrating reduced responsiveness to a secondary stimulus. This approach, if replicated in other exposed populations, may present a relatively sensitive method to evaluate human response to CNT/F or other occupational exposures. |
Firefighters' and instructors' absorption of PAHs and benzene during training exercises
Fent KW , Toennis C , Sammons D , Robertson S , Bertke S , Calafat AM , Pleil JD , Geer Wallace MA , Kerber S , Smith DL , Horn GP . Int J Hyg Environ Health 2019 222 (7) 991-1000 INTRODUCTION: Training fires may constitute a major portion of some firefighters' occupational exposures to smoke. However, the magnitude and composition of those exposures are not well understood and may vary by the type of training scenario and fuels. OBJECTIVES: To understand how structure fire training contributes to firefighters' and instructors' select chemical exposures, we conducted biological monitoring during exercises involving combustion of pallet and straw and oriented strand board (OSB) or the use of simulated smoke. METHODS: Urine was analyzed for metabolites of polycyclic aromatic hydrocarbons (PAHs) and breath was analyzed for volatile organic compounds (VOCs) including benzene. RESULTS: Median concentrations of nearly all PAH metabolites in urine increased from pre-to 3-hr post-training for each scenario and were highest for OSB, followed by pallet and straw, and then simulated smoke. For instructors who supervised three trainings per day, median concentrations increased at each collection. A single day of OSB exercises led to a 30-fold increase in 1-hydroxypyrene for instructors, culminating in a median end-of-shift concentration 3.5-fold greater than median levels measured from firefighters in a previous controlled-residential fire study. Breath concentrations of benzene increased 2 to 7-fold immediately after the training exercises (with the exception of simulated smoke training). Exposures were highest for the OSB scenario and instructors accumulated PAHs with repeated daily exercises. CONCLUSIONS: Dermal absorption likely contributed to the biological levels as the respiratory route was well protected. Training academies should consider exposure risks as well as instructional objectives when selecting training exercises. |
Firefighters' absorption of PAHs and VOCs during controlled residential fires by job assignment and fire attack tactic
Fent KW , Toennis C , Sammons D , Robertson S , Bertke S , Calafat AM , Pleil JD , Wallace MAG , Kerber S , Smith D , Horn GP . J Expo Sci Environ Epidemiol 2019 30 (2) 338-349 To better understand the absorption of combustion byproducts during firefighting, we performed biological monitoring (breath and urine) on firefighters who responded to controlled residential fires and examined the results by job assignment and fire attack tactic. Urine was analyzed for metabolites of polycyclic aromatic hydrocarbons (PAHs) and breath was analyzed for volatile organic compounds (VOCs) including benzene. Median concentrations of PAH metabolites in urine increased from pre-firefighting to 3-h post firefighting for all job assignments. This change was greatest for firefighters assigned to attack and search with 2.3, 5.6, 3.9, and 1.4-fold median increases in pyrene, phenanthrene, naphthalene, and fluorene metabolites. Median exhaled breath concentrations of benzene increased 2-fold for attack and search firefighters (p < 0.01) and 1.4-fold for outside vent firefighters (p = 0.02). Compared to interior attack, transitional attack resulted in 50% less uptake of pyrene (p = 0.09), 36% less uptake phenanthrene (p = 0.052), and 20% less uptake of fluorene (p < 0.01). Dermal absorption likely contributed to firefighters' exposures in this study. Firefighters' exposures will vary by job assignment and can be reduced by employing a transitional fire attack when feasible. |
Survey of guidelines and current practices for safe handling of antineoplastic and other hazardous drugs used in 24 countries
Mathias PI , MacKenzie BA , Toennis CA , Connor TH . J Oncol Pharm Pract 2017 25 (1) 1078155217726160 Purpose A survey of guidelines and current practices was conducted to examine the safe handling procedures for antineoplastic and other hazardous drugs that are used in 24 countries including the Americas, Europe, the Mideast, Far East, and Australia. Methods Subject experts were asked to complete a brief survey regarding safe handling guidelines and practices for hazardous drugs in their countries. Questions addressed practices for handling monoclonal antibodies, the use of closed-system transfer devices, medical surveillance practices, and measurements of compliance with existing guidelines. Results Responses from 37 subject experts representing 24 countries revealed considerable variation in the content and scope of safe handling guidelines and pharmacy practices among the participating countries. Guidelines in the majority of countries used the term "cytotoxics," while others referred to "hazardous" or "antineoplastic" drugs. The International Society of Oncology Pharmacy Practice standard was cited by six countries, and five cited the National Institute for Occupational Safety and Health Alert. Others cited international guidelines other than International Society of Oncology Pharmacy Practice, or they have created their own guidelines. Approximately half reported that their guidelines were mandatory under federal, state, or provincial legislation. Only 11 countries reported that monoclonal antibodies were covered in their guidelines. Closed-system drug-transfer devices are widely used, but were not specifically recommended in four countries, while one country required their use. Medical surveillance programs are in place in 20 countries, but only in The Netherlands is surveillance mandatory. Nine countries reported that they have completed recent updates or revisions of guidelines, and the measures for their adoption have been initiated. Conclusions Although the overall goals in the participating countries were similar, the approaches taken to assure safe handling of hazardous drugs varied considerably in some cases. |
Contamination of firefighter personal protective equipment and skin and the effectiveness of decontamination procedures
Fent KW , Alexander B , Roberts J , Robertson S , Toennis C , Sammons D , Bertke S , Kerber S , Smith D , Horn G . J Occup Environ Hyg 2017 14 (10) 0 Firefighters' skin may be exposed to chemicals via permeation/penetration of combustion byproducts through or around personal protective equipment (PPE) or from the cross-transfer of contaminants on PPE to the skin. Additionally, volatile contaminants can evaporate from PPE following a response and be inhaled by firefighters. Using polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs) as respective markers for non-volatile and volatile substances, we investigated the contamination of firefighters' turnout gear and skin following controlled residential fire responses. Participants were grouped into three crews of twelve firefighters. Each crew was deployed to a fire scenario (one per day, four total) and then paired up to complete six fireground job assignments. Wipe sampling of the exterior of the turnout gear was conducted pre- and post-fire. Wipe samples were also collected from a subset of the gear after field decontamination. VOCs off-gassing from gear were also measured pre-fire, post-fire, and post-decon. Wipe sampling of the firefighters' hands and neck was conducted pre- and post-fire. Additional wipes were collected after cleaning neck skin. PAH levels on turnout gear increased after each response and were greatest for gear worn by firefighters assigned to fire attack and to search and rescue activities. Field decontamination using dish soap, water, and scrubbing was able to reduce PAH contamination on turnout jackets by a median of 85%. Off-gassing VOC levels increased post-fire and then decreased 17-36 minutes later regardless of whether field decontamination was performed. Median post-fire PAH levels on the neck were near or below the limit of detection (< 24 micrograms per square meter [microg/m2]) for all positions. For firefighters assigned to attack, search, and outside ventilation, the 75th percentile values on the neck were 152, 71.7, and 39.3 microg/m2, respectively. Firefighters assigned to attack and search had higher post-fire median hand contamination (135 and 226 microg/m2, respectively) than other positions (< 10.5 microg/m2). Cleansing wipes were able to reduce PAH contamination on neck skin by a median of 54%. |
Evaluation and comparison of urinary metabolic biomarkers of exposure for the jet fuel JP-8
B'Hymer C , Krieg E Jr , Cheever KL , Toennis CA , Clark JC , Kesner JS , Gibson R , Butler MA . J Toxicol Environ Health A 2012 75 (11) 661-72 A study of workers exposed to jet fuel propellant 8 (JP-8) was conducted at U.S. Air Force bases and included the evaluation of three biomarkers of exposure: S-benzylmercapturic acid (BMA), S-phenylmercapturic acid (PMA), and (2-methoxyethoxy)acetic acid (MEAA). Postshift urine specimens were collected from various personnel categorized as high (n = 98), moderate (n = 38) and low (n = 61) JP-8 exposure based on work activities. BMA and PMA urinary levels were determined by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), and MEAA urinary levels were determined by gas chromatography-mass spectrometry (GC-MS). The numbers of samples determined as positive for the presence of the BMA biomarker (above the test method's limit of detection [LOD = 0.5 ng/ml]) were 96 (98.0%), 37 (97.4%), and 58 (95.1%) for the high, moderate, and low (control) exposure workgroup categories, respectively. The numbers of samples determined as positive for the presence of the PMA biomarker (LOD = 0.5 ng/ml) were 33 (33.7%), 9 (23.7%), and 12 (19.7%) for the high, moderate, and low exposure categories. The numbers of samples determined as positive for the presence of the MEAA biomarker (LOD = 0.1 mcg/ml) were 92 (93.4%), 13 (34.2%), and 2 (3.3%) for the high, moderate, and low exposure categories. Statistical analysis of the mean levels of the analytes demonstrated MEAA to be the most accurate or appropriate biomarker for JP-8 exposure using urinary concentrations either adjusted or not adjusted for creatinine; mean levels of BMA and PMA were not statistically significant between workgroup categories after adjusting for creatinine. |
Detection of DNA damage in workers exposed to JP-8 jet fuel
Krieg Jr EF , Mathias PI , Toennis CA , Clark JC , Marlow KL , B'Hymer C , Singh NP , Gibson RL , Butler MA . Mutat Res 2012 747 (2) 218-27 The genotoxicity of jet propulsion fuel 8 (JP-8) was assessed in the leukocytes of archived blood specimens from U.S. Air Force personnel using the comet assay. No differences in mean comet assay measurements were found between low, moderate, and high exposure groups before or after a 4hour work shift. Before the work shift, mean tail DNA and mean tail (Olive) moment increased as the concentration of benzene measured in end-exhaled breath increased, indicating that prior environmental or work-related exposures to benzene produced DNA damage. The number of cells with highly damaged DNA decreased as the pre-shift benzene concentration in breath increased. It is not clear why the decrease is occurring. Mean tail DNA and mean tail (Olive) moment decreased as the concentrations of benzene and naphthalene measured in breath immediately after the work shift increased. These inverse relationships may reflect a slower rate of absorption or a faster rate of expiration of benzene in the lung. The number of cells with highly damaged DNA increased as the concentration of urinary (2-methoxyethoxy)acetic acid (MEAA) increased. This relationship was not seen in urinary MEAA adjusted for creatinine. MEAA is a metabolite of the deicing agent 2-(2-methoxyethoxy)ethanol contained in JP-8. MEAA or a component of JP-8 correlated with MEAA may have a toxic effect on DNA. |
The bar sinister: does handlebar level damage the pelvic floor in female cyclists?
Partin SN , Connell KA , Schrader S , Lacombe J , Lowe B , Sweeney A , Reutman S , Wang A , Toennis C , Melman A , Mikhail M , Guess MK . J Sex Med 2012 9 (5) 1367-73 INTRODUCTION: Cycling is associated with genital neuropathies and erectile dysfunction in males. Women riders also have decreased genital sensation; however, sparse information exists addressing the effects of modifiable risks on neurological injuries in females. AIM: This study assesses the effects of bicycle setup and cyclists' attributes on GS and saddle pressures among female cyclists. METHODS: Previously, we compared genital sensation in competitive female cyclists (N = 48) to that of female runners (N = 22). The current study is a subanalysis of the 48 cyclists from the original study group. Nonpregnant, premenopausal women who rode at least 10 miles per week, 4 weeks per month were eligible for participation. MAIN OUTCOME MEASURES: Genital sensation was measured in microns using biosthesiometry measures of vibratory thresholds (VTs). Perineal and total saddle pressures were determined using a specialized pressure map and recorded in kilopascals (kPA). RESULTS: Handlebars positioned lower than the saddle correlated with increased perineum saddle pressures and decreased anterior vaginal and left labial genital sensation (P < 0.05, P < 0.02, P < 0.03, respectively). Low handlebars were not associated with total saddle pressures or altered genital sensation in other areas. After adjusting for age and saddle type, low handlebars were associated with a 3.47-kPA increase in mean perineum saddle pressures (P < 0.04) and a 0.86-micron increase in anterior vagina VT (P < 0.01). CONCLUSION: Handlebars positioned lower than the saddle were significantly associated with increased perineum saddle pressures and decreased genital sensation in female cyclists. Modifying bicycle setup may help alleviate neuropathies in females. Additional research is warranted to further assess the extent of the associations. |
Semi-quantitative analysis of influenza samples using the Luminex xTAG(®) respiratory viral panel kit.
Smith J , Sammons D , Toennis C , Butler MA , Blachere F , Beezhold D . Toxicol Mech Methods 2011 22 (3) 211-7 The Luminex xTAG(R) respiratory viral panel (RVP) kit simultaneously detects and identifies multiple respiratory viruses including several subtypes of influenza A using a multiplex nucleic acid amplification test assay platform. The emitted fluorescence signal from the RVP assay provides qualitative information on the presence of a particular viral species in respiratory specimens. However, a quantitative assessment is preferred when monitoring environmental samples for respiratory viruses. In this study, we explored the potential use of the RVP kit as a semi-quantitative screening assay for influenza virus detection. The concentration- response of the RVP assay was modeled using four-parameter logistic (4-PL) fits of mean fluorescence intensity (MFI) versus dilute ranges of the influenza A matrix gene, seasonal influenza vaccine, and 2009 H1N1 influenza vaccine. The goodness of fit of the 4-PL model was evaluated by comparing the copy number determined with the fitted model (observed copy number) with the copy number calculated from the dilution of the matrix DNA or vaccine (expected copy number). For the matrix DNA and 2009 H1N1 vaccine, the 4-PL model provided good fit for the influenza A RVP assay response over factors of 10(3) to 10(4). For seasonal influenza vaccine, the model provided good fit for RVP assay response to influenza A, influenza B, H1, and H3. |
The utility of naphthyl-keratin adducts as biomarkers for jet-fuel exposure
Kang-Sickel JC , Butler MA , Frame L , Serdar B , Chao YC , Egeghy P , Rappaport SM , Toennis CA , Li W , Borisova T , French JE , Nylander-French LA . Biomarkers 2011 16 (7) 590-9 We investigated the association between biomarkers of dermal exposure, naphthyl-keratin adducts (NKA), and urine naphthalene biomarker levels in 105 workers routinely exposed to jet-fuel. A moderate correlation was observed between NKA and urine naphthalene levels (p = 0.061). The NKA, post-exposure breath naphthalene, and male gender were associated with an increase, while CYP2E1*6 DD and GSTT1-plus (++/+-) genotypes were associated with a decrease in urine naphthalene level (p < 0.0001). The NKA show great promise as biomarkers for dermal exposure to naphthalene. Further studies are warranted to characterize the relationship between NKA, other exposure biomarkers, and/or biomarkers of biological effects due to naphthalene and/or PAH exposure. |
Women's bike seats: a pressing matter for competitive female cyclists
Guess MK , Partin SN , Schrader S , Lowe B , Lacombe J , Reutman S , Wang A , Toennis C , Melman A , Mikhail M , Connell KA . J Sex Med 2011 8 (11) 3144-53 INTRODUCTION: There are numerous genital complaints in women cyclists, including pain, numbness, and edema of pelvic floor structures. Debate ensues about the best saddle design for protection of the pelvic floor. AIM: To investigate the relationships between saddle design, seat pressures, and genital nerve function in female, competitive cyclists. METHODS: We previously compared genital sensation in healthy, premenopausal, competitive women bicyclists and runners. The 48 cyclists from our original study comprise the study group in this subanalysis. MAIN OUTCOME MEASURES: Main outcome measures were: (i) genital vibratory thresholds (VTs) determined using the Medoc Vibratory Sensation Analyzer 3000 and (ii) saddle pressures as determined using a specially designed map sensor. RESULTS: More than half of the participants (54.8%) used traditional saddles, and the remainder (45.2%) rode with cut-out saddles. On bivariate analysis, use of traditional saddles was associated with lower mean perineal saddle pressures (MPSP) than riding on cut-out saddles. Peak perineal saddle pressures (PPSP) were also lower; however, the difference did not reach statistical significance. Saddle design did not affect mean or peak total saddle pressures (MTSP, PTSP). Saddle width was significantly associated with PPSP, MTSP, and PTSP but not with MPSP. Women riding cut-out saddles had, on average, a 4 and 11 kPa increase in MPSP and PPSP, respectively, compared with women using traditional saddles (P = 0.008 and P = 0.010), after adjustment for other variables. Use of wider saddles was associated with lower PPSP and MTSP after adjustment. Although an inverse correlation was seen between saddle pressures and VTs on bivariate analysis, these differences were not significant after adjusting for age. CONCLUSION: Cut-out and narrower saddles negatively affect saddle pressures in female cyclists. Effects of saddle design on pudendal nerve sensory function were not apparent in this cross-sectional analysis. Longitudinal studies evaluating the long-term effects of saddle pressure on the integrity of the pudendal nerve, pelvic floor, and sexual function are warranted. |
(2-Methoxyethoxy)acetic acid: a urinary biomarker of exposure for jet fuel JP-8
B'Hymer C , Mathias P , Krieg E Jr , Cheever KL , Toennis CA , Clark JC , Kesner JS , Gibson RL , Butler MA . Int Arch Occup Environ Health 2011 85 (4) 413-20 PURPOSE: To demonstrate the utility of the urinary metabolite (2-methoxyethoxy)acetic acid (MEAA) as a biomarker of exposure. 2-(2-methoxyethoxy)ethanol [diethylene glycol monomethyl ether] is an anti-icing agent used in the formulation of JP-8, and it is added at a known uniform 0.1% (v/v) concentration to each batch lot. JP-8 is a kerosene-based fuel containing different compounds that vary in the content of every batch/lot of fuel; thus, MEAA has the potential to be a more specific and a consistent quantitative biomarker for JP-8 exposure. METHODS: MEAA was used to measure exposure of jet propulsion fuel 8 (JP-8) in United States Air Force (USAF) personnel working at six airbases within the United States. Post-shift urine specimens from various personnel including high (n = 98), moderate (n = 38), and low (n = 61) exposure workgroup categories were collected and analyzed by a gas chromatographic-mass spectrometric test method. The three exposure groups were evaluated for the number per group positive for MEAA, and a statistical analysis consisted of pair-wise t-tests for unequal variances was used to test for the differences in mean MEAA concentrations between the exposure groups. RESULTS: The number of samples detected as positive for MEAA exposure, that is, those above the test method's limit of detection (LOD = 0.1 mcg/ml), were 92 (93.9%), 13 (34.2%), and 2 (3.3%) for the high, moderate, and low exposure workgroup categories, respectively. The mean urinary MEAA level was significantly greater in the high exposure category (6.8 mcg/ml), compared to the moderate (0.42 mcg/ml) and the low (0.07 mcg/ml) exposure categories. The maximum concentration of urinary MEAA was 110 mcg/ml for the high exposure category, while 4.8 mcg/ml and 0.2 mcg/ml maximum levels were found in the moderate and low exposure categories, respectively. CONCLUSION: This study demonstrated that urinary MEAA can be used as an accurate biomarker of exposure for JP-8 workers and clearly distinguished the differences in JP-8 exposure by workgroup category. |
Evaluation of antineoplastic drug exposure of health care workers at three university-based U.S. cancer centers
Connor TH , DeBord DG , Pretty JR , Oliver MS , Roth TS , Lees PS , Krieg EF Jr , Rogers B , Escalante CP , Toennis CA , Clark JC , Johnson BC , McDiarmid MA . J Occup Environ Med 2010 52 (10) 1019-27 OBJECTIVE: This study evaluated health care worker exposure to antineoplastic drugs. METHODS: A cross-sectional study examined environmental samples from pharmacy and nursing areas. A 6-week diary documented tasks involving those drugs. Urine was analyzed for two specific drugs, and blood samples were analyzed by the comet assay. RESULTS: Sixty-eight exposed and 53 nonexposed workers were studied. Exposed workers recorded 10,000 drug-handling events during the 6-week period. Sixty percent of wipe samples were positive for at least one of the five drugs measured. Cyclophosphamide was most commonly detected, followed by 5-fluorouracil. Three of the 68 urine samples were positive for one drug. No genetic damage was detected in exposed workers using the comet assay. CONCLUSIONS: Despite following recommended safe-handling practices, workplace contamination with antineoplastic drugs in pharmacy and nursing areas continues at these locations. |
A pilot respiratory health assessment of nail technicians: symptoms, lung function, and airway inflammation
Reutman SR , Rohs AM , Clark JC , Johnson BC , Sammons DL , Toennis CA , Robertson SA , Mackenzie BA , Lockey JE . Am J Ind Med 2009 52 (11) 868-75 BACKGROUND: Recent surveys suggest nail technicians, particularly artificial nail applicators, have increased respiratory symptoms and asthma risk. METHODS: We examined lung function (n = 62) and a marker of airway inflammation, i.e., exhaled nitric oxide (ENO) (n = 43), in a subset of nail technician and control participants in a pilot health assessment. RESULTS: Bivariate analysis of technicians demonstrated that job latency was inversely correlated with FEV1 percent predicted (FEV1PP) (r = -0.34, P = 0.03) and FVCPP (r = -0.32, P = 0.05). Acrylic gel contact hours were inversely correlated with FEV1PP (r = -0.38, P = 0.02) and FVCPP (r = -0.47, P = 0.003). Current smoking was inversely and significantly (P ≤ 0.05) associated with ENO in bivariate analysis. Log 10 ENO levels were directly correlated with job latency (P = 0.012) and gel nail application (P = 0.026) in multivariable analyses. CONCLUSIONS: These positive pilot respiratory test results warrant additional future investigation. Am. J. Ind. Med. (c) 2009 Wiley-Liss, Inc. |
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