Contribution of outdoor noise-induced health risk in schools located in urbanized arid country

Ambient noise pollution is deemed as one of the major growing public health issues, especially in developing countries. Therefore, it is crucial to assess the impact of noise pollution on public health. The aim of this study is to investigate the health risk of noise exposure levels in three schools: Kaab Bin Zeyd of Basic Education (school A), Hail Al-Awamour Girls school (school B), and Al-Fikr School (school C) in Muscat, Oman. The study employed a survey of 300 students, dose-response models, and regression models to quantify health risk and to determine the relationship between noise levels and perceived noise annoyance sources. The study found average noise levels (L_Aeq) of school A (70.03±8.21 dBA), school B (69.54±7.75 dBA), and school C (55.95± 5.67 dBA) to be higher than WHO's outdoor schools environment standard of 55 dBA and European (EN16798-1) classroom's critical limits of 30-34 dBA. Most of the students from schools A (30.9%), B (33.3%), and C (63%) have reported noise produced from traffic as extremely annoyed compared to aircraft of 15.4%, 11.5%, and 27.2%, respectively. Regression analysis shows that perceived traffic noise was strongly correlated with L_Aeq in school A (R² =0.481), B (R² =0.121), and C (R² = 0.132) when compared with other subjective noise types. The health risk assessment results show that the percentage of highly annoyed (%HA) was higher in school A (15.2%) and school B (14.95%) than in school C (8.18%). The estimated highly sleep disturbed (%HSD) based on mean noise levels were almost the same in schools A (15.62%) and B (15.19%) but far higher compared to school C (6.01%). However, there was an association between the mean noise exposure levels and the risk of developing ischemic heart diseases (IHD) in school A (RR= 1.172, 95% CI: 1.020-1.334), school B (RR=1.167, 95% CI: 1.020-1.325), and school C (RR=1.051, 95% CI: 1.006-1.095). Moreover, attributable risk percentage (AR%) for school A (AR% =14.675, 95% CI: 2.028-25.037), school B (AR% =14.310, 95% CI: 1.960-24.528), and school C (AR% = 4.852, 95% CI:0.596-8.742) have shown that a substantial portion of the population could be prevented from developing IHD. It is expected that findings of the study can be applied in other arid regions with sprawl urbanized built environments.

Impact of COVID-19 pandemic on aircraft noise levels, annoyance, and health effects in an urban area in Oman

This study aimed at investigating aircraft noise exposure levels, their annoyance, and potential health effects among communities living within airport catchment areas during the COVID-19 pandemic. Both field measurements and an online survey approach were used to investigate aircraft noise exposure levels, annoyance, and general health effects among residents living near Muscat International Airport (MCT) in Muscat, Oman, amid the COVID-19 period. The study found a drastic decline in aircraft noise levels due to the introduction of COVID-19 intervention measures such as lockdowns, social distancing, and closure of airports. In June 2020, during the COVID-19 pandemic, average daily aircraft noise levels of LAeq (39.9 dB(A)) and Lmax (49.7 dB(A)) was observed compared to the previous year (April-May 2019) of 58.5 and 76.8 dB(A), indicating aircraft noise reductions level of 32% and 35%, respectively. The results of the online social survey among 187 participants showed that most (58.8%) of the respondents did not feel that the level of noise produced by aircraft causes annoyance. During the day, the vast majority of the interviewees did not complain of any annoyance during the morning (45.5%), afternoon (39.6%), and evening (31%) with only < 4% of residents have reported a very high degree of annoyance of during COVID-19 pandemic period. Very few people (17%) did complain of experiencing general health problems while 29% did not know of any potential health effects that could be attributed to aircraft noise exposures. Aircraft noise annoyance complaints among the As-Seeb residents during the pre-COVID-19 pandemic periods were reported to be extremely high reaching about 84% compared to 41% during this current COVID-19 pandemic period. These findings support the need to develop future sustainable noise mitigation policies in order to help reduce noise exposures and improve human health during post-COVID-19 pandemic periods.

Effect of ambient noise on indoor environments in a health care facility in Oman

Hospital-noise levels can induce physiological responses and affect sleep quality, which could contribute to cardiovascular-related health problems. Till date, high-resolution hospital noise exposure assessment studies have not received much attention in Oman. This study aims at assessing sound pressure levels across hospital wards and intensive care unit (ICU) rooms to determine annoyance and potential health effects based on perception and risk estimates. An indoor exposure assessment using high precision noise sensors was conducted in a female medical ward (FMW), isolated ward (SLW), emergency ward (EMW), and intensive care unit (ICU) in a public hospital in Muscat city, Oman. Self-administered questionnaire was randomly distributed among respondents using both online and field survey approach to ascertain annoyance, health effects, and potential risks associated with exposure. The study found that 24-h noise levels (L_Aeq) ranged from 55.2 to 61.7 dB(A) in the hospital wards and ICU rooms, which exceeded WHO's hospital indoor rooms critical limit of 35 dB(A) by 58-76%. A total of 150 participants took part in the survey. Among the respondents, 53% reported moderate annoyance at the hospital wards, while 56% felt sensitivity to the noise levels. Noise annoyance was reported by the majority of the patients across the various wards and emergency rooms as causing slight annoyance (50%) and intermittent sleep disturbances (49%). The majority (73%) of the medical staff have complained that the current noise levels affect overall work performance (p = 0.004), while 70% of them have further complained of it as a cause of workplace distraction (p = 0.011). Logistic binary regression analysis has revealed that the complaint of noise sensitivity has a positive association with noise levels in VCW (OR: 1.54; 95% CI: 0.92-2.58), and reported loss of concentration by the medical staff also associated with noise levels at the EMW (OR: 1.61; 95% CI: 0.65-4.01). Quantitative risk estimates showed that both the percentages of highly annoyed (HA) persons (16%), and highly sleep-disturbed (HSD) persons (9%) were very high in FMW, while ICU was found to have the lowest risk. However, the greater number of the respondents (87%) believed that there are possibilities of mitigating (p < 0.001) the current noise levels.

A critical review of environmental and public health impacts from the activities of evaporation ponds

Evaporation ponds (EVPs) are among the most cost-effective, and simple wastewater treatment technologies used in many regions/countries with high solar radiation levels. However, its operational limitations, which include the overflow of wastewater, leakages via liners, and large surface area of the EVP that is exposed to atmosphere, creates a negative feedback to the environment. Therefore, the main aim of this review study of more than a hundred works published a little all over the continents is to provide a summary of various contaminations that are associated with EVPs activities through different environmental compartments. In addition, the impacts of EVP on fauna, human health including the current on-site sustainable mitigation strategies were also reviewed. The first conclusion from this study shows that the most commonly contaminants released into surface waters, groundwater, soil and sediments were heavy metals, pesticides, herbicides, selenium, including several major anions and cations. Non-methane hydrocarbons (NMHCs), volatile organic compounds (VOCs), and particulate matters (PMs) were the main air pollutants emitted from the surfaces of an EVP. Limited data is available about the emissions of atmospheric greenhouse gas (GHGs) especially carbon dioxide (CO₂) and methane (CH₄) from EVP surfaces. Migratory birds and aquatic organisms are the most vulnerable fauna as EVP wastewaters can cause obstruction of movements, affect diversity, and causes mortalities following the exposure to the toxic wastewater. The study revealed limited data about the potential health risk associated with occupational and environmental exposure to radiological hazards and contaminated drinking water from EVP activities. On-site EVP treatment strategies using bioremediation and electrochemical treatment technologies have shown to be a promising sustainable mitigation approach. Knowledge gaps in areas of GHGs monitoring/modeling, pollution exposure estimation and health risk assessments are urgently required to gain deeper understanding about the impact of EVP activities, and incorporate them into future EVP designs.

Assessment of noise levels and induced annoyance in nearby residential areas of an airport region in Oman

There is adequate evidence from epidemiological studies showing an association between noise exposures and incidence of cardiovascular diseases and cognitive impairment among exposed populations. This study aimed to investigate noise exposure levels in an airport region and their effects on the nearby two neighborhood communities (i.e., Al Seeb and Bawshar). To achieve this, noise levels were measured across 15 different points within the communities for more than 3 weeks at a median distance of 3.5 km from the airport runways using a sound level analyzer. In addition, we conducted an online social survey in a random sampling of a total of 913 residents who were living closer to the airport. A combination of a 5-point scale and 3-point Likert scale was used to assess the resident population's noise annoyance and the potential health impacts. The results revealed that the majority of the measured points have noise levels (55.71-65.24 L_Aeq dBA) exceeding both Oman and WHO critical limits. There was a general decrease in noise levels at points further away from the runways; thus, at points 2.5, 4.8, and 8.8 km, sound pressure levels were found to be 63.08, 57.41, and 52.31 dBA, respectively. However, steady noise levels were observed throughout most of the daily (24 h) measurements indicating continual exposures. Overall, 44.6% of residents reported noise annoyance level as very high, with Al Seeb inhabitants (46%) eliciting a greater percentage of annoyance levels compared to Bawshar (5%) due to their closer proximity to the airport. Also, the noise was significantly (p ˂ 0.001) associated with sleep disturbance, insomnia, irritation, and frightening. The majority of the residents complained of an increase in insomnia (41.5%), stress (34.3%), headache (47.3%), and cardiovascular diseases (16.2%). With the question of reducing noise exposures, about 41% of the respondents have plans of relocating to distant areas with low noise levels.

Characterization and exposure assessment to urban air toxics across Middle Eastern and North African countries: a review

Middle East and North African (MENA) countries over the decades are experiencing rapid industrial and infrastructural growth combined with being the global hub of oil and gas industries. These economic transformations are associated with release of air pollutants including urban air toxics (UAT) through industrial, traffic, and constructional activities into ambient urban environments. UAT concentrations levels may exacerbate in most MENA countries considering high number of vehicular traffic populations and petrochemical industries which are one of the main sources of this pollutant. Therefore, the main objective of the study is to review major findings of UAT levels in urban areas across thirteen (13) MENA countries. The study characterizes various measured UAT, assesses their concentrations in ambient environment, and identifies their major sources of emissions by reviewing more than 100 relevant UAT papers across the selected MENA countries. It was found that benzene, heavy metals, formaldehyde, and dioxin-like compounds are the most reported UAT. The study concluded that road traffic, fuel stations, and petrochemical industries were identified as the main sources of ambient UAT levels. It was further reported that most of the studies were based on short-term ambient environment with limited studies in indoor environments. Therefore, it is highly recommended that future research should focus on innovative health impact assessment and epidemiological studies from exposure to UAT levels. Also embarking on sustainable mitigation approaches through urban greenery, eco-industrial estates infrastructural developments, and renewable energy shares will reduce UAT levels and improve human health.

Exposure assessment to road traffic noise levels and health effects in an arid urban area

Road traffic noise exposures have been recognized as serious environmental health concerns, especially in most developing countries with arid climate conditions, rapid increase in vehicle population, and limited traffic management systems. The excessive noise exposure level is associated with increase in the incidence of cardiovascular diseases and anxiety, including annoyance. This study aimed at determining traffic noise levels in residential areas, including the assessment of its annoyance and health effects based on the people's perception and reportage. To do so, field measurement and traffic noise modeling were carried out in six road points to estimate the current noise levels along various roads close to human inhabitants in Muscat Governorate, Sultanate of Oman. The detailed measured noise levels in urban residential areas across the selected roads showed that noise levels have exceeded the local and international threshold limits at all locations during the entire day. The high sound levels (48.0-56.3 dBA) were observed using the US Federal Highway Administration's Traffic Noise Model (TNM, version 2.5) results, which were in agreement with the observed (56.3-60.4 dBA) data. To assess health implication to residents through interviews (n = 208), annoyance at home was found to be little (32%), moderate (28%), and high (9%) in comparison with workplace settings of 42%, 43%, and 15%, respectively. Nineteen percent of the interviewees had difficulties in sleeping, while 19.8% experienced stress due to road traffic noise exposures. Moreover, a strong association (p < 0.05) was established between the use and objection of noise barriers. The study revealed high noise levels and the prevalence of annoyance and health effects among the exposed population. Therefore, immediate action is required to tackle the current noise levels.