Transcriptome analysis in mouse skin after exposure to ultraviolet radiation from a canopy sunbed.

Exposure to ultraviolet radiation (UV-R), from both natural and artificial tanning, heightens the risk of skin cancer by inducing molecular changes in cells and tissues. Despite established transcriptional alterations at a molecular level due to UV-R exposure, uncertainties persist regarding UV radiation characterization and subsequent genomic changes. Our study aimed to mechanistically explore dose- and time-dependent gene expression changes, that may drive short-term (e.g., sunburn) and long-term actinic (e.g., skin cancer) consequences. Using C57BL/6N mouse skin, we analyzed transcriptomic expression following exposure to five erythemally weighted UV-R doses (0, 5, 10, 20, and 40 mJ/cm2 ) emitted by a UV-R tanning device. At 96 h post-exposure, 5 mJ/cm2 induced 116 statistically significant differentially expressed genes (DEGs) associated with structural changes from UV-R damage. The highest number of significant gene expression changes occurred at 6 and 48 h post-exposure in the 20 and 40 mJ/cm2 dose groups. Notably, at 40 mJ/cm2 , 13 DEGs related to skin barrier homeostasis were consistently perturbed across all timepoints. UV-R exposure activated pathways involving oxidative stress, P53 signaling, inflammation, biotransformation, skin barrier maintenance, and innate immunity. This in vivo study's transcriptional data offers mechanistic insights into both short-term and potential non-threshold-dependent long-term health effects of UV-R tanning.

Effects of Radiofrequency Electromagnetic Field (RF-EMF) exposure on pregnancy and birth outcomes: A systematic review of experimental studies on non-human mammals.

BACKGROUND: The World Health Organization is coordinating an international project aimed at systematically reviewing the evidence regarding the association between radiofrequency electromagnetic field (RF-EMF) exposure and adverse health effects. Within the project, 6 topics have been prioritized by an expert group, which include reproductive health outcomes. OBJECTIVES: According to the protocol published in 2021, a systematic review and meta-analyses on the adverse effects of RF-EMF exposure during pregnancy in offspring of experimental animals were conducted. METHODS: Three electronic databases (PubMed, Scopus and EMF Portal) were last searched on September 8 or 17, 2022. Based on predefined selection criteria, the obtained references were screened by two independent reviewers. Studies were included if they met the following criteria: 1) original, sham controlled experimental study on non-human mammals exposed in utero, published in peer-reviewed journals, 2) the experimental RF-EMF exposure was within the frequency range 100 kHz-300 GHz, 3) the effects of RF-EMF exposure on fecundity (litter size, embryonic/fetal losses), on the offspring health at birth (decrease of weight or length, congenital malformations, changes of sex ratio) or on delayed effects (neurocognitive alterations, female infertility or early-onset cancer) were studied. Study characteristics and outcome data were extracted by two reviewers. Risk of bias (RoB) was assessed using the Office of Health Assessment and Translation (OHAT) guidelines. Study results were pooled in a random effects meta-analysis comparing average exposure to no-exposure and in a dose-response meta-analysis using all exposure doses, after exclusion of studies that were rated at "high concern" for RoB. Subgroup analyses were conducted for species, Specific Absorption Rate (SAR) and temperature increase. The certainty of the evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach. RESULTS: Eighty-eight papers could be included in this review. Effects on fecundity. The meta-analysis of studies on litter size, conducted at a whole-body average SAR of 4.92 W/kg, did not show an effect of RF-EMF exposure (MD 0.05; 95% CI -0.21 to 0.30). The meta-analysis of studies on resorbed and dead fetuses, conducted at a whole-body average SAR of 20.26 W/kg, showed a significant increase of the incidence in RF-EMF exposed animals (OR 1.84; 95% CI 1.27 to 2.66). The results were similar in the dose-response analysis. Effects on the offspring health at birth. The meta-analysis of studies on fetal weight, conducted at a whole-body average SAR of 9.83 W/kg, showed a small decrease in RF-EMF exposed animals (SMD 0.31; 95% CI 0.15 to 0.48). The meta-analysis of studies on fetal length, conducted at a whole-body average SAR of 4.55 W/kg, showed a moderate decrease in length at birth (SMD 0.45; 95% CI 0.07 to 0.83). The meta-analysis of studies on the percentage of fetuses with malformations, conducted at a whole-body average SAR of 6.75 W/kg, showed a moderate increase in RF-EMF exposed animals (SMD -0.45; 95% CI -0.68 to -0.23). The meta-analysis of studies on the incidence of litters with malformed fetuses, conducted at a whole-body average SAR of 16.63 W/kg, showed a statistically significant detrimental RF-EMF effect (OR 3.22; 95% CI 1.9 to 5.46). The results were similar in the dose-response analyses. Delayed effects on the offspring health. RF-EMF exposure was not associated with detrimental effects on brain weight (SMD 0.10; 95% CI -0.09 to 0.29) and on learning and memory functions (SMD -0.54; 95% CI -1.24 to 0.17). RF-EMF exposure was associated with a large detrimental effect on motor activity functions (SMD 0.79; 95% CI 0.21 to 1.38) and a moderate detrimental effect on motor and sensory functions (SMD -0.66; 95% CI -1.18 to -0.14). RF-EMF exposure was not associated with a decrease of the size of litters conceived by F2 female offspring (SMD 0.08; 95% CI -0.39 to 0.55). Notably, meta-analyses of neurobehavioural effects were based on few studies, which suffered of lack of independent replication deriving from only few laboratories. DISCUSSION: There was high certainty in the evidence for a lack of association of RF-EMF exposure with litter size. We attributed a moderate certainty to the evidence of a small detrimental effect on fetal weight. We also attributed a moderate certainty to the evidence of a lack of delayed effects on the offspring brain weight. For most of the other endpoints assessed by the meta-analyses, detrimental RF-EMF effects were shown, however the evidence was attributed a low or very low certainty. The body of evidence had limitations that did not allow an assessment of whether RF-EMF may affect pregnancy outcomes at exposure levels below those eliciting a well-known adverse heating impact. In conclusion, in utero RF-EMF exposure does not have a detrimental effect on fecundity and likely affects offspring health at birth, based on the meta-analysis of studies in experimental mammals on litter size and fetal weight, respectively. Regarding possible delayed effects of in utero exposure, RF-EMF probably does not affect offspring brain weight and may not decrease female offspring fertility; on the other hand, RF-EMF may have a detrimental impact on neurobehavioural functions, varying in magnitude for different endpoints, but these last findings are very uncertain. Further research is needed on the effects at birth and delayed effects with sample sizes adequate for detecting a small effect. Future studies should use standardized endpoints for testing prenatal developmental toxicity and developmental neurotoxicity (OECD TG 414 and 426), improve the description of the exposure system design and exposure conditions, conduct appropriate dosimetry characterization, blind endpoint analysis and include several exposure levels to better enable the assessment of a dose-response relationship. PROTOCOL REGISTRATION AND PUBLICATION: The protocol was published in Pacchierotti et al., 2021 and registered in PROSPERO CRD42021227746 (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=227746).

Hair cortisol as a viable tool for the assessment of an association between environmental noise exposure and chronic stress.

Entrenched in the well-established link between stress and health, noise exposure as a potential contributor to stress-related health effects receives tremendous attention. Indeed, exposure to noise can act as a stressor as evidenced through increased heart rate, blood pressure, adrenaline, epinephrine, and cortisol. Cortisol is secreted from the adrenal glands in response to stressor-induced activation of the hypothalamic-pituitary-adrenal axis. For assessment of environmental noise and stress, repeated sampling in blood, saliva, or urine is necessary to evaluate the association between environmental noise exposure and protracted changes in cortisol. Controlling for the many variables that influence the secretion of cortisol at discrete sampling intervals is challenging. Studies suggest that systemically produced cortisol integrates and remains in hair as it grows, providing a measure that integrates a cortisol response over a longer period, circumventing several limitations associated with multiple sampling. Robust evidence supports the integration of cortisol into hair, yet recent studies call into question the notion that cortisol is retained with growth. The current paper discusses the strengths and limitations of hair cortisol analysis with an emphasis on its utility as a measure of chronic stress in environmental noise studies.

Implications of the COVID-19 pandemic on self-reported health status and noise annoyance in rural and non-rural Canada.

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.

A comparison of self-reported health status and perceptual responses toward environmental noise in rural, suburban, and urban regions in Canada.

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.

Effects of radiofrequency electromagnetic fields (RF EMF) on cancer in laboratory animal studies.

BACKGROUND: The carcinogenicity of radiofrequency electromagnetic fields (RF EMF) has been evaluated by the International Agency for Research on Cancer (IARC) in 2011. Based on limited evidence of carcinogenicity in humans and in animals, RF EMF were classified as possibly carcinogenic to humans (Group 2B). In 2018, based on a survey amongst RF experts, WHO prioritized six major topics of potential RF EMF related human health effects for systematic reviews. In the current manuscript, we present the protocol for the systematic review of experimental laboratory animal studies (cancer bioassays) on exposure to RF fields on the outcome of cancer in laboratory animals. OBJECTIVE: In the framework of WHO's Radiation Program, the aim of this work is to systematically evaluate effects of RF EMF exposure on cancer in laboratory animals. STUDY ELIGIBILITY AND CRITERIA: WHO's Handbook (2014) for guideline development will be followed with appropriate adaptation. The selection of eligible studies will be based on Population, Exposures, Comparators, and Outcomes (PECO) criteria. We will include peer-reviewed articles and publicly available reports from government agencies reporting original data about animal cancer bioassays on exposure to RF EMF. The studies are identified by searching the following databases: MEDLINE (PubMed), Science Citation Index Expanded and Emerging Sources Citation Indes (Web of Science), Scopus, and the EMF Portal. No language or year-of-publication restrictions are applied. The methods and results of eligible studies will be presented in accordance with the PRISMA 2020 guidelines. STUDY APPRAISAL METHOD: Study evaluation of individual studies will be assessed using a risk of bias (RoB) tool developed by the Office of Health Assessment and Translation (OHAT) with appropriate considerations including sensitivity for evaluating RF EMF exposure in animal cancer bioassays. The final evaluation on the certainty of the evidence on a carcinogenic risk of RF EMF exposure in experimental animals will be performed using the OHAT Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach with appropriate considerations. The protocol has been registered in an open-source repository (PROSPERO). FUNDING: The study is partly financially supported by the World Health Organization. No additional funding was provided outside author salaries through their places of employment.

Annoyance toward landscaping equipment noise in Canada.

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.

Self-reported occupational noise exposure and cardiovascular disease in Canada: Results from the Canadian Health Measures Survey.

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.

High frequency hearing impairment and cardiovascular disease in Canada: Results from the Canadian Health Measures Survey.

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.

Prevalence of handheld laser device use, exposure and associated injury.

BACKGROUND: This study assessed the use of and exposure to handheld laser devices by Canadians and the potential associated health risks. DATA AND METHODS: The 2019 Canadian Community Health Survey collected data from 12,397 Canadians on the prevalence of handheld laser exposure or use, and associated eye or skin injuries. RESULTS: In 2019, an estimated 12.4% (95% CI: 11.4% to 13.4%) of Canadians reported using a handheld laser device or being exposed to its beam in the previous year, and those between the ages of 12 and 17 represented 30.5% (95% CI: 26.6% to 34.4%) of users. The highest laser device use or exposure was among those with a university education (13.8%; 95% CI: 11.8% to 15.8%), and a significant trend was found over income categories (p < 0.0001). The highest prevalence of exposure or use involved laser pointers (69.4%; 95% CI: 65.4% to 73.4%), followed by laser toys (38.5%; 95% CI: 34.6% to 42.5%), laser torches (8.2%; 95% CI: 6.1% to 10.4%) and-lastly-search-and-rescue lasers (0.8%E; 95% CI: 0.3% to 1.2%). Overall, 0.7%E (95% CI: 0.2% to 1.2%) of Canadians reported discomfort or injury in the past 12 months. One-quarter (27.9%; 95% CI: 23.8% to 31.9%) of users had a laser beam intentionally directed toward their eyes or skin. Most users did not buy the device (56.3%; 95% CI: 52.1% to 60.5%), while 40.5% (95% CI: 36.2% to 44.7%) purchased it at a Canadian retail store or online (3.8%E; 95% CI: 2.6% to 5.0%). DISCUSSION: The prevalence of handheld laser device use and beam exposure was 12.4% (95% CI: 11.4% to 13.4%), representing approximately 3.9 million Canadians. While the number of reported injuries was low, ongoing surveillance helps assess the effectiveness of current risk management approaches for laser products.

Effects of Radiofrequency Electromagnetic Field (RF-EMF) exposure on male fertility and pregnancy and birth outcomes: Protocols for a systematic review of experimental studies in non-human mammals and in human sperm exposed in vitro.

BACKGROUND: Radiofrequency Electromagnetic Fields (RF-EMF) at environmental level have been reported to induce adverse effects on the male reproductive system and developing embryos. However, despite the number of experiments conducted since the 1970s, the diversity of testing approaches and exposure conditions, inconsistencies among results, and dosimetric flaws have not yet permitted a solid assessment of the relationship between RF-EMF exposure and such effects, warranting a more systematic and methodologically rigorous approach to the evaluation of available data. OBJECTIVES: This study aims at evaluating the effects of RF-EMF exposure on male fertility and pregnancy outcomes by a systematic review (SR) of experimental studies, conducted in compliance with international guidelines. The evidence will be organized into three streams: 1) Studies evaluating the impact of RF-EMF on the male reproductive system of experimental mammals; 2) studies evaluating the impact of RF-EMF on human sperm exposed in vitro; 3) studies evaluating the impact of RF-EMF on adverse pregnancy, birth outcomes and delayed effects in experimental mammals exposed in utero. STUDY ELIGIBILITY AND CRITERIA: Eligible studies will include peer-reviewed articles reporting of original results about effects of controlled exposures to RF-EMF in the frequency range 100 kHz-300 GHz on the selected outcomes without any language or year-of-publication restrictions. Eligible studies will be retrieved by calibrated search strings applied to three electronic databases, PubMed, Scopus and EMF Portal and by manual search of the list of references of included papers and published reviews. STUDY APPRAISAL AND SYNTHESIS METHOD: The internal validity of the studies will be evaluated using the Risk of Bias (RoB) Rating Tool developed by National Toxicology Program/Office of Health Assessment and Translation (NTP/OHAT) integrated with input from the SYRCLE RoB tool. Given sufficient commensurate data, meta-analyses will be performed, otherwise narrative syntheses will be produced. Finally, the certainty of the effects of RF-EMF exposure on male fertility and pregnancy and birth outcomes will be established following GRADE. FUNDING: The study is financially supported by the World Health Organization. REGISTRATION: OSF Registration DOI https://doi.org/10.17605/OSF.IO/7MUS3; PROSPERO CRD42021227729, CRD42021227746.

Effects of 1800 MHz radiofrequency fields on signal transduction and antioxidant proteins in human A172 glioblastoma cells.

PURPOSE: To assess the effects of 1800 MHz radiofrequency electromagnetic field (RF-EMF) exposure on the expression of signal transduction and antioxidant proteins in a human-derived A172 glioblastoma cell line. MATERIALS AND METHODS: Adherent human-derived A172 glioblastoma cells (1.0 × 105 cells per 35 mm culture dish, containing 2 mL DMEM media) were exposed to 1800 MHz continuous-wave (CW) or GSM-modulated RF fields, in the presence or absence of serum for 5, 30 or 240 min at a specific absorption rate (SAR) of 0 (sham) or 2.0 W/kg. Concurrent negative (vehicle) and positive controls (1 µg/mL anisomycin) were included in each experiment. Cell lysates were collected immediately after exposure, stabilized by protease and phosphatase inhibitors in lysis buffer, then frozen and maintained at -80 °C until analysis. The relative expression levels of phosphorylated- and total-signal transduction proteins (CREB, JNK, NF-κB, ERK1/2, Akt, p70S6K, STAT3 and STAT5) and antioxidant proteins (SOD1, SOD2, CAT, TRX1, PRX2) were assessed using Milliplex magnetic bead array panels and a MagPix Multiplex imaging system. RESULTS: In cells exposed to 1800 MHz continuous-wave RF-EMF with the presence of serum in the culture medium, CAT expression was statistically significantly decreased after a 30 min exposure, total JNK was decreased at both 30 and 240 min of exposure, STAT3 was decreased after 240 min of exposure and phosphorylated-CREB expression was decreased after 30 min of exposure. In cells exposed to 1800 MHz GSM-modulated RF-EMF in serum-free cultures, the expression level of total STAT5 was decreased after 30 and 240 min of exposure. These observed changes were detected sporadically across time-points, culture conditions and RF-EMF exposure conditions indicating the likelihood of false positive events. When cells were treated with anisomycin for 15 min as a positive control, dramatic increases in the expression of phosphorylated signaling proteins were observed in both serum-starved and serum-fed A172 cells, with larger fold change increases in the serum-free cultures. No statistically significant differences in the expression levels of SOD1, SOD2 or TRX1 were observed under any tested conditions after exposure to RF-EMF. CONCLUSIONS: The current study found no consistent evidence of changes in the expression of antioxidant proteins (SOD1, SOD2, CAT or TRX2) or a variety of signal transductions proteins (CREB, JNK, NF-κB, ERK1/2, Akt, p70S6K, STAT3, STAT5) in a human-derived glioblastoma A172 cell line in response to exposure to 1800 MHz continuous-wave or GSM-modulated RF-EMF for 5, 30 or 240 min in either serum-free or serum-containing cultures.

Prevalence of tanning equipment use among Canadians.

The objective of this study was to collect prevalence estimates of indoor tanning usage and associated injuries in Canada. The rapid response component of the 2019 Canadian Community Health Survey collected data on the use of tanning equipment in the previous 12 months, including reasons for use, frequency/duration of use, precautions taken and adverse reactions or injuries. The 2019 research findings were as follows, an estimated 3.0% (95% CI: 2.5-3.4%) of Canadians reported that they had used indoor tanning equipment in the past year. Among users, 71.1% (95% CI: 63.9-78.3%) were female and females aged 18-34 were significantly more prevalent users compared to females aged 45 or older. The prevalence of indoor tanning was higher among people without a university degree; however, there were no differences in prevalence by household income or region. Most users indicated they used indoor tanning equipment within a tanning salon (75.3%: 95% CI: 69.1-81.6%) and the most common reason for usage was to develop a "protective" base tan (72.1%: 95% CI: 65.2-78.9%). Over one third (39.2%: 95% CI: 31.1-47.2%) of all users reported 10 or more sessions in the past year. The prevalence of indoor UV tanning usage is declining in Canada. Similar to results in 2014, the majority of users continue to be female, with a large number in the 18 to 34 age group.

Sleep actigraphy time-synchronized with wind turbine output.

Studies have yielded inconsistent evidence for an association between long-term average wind turbine sound pressure level (SPL) and disturbed sleep. Transient changes in sleep may be more susceptible to short-term variations in wind turbine SPL throughout the sleep period time. We analyzed sleep actigraphy data (participant sleep nights = 2,094, males = 151, females = 192) in 10 min intervals time-synchronized to wind turbine supervisory control and data acquisition. Calculated indoor wind turbine SPL was considered after adjusting for turbine rotor speed and closed/open bedroom windows. Maximum calculated nightly average wind turbine SPL reached 44.7 dBA (mean = 32.9, SD = 6.4) outdoors and 31.4 dBA (mean = 12.5, SD = 8.3) indoors. Wind turbine SPL in 10 min intervals, and nightly averages, was not statistically associated with actigraphy outcomes. However, the variability in wind turbine SPL due to changes in wind turbine operation across the sleep period time, as measured by the difference between the 10 min SPL and the nightly average SPL (∆SPL), was statistically related to awakenings (p = 0.028) and motility (p = 0.015) rates. These diminutive differences translate to less than 1 min of additional awake and motility time for a 5 dBA increase over a 450 min sleep period time. Overall results showed that wind turbine SPL below 45 dBA was not associated with any consequential changes in actigraphy-measured sleep. Observations based on ∆SPL provided some indication that a more sensitive assessment of sleep may be one that considers variations in wind turbine SPL throughout the sleep period time.

Survey of reported eye injuries from handheld laser devices in Canada.

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.

The application of transcriptional benchmark dose modeling for deriving thresholds of effects associated with solar-simulated ultraviolet radiation exposure.

Considerable data has been generated to elucidate the transcriptional response of cells to ultraviolet radiation (UVR) exposure providing a mechanistic understanding of UVR-induced cellular responses. However, using these data to support standards development has been challenging. In this study, we apply benchmark dose (BMD) modeling of transcriptional data to derive thresholds of gene responsiveness following exposure to solar-simulated UVR. Human epidermal keratinocytes were exposed to three doses (10, 20, 150 kJ/m2 ) of solar simulated UVR and assessed for gene expression changes 6 and 24 hr postexposure. The dose-response curves for genes with p-fit values (≥ 0.1) were used to derive BMD values for genes and pathways. Gene BMDs were bi-modally distributed, with a peak at ∼16 kJ/m2 and ∼108 kJ/m2 UVR exposure. Genes/pathways within Mode 1 were involved in cell signaling and DNA damage response, while genes/pathways in the higher Mode 2 were associated with immune response and cancer development. The median value of each Mode coincides with the current human exposure limits for UVR and for the minimal erythemal dose, respectively. Such concordance implies that the use of transcriptional BMD data may represent a promising new approach for deriving thresholds of actinic effects. Environ. Mol. Mutagen. 59:502-515, 2018. © 2018 The Authors Environmental and Molecular Mutagenesis published by Wiley Periodicals, Inc. on behalf of Environmental Mutagen Society.

Chronic noise exposure in the spontaneously hypertensive rat.

INTRODUCTION: Epidemiological studies have suggested an association between the relative risk for developing cardiovascular disease (CVD) and long-term exposure to elevated levels of transportation noise. The contention is that this association is largely owing to an increase in stress-related biomarkers that are thought to be associated with CVD. Animal models have demonstrated that acute noise exposure is capable of triggering a stress response; however, similar studies using chronic noise models are less common. MATERIALS AND METHODS: The current study assessed the effects of intermittent daily exposure to broadband 80 kHz bandwidth noise of 87.3 dBA for a period of 21 consecutive days in spontaneously hypertensive rats. RESULTS: Twenty-one days of exposure to noise significantly reduced body weight relative to the sham and unhandled control groups; however, noise had no statistically significant impact on plasma adrenocorticotropic hormone (or adrenal gland weights). Noise was associated with a significant, albeit modest, increase in both corticosterone and aldosterone concentrations following the 21 days of exposure. Interleukin 1 and interleukin 6 levels were unchanged in the noise group, whereas both tumour necrosis factor alpha and C-reactive protein were significantly reduced in noise exposed rats. Tail blood sampling for corticosterone throughout the exposure period showed no appreciable difference between the noise and sham exposed animals, largely due to the sizeable variation for each group as well as the observed fluctuations over time. DISCUSSION: The current pilot study provides only modest support that chronic noise may promote stress-related biological and/or developmental effects. More research is required to verify the current findings and resolve some of the unexpected observations.

Transcriptional benchmark dose modeling: Exploring how advances in chemical risk assessment may be applied to the radiation field.

Recent advances in "-omics" technologies have simplified capacity to concurrently assess expression profiles of thousands of targets in a cellular system. However, compilation and analysis of "omics" data in support of human health protection remains a challenge. Benchmark dose (BMD) modeling is currently being employed in chemical risk assessment to estimate acceptable levels of exposure. Although typically applied to conventional endpoints, newer software has enabled this application to be extended to transcriptomic datasets. BMD analytical tools now have the capacity to model transcriptional dose-response data to derive meaningful BMD values for genes, pathways and gene ontologies. In this report, radiation data obtained from the Gene Expression Omnibus (GEO) were analyzed to generate BMD values for transcriptional responses. The datasets comprised microarray analyses of human blood gamma-irradiated ex vivo (0-20 Gy) and human-derived cell lines exposed to alpha particle radiation (0.5-1.5 Gy). The distributions of BMDs for statistically significant genes and pathways in response to radiation exposure were examined and compared across studies. BMD modeling could identify pathway/gene sensitivities across wide radiation dose ranges, experimental conditions (time-points, cell types) and radiation qualities. BMD analysis offered a new approach to examine transcriptional data. The results were shown to provide information on transcriptional thresholds of effects to support refined risk assessments for low dose ionizing radiation exposures, derive gene-based values for relative biological effectiveness and identify pathways involved in radiation sensitivities across cell types which may extend to applications a clinical setting. Environ. Mol. Mutagen. 57:589-604, 2016. © 2016 Wiley Periodicals, Inc.

Analysis of gene expression in mouse brain regions after exposure to 1.9 GHz radiofrequency fields.

PURPOSE: To assess 1.9 GHz radiofrequency (RF) field exposure on gene expression within a variety of discrete mouse brain regions using whole genome microarray analysis. MATERIALS AND METHODS: Adult male C57BL/6 mice were exposed to 1.9 GHz pulse-modulated or continuous-wave RF fields for 4 h/day for 5 consecutive days at whole body average (WBA) specific absorption rates of 0 (sham), ∼0.2 W/kg and ∼1.4 W/kg. Total RNA was isolated from the auditory cortex, amygdala, caudate, cerebellum, hippocampus, hypothalamus, and medial prefrontal cortex and differential gene expression was assessed using Illumina MouseWG-6 (v2) BeadChip arrays. Validation of potentially responding genes was conducted by RT-PCR. RESULTS: When analysis of gene expression was conducted within individual brain regions when controlling the false discovery rate (FDR), no differentially expressed genes were identified relative to the sham control. However, it must be noted that most fold changes among groups were observed to be less than 1.5-fold and this study had limited ability to detect such small changes. While some genes were differentially expressed without correction for multiple-comparisons testing, no consistent pattern of response was observed among different RF-exposure levels or among different RF-modulations. CONCLUSIONS: The current study provides the most comprehensive analysis of potential gene expression changes in the rodent brain in response to RF field exposure conducted to date. Within the exposure conditions and limitations of this study, no convincing evidence of consistent changes in gene expression was found in response to 1.9 GHz RF field exposure.

Cylindrical waveguide electromagnetic exposure system for biological studies with unrestrained mice at 1.9 GHz.

This paper presents the development of an in vivo exposure system for exposing small rodents. The system consists of four identical cylindrical waveguide chambers, each with a plastic cage for housing the animal. The chamber is fed by circularly polarized radiofrequency power in the 1.9 GHz cellular frequency band and is vertically mounted so that the long axis of the animal is co-planar with the rotating incident electric field. Power sensors were used along with directional or hybrid couplers and a digital voltmeter for data acquisition for real-time dose rate monitoring. The system was tested to evaluate its dose rate performance when a mouse phantom or a mouse cadaver was inside the cage. The dose rate was quantified in terms of whole-body-average (WBA) specific absorption rate (SAR) per input power using both measurement and computational methods. The exposures of the mouse phantom and cadaver were evaluated for various possible postures and positions. The measurement results showed that the highest WBA-SAR was 16.9 W kg per 1 W incident power when the cadaver was lying prone against the cage wall and the lowest WBA-SAR was 10.4 W kg per 1 W incident power when the cadaver was standing upright in the cage center. These results were found to be in good agreement with those obtained from the computational method.