Excessive Noise Exposure Research Articles

Noise Exposure and Hearing Loss Among Landscape and Groundskeepers.

Excessive noise exposure within the working population is a health concern that has received increased attention in recent years. Levels have been established by national organizations that reflect safe exposure, but many kinds of equipment used in the landscaping and groundskeeper industries still exceed them. While noise risks are often long-term in nature and occur with cumulative exposure, prevention and exposure methods can still be used by employers to protect their workers' long-term health. Recalling the hierarchy of controls established by the National Institute for Occupational Health and Safety (NIOSH), various strategies can be implemented without creating excessive supervisory burden and with minimal costs. Occupational health nurses can further help reduce excessive noise exposure by encouraging the use of an easy-to-use noise-level assessment app created by NIOSH.

Road traffic noise pollution and prevalence of ischemic heart disease: modelling potential association and abatement strategies in noise-exposed areas.

In many developing countries with surging vehicular traffic and inadequate traffic management, excessive road traffic noise exposure poses substantial health concerns, linked to increased stress, insomnia and other metabolic disorders. This study aims to assess the linkage between sociodemographic factors, traffic noise levels in residential areas and health effects using a cross-sectional study analyzing respondents' perceptions and reports. Noise levels were measured at 57 locations in Srinagar, India, using noise level meter. Sound PLAN software was employed to generate noise contour maps, enabling the visualization of noise monitoring locations and facilitating the assessment of noise levels along routes in proximity to residential areas. Correlation analysis showed a strong linear relationship between field-measured and modelled noise (r2 = 0.88). Further, a questionnaire-based survey was carried out near the sampling points to evaluate the association of ischemic heart disease with traffic noise. Residents exposed to noise levels (Lden > 60dB(A)) were found to have a 2.24 times higher odds ratio. Compared to females, males reported a 16% higher prevalence of the disease. Multi-faceted policy strategies involving noise mapping initiatives, source noise standards, traffic flow urban mobility optimization, smart city initiatives and stringent litigatory measures could significantly reduce its detrimental impact on public health. Finally, this study envisions a region-specific strong regulatory framework for integrating noise pollution mitigation strategies into the public health action plans of developing nations.

ДОСЛІДЖЕННЯ АКУСТИЧНОГО СЕРЕДОВИЩА СУЧАСНИХ БАГАТОФУНКЦІЙНИХ КОМПЛЕКСІВ

This article examines the issue of acoustic comfort and noise pollution within multifunctional residential complexes in Lviv, where public facilities are situated in the ground-level space. The relevance of such a study is confirmed by numerous scientific conclusions that excessive noise exposure negatively affects human health, while this problem remains poorly understood and ignored in Ukraine. According to the research method, 5 multifunctional complexes were selected in different parts of Lviv. Within these complexes, 5–6 points were installed, and measurements were made using the RFT 00 014 pulse sound level meter on different days and at different times of the day. The choice of points was primarily based on the geometric shapes of the buildings (shape breaks, confined spaces, etc.) According to the results of the field measurements, it was found that most multifunctional complexes comply with the state standards for acoustic comfort, but some buildings were exposed to excessive noise load. Hence, a multitude of regularities and correlations were established between the excessive sound level meter values and the characteristics of these complexes. For example, buildings with a closed, perimeter form of construction provide noise reduction of up to 15–20 dB, but its effectiveness can be reduced due to large through passages and traffic directly next to the building. Moreover, the impact of reverberation within such covered courtyards remains unclear, as a cursory analysis shows that playground activity causes an increase in noise of 5 to 15 dB, but the sample size of this study is not sufficient to draw objective conclusions. In addition, the road surface material is an important factor, especially in the context of historic city centres where it is made of basalt paving stones. Traffic on such roads generates a much higher noise level than traffic on asphalt. Following these results, several possible solutions to the noise load problem were analysed, and the importance of conducting similar studies in the future was proven.

Race, historical redlining, and contemporary transportation noise disparities in the United States.

Legacies of discriminatory federal housing practices-e.g., racialized property appraisal by the Home Owners' Loan Corporation (HOLC) and institutionalized redlining by the Federal Housing Administration-include disparate present-day environmental health outcomes. Noise pollution is health-harming, but just one study has associated contemporary noise with redlining in some HOLC-mapped United States (US) cities, while two national studies found associations between greater neighborhood-level people of color composition and increased noise. No studies have examined noise pollution exposure disparities across all HOLC-mapped cities or based on the intersection of race/ethnicity and redlining. We address three objectives: (1) Assess disparities in fine-scale, per person transportation noise exposures by historical redlining status across all HOLC-mapped cities. (2) Quantify disparities in noise exposures by race/ethnicity nationwide. (3) Explore interactions between redlining status and race/ethnicity in noise exposures. We analyzed three data sources: (1) complete digital HOLC maps of ordered investment risk grades (A-D), (2) fine-scale (30 m) estimates of transportation noise levels (year-2020), and (3) sociodemographic characteristics of individuals in year-2020 census blocks. We find an approximately monotonic association for excess transportation noise with HOLC grade, marked by a pronounced exposure increase (17.4 dBA or 3× loudness) between contemporary residents of grade A (highest-graded) and D (lowest-graded) neighborhoods, a pattern consistent across HOLC-mapped cities. People of color experience ~7 dBA greater (2× louder) excess transportation noise exposures than White people nationwide, a pattern consistent across US counties. Noise exposure disparities are larger by HOLC grade than by race/ethnicity. However, contemporary racial/ethnic noise exposure disparities persist within each HOLC grade at levels approximating those disparities existing in ungraded areas, indicating that historical redlining is one of multiple discriminatory practices shaping contemporary national soundscape injustices. Findings illustrate how historical redlining and broader racialized inequalities in US society have shaped environmental injustices nationwide. Excessive noise exposures harm human health. Communities of color in the United States experience disparate noise exposures, although previous studies are limited by reliance upon aggregated data. They are also disproportionately concentrated in historically redlined areas. Legacies of redlining include persistent racial and economic inequalities and environmental health disparities. Here, we conduct the first complete national examination of contemporary noise pollution disparities with respect to historical redlining and race/ethnicity. Findings advance understanding of the historical roots and enduring salience of race-based disparities in noise pollution exposures and can inform efforts to address these disparities through noise pollution policy-making.

Noise annoyance due to different sources is associated with tinnitus presence and distress in the general population.

The pathophysiology of tinnitus is not yet fully understood. Although there is a large amount of evidence associating traffic noise exposure with non-auditory health outcomes, there is no evidence regarding the impact of noise annoyance on auditory disorders such as tinnitus. Thus, we aimed to investigate the association between noise annoyance due to different sources and tinnitus presence and distress in the general population. Data of 6813 participants from a large German population-based cohort were used (Gutenberg Health Study). Participants were asked about the presence of tinnitus and how much they were bothered by it. In addition, information on annoyance from road traffic, aircraft, railways, industrial, and neighborhood noise during the day and sleep was collected through validated questionnaires. The prevalence of tinnitus was 27.3%, and the predominant sources of noise annoyance in these subjects were aircraft, neighborhood, and road traffic noise. Overall, logistic regression results demonstrated consistent positive associations between annoyance due to different noise sources and prevalent risk of tinnitus with increases in odds ratios ranging from 4 to 11% after adjustment for sex, age, and socioeconomic status. Likewise, consistent increases in odds ratios were observed for tinnitus distress in subjects with prevalent tinnitus. For instance, neighborhood noise annoyance during the sleep was associated with a 26% increase in tinnitus distress (OR 1.26, 95% CI 1.13; 1.39). This is the first study investigating the association between noise annoyance and tinnitus presence and distress in a large cohort of the general population. Our results indicate consistent and positive associations between various sources of noise annoyance and tinnitus. These unprecedented findings are highly relevant as noise annoyance and tinnitus are widespread. The precise etiology and locus of tinnitus remain unknown, but excessive noise exposure is thought to be among the major causes. This study suggests that transportation and neighborhood noise levels thought merely to contribute to annoyance and non-auditory health effects may be sufficient to cause or exacerbate tinnitus.

Effects of 90 dB pure tone exposure on auditory and cardio-cerebral system functions in macaque monkeys

Excessive noise exposure presents significant health risks to humans, affecting not just the auditory system but also the cardiovascular and central nervous systems. This study focused on three male macaque monkeys as subjects. 90 dB sound pressure level (SPL) pure tone exposure (frequency: 500Hz, repetition rate: 40Hz, 1 min per day, continuously exposed for 5 days) was administered. Assessments were performed before exposure, during exposure, immediately after exposure, and at 7-, 14-, and 28-days post-exposure, employing auditory brainstem response (ABR) tests, electrocardiograms (ECG), and electroencephalograms (EEG). The study found that the average threshold for the Ⅴ wave in the right ear increased by around 30 dB SPL right after exposure (P < 0.01) compared to pre-exposure. This elevation returned to normal within 7 days. The ECG results indicated that one of the macaque monkeys exhibited an RS-type QRS wave, and inverted T waves from immediately after exposure to 14 days, which normalized at 28 days. The other two monkeys showed no significant changes in their ECG parameters. Changes in EEG parameters demonstrated that main brain regions exhibited significant activation at 40Hz during noise exposure. After noise exposure, the power spectral density (PSD) in main brain regions, particularly those represented by the temporal lobe, exhibited a decreasing trend across all frequency bands, with no clear recovery over time. In summary, exposure to 90 dB SPL noise results in impaired auditory systems, aberrant brain functionality, and abnormal electrocardiographic indicators, albeit with individual variations. It has implications for establishing noise protection standards, although the precise mechanisms require further exploration by integrating pathological and behavioral indicators.

The Monitoring Environmental noise in Coffee Production, CCT/NCBA Companies in Bidau Lesidere Villige, Dili District Dili City Timor Leste

Noise-induced hearing loss is hearing loss caused by exposure to quite loud noise over a long period of time and is usually caused by noise in the work environment, in this case the company environment. Working environment noise is a major problem in occupational health which is a standard of OSH in various companies, the relationship between excessive noise exposure and hearing loss has been known since ancient times. Various epidemiological studies of noise-induced hearing loss have explored the relationship or risk factors between work, exposure to noise levels and the degree of hearing loss. The purpose of this study was to determine and survey the noise of electronic machines on hearing loss. The research method used is a quantitative, observational method using a cross observational study design.

Preventing Excessive Noise Exposure in Infants, Children, and Adolescents.

Noise affects people of all ages. Noise-induced hearing loss, a major problem for adults, is also a problem for young people. Sensorineural hearing loss is usually irreversible. Environmental noise, such as traffic noise, can affect learning, physiologic parameters, sleep, and quality of life. Children and adolescents have unique vulnerabilities. Infants and young children must rely on adults to remove them from noisy situations; children may not recognize hazardous noise exposures; teenagers often do not understand consequences of high exposure to music from personal listening devices or attending concerts and dances. Personal listening devices are increasingly used, even by small children. Environmental noise has disproportionate effects on underserved communities. This statement and its accompanying technical report review common sources and effects of noise as well as specific pediatric exposures. Because noise exposure often starts in infancy and effects are cumulative, more attention to noise in everyday activities is needed starting early in life. Pediatricians can potentially lessen harms by raising awareness of children's specific vulnerabilities to noise. Safer listening is possible. Noise exposure is underrecognized as a serious public health issue in the United States. Greater awareness of noise hazards is needed at a societal level.

Preventing Excessive Noise Exposure in Infants, Children, and Adolescents.

Noise exposure is a major cause of hearing loss in adults. Yet, noise affects people of all ages, and noise-induced hearing loss is also a problem for young people. Sensorineural hearing loss caused by noise and other toxic exposures is usually irreversible. Environmental noise, such as traffic noise, can affect learning, physiologic parameters, and quality of life. Children and adolescents have unique vulnerabilities to noise. Children may be exposed beginning in NICUs and well-baby nurseries, at home, at school, in their neighborhoods, and in recreational settings. Personal listening devices are increasingly used, even by small children. Infants and young children cannot remove themselves from noisy situations and must rely on adults to do so, children may not recognize hazardous noise exposures, and teenagers generally do not understand the consequences of high exposure to music from personal listening devices or attending concerts and dances. Environmental noise exposure has disproportionate effects on underserved communities. In this report and the accompanying policy statement, common sources of noise and effects on hearing at different life stages are reviewed. Noise-abatement interventions in various settings are discussed. Because noise exposure often starts in infancy and its effects result mainly from cumulative exposure to loud noise over long periods of time, more attention is needed to its presence in everyday activities starting early in life. Listening to music and attending dances, concerts, and celebratory and other events are sources of joy, pleasure, and relaxation for many people. These situations, however, often result in potentially harmful noise exposures. Pediatricians can potentially lessen exposures, including promotion of safer listening, by raising awareness in parents, children, and teenagers. Noise exposure is underrecognized as a serious public health issue in the United States, with exposure limits enforceable only in workplaces and not for the general public, including children and adolescents. Greater awareness of noise hazards is needed at a societal level.

Balance beam crossing times are slower after noise exposure in rats.

The vestibular system integrates signals related to vision, head position, gravity, motion, and body position to provide stability during motion through the environment. Disruption in any of these systems can reduce agility and lead to changes in ability to safely navigate one's environment. Causes of vestibular decline are diverse; however, excessive noise exposure can lead to otolith organ dysfunction. Specifically, 120 decibel (dB) sound pressure level (SPL) 1.5 kHz-centered 3-octave band noise (1.5 kHz 3OBN) causes peripheral vestibular dysfunction in rats, measured by vestibular short-latency evoked potential (VsEP) and reduced calretinin-immunolabeling of calyx-only afferent terminals in the striolar region of the saccule. The present study examined the functional impact of this noise exposure condition, examining changes in motor performance after noise exposure with a balance beam crossing task. Balance beam crossing time in rats was assessed for 19 weeks before and 5 weeks after noise exposure. Balance beam crossings were scored to assess proficiency in the task. When animals were proficient, they received a single exposure to 120 dB SPL 3-octave band noise. During the initial training phase slower crossing times and higher scores, including multiple failures were observed. This was followed by a period of significant improvement leading to proficiency, characterized by fast and stable crossing times and consistently low scores. After noise exposure, crossing times were significantly elevated from baseline for 4-weeks. A total of 5 weeks after noise exposure, crossing times improved, and though still trending higher than baseline, they were no longer significantly different from baseline. These findings show that the noise-induced peripheral vestibular changes we previously observed at cellular and electro-physiological levels also have an impact at a functional level. It has been previously shown that imbalance is associated with slower walking speed in older adults and aged rats. These findings in noise-exposed rats may have implications for people who experience noisy environments and for seniors with a history of noise exposure who also experience balance disorders and may be at increased fall risk.

Adult mice with noise-induced hearing loss exhibited temporal ordering memory deficits accompanied by microglia-associated neuroplastic changes in the medial prefrontal cortex

Acquired peripheral hearing loss in midlife is considered the primary modifiable risk factor for dementia, while the underlying pathological mechanism remains poorly understood. Excessive noise exposure is the most common cause of acquired peripheral hearing loss in modern society. This study was designed to investigate the impact of noise-induced hearing loss (NIHL) on cognition, with a focus on the medial prefrontal cortex (mPFC), a brain region that is involved in both auditory and cognitive processes and is highly affected in patients with cognitive impairment. Adult C57BL/6 J mice were randomly assigned to a control group and seven noise groups: 0HPN, 12HPN, 1DPN, 3DPN, 7DPN, 14DPN, and 28DPN, which were exposed to broadband noise at a 123 dB sound pressure level (SPL) for 2 h and sacrificed immediately (0 h), 12 h, or 1, 3, 7, 14, or 28 days post-noise exposure (HPN, DPN), respectively. Hearing assessment, behavioral tests, and neuromorphological studies in the mPFC were performed in control and 28DPN mice. All experimental animals were included in the time-course analysis of serum corticosterone (CORT) levels and mPFC microglial morphology. The results illustrated that noise exposure induced early-onset transient serum CORT elevation and permanent moderate-to-severe hearing loss in mice. 28DPN mice, in which permanent NIHL has been verified, exhibited impaired performance in temporal order object recognition tasks concomitant with reduced structural complexity of mPFC pyramidal neurons. The time-course immunohistochemical analysis in the mPFC revealed significantly higher morphological microglial activation at 14 and 28 DPN, preceded by a remarkably higher amount of microglial engulfed postsynaptic marker PSD95 at 7 DPN. Additionally, lipid accumulation in microglia was observed in 7DPN, 14DPN and 28DPN mice, suggesting a driving role of lipid handling deficits following excessive phagocytosis of synaptic elements in delayed and sustained microglial abnormalities. These findings provide fundamentally novel information concerning mPFC-related cognitive impairment in mice with NIHL and empirical evidence suggesting the involvement of microglial malfunction in the mPFC neurodegenerative consequences of NIHL.

Noise-induced Hearing Loss among Non-Medical Workers in a Healthcare Institution

Introduction: The effects of prolonged and excessive noise exposure on healthcare workers have not been studied. This study aims to estimate the prevalence of hearing loss among such workers and correlate the degree of hearing loss with age, duration of exposure, and coexisting illnesses. Methods: A retrospective review of 117 clinical records was conducted on 179 employees working in areas of excessive noise in a tertiary care hospital. Correlations between categorical variables were made using the Chi-square and Fisher's exact tests, while an independent samples t-test was used to compare means for continuous variables. Binary logistic regression was used to quantify the strength of correlations through an odds ratio and 95% confidence interval. Results: A clinical evaluation was conducted to assess hearing loss on employees from various departments, including Boiler Section, Central Sterile Supply Department (CSSD), Laundry, Prosthetics and Orthotics Laboratory, and Dietary. The median age of the participants was 37 years. Out of the 116 participants who underwent by audiological tests, 63.8% had sensorineural hearing loss and 68.5% had absent otoacoustic emissions in at least one frequency. The incidence of hearing loss was found to increase with age (p = 0.037). A significant correlation was noted between hearing loss and the duration of noise exposure of more than 10 years (p = 0.0013). Considering all areas together, a significantly higher proportion of employees with hearing loss was observer (p = 0.044), with 69.5% in the CSSD. Conclusion: Noise-induced hearing loss is a prevalent occupational health hazard in healthcare settings. The risk of developing hearing loss increases with the duration of work in a noise-generating area.

Auditory and Nonauditory Risks Related to Roadway Traffic Noise: An Overview for Audiologists

Purpose: Roadway traffic noise is recognized as a public health concern as it is associated with negative auditory and nonauditory health outcomes. This article provides an overview of roadway noise exposure and the related negative health consequences. The overview specifically includes information on the sources of roadway traffic noise, noise exposure measurement techniques, historic and current U.S. policy regarding roadway noise exposure, and practical suggestions for audiologists for mitigating the negative consequences of excessive roadway noise exposure. The purpose of this overview is to educate audiologists of these effects. Conclusions: Roadway traffic noise exposure is a public health concern both nationally and globally. Nonauditory effects of excessive roadway noise exposure are better understood than auditory effects; however, more evidence is needed to thoroughly to assess the risks to the public. Opportunities in the United States exist at the federal and local level to better understand the effects of roadway traffic noise and mitigate undesirable auditory and nonauditory health consequences. To address noise exposure as a growing public health concern, audiologists should be aware of the effects that roadway noise exposure has on the general population as well as provide education and preventative health care services.

Assessment of noise-induced hearing loss (NIHL) of weaving factory workers in West Bengal, India - a pilot study

Introduction: Excessive noise exposure is one of the majorly considered occupational stress for industrial workers. The operation of steel weaving machinery producing a high level of noise such as weaving machines, crimping machines, and hydraulic press machines for a prolonged period increases the risk of developing noise-induced hearing loss (NIHL). The main aim of the study was to assess the auditory health of the workers exposed to a high level of noise in a steel weaving factory and the prevalence of NIHL among workers. Methods: 26 subjects in the age group of 25-55 years from a steel weaving industry of Chinsurah town, Hooghly district of West Bengal were randomly selected with 5 years of exposure for the study. The control group was selected from the same age group, socioeconomic status and geographical location and having no history of such exposure. The physiological parameters of the workers, noise levels in the workplace and auditory functions and the risk of NIHL were assessed by standardized protocol and statistically analyzed. Results: The study indicated that steel weaving factory workers had significantly reduced hearing functionality at 4000Hz and 6000Hz in the left ear respectively. It also revealed that the workers were exposed to high noise exposure of 131dB near weaving machine, 113dB at crimping machine, and 84dB at hydraulic press machine respectively. Conclusion: A high level of noise exposure leads to deterioration in the hearing capabilities of the steel weaving industrial workers. Implementation of ergonomic interventions in the workplace and the use of personal protective equipment (PPE) may decrease the prevalence of NIHL and can help to prevent hearing loss in workers.

Assessing the performance of the simple noise chart method for construction noise prediction in earth-moving activity

Construction activity has long been associated with health problems caused by excessive noise exposure from the high noise emission machines. Indeed, predicting noise levels during the planning stages of a construction project can be challenging, particularly when considering complex and dynamic noise sources. This study aims to determine the accuracy and reliability of the simple prediction charts method in predicting construction noise. A case study of piling activity had been conducted at a construction site in Klang valley, Malaysia. The results showed that the average predicted noise levels were slightly higher than the actual measurements, but the highest absolute difference was only 0.9 dBA. The simple prediction charts can approximate the sound pressure level with high reliability with R2 values of 0.9959. These results show that the simple prediction charts can accurately and reliably predict construction noise levels, providing a useful tool for predicting the noise levels from earthmoving machines at any point of the construction site. With the help of these charts, construction noise practitioners can more easily anticipate and manage potential noise issues.

Pre-employment hearing threshold levels of 59,601 Australian male coal miners compared to an otologically normal international male population (ISO7029:2019)

Objective This study compared the pre-employment median hearing threshold level (HTL) distribution from a population of coal miners from New South Wales (NSW), Australia, to an otologically normal, age-matched population described by the International Standards Organisation (ISO) ISO 7029:2019, to determine any differences. Design This was an observational, retrospective, repeated cross-sectional study. Study sample De-identified audiometric records of 59,601 male employees entering NSW coal mining in three representative five-year periods between 1991 and 2015 were utilised. Results The median HTL deviation of the mining population was statistically significantly different (p < 0.05) from the ISO population, for almost all analyses. Overall, the mining population cohorts have higher (worse) median HTLs compared to the ISO population. The greatest difference occurs at 4 kHz in older age groups, likely indicating noise-induced hearing loss. Conclusion These findings indicate that some NSW coal mine workers commence their careers with evidence of pre-existing hearing loss (HL), in an industry with excessive noise exposures. These results provide Australian mining and other noisy industries with evidence to support a review of hearing conservation strategies to improve mitigation of hearing loss across the working lifespan.

Noise exposure in early adulthood causes age-dependent and brain region-specific impairments in cognitive function.

Hearing loss is a chronic health condition that affects millions of people worldwide. In addition to age-related hearing impairment, excessive noise exposure is a leading cause of hearing loss. Beyond the devastating effects of hearing impairment itself, epidemiological studies have identified hearing loss as a major risk factor for age-related cognitive decline, including dementia. At present, we currently lack a full understanding of the brain regions and underlying molecular changes that are responsible for mediating the link between hearing loss and cognitive impairment across aging. In the present study, we exposed 6-month-old rats to an occupational-like noise (100 dB SPL, 4 h/day × 30 days) or sham exposure and investigated both hippocampal-dependent (i.e., spatial learning and memory, assessed using the Morris water maze) and striatal-dependent (i.e., visuomotor associative learning, assessed using an operant-conditioning task) cognitive function across aging at 7, 10, and 13 months of age. We also investigated brain region-specific changes in microglial expression following noise/sham exposure in order to assess the potential contribution of this cell type to noise-induced cognitive impairments. Consistent with human studies, the occupational-like noise exposure resulted in high-frequency hearing loss, evidenced by a significant increase in hearing thresholds at 20 kHz. Ultimately, our results suggest that not all higher-level cognitive tasks or their associated brain regions appear to be equally susceptible to noise-induced deficits during aging, as the occupational-like noise exposure caused an age-dependent deficit in spatial but not visuomotor associative learning, as well as altered microglial expression in the hippocampus but not the striatum. Interestingly, we found no significant relationships between spatial learning ability and the level of hearing loss or altered microglial density in the hippocampus following noise exposure, suggesting that other changes in the brain likely contribute to hippocampal-dependent cognitive dysfunction following noise exposure. Lastly, we found that a subset of younger animals also showed noise-induced deficits in spatial learning; findings which suggest that noise exposure may represent an increased risk for cognitive impairment in vulnerable subjects. Overall, our findings highlight that even a mild occupational-like noise exposure earlier in adulthood can have long lasting implications for cognitive function later in life.

What is the safe noise level to prevent noise-induced hearing loss?

Noise causes short-term mechanical and chemical changes in the cochlea, transduced into electrical signals transmitted to the brain. Excessive noise exposure overwhelms the cochlea’s ability to reverse these changes, causing noise-induced hearing loss (NIHL). The Centers for Disease Control and Prevention state that NIHL is the only completely preventable type of hearing loss. What is the evidence-based safe noise exposure level to prevent NIHL? The National Institute for Occupational Safety and Health (NIOSH) recommended exposure level (REL), 85 dBA, does not prevent NIHL. Occupational exposures are calculated for 8 hours/day, 240 days/year, for 40 years. To calculate the noise exposure level to prevent NIHL in the public, 70 dB for 24 hours (Leq(24) = 70), the Environmental Protection Agency (EPA) adjusted the REL for 24 hours/day, 365 days/year exposure. The actual safe noise exposure must be lower than 70 dB because 1) the EPA did not adjust for lifetime noise exposure, 2) NIOSH based its REL on limited-frequency pure tone audiometry, an insensitive measure of auditory damage, and 3) non-occupational noise exposure has increased. The safe noise level may be as low as 55 dBA, the effective quiet level required for humans to recover from noise-induced temporary threshold shift.

Signal in the noise: Dimensions of predictability in the home auditory environment are associated with neurobehavioral measures of early infant sustained attention.

The home auditory environment influences the development of early language abilities, and excessive noise exposure is increasingly linked with deficits in language and reading scores in children. However, fewer studies have considered the role of noise exposure in shaping the development of attentional processing in early infancy, a foundational neurocognitive skill relevant for learning. Here, we used passive at-home auditory recording to investigate how multiple dimensions of infants' home auditory environments, including both the quantity and the predictability of auditory input, impacts neural and behavioral measures of sustained attention in a sociodemographically diverse sample of 3-month-old infants (N= 98 infants, 62 males; age M=3.48 months, SD=0.39; 52% Hispanic/Latino). Results indicated that infants who were exposed to more predictable patterns of auditory input in the home demonstrated longer overall time in sustained attention during laboratory assessments. In addition, infants' who experienced more predictable auditory input also demonstrated greater relative increases in electroencephalography frontal theta power during periods of sustained attention, a neural marker relevant to information processing and attentional control. These findings provide novel evidence into the importance of the predictability of early environmental inputs in shaping developing cortical circuitry and attentional systems from the first months of postnatal life.

Multiple health benefits of tulsi plants

Ayurveda's focus on healthy lifestyle practices and the regular consumption of adaptogenic herbs can address many of the major causes of global morbidity and mortality. Ayurvedic practitioners highly regard Tulsi (Ocimum sanctum Linn), and scientific research has confirmed its benefits. With its unique combination of pharmacological actions, tulsi has demonstrated its ability to address physical, chemical, metabolic, and psychological stress. There is evidence that tulsi protects organs and tissues against chemical and physical stress resulting from prolonged physical exertion, ischemia, physical restraint, excessive noise, and cold exposure. In addition to its beneficial effects on memory and cognitive functions as well as its anxiolytic and antidepressant properties, tulsi can counter metabolic stress, lowering blood glucose, blood pressure, and oxidized cholesterol levels. Due to its broad-spectrum antimicrobial activity, including activity against human and animal pathogens, tulsi can be used in treating wounds, animal rearing, preserving food and herbal raw materials, and traveller's health as well as hand sanitizers, mouthwashes and water purifiers. Plants grown for tulsi have spiritual significance and practical value, allowing growers to tap into nature's creative powers. Organic cultivation enables farmers to address food security issues, rural poverty, hunger and environmental degradation. Using ancient knowledge, tulsi is considered a symbol of wisdom in Ayurvedic medicine. Additionally, the Tulsi plant's roots, stem, fruit, and leaves have several phytochemical constituents that impart different therapeutic properties. Eugenol, vallinin, gallic acid, palmitic acid, oleic acid, and linoleic acid are some of these constituents. Many diseases can be treated with these phytochemicals extracted from plants. Tulsi is reported to have anti-ulcer, antioxidant, anti-inflammatory, anti-cancer, anti-diabetic, anti-arthritic, analgesic, anti-stress, anti-asthmatic, antifertility, Immunomodulation, and neuroprotective properties.