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Davidson A, Souza P. Relationships Between Auditory Processing and Cognitive Abilities in Adults: A Systematic Review. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2024; 67:296-345. [PMID: 38147487 DOI: 10.1044/2023_jslhr-22-00716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
PURPOSE The contributions from the central auditory and cognitive systems play a major role in communication. Understanding the relationship between auditory and cognitive abilities has implications for auditory rehabilitation for clinical patients. The purpose of this systematic review is to address the question, "In adults, what is the relationship between central auditory processing abilities and cognitive abilities?" METHOD Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to identify, screen, and determine eligibility for articles that addressed the research question of interest. Medical librarians and subject matter experts assisted in search strategy, keyword review, and structuring the systematic review process. To be included, articles needed to have an auditory measure (either behavioral or electrophysiologic), a cognitive measure that assessed individual ability, and the measures needed to be compared to one another. RESULTS Following two rounds of identification and screening, 126 articles were included for full analysis. Central auditory processing (CAP) measures were grouped into categories (behavioral: speech in noise, altered speech, temporal processing, binaural processing; electrophysiologic: mismatch negativity, P50, N200, P200, and P300). The most common CAP measures were sentence recognition in speech-shaped noise and the P300. Cognitive abilities were grouped into constructs, and the most common construct was working memory. The findings were mixed, encompassing both significant and nonsignificant relationships; therefore, the results do not conclusively establish a direct link between CAP and cognitive abilities. Nonetheless, several consistent relationships emerged across different domains. Distorted or noisy speech was related to working memory or processing speed. Auditory temporal order tasks showed significant relationships with working memory, fluid intelligence, or multidomain cognitive measures. For electrophysiology, relationships were observed between some cortical evoked potentials and working memory or executive/inhibitory processes. Significant results were consistent with the hypothesis that assessments of CAP and cognitive processing would be positively correlated. CONCLUSIONS Results from this systematic review summarize relationships between CAP and cognitive processing, but also underscore the complexity of these constructs, the importance of study design, and the need to select an appropriate measure. The relationship between auditory and cognitive abilities is complex but can provide informative context when creating clinical management plans. This review supports a need to develop guidelines and training for audiologists who wish to consider individual central auditory and cognitive abilities in patient care. SUPPLEMENTAL MATERIAL https://doi.org/10.23641/asha.24855174.
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Sterner TR, Covington TR, Mattie DR. Complex Mixtures: Array PBPK Modeling of Jet Fuel Components. TOXICS 2023; 11:187. [PMID: 36851061 PMCID: PMC9964161 DOI: 10.3390/toxics11020187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/12/2023] [Accepted: 02/14/2023] [Indexed: 06/18/2023]
Abstract
An array physiologically-based pharmacokinetic (PBPK) model represents a streamlined method to simultaneously quantify dosimetry of multiple compounds. To predict internal dosimetry of jet fuel components simultaneously, an array PBPK model was coded to simulate inhalation exposures to one or more selected compounds: toluene, ethylbenzene, xylenes, n-nonane, n-decane, and naphthalene. The model structure accounts for metabolism of compounds in the lung and liver, as well as kinetics of each compound in multiple tissues, including the cochlea and brain regions associated with auditory signaling (brainstem and temporal lobe). The model can accommodate either diffusion-limited or flow-limited kinetics (or a combination), allowing the same structure to be utilized for compounds with different characteristics. The resulting model satisfactorily simulated blood concentration and tissue dosimetry data from multiple published single chemical rat studies. The model was then utilized to predict tissue kinetics for the jet fuel hearing loss study (JTEH A, 25:1-14). The model was also used to predict rat kinetic comparisons between hypothetical exposures to JP-8 or a Virent Synthesized Aromatic Kerosene (SAK):JP-8 50:50 blend at the occupational exposure limit (200 mg/m3). The array model has proven useful for comparing potential tissue burdens resulting from complex mixture exposures.
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Affiliation(s)
- Teresa R. Sterner
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Wright-Patterson Air Force Base, Dayton, OH 45433, USA
- Air Force Research Laboratory, 711HPW/RHBAF, Wright-Patterson Air Force Base, Dayton, OH 45433, USA
| | - Tammie R. Covington
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Wright-Patterson Air Force Base, Dayton, OH 45433, USA
- Air Force Research Laboratory, 711HPW/RHBAF, Wright-Patterson Air Force Base, Dayton, OH 45433, USA
| | - David R. Mattie
- Air Force Research Laboratory, 711HPW/RHBAF, Wright-Patterson Air Force Base, Dayton, OH 45433, USA
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Guthrie OW. Abnormal neural adaptation consequent to combined exposure to jet fuel and noise. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2022; 85:671-684. [PMID: 35469543 DOI: 10.1080/15287394.2022.2069064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A fundamental property of first-order sensory neurons is the ability to alter their response properties as a function of change in the statistical parameters of an input signal. Such neural adaptation shapes the performance features of contiguous neural circuits that ultimately drive sensory discrimination. The current study focused on whether combined exposure to jet fuel and noise might alter the capacity of the auditory nerve to adapt to stimulus presentation speed. Young hooded Long-Evans 4-5 weeks old male rats were grouped and used in the current experiment. One group was exposed via inhalation to 1000 mg/m3 of jet propulsion fuel for 6 hr per day, 5 days per week for 4 weeks. Another group was exposed to a 5.5-11.3 kHz band-pass noise at 85 dB SPL for 6 hr per day, 5 days per week for 4 weeks. An additional group was simultaneously exposed to both jet fuel and noise. An age-matched group served as control and was not exposed to either jet fuel or noise. After experimental exposures, animals were given 4 weeks to recover and then assessed for neural adaptation. Both slow and fast rectangular voltage pulses were employed to elicit neuroelectric activity from the animals. Data demonstrated significant neural adaptation (1.46 μV shift) among controls, where neural activity decreased as the stimulus presentation speed rose from 10 to 100 per sec. This effect might also be observed in animals in the jet fuel treated and rats in the noise-exposed group. However, animals who were simultaneously exposed to both jet fuel and noise failed to exhibit neural adaptation. This abnormality appeared to be masked because independent slow and fast stimuli produced similar neural activity between controls and rats exposed to both jet fuel and noise. Therefore, neural adaptation assays may further be developed to unmask silent neurotoxicity consequent to physiochemical exposures.
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Affiliation(s)
- O'Neil W Guthrie
- Cell & Molecular Pathology Laboratory, Communication Sciences and Disorders, Northern Arizona University, Flagstaff, AZ, USA
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Guthrie OW, Wong BA, McInturf SM, Mattie DR. Degenerate brainstem circuitry after combined physiochemical exposure to jet fuel and noise. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2022; 85:175-183. [PMID: 34913848 DOI: 10.1080/15287394.2021.1980166] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Degenerate neural circuits exhibit "different" circuit properties yet produce similar circuit outcomes (many-to-one) which ensures circuit robustness and complexity. However, neuropathies may hijack degeneracy to yield robust and complex pathological circuits. The aim of the current study was to test the hypothesis that physiochemical exposure to combined jet fuel and noise might induce degeneracy in the brainstem. The auditory brainstem of pigmented rats was used as a model system. The animals were randomized into the following experimental groups: Fuel+Noise, fuel-only, noise-only, and control. Ascending volume conductance from various auditory brainstem regions were evaluated simultaneously with peripheral nervous system (PNS) input to brainstem circuitry. Data demonstrated normal PNS inputs for all groups. However, the Fuel+Noise exposure group produced different caudal brainstem circuit properties while rostral brainstem circuitry initiated outputs that were similar to that of control. This degenerative effect was specific to Fuel+Noise exposure, since neither noise-alone or fuel-alone produced the same result. Degeneracy in the auditory brainstem is consistent with perceptual abnormalities, such as poor speech discrimination (hear but not understand), tinnitus (ringing in the ear), hyperacusis (hypersensitivity to even low-level sound), and loudness intolerance. Therefore, a potential consequence of Fuel+Noise exposure among military and civilian populations may be evidenced as increased rates of super-threshold auditory perceptual abnormalities. This is particularly important because to date, the ototoxic profile of Fuel+Noise exposure has remained unresolved.
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Affiliation(s)
- O'neil W Guthrie
- Cell & Molecular Pathology Laboratory, Communication Sciences and Disorders, Northern Arizona University, Flagstaff, AZ, USA
| | - Brian A Wong
- Naval Medical Research Unit Dayton, Wright-Patterson Air Force Base, OH, USA
- Oak Ridge Institute for Science and Education (Orise), Oak Ridge, TN, USA
| | - Shawn M McInturf
- Naval Medical Research Unit Dayton, Wright-Patterson Air Force Base, OH, USA
| | - David R Mattie
- 711 Human Performance Wing, Wright-Patterson Air Force Base, OH, USA
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Dreisbach L, Murphy S, Arevalo R, Schlocker C, Miller T, Guthrie OW. Is jet fuel exposure associated with central auditory nervous system difficulties: An exploratory study in military personnel. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2022; 151:2027. [PMID: 35364904 DOI: 10.1121/10.0009845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
Central auditory nervous system dysfunction (CANSD) can manifest as hearing difficulty in the absence of audiometric abnormalities. Effects of noise or jet fuel exposure on the CANS are documented in animal models and humans. This study screened military personnel using the modified Amsterdam Inventory for Auditory Disability (mAIAD) to assess whether concurrent jet fuel and noise (JFN) exposures potentiate central auditory difficulties compared to noise only exposures. A total of 48 age- and sex-matched participants were recruited: 24 military bulk fuel specialists (JFN) and 24 military personnel without jet fuel exposure. All participants completed the mAIAD, the Noise Exposure Questionnaire, and basic audiological testing. Results revealed non-significant differences in pure-tone thresholds between groups, but the JFN group had higher noise exposures. Additionally, the JFN group revealed consistently lower mAIAD scores compared to the noise only group. Interestingly, a JFN stratified subgroup reporting more listening difficulty exhibited statistically significant lower mAIAD scores in the speech intelligibility in noise subdomain. These preliminary data suggest that jet fuel exposure may potentiate noise-induced CANSD, such as speech-in-noise difficulties. Such difficulties may be more prominent among specific military personnel with combined exposures. Hearing conservation programs could add CANSD screening by use of the mAIAD.
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Affiliation(s)
- Laura Dreisbach
- School of Speech, Language and Hearing Sciences, San Diego State University, 5500 Campanile Drive, San Diego, California 92182-1518, USA
| | - Sara Murphy
- Navy Medicine Readiness and Training Command San Diego (NMRTC SD), 34800 Bob Wilson Drive, San Diego, California 92134, USA
| | - Reginald Arevalo
- School of Speech, Language and Hearing Sciences, San Diego State University, 5500 Campanile Drive, San Diego, California 92182-1518, USA
| | - Caroline Schlocker
- Navy Medicine Readiness and Training Command San Diego (NMRTC SD), 34800 Bob Wilson Drive, San Diego, California 92134, USA
| | - Tanner Miller
- Navy Medicine Readiness and Training Command San Diego (NMRTC SD), 34800 Bob Wilson Drive, San Diego, California 92134, USA
| | - O'neil Winston Guthrie
- Department of Communication Sciences and Disorders, Northern Arizona University, 208 E. Pine Knoll Drive, Flagstaff, Arizona 86011, USA
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Guthrie OW, Bhatt IS. Nondeterministic nature of sensorineural outcomes following noise trauma. Biol Open 2021; 10:272549. [PMID: 34668520 PMCID: PMC8543023 DOI: 10.1242/bio.058696] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 09/08/2021] [Indexed: 11/20/2022] Open
Abstract
Over 1.1 billion individuals are at risk for noise induced hearing loss yet there is no accepted therapy. A long history of research has demonstrated that excessive noise exposure will kill outer hair cells (OHCs). Such observations have fueled the notion that dead OHCs underlie hearing loss. Therefore, previous and current therapeutic approaches are based on preventing the loss of OHCs. However, the relationship between OHC loss and hearing loss is at best a modest correlation. This suggests that in addition to the death of OHCs, other mechanisms may regulate the type and degree of hearing loss. In the current study, we tested the hypothesis that permanent noise-induced-hearing loss is consequent to additional mechanisms beyond the noise dose and the death of OHCs. Hooded male rats were randomly divided into noise and control groups. Morphological and physiological assessments were conducted on both groups. The combined results suggest that beyond OHC loss, the surviving cochlear elements shape sensorineural outcomes, which can be nondeterministic. These findings provide the basis for individualized ototherapeutics that manipulate surviving cellular elements in order to bias cochlear function towards normal hearing even in the presence of dead OHCs. Summary: The current findings provide the basis for individualized ototherapeutics that manipulate surviving cellular elements in order to bias cochlear function towards normal hearing even in the presence of dead cells.
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Affiliation(s)
- O'neil W Guthrie
- Department of Communication Sciences & Disorders, Northern Arizona University, Flagstaff, AZ 86011, USA.,Cell & Molecular Pathology Laboratory, Northern Arizona University, Flagstaff, AZ 86011, USA
| | - Ishan S Bhatt
- Audiogenomics Research Laboratory, Department of Communication Sciences and Disorders, The University of Iowa, Iowa City, IA 52242, USA
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Morata TC, Hungerford M, Konrad-Martin D. Potential Risks to Hearing Functions of Service Members From Exposure to Jet Fuels. Am J Audiol 2021; 30:922-927. [PMID: 34407375 DOI: 10.1044/2021_aja-20-00226] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Purpose Several military occupations, particularly those within the U.S. Air Force, require working with or around jet fuels. Jet fuels contain components that are known to affect central nervous function, yet effects of these fuels on auditory function, specifically auditory processing of sound, are not well understood at this time. Animal studies have demonstrated that exposure to jet fuels prior to noise exposure can exacerbate the noise exposure's effects, and service members exposed to jet fuels are at risk of noise exposure within their work environments. The purpose of this article was to give a brief synopsis of the evidence on the ototoxic effects due to jet fuel exposure to aid audiologists in their decision making when providing care for populations who are occupationally exposed to fuels or while during military service. Conclusions Exposure to jet fuels impacts central nervous function and, in combination with noise exposure, may have detrimental auditory effects that research has yet to fully explain. Additional longitudinal research is needed to explain the relationships, which have clinical implications for service members and others exposed to jet fuels. In the meantime, audiologists can gain useful information by screening for chemical exposures when obtaining patient case histories. If jet fuel exposure is suspected, the Lifetime Exposure to Noise and Solvents Questionnaire can be used to estimate a noise exposure ranking and identify other potentiating agents such as jet fuel and industrial chemicals. A history of jet fuel exposure should inform the selection of hearing tests in the audiometric evaluation and when devising the treatment plan.
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Affiliation(s)
- Thais C. Morata
- National Institute for Occupational Safety and Health, Cincinnati, OH
| | - Michelle Hungerford
- National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
| | - Dawn Konrad-Martin
- National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
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Lowe DA, Moore BCJ. Audiometric assessment of hearing loss sustained during military service. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:1030. [PMID: 34470327 DOI: 10.1121/10.0005846] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
An analysis is presented of the audiograms, obtained using Telephonics TDH39 headphones (Huntington, NY), of 80 men claiming compensation for noise-induced hearing loss (NIHL) sustained during military service. A comparison with an independent database of audiograms collected using other headphones suggested that no adjustment was needed to the hearing threshold levels (HTLs) at 6 kHz to allow for the use of TDH39 headphones. The method of Moore [(2020). J. Acoust. Soc. Am. 148, 884-894] for diagnosing military noise-induced hearing loss (M-NIHL) gave a positive diagnosis for 92.5% of right ears and 97.5% of left ears. The mean HTLs were maximal and similar at 4, 6, and 8 kHz but with considerable individual variability. A comparison with age-expected HTLs showed that M-NIHL was typically greatest at 3, 4, 6, or 8 kHz but with considerable individual variability. M-NIHL values were positive from 0.5 to 8 kHz. The HTLs were significantly higher for the left than for the right ears, but the asymmetry varied across individuals and could usually be ascribed to specific features of the noise exposure. The asymmetry existed over the range from 0.5 to 8 kHz, supporting the idea that M-NIHL occurs over a wide frequency range. Tinnitus was reported by 76 of the 80 men.
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Affiliation(s)
- David A Lowe
- ENT Department. James Cook University Hospital, Marton Road, Middlesbrough, Cleveland TS4 3BW, United Kingdom
| | - Brian C J Moore
- Cambridge Hearing Group, Department of Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, United Kingdom
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A Pilot Study of Airborne Hazards and Other Toxic Exposures in Iraq War Veterans. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17093299. [PMID: 32397395 PMCID: PMC7246947 DOI: 10.3390/ijerph17093299] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 05/07/2020] [Indexed: 01/10/2023]
Abstract
During their deployment to Iraq in support of Operation Iraqi Freedom (OIF), many Veterans were exposed to a wide array of toxic substances and psychologic stressors, most notably airborne/environmental pollutants from open burn pits. Service members do not deploy whilst unhealthy, but often they return with a multitude of acute and chronic symptoms, some of which only begin to manifest years after their deployment. Our findings, while preliminary in nature, suggest that Iraq War Veterans who participated in our survey reported a decrease in overall physical fitness and increased respiratory clinical symptoms compared with pre-deployment periods. The objective of this report is to provide information that will benefit how combat Veterans are cared for post-deployment. Strategies for a wider and more comprehensive assessment and medical screening process post-deployment are recommended.
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Tepe V, Papesh M, Russell S, Lewis MS, Pryor N, Guillory L. Acquired Central Auditory Processing Disorder in Service Members and Veterans. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2020; 63:834-857. [PMID: 32163310 DOI: 10.1044/2019_jslhr-19-00293] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Purpose A growing body of evidence suggests that military service members and military veterans are at risk for deficits in central auditory processing. Risk factors include exposure to blast, neurotrauma, hazardous noise, and ototoxicants. We overview these risk factors and comorbidities, address implications for clinical assessment and care of central auditory processing deficits in service members and veterans, and specify knowledge gaps that warrant research. Method We reviewed the literature to identify studies of risk factors, assessment, and care of central auditory processing deficits in service members and veterans. We also assessed the current state of the science for knowledge gaps that warrant additional study. This literature review describes key findings relating to military risk factors and clinical considerations for the assessment and care of those exposed. Conclusions Central auditory processing deficits are associated with exposure to known military risk factors. Research is needed to characterize mechanisms, sources of variance, and differential diagnosis in this population. Existing best practices do not explicitly consider confounds faced by military personnel. Assessment and rehabilitation strategies that account for these challenges are needed. Finally, investment is critical to ensure that Veterans Affairs and Department of Defense clinical staff are informed, trained, and equipped to implement effective patient care.
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Affiliation(s)
- Victoria Tepe
- Department of Defense Hearing Center of Excellence, JBSA Lackland, TX
- The Geneva Foundation, Tacoma, WA
| | - Melissa Papesh
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
- Department of Otolaryngology-Head & Neck Surgery, Oregon Health & Science University, Portland
| | - Shoshannah Russell
- Walter Reed National Military Medical Center, Bethesda, MD
- Henry Jackson Foundation, Bethesda, MD
| | - M Samantha Lewis
- VA RR&D National Center for Rehabilitative Auditory Research, VA Portland Health Care System, OR
- Department of Otolaryngology-Head & Neck Surgery, Oregon Health & Science University, Portland
- School of Audiology, Pacific University, Hillsboro, OR
| | - Nina Pryor
- Department of Defense Hearing Center of Excellence, JBSA Lackland, TX
- Air Force Research Laboratory, Wright-Patterson Air Force Base, OH
| | - Lisa Guillory
- Harry S. Truman Memorial Veterans' Hospital, Columbia, MO
- Department of Otolaryngology-Head and Neck Surgery, School of Medicine, University of Missouri, Columbia
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Fuente A, Hickson L, Morata TC, Williams W, Khan A, Fuentes-Lopez E. Jet fuel exposure and auditory outcomes in Australian air force personnel. BMC Public Health 2019; 19:675. [PMID: 31151392 PMCID: PMC6544957 DOI: 10.1186/s12889-019-7038-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 05/23/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Animal data suggest that jet fuels such as JP-8 are associated with hearing deficits when combined with noise and that the effect is more pronounced than with noise exposure alone. Some studies suggest peripheral dysfunction while others suggest central auditory dysfunction. Human data are limited in this regard. The aim of this study was to investigate the possible chronic adverse effects of JP-8 combined with noise exposure on the peripheral and central auditory systems in humans. METHODS Fifty-seven participants who were current personnel from the Royal Australian Air Force were selected. Based on their levels of exposure to jet fuels, participants were divided into three exposure groups (low, moderate, high). Groups were also categorised based on their noise exposure levels (low, moderate, high). All participants were evaluated by tympanometry, pure-tone audiometry (1-12 kHz), distortion product otoacoustic emissions (DPOAEs), auditory brainstem response (ABR), words-in-noise, compressed speech, dichotic digit test, pitch pattern sequence test, duration pattern sequence test and adaptive test of temporal resolution. All auditory tests were carried out after the participants were away from the Air Force base for a minimum of two weeks, thus two weeks without jet fuel and noise exposure. RESULTS Jet fuel exposure was significantly associated with hearing thresholds at 4 and 8 kHz; average hearing thresholds across frequencies in the better ear; DPOAEs at 2.8, 4 and 6 kHz; ABR wave V latency in the right ear; compressed speech and words-in-noise. Further analyses revealed that participants with low exposure level to jet fuels showed significantly better results for the aforementioned procedures than participants with moderate and high exposure levels. All results were controlled for the covariates of age and noise exposure levels. CONCLUSIONS The results suggest that jet fuel exposure, when combined with noise exposure, has an adverse effect on audibility in humans. Taking all the test results into consideration, jet fuel exposure combined with noise exposure specifically seems to affect the peripheral hearing system in humans.
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Affiliation(s)
- Adrian Fuente
- School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia. .,Centre de recherche de l'Institut universitaire de gériatrie de Montréal, Montreal, Quebec, Canada.
| | - Louise Hickson
- School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia
| | - Thais C Morata
- National Institute for Occupational Safety and Health, Cincinnati, OH, USA
| | | | - Asaduzzaman Khan
- School of Health and Rehabilitation Sciences, The University of Queensland, Brisbane, Australia
| | - Eduardo Fuentes-Lopez
- Carrera de Fonoaudiología, Departamento de Ciencias de la Salud, Pontificia Universidad Católica de Chile, Santiago, Chile
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Abstract
PURPOSE Noise levels remain high in clinical settings, which may result in stress and sleep disruption, and can lead to immunosuppression, delayed healing, confusion, disorientation, delusions, and increased length of hospital stay. The purpose of this quality improvement project was to assess effects of a multidisciplinary noise reduction program on a pediatric unit in an acute care hospital in a developing country. METHODS A quality improvement project was carried out over 15 months in a pediatric unit. A three-phase study was conducted where the first phase included obtaining patient satisfaction ratings and recording sound levels, the second phase included implementing a noise reduction program and designing a noise detector machine, and the third phase included obtaining patient satisfaction data and recording noise levels over a 1-year period. RESULTS There was a significant decrease in noise of 8 A-weighted decibels when comparing the values before and after implementing the quality improvement project at t = 6.44, p < 0.000. There was no significant difference in patient satisfaction ratings. CLINICAL IMPLICATIONS Noise in the pediatric unit exceeded recommended guidelines; however, decreasing the levels was possible and sustainable, which can improve the psychological and physiological wellbeing of hospitalized children.
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Fife TD, Robb MJA, Steenerson KK, Saha KC. Bilateral Vestibular Dysfunction Associated With Chronic Exposure to Military Jet Propellant Type-Eight Jet Fuel. Front Neurol 2018; 9:351. [PMID: 29867750 PMCID: PMC5964212 DOI: 10.3389/fneur.2018.00351] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 05/01/2018] [Indexed: 12/19/2022] Open
Abstract
We describe three patients diagnosed with bilateral vestibular dysfunction associated with the jet propellant type-eight (JP-8) fuel exposure. Chronic exposure to aromatic and aliphatic hydrocarbons, which are the main constituents of JP-8 military aircraft jet fuel, occurred over 3–5 years’ duration while working on or near the flight line. Exposure to toxic hydrocarbons was substantiated by the presence of JP-8 metabolite n-hexane in the blood of one of the cases. The presenting symptoms were dizziness, headache, fatigue, and imbalance. Rotational chair testing confirmed bilateral vestibular dysfunction in all the three patients. Vestibular function improved over time once the exposure was removed. Bilateral vestibular dysfunction has been associated with hydrocarbon exposure in humans, but only recently has emphasis been placed specifically on the detrimental effects of JP-8 jet fuel and its numerous hydrocarbon constituents. Data are limited on the mechanism of JP-8-induced vestibular dysfunction or ototoxicity. Early recognition of JP-8 toxicity risk, cessation of exposure, and customized vestibular therapy offer the best chance for improved balance. Bilateral vestibular impairment is under-recognized in those chronically exposed to all forms of jet fuel.
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Affiliation(s)
- Terry D Fife
- Barrow Neurological Institute, Phoenix, AZ, United States
| | | | | | - Kamala C Saha
- Barrow Neurological Institute, Phoenix, AZ, United States
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Rohan JG, McInturf SM, Miklasevich MK, Gut CP, Grimm MD, Reboulet JE, Howard WR, Mumy KL. Comparative electrophysiological evaluation of hippocampal function following repeated inhalation exposures to JP-8, Jet A, JP-5, and the synthetic Fischer Tropsch fuel. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2018; 81:314-332. [PMID: 29498600 DOI: 10.1080/15287394.2018.1437097] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 01/12/2018] [Accepted: 02/01/2018] [Indexed: 06/08/2023]
Abstract
Exposure to fuels continues to be a concern in both military and general populations. The aim of this study was to examine effects of in vivo rat repeated exposures to different types of jet fuel utilizing microelectrode arrays for comparative electrophysiological (EP) measurements in hippocampal slices. Animals were exposed to increasing concentrations of four jet fuels, Jet Propellant (JP)-8, Jet A, JP-5, or synthetic Fischer Tropsch (FT) fuel via whole-body inhalation for 20 d (6 hr/d, 5 d/week for 28 d) and synaptic transmission as well as behavioral performance were assessed. Our behavioral studies indicated no significant changes in behavioral performance in animals exposed to JP-8, Jet A, or JP-5. A significant deviation in learning pattern during the Morris water maze task was observed in rats exposed to the highest concentration of FT (2000 mg/m3). There were also significant differences in the EP profile of hippocampal neurons from animals exposed to JP-8, Jet A, JP-5, or FT compared to control air. However, these differences were not consistent across fuels or dose dependent. As expected, patterns of EP alterations in brain slices from JP-8 and Jet A exposures were more similar compared to those from JP-5 and FT. Further longitudinal investigations are needed to determine if these EP effects are transient or persistent. Such studies may dictate if and how one may use EP measurements to indicate potential susceptibility to neurological impairments, particularly those that result from inhalation exposure to chemicals or mixtures.
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Affiliation(s)
- Joyce G Rohan
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
- b Oak Ridge Institute for Science and Education , Oak Ridge , TN
| | - Shawn M McInturf
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
| | - Molly K Miklasevich
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
- c CAMRIS International , Bethesda , MD
| | - Chester P Gut
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
- c CAMRIS International , Bethesda , MD
| | - Michael D Grimm
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
- c CAMRIS International , Bethesda , MD
| | - James E Reboulet
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
- c CAMRIS International , Bethesda , MD
| | - William R Howard
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
| | - Karen L Mumy
- a Naval Medical Research Unit Dayton (NAMRU-D) , Wright-Patterson Air Force Base , Dayton , OH
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15
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Mattie DR, Sterner TR, Reddy G, Steup DR, Zeiger E, Wagner DJ, Kurtz K, Daughtrey WC, Wong BA, Dodd DE, Edwards JT, Hinz JP. Toxicity and occupational exposure assessment for Fischer-Tropsch synthetic paraffinic kerosene. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2018; 81:774-791. [PMID: 29985787 DOI: 10.1080/15287394.2018.1490675] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 06/14/2018] [Accepted: 06/15/2018] [Indexed: 05/20/2023]
Abstract
Fischer-Tropsch (FT) Synthetic Paraffinic Kerosene (SPK) jet fuel is a synthetic organic mixture intended to augment petroleum-derived JP-8 jet fuel use by the U.S. armed forces. The FT SPK testing program goal was to develop a comparative toxicity database with petroleum-derived jet fuels that may be used to calculate an occupational exposure limit (OEL). Toxicity investigations included the dermal irritation test (FT vs. JP-8 vs. 50:50 blend), 2 in vitro genotoxicity tests, acute inhalation study, short-term (2-week) inhalation range finder study with measurement of bone marrow micronuclei, 90-day inhalation toxicity, and sensory irritation assay. Dermal irritation was slight to moderate. All genotoxicity studies were negative. An acute inhalation study with F344 rats exposed at 2000 mg/m3 for 4 hr resulted in no abnormal clinical observations. Based on a 2-week range-finder, F344 rats were exposed for 6 hr per day, 5 days per week, for 90 days to an aerosol-vapor mixture of FT SPK jet fuel (0, 200, 700 or 2000 mg/m3). Effects on the nasal cavities were minimal (700 mg/m3) to mild (2000 mg/m3); only high exposure produced multifocal inflammatory cell infiltration in rat lungs (both genders). The RD50 (50% respiratory rate depression) value for the sensory irritation assay, calculated to be 10,939 mg/m3, indicated the FT SPK fuel is less irritating than JP-8. Based upon the proposed use as a 50:50 blend with JP-8, a FT SPK jet fuel OEL is recommended at 200 mg/m3 vapor and 5 mg/m3 aerosol, in concurrence with the current JP-8 OEL.
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Affiliation(s)
- David R Mattie
- a Molecular Mechanisms Branch, Human Centered ISR Division, Human Effectiveness Directorate (711 HPW/RHXJ), Air Force Research Laboratory , Wright-Patterson AFB OH
| | - Teresa R Sterner
- b Henry M. Jackson Foundation for the Advancement of Military Medicine (HJF) , Wright-Patterson AFB , OH , U.S.A
| | - Gunda Reddy
- c U.S. Army Public Health Center , Aberdeen Proving Grounds , MD , U.S.A
| | | | - Errol Zeiger
- e Errol Zeiger Consulting , Chapel Hill , NC , U.S.A
| | - Dean J Wagner
- f Naval Medical Research Unit Dayton (NAMRU-D), Wright-Patterson AFB OH
| | - Katherine Kurtz
- g Navy and Marine Corps Public Health Center , Portsmouth , VA , U.S.A
| | | | - Brian A Wong
- f Naval Medical Research Unit Dayton (NAMRU-D), Wright-Patterson AFB OH
| | - Darol E Dodd
- i Charles River Laboratories , Spencerville , OH , U.S.A
| | - James T Edwards
- j Fuels and Energy Branch, Air Force Research Laboratory , Wright-Patterson AFB , OH , U.S.A
| | - John P Hinz
- k U.S. Air Force School of Aerospace Medicine , Wright-Patterson AFB , OH , U.S.A
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16
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Carlson K, Neitzel RL. Hearing loss, lead (Pb) exposure, and noise: a sound approach to ototoxicity exploration. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2018; 21:335-355. [PMID: 30663930 PMCID: PMC9903337 DOI: 10.1080/10937404.2018.1562391] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
To determine the state of the research on ototoxic properties of Pb, evaluate possible synergistic effects with concurrent noise exposure, and identify opportunities to improve future research, we performed a review of the peer-reviewed literature to identify studies examining auditory damage due to Pb over the past 50 years. Thirty-eight studies (14 animal and 24 human) were reviewed. Of these, 24 suggested potential ototoxicity due to Pb exposure, while 14 found no evidence of ototoxicity. More animal studies are needed, especially those investigating Pb exposure levels that are occupationally and environmentally relevant to humans. Further investigations into potential interactions of Pb in the auditory system with other hazards and compounds that elicit ototoxicity are also needed in animal models. To better assess the effects of Pb exposure on the human auditory system and the possibility of a synergism with noise, future epidemiological studies need to carefully consider and address four main areas of uncertainty: (1) hearing examination and quantification of hearing loss, (2) Pb exposure evaluation, (3) noise exposure evaluation, and (4) the personal characteristics of those exposed. Two potentially confounding factors, protective factors and mixtures of ototoxicants, also warrant further exploration.
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Affiliation(s)
- Krystin Carlson
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, USA
| | - Richard L Neitzel
- Department of Environmental Health Sciences, University of Michigan, Ann Arbor, USA
- Corresponding Author -- Richard L. Neitzel: , University of Michigan, Department of Environmental Health Sciences, 1415 Washington Heights 6611 SPH I, Ann Arbor, MI 48109, 734-763-2870
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17
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Guthrie OW. Functional consequences of inducible genetic elements from the p53 SOS response in a mammalian organ system. Exp Cell Res 2017; 359:50-61. [DOI: 10.1016/j.yexcr.2017.08.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2017] [Revised: 08/02/2017] [Accepted: 08/05/2017] [Indexed: 10/19/2022]
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18
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Background Noise Contributes to Organic Solvent Induced Brain Dysfunction. Neural Plast 2016; 2016:8742725. [PMID: 26885406 PMCID: PMC4739468 DOI: 10.1155/2016/8742725] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 12/22/2015] [Indexed: 12/13/2022] Open
Abstract
Occupational exposure to complex blends of organic solvents is believed to alter brain functions among workers. However, work environments that contain organic solvents are also polluted with background noise which raises the issue of whether or not the noise contributed to brain alterations. The purpose of the current study was to determine whether or not repeated exposure to low intensity noise with and without exposure to a complex blend of organic solvents would alter brain activity. Female Fischer344 rats served as subjects in these experiments. Asynchronous volume conductance between the midbrain and cortex was evaluated with a slow vertex recording technique. Subtoxic solvent exposure, by itself, had no statistically significant effects. However, background noise significantly suppressed brain activity and this suppression was exacerbated with solvent exposure. Furthermore, combined exposure produced significantly slow neurotransmission. These abnormal neurophysiologic findings occurred in the absence of hearing loss and detectable damage to sensory cells. The observations from the current experiment raise concern for all occupations where workers are repeatedly exposed to background noise or noise combined with organic solvents. Noise levels and solvent concentrations that are currently considered safe may not actually be safe and existing safety regulations have failed to recognize the neurotoxic potential of combined exposures.
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19
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Guthrie OW, Wong BA, McInturf SM, Reboulet JE, Ortiz PA, Mattie DR. Inhalation of Hydrocarbon Jet Fuel Suppress Central Auditory Nervous System Function. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2015; 78:1154-1169. [PMID: 26408153 DOI: 10.1080/15287394.2015.1070389] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
More than 800 million L/d of hydrocarbon fuels is used to power cars, boats, and jet airplanes. The weekly consumption of these fuels necessarily puts the public at risk for repeated inhalation exposure. Recent studies showed that exposure to hydrocarbon jet fuel produces lethality in presynaptic sensory cells, leading to hearing loss, especially in the presence of noise. However, the effects of hydrocarbon jet fuel on the central auditory nervous system (CANS) have not received much attention. It is important to investigate the effects of hydrocarbons on the CANS in order to complete current knowledge regarding the ototoxic profile of such exposures. The objective of the current study was to determine whether inhalation exposure to hydrocarbon jet fuel might affect the functions of the CANS. Male Fischer 344 rats were randomly divided into four groups (control, noise, fuel, and fuel + noise). The structural and functional integrity of presynaptic sensory cells was determined in each group. Neurotransmission in both peripheral and central auditory pathways was simultaneously evaluated in order to identify and differentiate between peripheral and central dysfunctions. There were no detectable effects on pre- and postsynaptic peripheral functions. However, the responsiveness of the brain was significantly depressed and neural transmission time was markedly delayed. The development of CANS dysfunctions in the general public and the military due to cumulative exposure to hydrocarbon fuels may represent a significant but currently unrecognized public health issue.
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Affiliation(s)
- O'neil W Guthrie
- a Cell & Molecular Pathology Laboratory, Department of Communication Sciences and Disorders , Northern Arizona University , Flagstaff , Arizona , USA
- b Research Service, Loma Linda Veterans Affairs Medical Center , Loma Linda , California , USA
- c Department of Otolaryngology and Head & Neck Surgery , School of Medicine, Loma Linda University Medical Center , Loma Linda , California , USA
| | - Brian A Wong
- d Naval Medical Research Unit-Dayton , Wright-Patterson Air Force Base , Ohio , USA
| | - Shawn M McInturf
- d Naval Medical Research Unit-Dayton , Wright-Patterson Air Force Base , Ohio , USA
| | - James E Reboulet
- d Naval Medical Research Unit-Dayton , Wright-Patterson Air Force Base , Ohio , USA
| | - Pedro A Ortiz
- d Naval Medical Research Unit-Dayton , Wright-Patterson Air Force Base , Ohio , USA
| | - David R Mattie
- e Molecular Bioeffects Branch, Bioeffects Division, Human Effectiveness Directorate , Air Force Research Laboratory, Wright Patterson Air Force Base , Ohio , USA
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20
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Maiyoh GK, Njoroge RW, Tuei VC. Effects and mechanisms of kerosene use-related toxicity. ENVIRONMENTAL TOXICOLOGY AND PHARMACOLOGY 2015; 40:57-70. [PMID: 26063683 DOI: 10.1016/j.etap.2015.05.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2015] [Revised: 05/11/2015] [Accepted: 05/16/2015] [Indexed: 06/04/2023]
Abstract
Kerosene is a heterogeneous hydrocarbon substance that continues to find many uses worldwide due to its economic viability and ease of availability. In spite of kerosene's many uses, it is known to cause harm to various body organs and systems. Major affected body organs/systems are the pulmonary system, central nervous system, cardiovascular system, the skin, immune system and liver. This review discusses the various kerosene-mediated adverse health effects and possible mechanisms by which kerosene is likely to inflict such effects. These mechanisms are quite varied and include induction of inflammation, loss of effectiveness of pulmonary surfactants, hypoxia, production of highly reactive oxidative metabolites, extraction of endogenous epidermal and membrane lipids, necrosis, hormonal and enzymatic levels changes, and immunosuppression. Understanding of the above will allow for proper relevant policy formulation and targeted kerosene-mediated morbidity and mortality preventive and management initiatives.
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Affiliation(s)
- Geoffrey K Maiyoh
- Department of Medical Biochemistry, School of Medicine, Moi University, P.O. Box 4606-30100, Eldoret, Kenya.
| | - Rachel W Njoroge
- Department of Chemistry and Biochemistry, School of Science, University of Eldoret, P.O. Box 1125-30100, Eldoret, Kenya.
| | - Vivian C Tuei
- Department of Chemistry and Biochemistry, School of Science, University of Eldoret, P.O. Box 1125-30100, Eldoret, Kenya.
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21
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Sweeney LM, Kester JE, Kirman CR, Gentry PR, Banton MI, Bus JS, Gargas ML. Risk assessments for chronic exposure of children and prospective parents to ethylbenzene (CAS No. 100-41-4). Crit Rev Toxicol 2015; 45:662-726. [PMID: 25997510 DOI: 10.3109/10408444.2015.1046157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Potential chronic health risks for children and prospective parents exposed to ethylbenzene were evaluated in response to the Voluntary Children's Chemical Evaluation Program. Ethylbenzene exposure was found to be predominately via inhalation with recent data demonstrating continuing decreases in releases and both outdoor and indoor concentrations over the past several decades. The proportion of ethylbenzene in ambient air that is attributable to the ethylbenzene/styrene chain of commerce appears to be relatively very small, less than 0.1% based on recent relative emission estimates. Toxicity reference values were derived from the available data, with physiologically based pharmacokinetic models and benchmark dose methods used to assess dose-response relationships. An inhalation non-cancer reference concentration or RfC of 0.3 parts per million (ppm) was derived based on ototoxicity. Similarly, an oral non-cancer reference dose or RfD of 0.5 mg/kg body weight/day was derived based on liver effects. For the cancer assessment, emphasis was placed upon mode of action information. Three of four rodent tumor types were determined not to be relevant to human health. A cancer reference value of 0.48 ppm was derived based on mouse lung tumors. The risk characterization for ethylbenzene indicated that even the most highly exposed children and prospective parents are not at risk for non-cancer or cancer effects of ethylbenzene.
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22
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Carvalhais C, Santos J, da Silva MV, Xavier A. Is There Sufficient Training of Health Care Staff on Noise Reduction in Neonatal Intensive Care Units? a Pilot Study From Neonoise Project. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2015; 78:897-903. [PMID: 26167755 DOI: 10.1080/15287394.2015.1051204] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Evidence indicates that exposure to high levels of noise adversely affects human health, and these effects are dependent upon various factors. In hospitals, there are many sources of noise, and high levels exert an impact on patients and staff, increasing both recovery time and stress, respectively. The goal of this pilot study was to develop, implement, and evaluate the effectiveness of a training program (TP) on noise reduction in a neonatal intensive care unit (NICU) by comparing the noise levels before and after the implementation of the program. In total, 79 health professionals participated in the study. The measurements of sound pressure levels took into account the layout of the unit and locations of the main sources of noise. General results indicated that LAeq levels before implementation of the training program were often excessive, ranging from 48.7 ± 2.94 dBA to 71.7 ± 4.74 dBA, exceeding international guidelines. Similarly, following implementation of the training program, noise levels remained unchanged (54.5 ± 0.49 dBA to 63.9 ± 4.37 dBA), despite a decrease in some locations. There was no significant difference before and after the implementation of TP. However, a significant difference was found for Lp,Cpeak, before and after training staff, suggesting greater care by health care professionals performing their tasks. Even recognizing that a TP is quite important to change behaviors, this needs to be considered in a broader context to effectively control noise in the NICU.
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Affiliation(s)
- Carlos Carvalhais
- a Environmental Health Department and Research Centre on Health and Environment (CISA) , School of Allied Health Technologies of Polytechnic Institute of Porto (ESTSP.IPP) , Vila Nova de Gaia , Portugal
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23
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Rodrigues MA, Amorim M, Silva MV, Neves P, Sousa A, Inácio O. Sound Levels and Risk Perceptions of Music Students During Classes. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART A 2015; 78:825-839. [PMID: 26167749 DOI: 10.1080/15287394.2015.1051174] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
It is well recognized that professional musicians are at risk of hearing damage due to the exposure to high sound pressure levels during music playing. However, it is important to recognize that the musicians' exposure may start early in the course of their training as students in the classroom and at home. Studies regarding sound exposure of music students and their hearing disorders are scarce and do not take into account important influencing variables. Therefore, this study aimed to describe sound level exposures of music students at different music styles, classes, and according to the instrument played. Further, this investigation attempted to analyze the perceptions of students in relation to exposure to loud music and consequent health risks, as well as to characterize preventive behaviors. The results showed that music students are exposed to high sound levels in the course of their academic activity. This exposure is potentiated by practice outside the school and other external activities. Differences were found between music style, instruments, and classes. Tinnitus, hyperacusis, diplacusis, and sound distortion were reported by the students. However, students were not entirely aware of the health risks related to exposure to high sound pressure levels. These findings reflect the importance of starting intervention in relation to noise risk reduction at an early stage, when musicians are commencing their activity as students.
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Affiliation(s)
- Matilde A Rodrigues
- a Department of Environmental Health , Research Centre on Health and Environment, Allied Health Sciences School of Polytechnic Institute of Porto , Vila Nova de Gaia , Portugal
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