Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Noise, Occupational”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1998

Auditory dysfunction in occupational noise exposed workers.

Occupational noise-induced hearing loss (NIHL) is well known to be an epidemiologically relevant problem. The subjects affected with NIHL show alteration of hearing thresholds as well as a worsening of the cochlear analysis functions and, usually, an impaired speech discrimination in presence of background noise. The study has evaluated the relationships between hearing threshold and equivalent exposure lever per day (Lepd), age and working seniority in a homogeneous sample of occupationally noise exposed workers. Three subgroups were also selected to study the most important cochlear functions as well as nerve and central functions. The first subgroup (Nn) contained normal hearing workers exposed to non-hazardous noise, while the second (Bn) contained workers exposed to high level continuous noise during their work day without clinical evidence of NIHL. The third subgroup (Bd) included subjects affected with the typical 4 kHz notch exposed to the same noise conditions than subgroup Bn. The results show that the hearing impaired subjects have the worst overall cochlear performance; however also the normal hearing workers exposed to hazardous noise have worse performance than subgroup Nn, relatively to high frequency thresholds, frequency resolution, TEOAEs, DPOAEs, stapedial acoustic reflex dynamic parameters. The results suggest that these measures could be used in the monitoring of the NIHL as indicators of subtle alterations of the hearing function.

Acoustic Impedance Tests↗
PubMedDate not supplied

Exposure to occupational noise: otoacoustic emissions test alterations.

UNLABELLED: Exposure to occupational noise may cause injuries to the inner ear, and the distortion product otoacoustic emissions (DPOAE) may identify initial auditory alterations, thus assisting NIHL early diagnosis. AIM: The goal of this study was to evaluate DPOAE as a method to diagnose early physiopathological alterations caused by occupational noise exposure. STUDY DESIGN: Transversal. METHODS: 74 workers of the University of São Paulo, in the capital city of the State, participated in this investigation. They were divided in two age-matched groups and with tonal audiometric values within the acceptable limits: 37 were exposed to occupational noise and 37 were not exposed. RESULTS: Risk estimates (Odds Ratio) of absent DPOAE was 12 fold higher for the group exposed to occupational noise (CI 95% 3.1-45.9), in the frequencies of 3. 4 and 6 kHz. CONCLUSION: DPOAE may be useful in the identification of physiopathological hearing alterations caused by exposure to occupational noise, even in individuals with tonal audiometric responses within acceptable limits.

Acoustic Stimulation↗
PubMed1990

[Rational nutrition under the effect of occupational noise on the body].

Basing on medical literature data, the contributors deal with the positive role of diet therapy, including specific food substances and their complexes, in case with patients from noise-affected occupations. Prophylactic diet patterns are proposed specifically intended for workers engaged in intensive industrial noise professions.

Amino Acids↗
PubMed1992

Is NIDDM a risk factor for noise-induced hearing loss in an occupationally noise exposed cohort?

Little is known about what factors, other than chronic exposure to noise, predispose individuals to noise-induced hearing loss (NIHL). The current retrospective study was designed to identify risk factors for NIHL in a population of 229 men [age 55-68 (mean = 63 years)] employed at a metal assembly plant. All men had been chronically occupationally noise-exposed for approximately 30 years (> or = 89 dBA) with an average Ea noise emission level) of 104.5. The clinical examination included a pure-tone threshold audiometric evaluation, discrimination of speech in background noise [W-22 Max (> 60% indicating better hearing)], blood pressure measurement, evaluation of lifestyle (alcohol consumption, cigarette smoking, noisy hobbies) and occupational and military history. Severe NIHL was defined as > or = 65 db loss at 3, 4 or 6 kHz in at least one ear +/- 20 db threshold in the contralateral ear. History of non-insulin dependent diabetes mellitus (NIDDM) was reported by 16.4% of the 146 men with severe NIHL compared to 4.8% of the 83 men without severe NIHL (odds ratio = 3.9, C.I. 1.2-11.9, P = 0.05). Simultaneous evaluation of several potential risk factors using a multiple logistic regression indicates that the significant predictors of severe NIHL were diabetes (P < 0.05), Ea (P < 0.05) and age (P < 0.05). These results suggest that a person with NIDDM who is also occupationally noise-exposed is more likely to develop severe NIHL than those without NIDDM. Longitudinal studies are necessary to confirm the temporal relationship between NIDDM and NIHL and to determine the exact mechanisms that are involved with this increased risk of hearing loss.

Age Factors↗
PubMed2003

Effects of occupational noise exposure on blood pressure.

We measured 24-hour ambulatory blood pressure and 16-hour noise exposure continuously for 20 automobile workers, and used linear mixed-effects regression models to estimate transient and sustained effects of noise exposure on blood pressure. The occupational noise levels of the high-exposure workers with 85 +/- 8 dBA were significantly higher than those of the low-exposure workers with 59 +/- 4 dBA (P < 0.05). We found a significant difference of 16 +/- 6 mm Hg in sleep-time systolic blood pressure (SBP) existed between 2 exposure groups, and a marginal increase of 1 mm Hg SBP per 1-dBA increase in occupational noise exposure at a 60-minute lag time during work (P = 0.07). Occupational noise exposure had both transient and sustained effects on workers' SBP.

Adult↗
PubMed2005

Hearing loss associated with smoking and occupational noise exposure in a Japanese metal working company.

The effects of smoking on hearing loss within the context of atherosclerosis was assessed, and the statistical interaction of occupational noise evaluated. A cross-sectional study was conducted in 397 Japanese males working at a metal factory, aged 21-66 years, in a periodical health checkup. The following information was obtained: two smoking indices of smoking status and Brinkman index, occupational noise exposures and atherosclerotic risk factors (body mass index, blood pressure, serum cholesterol, hemoglobin A1c, atherosclerosis index). Hearing acuity was measured at 4 kHz using a pure-tone audiometer in a quiet room. Among the total subjects, 55 (13.9%) were identified as having hearing loss at 4 kHz, and 151 (38.0%) were currently exposed to occupational noise. When adjusted for age and occupational noise exposure, odds ratios (95% confidence intervals) of hearing loss were 3.16 (1.04, 9.62) for past smokers and 3.39 (1.05, 11.01) for heavy smokers (Brinkman index >750 cigarettes per day x number of years), compared with never-smokers. Statistical interaction of occupational noise exposure was insignificant with the association between smoking and hearing loss. When including atherosclerotic risk factors in a multiple model, there were no significant associations between hearing loss and either smoking or any other factors (i.e., occupational noise and atherosclerotic factors). Smoking was found to be associated with hearing loss beyond occupational noise exposure, and this association seemed to be masked by atherosclerotic factors, suggesting that the direction of the atherosclerotic effect on the relationship might need to be explored between smoking and hearing impairment.

Adult↗
PubMedDate not supplied

[Assessment of occupational noise exposure: methodology, measurement error, evaluation criteria].

BACKGROUND: Occupational noise exposure can be monitored directly by personal sampling or indirectly, by area sampling. Personal sampling is performed using an integrating sound level meter, worn by the worker while performing his/her job. When area sampling is used, measurements need to be made in all locations where a typical worker stays while performing his/her tasks; the respective partial lengths of exposure need to be accurately monitored, and the time-weighted average sound level of the measured noise levels must be calculated. OBJECTIVES: Current regulations identify three different thresholds, corresponding to different types of action, but they do not propose any standard criteria to decide whether a threshold has been exceeded. Defining standard procedures to assess occupational noise exposure and identifying such thresholds is crucial. METHODS: Using empirical data collected in the field, the effects are illustrated of the number of sampling locations and of the partial lengths of exposure on area sampling measurements, and the effects of duration of noise exposure on both area and personal samplings. RESULTS: When dealing with area samplings, an accurate definition of both sampling locations and partial lengths of exposure is crucial. When arbitrary decisions are taken in selecting sampling locations and/or establishing partial lengths of exposure, spatial changes in noise level and operator' displacements while performing his/her tasks may affect results. Sampling for less than the duration of noise exposure is the major contributor to measurement error, particularly under conditions of unpredictable variation in noise level. In fact, as noise level in the non-monitored time fraction is unknown, measurement error cannot be determined. We estimate that, even under the most favorable circumstances, sampling should last not less than 40% of the duration of a given noise-generating occurrence, for repeated measurements to be dispersed within a range not wider than that generated by the instrumental error. Inter-daily variability is another important aspect in personal noise exposure evaluation. This is a general occurrence, whose effects cannot be controlled by simply considering weekly instead of daily exposures. Results of an investigation, covering about 60 different jobs within a primary aluminum plant, show an inter-daily variability in noise exposure greater than 5 dBA in about 75% of cases. CONCLUSIONS: Personal sampling, when correctly performed and covering the total duration of exposure, provides the most reliable result as it integrates noise over all locations where the worker actually stays while performing his/her tasks, and over the total length of time spent in each task. We propose extending personal sampling to the total duration of actual noise exposure as the standard procedure for monitoring daily personal noise exposure, and valid for the majority of work places. When the range of daily noise exposure includes one regulatory threshold, corresponding to a given type of action, we propose as a standard decision criterion to refer prudentially to the upper 95% confidence limit of the LEP,d arithmetic mean. Such criterion would allow to standardize procedures and decision methods, with the prospect of further improvements in the assessment of exposure to noise.

Humans↗
PubMed1984

Occupational noise exposure and hearing loss characteristics of a blue-collar population.

Recent studies of health effects from chronic exposure to noise in the workplace have not consistently addressed nonoccupational variables. A cross-sectional study was conducted with 197 randomly selected male hourly workers from a noisy plant (greater than or equal to 89 dBA) in Pittsburgh to fully assess noise exposure and hearing loss, incorporating information on duration of exposure, noise level, occupational and medical histories, audiometric evaluation, and external noise sources. Population audiometric profiles are characteristic of noise-induced hearing loss; mean hearing thresholds for press room men were significantly higher at 2, 3, and 6 kHz (p less than or equal to .05). Only 40% of the men consistently wore hearing protection. Recent use of ototoxic drugs, noisy hobbies/second jobs, military service, family history of hearing loss, and ear-related problems were not found to have a significant effect on hearing levels at high frequencies, suggesting that observed hearing losses were of an occupational origin.

Adult↗
PubMed1995

[Occupational noise exposure and hypertension].

The hypothesis that occupational noise exposure is positively associated with hypertension was examined in a cross-sectional study carried out on a group of patients who were enrolled at the Occupational Health Unit of the Unified Health System, situated in Salvador city, the capital of Bahia state, Brazil. Data were obtained from 276 medical records, corresponding to all patients newly registered during the first six months of 1992. Data on noise exposure come from both reported occupational exposure history and clinical diagnosis of occupational noise-induced hearing loss. Hypertension diagnosis complies with World Health Organization criteria, as well as with the history of antihypertensive treatment. Stratified analysis and unconditional logistic regression modeling show results that do not support the study hypothesis: there are no differences between systolic or diastolic blood pressure or between proportion of hypertension for exposed and non exposed groups. However, statiscally significant (alpha = 0.05) increment of the effect measured was reported among workers who reported low educational level (below elementary). This could be another evidence of socially related inequalities underlying exposure distribution among workers at the workplace, which should be addressed, at greater depth, in future studies.

Adult↗
PubMed1988

Occupational noise exposure during pregnancy: a case control study.

The possible effects of occupational noise on human pregnancy were examined in a case-control study. The case groups consisted of 284 women with premature deliveries and of 299 women with full-term, low birth weight infants (below the 25th centile), each case having a matched pair. The whole material, all cases and controls included, comprised 1166 women. The percentage of employment in the whole material was 77.8; there were no differences between the case women and their controls. Rather few women (N = 26; 3.5%) reported occupational noise (greater than or equal to 81 dB; Leq(A)8h) during their pregnancies and our study revealed no significant difference between the cases (N = 14) and the controls (N = 12) with regard to noise exposure. Because of the small number of exposed women conclusions have to be drawn carefully. Nevertheless, noise cannot be regarded as a major risk for prematurity or low birth weight of human newborns in Finnish society. The women with reported noise exposure had significantly more inconvenience at work than other working women. They also had significantly more numerous and longer sick leaves than other working women.

Epidemiologic Methods↗
PubMed1986

Is occupational noise exposure during pregnancy a risk factor of damage to the auditory system of the fetus?

In the Province of Quebec, the regulated daily noise exposure limit is 90 dBA-8h. This limit value also applies to pregnant women. Experimental studies suggest however, that this standard is not sufficiently stringent to protect the auditory system of the fetus, particularly in cases of low-frequency noise exposure. An exploratory study was undertaken to assess this possibility. A total of 131 children were examined. Their mothers had worked, while pregnant with that child, in noise conditions ranging from 65 to 95 dBA-8h. Results show a three-fold increase in the risk of having a high-frequency hearing loss in the children whose mothers were exposed to noise in the range between a LAeq,9 m of 85 to 95 dB, and a significant increase in the risk of hearing loss at a frequency of 4000 Hz when these exposures involved a strong component of low-frequency noise.

Female↗
PubMed2006

Occupational noise exposure and sensorineural hearing loss among workers of a steel rolling mill.

Hearing loss is one of the most common chronic health conditions and has important implications for the patient's quality of life. However, hearing loss is substantially underestimated and under treated. The purpose of this study was to determine the prevalence of sensorineural hearing loss among the workers in a steel rolling mill in Nigeria. Each of the 150 randomly selected subjects had a structured questionnaire administered to them, followed by a full otological examination. Of these, 116 had tympanometry and pure-tone audiometry. Also a noise mapping of their respective work units was done. The workers were exposed to noise levels varying from 49 to 93 dBA. About 28.2% of the 103 who had their audiogram analysed had mild to moderate sensorineural hearing loss in their better ear and 56.8% of them had mild to moderate sensorineural hearing loss in their worse ear. The pure-tone average and the average hearing thresholds at 4 kHz for the groups significantly increased with an increasing noise exposure level. The prevalence of sensorineural hearing loss among the study population is high; and noise exposure is at least contributory. Pre-employment and regular audiometry while on the job is highly recommended.

Adult↗
PubMed2005

Long-term exposure to occupational noise alters the cortical organization of sound processing.

OBJECTIVE: Long-term exposure to noise may cause an altered hemispheric lateralization of speech processing even in silent conditions. We examined whether this lateralization shift is speech specific or occurs also for other sounds. METHODS: Brain responses from 10 healthy noise-exposed workers (>5 years) and 10 matched controls were recorded with a 32-channel electroencephalogram in two conditions, one including standard and deviant speech sounds, the other non-speech sounds, with novel sounds in both. RESULTS: The deviant-sound elicited mismatch negativity (MMN) was larger to non-speech than speech sounds in control subjects, while it did not differ between the sound types in the noise-exposed subjects. Moreover, the MMN to speech sounds was lateralized to the right hemisphere in exposed workers, while it was left-hemisphere predominant in control subjects. No group topography difference was found for non-speech sounds. The deviant sounds that were close in formant space to the standards elicited a longer MMN latency in both speech and non-speech conditions in exposed subjects than controls. No group differences were found for cortical responses to novel sounds. CONCLUSIONS: Long-term noise exposure altered the strength and the hemispheric organization of speech-sound discrimination and decreased the speed of sound-change processing. SIGNIFICANCE: Subpathological changes in cortical responses to sounds may occur even in subjects without a peripheral damage but continuously exposed to noisy auditory environments.

Adult↗