High Levels Of Exposure Research Articles

Hedge Accounting Disclosures and Sustainable Growth of Listed Deposit Money Banks in Nigeria

The primary problem facing listed deposit money banks in Nigeria is their struggle to achieve sustainable growth in a volatile economic environment. This study investigated the impact of hedge accounting disclosures on the sustainable growth of these banks, focusing on commodity hedge disclosure, interest rate hedge disclosure, and foreign exchange rate disclosure, while controlling for market capitalization. Using an ex post facto research design, the study analyzed secondary data from 11 selected banks over a period of 10 years from 2014 to 2023. The method of data analysis was random effect regression technique. The findings revealed that commodity hedge disclosure (COMD) and interest rate hedge disclosure (INTD) have significant positive effects on the sustainable growth rates of listed deposit money banks in Nigeria. Conversely, foreign exchange rate disclosure (FEXD) has a significant negative effect on sustainable growth, indicating that high levels of foreign exchange risk exposure, when disclosed, may reduce investor confidence and perceived stability. The study concluded that hedge accounting disclosures significantly impact sustainable growth of listed deposit money banks in Nigeria. It recommended the management of listed deposit money banks in Nigeria should enhance commodity and interest rate hedge disclosures to improve the quality of foreign exchange risk communication.

MiRNA-driven sensitization of breast cancer cells to Doxorubicin treatment following exposure to low dose of Zinc Oxide nanoparticles.

The impact of Engineered nanomaterials (ENMs) (i.e., Zinc Oxide nanoparticles (ZnO NPs)) on human health has been investigated at high and unrealistic exposure levels, overlooking the potential indirect harm of subtoxic and long exposures. Therefore, this study aimed to investigate the impacts of subtoxic concentrations of zinc oxide (ZnO NPs) on breast cancer cells' response to Doxorubicin. Zinc oxide nanoparticles caused a concentration-dependent reduction of cell viability in multiple breast cancer cell lines. A subtoxic concentration of 1.56µg/mL (i.e., no observed adverse effect level) was used in subsequent mechanistic studies. Molecularly, miRNA profiling revealed significant downregulation of 13 oncogenic miRNAs (OncomiRs) in cells exposed to the sub-toxic dose of ZnO NPs followed by doxorubicin treatment. Our comprehensive bioinformatic analysis has identified 617 target genes enriched in ten pathways, mainly regulating gene expression and transcription, cell cycle, and apoptotic cell death. Several tumor suppressor genes emerged as validated direct targets of the 13 OncomiRs, including TFDP2, YWHAG, SMAD2, SMAD4, CDKN1A, CDKN1B, BCL2L11, and TGIF2. This study insinuates the importance of miRNAs in regulating the responsiveness of cancer cells to chemotherapy. Our findings further indicate that being exposed to environmental ENMs, even at levels below toxicity, might still modulate cancer cells' response to chemotherapy, which highlights the need to reestablish endpoints of ENM exposure and toxicity in cancer patients receiving chemotherapeutics.

Examining the relationship between religious volunteering and mental health screeners among firefighters

ABSTRACT Firefighters experience a high level of traumatic incidents in their work. This high level of exposure puts them at risk for trauma-related symptoms. These trauma symptoms include PTSD, suicide risk, alcohol misuse, and depression, and anxiety. Furthermore, repeated exposure has been found to lead to desensitization, flashbacks, irritability, and PTSD. Exposure to natural disasters may also impact ecospirituality. A survey was designed to include the Life Events Checklist, PHQ-9, GAD-7, PCL-5, and the SBQ-R. This survey was administered to firefighters from Northwest Florida in the fall of 2020 and spring of 2021. Participants were found to have higher levels of PTSD, anxiety, depression, and suicidal risk than the general population. Participants were further asked about their volunteering for religious organization activity. A significant relationship was found between volunteering for religious organization and mental health screeners. Religious volunteering predicted lower levels of PTSD symptoms, depression, and anxiety. The effect size was small.

Determinants of cervical cancer screening among women of childbearing age in four sub-Saharan African countries: insights from large population surveys

BackgroundCervical cancer is the most common cause of cancer-related mortality among women in Africa. Cervical cancer screening in women is associated with decreased incidence and mortality of cervical cancer. There is a dearth of recent data regarding the prevalence and associated factors of cervical cancer screening in sub-Saharan Africa. Therefore, this study is intended to determine the prevalence and associated factors impacting cervical cancer screening among women in four sub-Saharan African countries.MethodsData from the recent demographic and health surveys of four countries in sub-Saharan Africa conducted between 2022 and 2023. Multilevel mixed-effects logistic regression was used to determine the factors associated with the outcome variable. Variables with a p-value < 0.05 were declared statistically significant.ResultsThe prevalence of cervical cancer screening among women of childbearing age in four sub-Saharan African countries was 8.90% (95% CI: 8.67%, 9.13%). At the individual level, being older, educated, non-breastfeeding, employed, wealthier, sexually active, using contraceptives, having media exposure, visiting healthcare facilities in the last 12 months, and residing in urban areas were associated with higher odds of cervical cancer screening. At the community level, being from communities with a high level of literacy and media exposure increases the odds of cervical cancer screening among women in sub-Saharan Africa.ConclusionThe prevalence of cervical cancer screening among childbearing-age women was found to be low. To improve cervical cancer screening practices among women of childbearing age, it is therefore advised to support women’s empowerment, mass media campaigns, and regular visits to healthcare facilities.

Close relationships with caregivers as protective factor for the mental health and functioning of war-affected Congolese youth

BackgroundSupportive social connections are a crucial determinant of the mental health and adjustment of youth in conflict-torn regions. Conflict-affected youth face particular risks to their well-being due to high levels of trauma exposure and perpetration of violent acts as members of armed groups and post-conflict discrimination. However, little is known about the possible protective role of close relationships with caregivers in the aftermath of trauma. This study examined whether a higher perceived quality of relationships with caregivers would attenuate the associations between exposure to traumatic experiences and four indicators of adjustment (posttraumatic stress symptoms [PTSS], emotional problems, behavioural problems, criminal behaviour) in a sample of 268 war-affected youth (61.2% male, Mage = 16.31 years) living in Bukavu, Democratic Republic of Congo. More than half of the present sample (56.7%) were former members of armed groups.MethodsData were collected using quantitative structured interviews and analyzed through regression models using the PROCESS macro.ResultsHigher cumulative trauma exposure was significantly related to higher levels of PTSS and emotional problems, while more frequent perpetration of war-related violence was significantly related to higher levels of PTSS, behavioural problems, and criminal behavior. The perceived quality of relationships with caregivers significantly moderated the associations between youth’s cumulative trauma exposure and all four outcomes. At higher perceived quality of relationships with caregivers, the associations between trauma exposure and emotional problems, behavioural problems, and criminal behaviour were no longer significant and the association with PTSS was significantly weakened. Higher perceived quality of relationships with caregivers was also directly significantly related to lower levels of mental health problems and criminal behaviour.ConclusionsThe findings suggest that interventions that focus on strengthening relationships with caregivers are crucial for supporting the mental health and functioning of youth who experienced and perpetrated war-related violence.

Examining the Independent and Interactive Carryover Effects of Cognitive and Physical Exertions on Physical Performance.

This study compared the effects of prior cognitive, physical, and concurrent exertion on physical performance. Fatiguing cognitive and physical exertions have been shown to negatively affect subsequent task performance. However, it is not clearly understood if concurrent physical and cognitive effort may exaggerate the negative carryover effects on physical task performance when compared to cognitive or physical exertion alone. Twenty-five participants completed four isometric handgrip endurance trials on different days. The endurance trials were preceded by four, 15-minute experimental manipulations (cognitive, physical, concurrent, control). Electromyography (EMG) and force tracing performance were monitored, with handgrip strength measured pre and post. Subjective ratings of mental and physical fatigue, as well as affect, motivation, and task self-efficacy, were also assessed. Handgrip strength decreased following both physical (-14.4% MVC) and concurrent (-12.3% MVC) exertion manipulations, with no changes being observed for the cognitive and control conditions. No differences were observed across conditions for endurance time, EMG, nor tracing performance. When compared to the control conditions, perceptions of mental and physical fatigue were higher following the experimental manipulation. Endurance trial self-efficacy was lower for the mental, physical and concurrent conditions compared to control. The concurrent condition resulted in similar decreases in strength as the physical fatigue condition, but otherwise resulted in similar carryover effects on endurance performance across all conditions. Further study is required at higher exposure levels, or for longer exposure durations, to further probe the influence of concurrent physical and cognitive effort on task performance. Concurrent cognitive and physical effort resulted in similar physical performance decrements to physical effort alone.

Forecasting Daily Air Quality Index and Early Warning System for Estimating Ambient Air Pollution on Road Networks Using Gaussian Dispersion Model with Deep Learning Algorithm

The rapid growth of the vehicle population is a major factor in heavy air pollution and public health issues. Traffic-related air pollutants (TRAPs) on roads are often much higher than ambient values, leading to high exposure levels in vehicles. This research proposes a hybrid forecasting model for early detection and early warning systems (EWS) of road networks during real-world travels. Data is collected from Kannur, Calicut, Palakkad, and Coimbatore using real-time sensors, including surrounding discussion information, activity information, vehicle speed, and stopping events. The study predicts ambient air quality (AAQ) levels on the road network using the Gaussian Dispersion model (GDM) and measures the risk sensitivity of PM10 and PM2.5 in selected regions. This helps formulate powerful prevention strategies and prevent negative health impacts. The air pollution module for predicting concentration has an innovative hybridization model that combines an improved cuckoo search (CS) and differential evolution (DE) algorithm with a stacked LSTM model to increase forecasting accuracy of six major environmental pollution levels. This model predicts the AAQ level and is effective and robust for warning one day before the pollutant event occurs based on the risk level of an ambient air pollutant from the RN.

Joint exposure to multiple air pollutants, genetic risk, and incident psoriasis: a large-scale prospective cohort study.

Air pollution and genetic risk have been found to contribute to both onset and development of psoriasis. However, the extent to which genetic susceptibility modifies the effects of air pollutants on the risk of incident psoriasis remains unknown. Our study aimed to assess the association between joint exposure to multiple air pollutants and the risk of psoriasis and the modification by the genetic susceptibility. This prospective study included 451,064 participants with complete air pollution data and free of psoriasis at baseline from the UK Biobank. All participants were enrolled from 2006 to 2010 and followed up to 2022. The air pollution score (APS) was calculated to assess the joint exposure to multiple air pollutants, including particulate matter (PM) with diameters ≤ 2.5 μm (PM2.5), between 2.5 and 10 μm (PM2.5-10), and ≤ 10 μm (PM10), as well as nitrogen dioxide (NO2) and nitrogen oxides (NOx). To evaluate the genetic risk, the polygenic risk score (PRS) for psoriasis was constructed. The Cox proportional hazard models were used to assess the association of air pollution and genetic susceptibility with the risk of psoriasis. Stratified analyses were conducted based on the individual characteristics. During a median follow-up of 13.79 years, 4414 psoriasis events were recorded. The hazard ratios (HRs) [95% confidence intervals (CIs)] for psoriasis were 1.036 (0.936-1.147), 1.091 (0.987-1.206), 1.159 (1.048-1.283), and 1.163 (1.052-1.286) in higher quintile groups compared with the lowest quintile of APS (P trend <0.05). When considering genetic susceptibility, participants with high PRS and high APS had the greatest risk of incident psoriasis [HR (95% CI): 1.962 (1.630-2.362)] than those with low PRS and low APS. The HRs (95% CIs) for PM2.5-10, NOx, PM2.5 absorbance, PM2.5, NO2, and PM10 in the group with high exposure level and genetic risk were 1.831 (1.537-2.181), 1.722 (1.431-2.073), 1.698 (1.416-2.037), 1.619 (1.353-1.938), 1.504 (1.252-1.806), and 1.425 (1.192-1.704), respectively. Long-term exposure to various air pollutants is positively associated with an increased risk of incident psoriasis, particularly in individuals with high genetic risk. More comprehensive measures are needed to reduce the air pollution levels for better prevention of psoriasis.

High levels of terrestrial gamma radiation exposure in the Kopili Fault Zone on the eastern wedge of the Shillong Plateau, India

High levels of terrestrial gamma radiation exposure in the Kopili Fault Zone on the eastern wedge of the Shillong Plateau, India

Knowledge and awareness of ketoacidosis associated with high exposure to acetone-containing products: A crosssectional assessment

Purpose: To assess the knowledge and awareness of the Jordanian public about the hazards associated with high levels of exposure to acetone-containing products. Methods: The study was conducted between September 2019 and December 2020. An electronic anonymous questionnaire was distributed via different channels to be self-completed by the study population. Socio-demographic characteristics, knowledge about acetone-containing nail polish removers and sterilizing products, and awareness about the risk of ketoacidosis associated with high degree of exposure to these products, were assessed. Results: The findings revealed that a majority of participants were aware of the presence of acetone in nail polish removers (92.61 %) and sterilizing products (84.41 %), regardless of gender, age, educational type and educational level. In addition, females (70.4 or 83.0 %), youngest age group (70.7 or 83.0 %), those with health-related education (56.6 or 76.0 %), and graduates (72.0 or 83.9 %) were significantly (p &lt; 0.05) more aware about the safety of these products if inhaled or exposed to flame sources, respectively, than their peers. Moreover, concerning the risks of developing ketoacidosis and raised liver ketone levels as hazards associated with the high degree of exposure to acetone-containing products, females (44.2, 41.9 and 50.6 %), those with health-related education (64.1, 63.4 and 73.3 %), youngest age group (47.4, 44.6 and 56.5 %), and graduates (45.3, 43.5 and 52.8 %), respectively, were significantly more aware than the others (p &lt; 0.05). Conclusion: These findings indicate signs of significantly poor awareness about the serious risks associated with acetone-caused ketoacidosis among the study population. Therefore, well-organized educational campaigns are needed to enlighten graduates with health-related education and to improve public perception of the health hazards associated with human exposure to acetone-containing products.

NEUROTOXIC EFFECTS OF ENVIRONMENTAL POLLUTANTS ON PEDIATRIC BRAIN DEVELOPMENT

The development of neurological disorders such as Parkinson’s disease, Alzheimer’s disease, ADHD, Autism become and the presence of environmental pollutants. In this particular study, the impact of neurotoxicity of the environmental pollutants on a child’s brain development are described. This study includes the formation of a literature review which was used for gathering concepts regarding the environmental pollutants, their relationship with neurological disorders, and the cognitive development of children. The method of this research holds the use of secondary data. The results have shown that high levels of pollution exposure ultimately decreases the cognitive characteristics of a child.

Regional BDE-209 emission, environmental fate and risks: Methods establishment, data filling and feature analysis

BDE-209 is an emerging environmental contaminant that poses a significant threat to human health. Despite its inclusion in the Stockholm Convention, the current regional emission levels, environmental fate, and corresponding risks remain unclear, especially with the ongoing release of BDE-209 during the disposal of waste electrical and electronic equipment. The significant gaps in BDE-209 emission data highlight the need for a regional approach to better understand these issues. Therefore, we established a method to identify regional BDE-209 emissions, environmental fate, and risks in the Guangdong–Hong Kong–Macao Greater Bay Area (GBA) using a substance flow analysis framework, fugacity model, and risk model. Our results showed: (1) Despite the increasing pressure of electronic waste, emissions have decreased with gradual strengthening of restrictions. The stage with the highest contribution to emissions is flame-retardant plastic production, which accounts for 41 % of emissions, followed by informal treatment (36 %). (2) The largest BDE-209 emissions are into air and soil, at 7.23 t and 4.56 t, respectively, and the highest reserves are in soil and sediment. (3) Infants and young children have the highest levels of exposure and cancer risk. This research helps fill the multi-regional data gap for BDE-209 and clarify the complex regional emission situation in the GBA.

Exposure to Air Pollutants and Myocardial Infarction Incidence: A UK Biobank Study Exploring Gene-Environment Interaction.

Unraveling gene-environment interaction can provide a novel insight into early disease prevention. Nevertheless, current understanding of the interplay between genetic predisposition and air pollution in relation to myocardial infarction (MI) risk remains limited. Furthermore, the potential long-term influence of air pollutants on MI incidence risk warrants more conclusive evidence in a community population. We investigated interactions between genetic predisposition and exposure to air pollutants on MI incidence. This study incorporated a sample of 456,354 UK Biobank participants and annual mean air pollution (, , , and ) from the UK Department for Environment, Food and Rural Affairs (2006-2021). The Cox proportional hazards model was employed to explore MI incidence after chronic air pollutants exposure. By quantifying genetic risk through the calculation of polygenic risk score (PRS), this study further examined the interactions between genetic risk and exposure to air pollutants in the development of MI on both additive and multiplicative scales. Among 456,354 participants, 9,114 incident MI events were observed during a median follow-up of 12.08 y. Chronic exposure to air pollutants was linked with an increased risk of MI occurrence. Specifically, the hazard ratios (per interquartile range) were 1.12 (95% CI: 1.10, 1.13) for , 1.20 (95% CI: 1.19, 1.22) for , 1.13 (95% CI: 1.12, 1.15) for , and 1.12 (95% CI: 1.11, 1.13) for . In terms of the joint effects, participants with high PRS and high level of air pollution exposure exhibited the greatest risk of MI among all study participants ( to 324%). Remarkably, both multiplicative and additive interactions were detected in the ambient air pollutants exposure and genetic risk on the incidence of MI. There were interactions between exposure to ambient air pollutants and genetic susceptibility on the risk of MI onset. Moreover, the joint effects of these two exposures were greater than the effect of each factor alone. https://doi.org/10.1289/EHP14291.

Characterizing the role of unpredictability within different dimensions of early life adversity.

Dimensional models of early life adversity highlight the distinct roles of deprivation and threat in shaping neurocognitive development and mental health. However, relatively little is known about the role of unpredictability within each dimension. We estimated both the average levels of, and the temporal unpredictability of deprivation and threat exposure during adolescence in a high-risk, longitudinal sample of 1354 youth (Pathways to Desistance study). We then related these estimates to later life psychological distress, and Antisocial and Borderline personality traits, and tested whether any effects are mediated by future orientation. High average levels of both deprivation and threat exposure were found to be associated with worse mental health on all three outcomes, but only the effects on Antisocial and Borderline personality traits were mediated by decreased future orientation, a pattern consistent with evolutionary models of psychopathology. Unpredictability in deprivation exposure proved to be associated with increased psychological distress and a higher number of Borderline traits, but with increased future orientation. There was some evidence of unpredictability in threat exposure buffering against the detrimental developmental effects of average threat levels. Our results suggest that the effects of unpredictability are distinct within different dimensions of early life adversity.

Hurricane exposure, personality traits, and perceived changes in health and health behaviors

Using data from a retrospective pre-/post-longitudinal study of young adults impacted by Hurricane Harvey in 2017 (N = 330), we investigated the main and moderating effects of hurricane exposure and the Big Five personality traits on perceived changes in health and health behaviors. Linear regressions showed that more hurricane exposure was associated with worse perceived diet changes. People who were more extraverted tended to perceive better health changes, whereas people who were more neurotic tended to perceive worse overall health, sleep, diet, and exercise changes. The association between hurricane exposure and perceived diet changes was stronger for people higher in conscientiousness, such that at high levels of hurricane exposure, people who were more conscientious tended to perceive the worst diet changes.

Acoustic comfort in primary- and nursery-school canteens: From measurements to recommendations

Canteens usually have critical acoustic conditions resulting from the need to maximize the number of occupants while minimizing volume. Thus, in the absence of specific sound absorbing treatments, very high sound pressure levels are usually observed resulting in significant impairment of communication (with increased vocal effort of speakers and reduced speech intelligibility), and dangerously high exposure levels for workers. The present paper reports acoustic measurements carried out in a nursery school canteen having a volume of 212 m3 and seating about 50 children, and two primary school canteens having volumes of 656 m3 (seating 150 children) and 367 m3 (seating 107 children). Reverberation time was measured in each room as well as sound pressure levels during peak occupation (averaged over 15-minute intervals), resulting in A-weighted sound pressure levels spanning between 81 dB (in the nursery school) and 90 dB in the primary schools. Starting from the observed values, considerations about the group-size of the occupants as a function of age were made, and recommendations were finally given to guide the acoustic correction of similar spaces.

Frequency dependence and harmonic distortion of stapes displacement and intracochlear pressure in response to very high level sounds

Previous reports have suggested that intracochlear pressures (PIC) measured at the base of the cochlea increase directly proportionally with stapes displacement (DStap) in response to moderately high (<130 dB SPL) level sounds. Consistent with this assumption, we have reported that for low frequency sounds (<1 kHz), stapes displacement and intracochlear pressures increase linearly with sound pressure level (SPL) for moderately high levels (<130 dB SPL), but saturate at higher exposure levels (>130 dB SPL). However, the magnitudes of each response were found to be frequency dependent, thus the relationship between DStap and PIC may vary at higher frequencies or higher levels.In order to further examine this frequency and level dependence, measurements of DStap and PIC were made in cadaveric human temporal bones prepared with a mastoidectomy and extended facial recess to expose the ossicular chain. PIC was measured in scala vestibuli (PSV) and scala tympani (PST) simultaneously with SPL in the external auditory canal (PEAC) and laser Doppler vibrometry (LDV) measurements of stapes velocity (VStap). Consistent with prior reports, DStap and PSV increased proportionally with sound pressure level in the ear canal up to a frequency-dependent saturation point, above which both DStap and PSV showed a distinct deviation from proportionality with PEAC, suggesting that their relationship may remain constant at these high frequencies. Likewise, while the asymptotic value, and SPL at which saturation occurred were frequency dependent in both DStap and PSV, the reduction in gain with increasing SPL above this level was constant above this level at all frequencies, and the magnitude of responses at harmonics of the driving frequency increased with increasing level, consistent with harmonic distortion via peak clipping. Importantly, this nonlinear distortion shifts the energy arriving at the inner ear to higher frequencies than are present in incident stimulus, thus exposing the high frequency sensitive components of the auditory system to more noise than would be expected from measurement of that stimulus on its own. Overall, responses suggest that the cochlear representation of very high-level air conducted stimuli is limited by nonlinearities in the middle ear, and that this peak limiting leads to increased high frequency cochlear exposures than are present in the driving stimulus.

Is inflammatory change associated with psychological risk and resilience in high-risk military personnel?

IntroductionIn military populations, the potential for under-reporting of Post-traumatic Stress Disorder (PTSD) symptoms and challenges in recognising early changes can make it difficult to detect an emerging disorder. However, early...

Self-compassion and association with distress, depression, and anxiety among displaced Syrians: A population-based study.

Displaced communities are at increased risk of poor mental health with limited resources for treatment. Self-compassion moderates the impacts of stressors on mental health in high-income country general population samples, but its impact has not been described among people who have experienced displacement and associated trauma. The aim of this study was to characterize the associations between self-compassion, mental health, and resilience in a sample of displaced Syrian adults living in Jordan. This is a cross-sectional study using four validated survey tools measuring self-compassion, resilience, mental health, and traumatic exposure. Syrian adults who presented to four different community organizations serving refugees within Amman, Jordan were invited to participate. A total of 272 displaced Syrians were included in the final analysis. A majority of those surveyed were positive for emotional distress (84.6%), depression (85.7%), and anxiety (76.5%). In univariate analysis there was a significant lower risk of emotional distress, depression, and anxiety, with both higher resilience and self-compassion. However, in the multivariate model only self-compassion remained significantly associated with less emotional distress, depression, and anxiety, independent of resilience and other covariates. Female gender, poor financial stability, and high levels of traumatic exposure were also identified as persistent predictors of mental health morbidity. The findings of this study suggest that self-compassion is associated with less distress, depression, and anxiety in displaced individuals; suggesting it might be protective against poor mental health. Self-compassion is a modifiable factor that can be utilized as a tool by healthcare professionals and communities caring for refugees to promote positive mental health outcomes.

English Vowel Perception in Spanish-English Bilingual Preschoolers: Multiple-Talker Input Is Only Beneficial for Children With High Language Exposure Levels.

This study examines English vowel perception in Spanish-English bilingual preschoolers, comparing bilinguals' perception patterns to those of monolinguals and examining how child internal (age) and external variables (input quantity and input diversity) predict perceptual performance. Sixty children between 3;6 and 5;6 (years;months) of age participated in the study, 28 of whom were Spanish-English bilinguals and 32 English monolinguals. Perception was assessed through a forced-choice minimal-pair identification task in which children heard synthesized audio stimuli (i.e., "sheep" and "ship") that varied systematically along the /i-ɪ/ continuum and were asked to match them with one of two pictures. The data were analyzed with Bayesian mixed-effects logistic regression analyses, modeling responses as a function of continuum step, language background (monolingual or bilingual), age, English exposure (i.e., input quantity), and number of English input providers (i.e., input diversity). The results indicate that, despite displaying nonnative English stop voicing perception in a previous study, the same bilingual children showed English /i-ɪ/ perception patterns that did not differ from those of monolinguals. While age did not predict vowel perception, input quantity and diversity jointly interacted to moderate how well children perceived the /i-ɪ/ contrast. Specifically, diverse input promoted perceptual performance in children who received high levels of English exposure-and who presumably had more advanced English language skills, whereas it limited perceptual performance in children with more limited English exposure and skills. This study shows that bilingual children can show monolingual-like perception patterns for some sounds while displaying nontarget perception for others. This is the first study to demonstrate that language exposure mediates the role of input diversity on speech sound development, suggesting that varied input can be more or less beneficial for speech sound development based on the learner's language learning stage.