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Traffic emissions have been associated with a wide range of adverse health effects. Many schools are situated close to major roads, and as children spend much of their day in school, methods to reduce traffic-related air pollutant concentrations in the school environment are warranted. One promising method to reduce pollutant concentrations in schools is to alter the timing of the ventilation so that high ventilation time periods do not correspond to rush hour traffic. Health Canada, in collaboration with the Ottawa-Carleton District School Board, tested the effect of this action by collecting traffic-related air pollution data from four schools in Ottawa, Canada, during October and November 2013. A baseline and intervention period was assessed in each school. There were statistically significant ( P < 0.05) reductions in concentrations of most of the pollutants measured at the two late-start (9 AM start) schools, after adjusting for outdoor concentrations and the absolute indoor-outdoor temperature difference. The intervention at the early-start (8 AM start) schools did not have significant reductions in pollutant concentrations. Based on these findings, changing the timing of the ventilation may be a cost-effective mechanism of reducing traffic-related pollutants in late-start schools located near major roads. [ABSTRACT FROM AUTHOR]

Background: Few high-quality studies have evaluated associations between urinary glyphosate or its environmental degradate (aminomethylphosphonic acid (AMPA)] and preterm birth (PTB)., Objectives: To quantify associations between urinary glyphosate and AMPA and preterm birth in the pan-Canadian Maternal-Infant Research on Environmental Chemicals (MIREC) study and determine if associations differ by fetal sex., Methods: We measured first trimester urinary glyphosate and AMPA concentrations in MIREC participants who were recruited between 2008-2011 from 10 Canadian cities. Of the 1880 participants whose first trimester urine samples were analyzed for glyphosate or AMPA, 1765 delivered a singleton, live birth. Our primary outcome was preterm birth (PTB) defined as births occurring between 20 and <37 weeks. Secondary outcomes were spontaneous preterm births (sPTB) and gestational age. We modelled the hazard of PTB and sPTB using discrete time survival analysis with multivariable logistic regression to calculate odds ratios (OR). We used multivariable linear regression models to quantify associations between analytes and gestational age. To assess effect modification by fetal sex, we stratified all models and calculated interaction terms. In the logistic regressions models we additionally calculated the relative excess risk due to interaction., Results: Six percent (n = 106) of the study population delivered preterm, and 4.7% (n = 83) had a spontaneous preterm birth. Median specific-gravity standardized concentrations of glyphosate and AMPA were 0.25 and 0.21 µg/L. Associations between both glyphosate or AMPA and PTB, sPTB, and gestational age centered around the null value. The adjusted ORs of PTB for each doubling of glyphosate and AMPA concentrations were 0.98 (95% CI: 0.94, 1.03) and 0.99 (95% CI: 0.92, 1.06) respectively. We observed no evidence of differences by fetal sex., Conclusions: In this Canadian pregnancy cohort, neither glyphosate nor AMPA urinary concentrations was associated with PTB or reduced gestational length., (© 2024. Crown.)

In the event of a large-scale incident involving radiological or nuclear exposures, there is a potential for large numbers of individuals to have received doses of radiation sufficient to cause adverse health effects. It is imperative to quickly identify these individuals in order to provide information to the medical community to assist in making decisions about their treatment. The cytokinesis-block micronucleus assay is a well-established method for performing biodosimetry. This assay has previously been adapted to imaging flow cytometry and has been validated as a high-throughput option for providing dose estimates in the range of 0-10 Gy. The goal of this study was to test the ability to further optimize the assay by reducing the time of culture to 48 h from 68 h as well as reducing the volume of blood required for the analysis to 200 μL from 2 mL. These modifications would provide efficiencies in time and ease of processing impacting the ability to manage large numbers of samples and provide dose estimates in a timely manner. Results demonstrated that either the blood volume or the culture time could be reduced while maintaining dose estimates with sufficient accuracy for triage analysis. Reducing both the blood volume and culture time, however, resulted in poor dose estimates. In conclusion, depending on the needs of the scenario, either culture time or the blood volume could be reduced to improve the efficiency of analysis for mass casualty scenarios., Competing Interests: Declaration of Competing Interest None, (Crown Copyright © 2024. Published by Elsevier B.V. All rights reserved.)

Background: The use of hand sanitizers has been one of the key public health measures recommended to reduce the transmission of SARS-CoV-2 during the pandemic. As such, its daily use among the general population has reportedly increased dramatically since the onset of the COVID-19 pandemic., Objective: To better understand the impact of this recommendation, hand sanitizer use, including the frequency and amount handled, was examined among adults in a non-occupational setting and children in both the home and school/childcare settings., Methods: An online survey of Canadians (conducted from September to October 2021) was employed to estimate use frequency, amount, and pattern of hand sanitizer use., Results: Responses were received from 655 adults in the general population and 298 teachers of children up to the age of 18 years. The frequency of hand sanitizer use during the pandemic was found to be as high as 25 times per day in children and over 9 times per day in adults. Notable differences were found when comparing the frequency of hand sanitizer use by children in the home to children in a school or childcare setting., Significance: This is the first study, known to the authors, examining hand sanitizer use among children during the pandemic, including use in a childcare or school setting. This study illustrates the importance of examining the change in consumer behaviors during a pandemic and the need to look beyond the home when attempting to understand product use patterns in children., Impact Statement: This research explores uses of hand sanitizer, before and during pandemic conditions, in the general population of Canada with a particular focus on use among children. The results can be used to estimate exposure to chemicals in hand sanitizer from non-occupational use in Canada and among similar populations and signal the importance of examining changing consumer behaviors and use of consumer products in school settings, especially among children., (© 2022. The Author(s).)

Objective: To examine the association between individual and cumulative leisure noise exposure in addition to acceptable yearly exposure (AYE) and hearing outcomes among a nationally representative sample of Canadians., Design: Audiometry, distortion-product otoacoustic emissions (DPOAEs) and in-person questionnaires were used to evaluate hearing and leisure noise exposure across age, sex, and household income/education level. High-risk cumulative leisure noise exposure was defined as 85 dBA or greater for 40 h or more per week, with AYE calculations also based on this occupational limit., Study Sample: A randomised sample of 10,460 respondents, aged 6-79, completed questionnaires and hearing evaluations between 2012 and 2015., Results: Among 50-79 year olds, high-risk cumulative leisure noise was associated with increased odds of a notch while high exposure to farming/construction equipment noise was associated with hearing loss, notches and absent DPOAEs. No associations with hearing loss were found however, non-significant tendencies observed included higher mean hearing thresholds, notches and hearing loss odds., Conclusion: Educational outreach and monitoring of hearing among young and middle-aged populations exposed to hazardous leisure noise would be beneficial.

Evidence is building regarding the association between government implemented public health measures aimed at combating COVID-19 and their impacts on health. This study investigated the relationship between the stringency of public health measures implemented in Canada and self-reported mental health, physical health, stress, and wellbeing among a random sample of 6647 Canadians 18 years of age and older. The analysis was based on self-reported health data from the Canadian Perspectives on Environmental Noise Survey. This data was combined with the Oxford COVID-19 Government Response Tracker database, which included overall stringency index (SI), and four of its sub-components, i.e., school and business closures, restrictions on gatherings, and stay at home policies. Adjusted multivariate logistic regression models indicated that the magnitude of the overall SI was associated with higher or lower odds of reporting worse physical health, mental health, stress and/or overall wellbeing, depending on the measure evaluated. Similarly, policy directed at the four sub-components had varying impacts on the odds of reporting worse health, depending on the sub-component, the strength of the policy restriction, and the health outcome evaluated. The association between the strength of the public health measures and self-reported health, and how this may inform future policy, is discussed., (© 2023. Springer Nature Limited.)

Background: Toxic metals, like lead, are risk factors for preterm birth (PTB), but few studies have examined low levels found in most Canadians. Vitamin D, which may have antioxidant activity, protects against PTB., Objectives: In this study, we investigated the impact of toxic metals (lead, mercury, cadmium and arsenic) on PTB and examined if maternal plasma vitamin D concentrations modify these associations., Methods: We investigated whether concentrations of metals in whole blood measured in early and late pregnancy were associated with PTB (<37 weeks) and spontaneous PTB in 1851 live births from the Maternal-Infant Research on Environmental Chemicals Study using discrete time survival analysis. We also investigated whether the risk of PTB was modified by first-trimester plasma 25-hydroxyvitamin D (25OHD) concentrations., Results: Of 1851 live births, 6.1% (n = 113) were PTBs and 4.9% (n = 89) were spontaneous PTB. A 1 μg/dL increase in blood lead concentrations during pregnancy was associated with an increased risk of PTB (relative risk [RR] 1.48, 95% confidence interval [CI] 1.00, 2.20) and spontaneous PTB (RR 1.71, 95% CI 1.13, 2.60). The risk was higher in women with insufficient vitamin D concentrations (25OHD <50 nmol/L) for both PTB (RR 2.42, 95% CI 1.01, 5.79) and spontaneous PTB (RR 3.04, 95% CI 1.15, 8.04). However, an interaction on the additive scale was not present. Arsenic was associated with a higher risk of PTB (RR 1.10, 95% CI 1.02, 1.19) and spontaneous PTB (RR 1.11, 95% CI 1.03, 1.20) per 1 μg/L., Conclusions: Gestational exposure to low levels of lead and arsenic may increase the risk of PTB and spontaneous PTB; individuals with insufficient vitamin D may be more susceptible to the adverse effects of lead. Given our relatively small number of cases, we encourage testing of this hypothesis in other cohorts, especially those with vitamin D-deficient populations., (© 2023 His Majesty the King in Right of Canada and The Authors. Paediatric and Perinatal Epidemiology published by John Wiley & Sons Ltd. Reproduced with the permission of the Minister of Health.)

N,N-diethyl-m-toluamide (DEET) is an ingredient found in many consumer insect repellents and its use is recommended to Canadians by government agencies, including Health Canada, for protection against insect bites including mosquitos and ticks. The majority of research on DEET exposure and toxicokinetics in humans has focused on adult populations with little information from vulnerable populations, including children. We aimed to fill this knowledge gap by examining real-world exposure data for DEET and its metabolite 3-diethylcarbamoyl benzoic acid (DCBA) in a sample population of Canadian children. We conducted a 24-h observational exposure human biomonitoring study at three overnight summer camps in Ontario, Canada through July and August 2019. Participating children aged 7-13 years provided multiple spot urine samples over a 24-h period and completed a journal to document insect repellent use and factors that could influence absorption of DEET. Children were instructed to use insect repellent as they usually would while attending a summer camp. Exposure was quantified using the information from the participant's journal and the change in the mass of their insect repellent containers over the course of the study. A total of 389 urine samples were collected from 124 children. Among participants using insect repellent, urinary levels of DEET were elevated between 2 and 8 h post-application and decreased thereafter but remained qualitatively higher than concentrations in participants who did not use insect repellent on the study day, even at 18-22 h post-application. DCBA was the predominant metabolite of DEET exposure in urine. DCBA was elevated between 8 and 14 h post-application, and declined thereafter, but not to the level observed among those who did not use insect repellent on the study day. Children who used more insect repellent, or used higher concentration insect repellent (10%-30% DEET) excreted higher levels of DEET and DCBA. Excreted DEET and DCBA accounted for 0.001% (median) and 1.3% (median) of the estimated applied DEET, respectively. Children did not reach an undetectable level of DEET or DCBA in urine, even among those not using insect repellent during the study day, indicating a potentially complex multi-route exposure to insect repellents in a real world scenario. This work provides targeted biomonitoring data for children intentionally using DEET-based insect repellents for normal protective use, and will support the risk re-evaluation of DEET by Health Canada., Competing Interests: Declaration of competing interest The authors have no conflict of interest to declare., (Crown Copyright © 2022. Published by Elsevier GmbH. All rights reserved.)

The cytokinesis-block micronucleus assay is a well-established method to assess radiation-induced genetic damage in human cells. This assay has been adapted to imaging flow cytometry (IFC), allowing automated analysis of many cells, and eliminating the need to create microscope slides. Furthermore, to improve the efficiency of assay performance, a small-volume method previously developed was employed. Irradiated human blood samples were cultured, stained, and analyzed by IFC to produce images of the cells. Samples were run using both manual and 96-well plate automated acquisition. Multiple parameter-based image features were collected for each sample, and the results were compared to confirm that these acquisition methods are functionally identical. This paper details the multi-parametric analysis developed and the resulting calibration curves up to 10 Gy. The calibration curves were created using a quadratic random coefficient model with Poisson errors, as well as a logistic discriminant function. The curves were then validated with blinded, irradiated samples, using relative bias and relative mean square error. Overall, the accuracy of the dose estimates was adequate for triage dosimetry (within 1 Gy of the true dose) over 90% of the time for lower doses and about half the time for higher doses, with the lowest success rate between 5 and 6 Gy where the calibration curve reached its peak and there was the smallest change in MN/BNC with dose. This work describes the application of a novel multi-parametric analysis that fits the calibration curves and allows dose estimates up to 10 Gy, which were previously limited to 4 Gy. Furthermore, it demonstrates that the results from samples acquired manually and with the autosampler are functionally similar., (© 2023 The Author(s). Published by S. Karger AG, Basel.)

The Canadian Perspectives on Environmental Noise Survey (CPENS), conducted between April 12th, 2021 and May 25th, 2021 coincided with the third wave of the COVID-19 pandemic. Canadians 18 years of age and older (n = 6647) reported the degree to which the pandemic affected their physical health, mental health, stress, annoyance toward environmental and indoor noise, and overall well-being. Depending on the outcome evaluated, between 18 and 67% of respondents reported the measure as "somewhat" or "much worse" due to the pandemic. Stress was most affected, followed by mental health, overall well-being, physical health, annoyance toward environmental noise and annoyance toward indoor noise. Logistic regression models indicated that province, geographic region (rural/remote, suburban, urban), age, gender, poor physical/mental health, heart disease, a history of high sleep disturbance (in general) or diagnosed sleep disorders, anxiety/depression, working/schooling from home, and being retired significantly impacted the odds of reporting a worsening by the pandemic to varying degrees and directions, depending on the outcome. Indigenous status was unrelated to any of the modelled outcomes. Future research could address some of the noted study limitations and provide the data to determine if the observations on the reported measures of health are temporary, or long-lasting., (© 2022. Crown.)

Biomonitoring data of N,N-diethyl-meta-toluamide (DEET) in children is scarce and limited to controlled exposure and surveillance studies. We conducted a 24-hour observational exposure and human biomonitoring study designed to estimate use of and exposure to DEET-based insect repellents by Canadian children in an overnight summer camp setting. Here, we present our study design and methodology. In 2019, children between the ages of 7 and 13 took part in the study (n = 126). Children controlled their use of DEET-based insect repellents, and provided an account of their activities at camp that could impact insect repellent absorption. Children provided a total of 389 urine samples throughout the study day, and reported the time that they applied insect repellent, which allowed us to contextualize urinary DEET and metabolite concentrations with respect to the timing of insect repellent application. DEET (2.3%

Noise annoyance toward landscaping equipment was one of nine sources evaluated in the Canadian Perspectives on Environmental Noise Survey, completed online by 6647 Canadian adults. At 6.3% (95% confidence interval = 5.8-6.9), landscaping equipment ranked third after road traffic and construction noise. Stepwise multivariate logistic regression modelled factors associated with annoyance. The perceived impact of the COVID-19 pandemic on outdoor noise annoyance, education level, working/attending school from home, geographic region, province, noise sensitivity, sleep disturbance, duration of residency, and perceived changes in outdoor daytime noise influenced the odds of reporting high annoyance toward landscaping equipment noise over the previous year.

Health Canada, in collaboration with Advanis, conducted the Canadian Perspectives on Environmental Noise Survey (CPENS) to investigate expectations and attitudes toward environmental noise in rural and non-rural Canada. The CPENS, a 26-item questionnaire, was completed online by 6647 randomly selected Canadians, age 18 y and older between April and May 2021. The prevalence of reporting their area as often or always calm, quiet, and relaxing was 76.8%, 64%, and 48.4% in rural/remote, suburban, and urban, respectively. A high expectation of quiet was less prevalent yet followed the same pattern: rural/remote (58.2%), suburban (37.4%), and urban (21.8%). Self-reported health status and noise sensitivity were unrelated to geographic region. A high magnitude of non-specific sleep disturbance over the previous 12 months was reported by 7.8% overall; highest among urban dwellers (9.8%), followed by suburban (7.2%) and rural/remote (5.5%) dwellers (p < 0.01). High annoyance toward road traffic noise was 8.5% overall, and significantly higher in urban (10.5%), relative to suburban (7.9%) and rural/remote (6.6%) areas (p < 0.0001). Annoyance toward noise from rail, aircraft, mining, industry, marine activity, construction, wind turbines, and landscaping equipment is reported. The analysis also explores potential differences between Indigenous Peoples of Canada and non-Indigenous Canadians in their attitudes and expectations toward environmental noise.

Objective: To describe personal listening device (PLD) usage and sociodemographic variables among a nationally representative sample of Canadians and examine audiometric outcomes among a subsample., Design: Audiometry and in-person questionnaires were used to evaluate hearing and PLD usage across age, sex, household income/education level. PLD exposure was quantified using a common occupational noise limit., Study Sample: A randomised sample of 10,460 respondents, aged 6-79, with audiometric analysis of a subsample (n = 4807), aged 6-29, tested between 2012 and 2015., Results: Loud PLD usage was reported by19.5% of Canadians. The highest prevalence was among teenagers (44.2%) and young adults (36.3%). Among children, 13.1% of users listened at loud volumes. High PLD usage (equivalent to or above 85 dBA, LEX 40) among 12-19 year olds was double that of 20-29 year olds: 10.2% versus 5.1% E . Five years or more of loud PLD usage was associated with significantly higher mean hearing thresholds compared to less years. No association between loud or high PLD usage and mean thresholds were found., Conclusion: The majority used PLDs safely, however a small proportion reported high risk usage which will impact hearing should this pattern persist over many years.

Noise-induced stress may precipitate cardiovascular diseases. This research assessed the association between sensorineural bilateral high frequency hearing loss (HFHL), as an indication of excessive noise exposure, and cardiovascular outcomes. Participants (n = 6318, ∼50% male) 20-79 years were recruited through the cross-sectional Canadian Health Measures Survey. Questionnaires included several demographic and health-related variables. Audiometry and blood/urine collection took place in a mobile examination centre. Average thresholds ≥25 dB averaged across 3, 4, and 6 kHz defined HFHL. Logistic or linear regression models explored associations between HFHL and cardiovascular-related risk factors/outcomes. Adjusted models indicated elevated diastolic blood pressure in respondents with normal hearing, X¯ = 72.52 (95% confidence interval: 71.85-73.18) compared to the group with bilateral HFHL, X¯ = 70.28 (95%CI: 69.13-71.43), p < 0.05. Average total cholesterol, high-density lipoprotein, low-density lipoprotein and apolipoprotein A1 were elevated in the normal hearing group (p < 0.05). Insulin, high-sensitivity C-reactive protein, and average resting heart rate were elevated in the group with bilateral HFHL, p < 0.05. A stratified analysis by sex- and age, or history of loud occupational noise exposure, did not change the overall results. Although some findings warrant further exploration, the overall analysis did not provide compelling evidence for an association between HFHL and cardiovascular-related biomarkers, or cardiovascular diseases among Canadians aged 20-79 years.

Self-reported occupational noise exposure has been associated with impaired hearing, but its relationship with extra-auditory affects remains uncertain. This research assessed the association between self-reported occupational noise exposure and cardiovascular outcomes. Participants (n = 6318, ∼50% male) from the Canadian Health Measures Survey (2012-2015) aged 20-79 years were randomly recruited across Canada. An in-person household interview included basic demographics, perceived stress, diagnosed health conditions, and self-reported exposure to a noisy work environment. Direct physiological assessment in a mobile examination centre permitted the determination of biomarkers/risk factors related to cardiovascular function. Logistic or linear regression models explored the association between self-reported occupational noise exposure and several cardiovascular endpoints after adjusting for confounding variables. After adjustments, there was no evidence for an association between occupational noise and any of the evaluated endpoints, which included but were not limited to blood pressure, heart rate, blood glucose, insulin, lipids, diagnosed hypertension, medication for hypertension, myocardial infarction, stroke, or heart disease. There was no evidence that self-reported occupational noise exposure was associated with evaluated cardiovascular-related biomarkers, or cardiovascular diseases among Canadians aged 20-79 years. This study, and others like it, provides an important contribution to an evidence base that could inform policy related to occupational noise exposure.

Subway PM 2.5 can be substantially sourced from the operation of the system itself. Improvements in subway air quality may be possible by examining the potential to reduce these emissions. To this end, PM 2.5 was measured on the trains and station platforms of the Toronto subway system. A comparison with previously published data for this system reveals significant changes in below ground platform PM 2.5 . A reduction of nearly one-third (ratio (95% CI): 0.69 (0.63, 0.75)) in PM 2.5 from 2011 to 2018 appears to have resulted from a complete modernization of the rolling stock on one subway line. In contrast, below ground platform PM 2.5 for another line increased by a factor of 1.48 (95% CI; 1.42, 1.56). This increase may be related to an increase in emergency brake applications, the resolution of which coincided with a large decrease in PM 2.5 concentrations on that line. Finally, platform PM 2.5 in two newly opened stations attained, within one year of operation, typical concentrations of the neighboring platforms installed in 1963. Combined, these findings suggest that the production of platform PM 2.5 is localized and hence largely freshly emitted. Further, PM 2.5 changed across this subway system due to changes in its operation and rolling stock. Thus, similar interventions applied intentionally may prove to be equally effective in reducing PM 2.5 . Moreover, establishing a network of platform PM 2.5 monitors is recommended to monitor ongoing improvements and identify impacts of future system changes on subway air quality. This would result in a better understanding of the relationship between the operations and air quality of subways.

This population-based study estimates the prevalence of loud leisure noise exposure and hearing protection usage among Canadians, as well as the population potentially at-risk using an occupational limit of 85 dBA, LEX 40 h, which denotes a typical occupational noise limit for a 40 hour work week. A total of 10 460 participants, aged 6-79 years, completed a Canadian Health Measures Survey household questionnaire. Loud leisure noise was defined by vocal effort required while communicating at arm's length except for loud personal listening device (PLD) usage with earbuds/headphones, which included both volume setting and vocal effort. The most prevalent loud leisure noise activities were amplified music, car/home stereo listening, and power tools, with 40% reporting each source, followed by sporting/entertainment (25%), gasoline engines (23%), and loud PLD listening (19.5%). Loud leisure noise was more prevalent among 12-39 year olds and males. Hearing protection usage was uncommon, from 44.2% (firearms) to 20.3% (power tools) and below 3% during amplified music and sporting/entertainment events. Calculations using self-reported duration of loud leisure noise activities estimated that 6.6 × 10 6 Canadians were in the high cumulative noise exposure category. A large proportion of Canadians would be expected to develop some degree of noise-induced hearing loss should this pattern persist over years.

Background: Unprotected exposure to handheld lasers can cause temporary or permanent vision loss depending on the laser classification., Objective: To evaluate the occurrence of, and details associated with, reported eye injuries resulting from handheld lasers., Methods: A 14-item questionnaire developed by Health Canada was distributed by the Canadian Ophthalmological Society and the Canadian Association of Optometrists to their respective members., Results: Questionnaire data were available from 909 respondents (263 ophthalmologists; 646 optometrists). Response rates were 23.1% and 12.7%, respectively. Validated data were available from 903 respondents, where 157 (17.4%) reported encountering at least 1 eye injury from a handheld laser. A total of 318 eye injuries were reported with an annual increase of 34.4% (95% CI 21.6%-48.7%, p < 0.0001) between 2013 and 2017. When respondents reported on only their most severe case, 77 (53.5%) reported vision loss that ranged from minor to severe, which persisted for more than 6 months in 42.9% of the cases. Another 59 (41.3%) noted the presence of retinal damage. The prevalence of eye injuries from handheld lasers was higher for males (82.5%) than females (14.0%), more frequent among those under the age of 50 years, and occurred predominately as a result of exposure from another person (67.6%) versus self-induced (26.1%) (p < 0.0001)., Conclusions: Although this pilot study permits insight into the potential prevalence of injuries resulting from exposure to handheld laser devices in Canada, the results are not nationally representative. These findings support additional surveillance activities that may inform risk assessment and potential risk management strategies., (Crown Copyright © 2019. Published by Elsevier Inc. All rights reserved.)

Objectives: Noise emissions from wind turbines are one of multiple wind turbine features capable of generating annoyance that ranges in magnitude from not at all annoyed to extremely annoyed. No analysis to date can simultaneously reflect the change in all magnitudes of annoyance toward multiple wind turbine features. The primary objective in this study was to use principal component analysis (PCA) to provide a single construct for overall annoyance to wind turbines based on reactions to noise, blinking lights, shadow flicker, visual impacts, and vibrations evaluated as a function of proximity to wind turbines., Methods: The analysis was based on data originally collected as part of Health Canada's cross-sectional Community Noise & Health Study (CNHS). One adult participant (18-79 years), randomly selected from dwellings in Ontario (ON) (n = 1011) and Prince Edward Island (PEI) (n = 227), completed an in-person questionnaire. Content relevant to the current analysis included the annoyance responses to wind turbines., Results: The first construct tested in the PCA explained 58-69% of the variability in total annoyance. Reduced distance to turbines was associated with elevated aggregate annoyance scores among ON and PEI participants. In the ON sample, aggregate annoyance was effectively absent in areas beyond 5 km (mean 0.12; 95% CI 0.00, 1.19), increasing significantly between (2 and 5] km (mean 2.13; 95% CI 0.92, 3.33), remaining elevated, but with no further increase until (0.550-1] km (mean 3.37; 95% CI 3.02, 3.72). At ≤ 0.550 km, the average overall annoyance was 3.36 (95% CI 2.03, 4.69). In PEI, aggregate annoyance was essentially absent beyond 1 km; i.e., (1-2] km (mean 0.21; 95% CI 0.00, 0.88); (2-5] km (mean 0.00; 95% CI 0.00, 1.37); > 5 km (mean 0.00; 95% CI 0.00, 1.58). Annoyance significantly increased in areas between (0.550 and 1] km (mean 1.59; 95% CI 1.02, 2.15) and was highest within 550 m (mean 4.25; 95% CI 3.34, 5.16)., Conclusion: The advantages and disadvantages to an aggregated annoyance analysis, including how it should not yet be considered a substitute for relationships based on changes in high annoyance, are discussed.

Objective: An aggregate annoyance construct has been developed to account for annoyance that ranges from not at all annoyed to extremely annoyed, toward multiple wind turbine features. The practical value associated with aggregate annoyance would be strengthened if it was related to health. The objective of the current paper was to assess the association between aggregate annoyance and multiple measures of health., Methods: The analysis was based on data originally collected as part of Health Canada's Community Noise and Health Study (CNHS). One adult participant per dwelling (18-79 years), randomly selected from Ontario (ON) (n = 1011) and Prince Edward Island (PEI) (n = 227), completed an in-person questionnaire., Results: The average aggregate annoyance score for participants who indicated they had a health condition (e.g., chronic pain, Pittsburgh Sleep Quality Index (PSQI) > 5, tinnitus, migraines/headaches, dizziness, highly sensitive to noise, and reported a high sleep disturbance) ranged from 2.53 to 3.72; the mean score for those who did not report these same conditions ranged between 0.96 and 1.41. Household complaints about wind turbine noise had the highest average aggregate annoyance (8.02), compared to an average of 1.39 among those who did not complain., Conclusion: A mean aggregate annoyance score that could reliably distinguish participants who self-report health effects (or noise complaints) from those who do not could be one of several factors considered by jurisdictions responsible for decisions regarding wind turbine developments. However, the threshold value for acceptable changes and/or levels in aggregate annoyance has not yet been established and could be the focus of future research efforts.

Objective and Approach: A study, conducted in Toronto, Canada, between 2009 and 2011, measured the bone lead concentrations of volunteers aged 1-82 years using in vivo x-ray fluorescence (XRF) technology., Main Results: Bone lead levels were lower compared to Ontario in vivo XRF studies from the early 1990s. In adults, the slope of tibia lead content versus age was reduced by 36-56%, i.e. bone lead levels for a given age group were approximately half compared to the same age group 17 years prior. Further, bone lead levels of individuals fell over that time period. In 2010, an average person aged 57 years had a bone lead level approximately 1/3 less than their bone lead level age 40 years in 1993. Using this data, the half-lives of lead in the tibia were estimated as 7-26 years. Tibia lead levels were found to be low in children. The reduction in bone tibia content in children was not significant (p  =  0.07), but using data from additional north eastern US studies, there is evidence that childhood tibia stores are lower than in the 1990s., Significance: In vivo XRF analysis shows that there has been a reduction in the level of lead in bone in Canada over the last two decades. Public health measures have been very successful in reducing ongoing exposure to lead and in reducing bone lead stores.

Background: The developing fetus and pregnant woman can be exposed to a variety of environmental chemicals that may adversely affect their health. Moreover, environmental exposure and risk disparities are associated with different social determinants, including socioeconomic status (SES) and demographic indicators. Our aim was to investigate whether and how maternal concentrations of a large panel of persistent and non-persistent environmental chemicals vary according to sociodemographic and lifestyle characteristics in a large pregnancy and birth cohort., Methods: Data were analyzed from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study, a cohort of pregnant women (N=2001) recruited over four years (2008-2011) in 10 cities across Canada. In all, 1890 urine and 1938 blood samples from the first trimester (1st and 3rd trimester for metals) were analysed and six sociodemographic and lifestyle indicators were assessed: maternal age, household income, parity, smoking status, country of birth and pre-pregnancy body mass index (BMI)., Results: We found these indicators to be significantly associated with many of the chemicals measured in maternal blood and urine. Women born outside Canada had significantly higher concentrations of di-2-ethylhexyl and diethyl phthalate metabolites, higher levels of all metals except cadmium (Cd), as well as higher levels of polychlorinated biphenyls (PCBs) and legacy organochlorine pesticides (OCPs). Nulliparity was associated with higher concentrations of dialkyl phosphates (DAPs), arsenic, dimethylarsinic acid (DMAA), perfluoroalkyl substances (PFASs) and many of the persistent organic pollutants. Smokers had higher levels of bisphenol A, Cd and perfluorohexane sulfonate, while those women who had never smoked had higher levels of triclosan, DMAA, manganese and some OCPs., Conclusion: Our results demonstrated that inequitable distribution of exposure to chemicals among populations within a country can occur. Sociodemographic and lifestyle factors are an important component of a thorough risk assessment as they can impact the degree of exposure and may modify the individual's susceptibility to potential health effects due to differences in lifestyle, cultural diets, and aging., (Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.)

Hypomethylation of DNA repeats has been linked to diseases and cancer predisposition. Human studies suggest that higher blood concentrations of environmental contaminants (EC) correlate with levels of hypomethylation of DNA repeats in blood. The objective of this study was to examine the effect of in utero and/or lactational exposure to EC on the methylation of DNA repeats (LINE-1 and identifier element) in Sprague-Dawley rat pups at birth, at postnatal day (PND) 21, and in adulthood (PND78-86). From gestation day 0 to PND20, dams were exposed to a mixture "M" of polychlorinated biphenyls (PCB), pesticides, and methylmercury (MeHg), at 0.5 or 1 mg/kg/d (0.5M and M). At birth, some control (C) and M litters were cross-fostered to create the following in utero/postnatal exposure groups: C/C, M/C, C/M, M/M. Additional dams received 1.8 ng/kg/d of a mixture of aryl-hydrocarbon receptor (AhR) agonists (non-ortho-PCB, PC-dibenzodioxins, and PC-dibenzofurans) without or with 0.5M (0.5MAhR). Measurements of EC residue levels confirmed differences in their accumulation across treatments, age, and tissues. Although induction of hepatic detoxification enzyme activities (cytochrome P-450) demonstrated biological effects of treatments, the assessment of methylation in DNA repeats by sodium bisulfite pyrosequencing of liver, spleen, and thymus samples revealed no marked treatment-related effects but significant tissue- and age-related methylation differences. Further studies are required to determine whether absence of significant observable treatment effects on methylation of DNA repeats in the rat relate to tissue, strain, or species differences.

The current study was the first to assess stress reactions associated with wind turbine noise (WTN) exposure using self-reported and objective measures. Randomly selected participants, aged 18-79 yr (606 males; 632 females), living between 0.25 and 11.22 km from wind turbines, were exposed to outdoor calculated WTN levels up to 46 dBA (response rate 78.9%). Multiple regression modeling left the great majority (77%-89%) of the variance in perceived stress scale (PSS) scores, hair cortisol concentrations, resting blood pressure, and heart rate unaccounted for, and WTN exposure had no apparent influence on any of these endpoints. PSS scores were positively, but weakly, related to cortisol concentrations and resting heart rate (Pearson r = 0.13 and r = 0.08, respectively). Across WTN categories, modeled mean PSS scores ranged from 13.15 to 13.84 (p = 0.8614). Modeled geometric means for hair cortisol concentrations, resting mean systolic, diastolic blood pressure, and heart rate were 150.54-191.12 ng/g (p = 0.5416), 113.38-116.82 mmHg (p = 0.4990), 67.98-70.34 mmHg (p = 0.5006), and 68.24-70.71 bpm (p = 0.5223), respectively. Irrespective of WTN levels, diastolic blood pressure appeared to be slightly (2.90 mmHg 95% CI: 0.75,5.05) higher among participants highly annoyed by blinking lights on turbines (p = 0.0081). Collectively, the findings do not support an association between exposure to WTN up to 46 dBA and elevated self-reported and objectively defined measures of stress.

The possibility that wind turbine noise (WTN) affects human health remains controversial. The current analysis presents results related to WTN annoyance reported by randomly selected participants (606 males, 632 females), aged 18-79, living between 0.25 and 11.22 km from wind turbines. WTN levels reached 46 dB, and for each 5 dB increase in WTN levels, the odds of reporting to be either very or extremely (i.e., highly) annoyed increased by 2.60 [95% confidence interval: (1.92, 3.58), p < 0.0001]. Multiple regression models had R(2)'s up to 58%, with approximately 9% attributed to WTN level. Variables associated with WTN annoyance included, but were not limited to, other wind turbine-related annoyances, personal benefit, noise sensitivity, physical safety concerns, property ownership, and province. Annoyance was related to several reported measures of health and well-being, although these associations were statistically weak (R(2 )< 9%), independent of WTN levels, and not retained in multiple regression models. The role of community tolerance level as a complement and/or an alternative to multiple regression in predicting the prevalence of WTN annoyance is also provided. The analysis suggests that communities are between 11 and 26 dB less tolerant of WTN than of other transportation noise sources.

The Community Noise and Health Study conducted by Health Canada included randomly selected participants aged 18-79 yrs (606 males, 632 females, response rate 78.9%), living between 0.25 and 11.22 km from operational wind turbines. Annoyance to wind turbine noise (WTN) and other features, including shadow flicker (SF) was assessed. The current analysis reports on the degree to which estimating high annoyance to wind turbine shadow flicker (HAWTSF) was improved when variables known to be related to WTN exposure were also considered. As SF exposure increased [calculated as maximum minutes per day (SFm)], HAWTSF increased from 3.8% at 0 ≤ SFm < 10 to 21.1% at SFm ≥ 30, p < 0.0001. For each unit increase in SFm the odds ratio was 2.02 [95% confidence interval: (1.68,2.43)]. Stepwise regression models for HAWTSF had a predictive strength of up to 53% with 10% attributed to SFm. Variables associated with HAWTSF included, but were not limited to, annoyance to other wind turbine-related features, concern for physical safety, and noise sensitivity. Reported dizziness was also retained in the final model at p = 0.0581. Study findings add to the growing science base in this area and may be helpful in identifying factors associated with community reactions to SF exposure from wind turbines.

Health Canada, in collaboration with Statistics Canada, and other external experts, conducted the Community Noise and Health Study to better understand the impacts of wind turbine noise (WTN) on health and well-being. A cross-sectional epidemiological study was carried out between May and September 2013 in southwestern Ontario and Prince Edward Island on 1238 randomly selected participants (606 males, 632 females) aged 18-79 years, living between 0.25 and 11.22 km from operational wind turbines. Calculated outdoor WTN levels at the dwelling reached 46 dBA. Response rate was 78.9% and did not significantly differ across sample strata. Self-reported health effects (e.g., migraines, tinnitus, dizziness, etc.), sleep disturbance, sleep disorders, quality of life, and perceived stress were not related to WTN levels. Visual and auditory perception of wind turbines as reported by respondents increased significantly with increasing WTN levels as did high annoyance toward several wind turbine features, including the following: noise, blinking lights, shadow flicker, visual impacts, and vibrations. Concern for physical safety and closing bedroom windows to reduce WTN during sleep also increased with increasing WTN levels. Other sample characteristics are discussed in relation to WTN levels. Beyond annoyance, results do not support an association between exposure to WTN up to 46 dBA and the evaluated health-related endpoints.