Recent Research on EMF and Health Risk, Twelfth report from SSM's Scientific Council on Electromagnetic Fields, 2017

Background: The Swedish Radiation Safety Authority's (SSM) Scientific Council on Electromagnetic Fields monitors current research on potential health risks with a correlation to exposure to electromagnetic fields, and provides the Authority with advice on assessing possible health risks. The Council gives guidance when the Authority must give an opinion on policy matters when scientific testing is necessary. The Council is required to submit a written report each year on the current research and knowledge situation. Objective: The report has the objective of covering the previous year's research in the area of electromagnetic fields (EMF). The report gives the Swedish Radiation Safety Authority an overview and provides an important basis for risk assessment. Results: The present annual report is the twelfth in this series and covers studies published from October 2015 up to and including March 2017. The report covers different areas of EMF (static, low frequency, intermediate, and radio frequency fields) and different types of studies such as biological, human and epidemiological studies. No new health risks have been identified. Whether mobile phone use causes brain tumours or not was mainly addressed using time trends studies in the last two years. The results were not entirely consistent but mainly point towards a lack of association. Some cell and animal studies indicate that EMF exposure may cause oxidative stress even at low exposure levels. It is unclear what relevance this may have when it comes to direct health effects in humans. A striking result was that some studies showed a stronger association between memory functions and radio wave exposure than other usage variables. The annual report also has a section covering other relevant scientific reports published recently

Decline in subarachnoid haemorrhage volumes associated with the first wave of the COVID-19 pandemic

BACKGROUND: During the COVID-19 pandemic, decreased volumes of stroke admissions and mechanical thrombectomy were reported. The study\u27s objective was to examine whether subarachnoid haemorrhage (SAH) hospitalisations and ruptured aneurysm coiling interventions demonstrated similar declines. METHODS: We conducted a cross-sectional, retrospective, observational study across 6 continents, 37 countries and 140 comprehensive stroke centres. Patients with the diagnosis of SAH, aneurysmal SAH, ruptured aneurysm coiling interventions and COVID-19 were identified by prospective aneurysm databases or by International Classification of Diseases, 10th Revision, codes. The 3-month cumulative volume, monthly volumes for SAH hospitalisations and ruptured aneurysm coiling procedures were compared for the period before (1 year and immediately before) and during the pandemic, defined as 1 March-31 May 2020. The prior 1-year control period (1 March-31 May 2019) was obtained to account for seasonal variation. FINDINGS: There was a significant decline in SAH hospitalisations, with 2044 admissions in the 3 months immediately before and 1585 admissions during the pandemic, representing a relative decline of 22.5% (95% CI -24.3% to -20.7%, p\u3c0.0001). Embolisation of ruptured aneurysms declined with 1170-1035 procedures, respectively, representing an 11.5% (95%CI -13.5% to -9.8%, p=0.002) relative drop. Subgroup analysis was noted for aneurysmal SAH hospitalisation decline from 834 to 626 hospitalisations, a 24.9% relative decline (95% CI -28.0% to -22.1%, p\u3c0.0001). A relative increase in ruptured aneurysm coiling was noted in low coiling volume hospitals of 41.1% (95% CI 32.3% to 50.6%, p=0.008) despite a decrease in SAH admissions in this tertile. INTERPRETATION: There was a relative decrease in the volume of SAH hospitalisations, aneurysmal SAH hospitalisations and ruptured aneurysm embolisations during the COVID-19 pandemic. These findings in SAH are consistent with a decrease in other emergencies, such as stroke and myocardial infarction

Lung clearance and retention of toner, TiO2, and crystalline silica, utilizing a tracer technique during chronic inhalation exposure in syrian golden hamsters

Male and female Syrian golden hamsters were exposed 6h/day, 5 days/wk for up to 18 month to a special test toner, TiO2, and crystalline silica. The mass median aerodynamic diameters (MMAD) were about 4.0 mikro m for toner, 1.1 mikro m for TiO2, and 1.4 mikro m for silica. The target test aerosol exposure concentrations during the first 5 mo were 1.5, 6, and 24 mg/m3 (called toner low, toner medium, and toner high) for the test toner, 40 mg/m3 for TiO2, and 3 mg for SiO2. They were changed to 4, 16 and 64 mg/m3 for toner and 30 mg/m3 for TiO2 after 5 mo in order to achieve the desired lung burdens

A novel indicator for evaluation of the impact of distributed generations on the energy losses of low voltage distribution grids

Decentralization of energy generations in power distribution systems is recognized as an important development strategy to incorporate more small-scale renewable sources, reduce greenhouse gas emissions and increase energy efficiency. Beside integrating more decentralized generations into existing systems, an efficient system operation is equally important toward achieving a sustainable energy system. In order to keep track of upcoming changes regarding system efficiency, an accurate determination of energy losses in distribution system is the prominent step. Especially in the distribution systems with high penetration of the renewable energy resources, the installed distributed generations can significantly affect energy losses and influence grid efficiency in power distribution systems. To address this issue, this paper investigates the impact of distributed generations on the annual energy losses in low voltage distribution grids. Based on an analytical study on grid losses and the relevant features, which are used to describe the grid integration of distributed generators in diverse scenarios, an annual energy loss indicator is proposed in this work. This new indicator is capable to estimate the energy losses of low voltage grids for a wide range of scenarios concerning both the installation of distributed generators and grid structures. Also, the formulation of this new indicator is largely simplified in comparison to other state-of-the-art indicators presented by previous studies. The effectiveness and the performance of the proposed methodology is first demonstrated in two typical low voltage grids, in which high amount of photovoltaic units already exist today. Further, this indicator is applied on a set of grids in extended tests on readability and robustness. Comparison of the estimations using the proposed indicator against the exhaustive power flow calculations shows that the proposed indicator gives a reliable and sufficiently accurate estimation of grid energy losses under influences of distributed generations. Fast evaluations of the system losses, enabled by the proposed indicator, provide assessments on energy efficiency of distribution systems in future development stages of distributed generations. Accordingly, distribution system operators are able to select optimal locations for new generation units, adjust their grid reinforcement plans to improve the total energy efficiency on the whole system scales

The carcinogenic potency of carbon particles with and without PAH after repeated intratracheal administration in the rat

The role of carcinogenic PAH in soot- and carbon black-related lung tumour induction in rats was investigated after intratracheal administration of carbon blacks (CB) and two types of diesel soot (DS) either as original or as toluene extracted particles. The total particle dose per animal was 15 mg subdivided into 16-17 weekly applications. There was one vehicle control and two groups were treated with a total dose of either 30 or 15 mg pure BaP as positive control. The main tumour results were: (a) original DS induced a higher tumour rate than extracted DS; (b) the carcinogenic potency of extracted CB probably depends on the size of the primary carbon particles and on the specific surface area of the particles; (c) extracted DS covered with 11 micrograms BaP per mg carbon particles caused a lower lung tumour rate than original DS containing only 0,9 mg BaP per mg, but a variety of other PAH and N02-PAH; (d) a total dose of 15 mg pure BaP caused a lung tumour (abstract truncated

A pilot study on the refinement of acute inhalation toxicity studies: The isolated perfused rat lung as a screening tool for surface-active substances

New surface-active agents in waterproofing sprays are frequently tested for acute inhalation toxicity in vivo according to OECD Test Guideline 403. In order to refine and reduce the number of acute inhalation tests performed, we propose a screening test that uses isolated lungs. The test consists of the exposure of isolated, ventilated and perfused rat lungs, to aerosolised formulations of waterproofing agents (mass median aerodynamic diameter = 1 mu m), and on-line monitoring of respiratory parameters and gross pathology analysis. A pilot evaluation of the isolated perfused rat lung model for use in a screening test was carried out by blind testing 12 surface-active substances. The results obtained compared well with data available from in vivo acute inhalation studies. Substances that triggered harmful effects, such as impaired lung compliance and atelectasis of the isolated perfused lung, were also found to cause changes in respiratory parameters, some of which would be severe enough to lead to death in in vivo tests with rats. The changes in respiratory parameters suggest that the mode-of-action is associated with impairment of the surfactant layer. Therefore, pre-testing in the isolated perfused rat lung allows the identification of surface-active substances with the potential for causing acute inhalation toxicity

Ultrastructural observations in mouse lungs after short term inhalation of cadmium compounds

Chronic environmental or workplace inhalation exposure to Cadmiun (Cd) compounds causes lung cancer, but the effects of acute Cd inhalation are not known. In this study, the acute morphological changes due to short term Cd exposure in lung were investigated by light and transmission electron microscopy. Acute Cd inhalation causes severe lung damage in mice which partly persists after a clean air recovery period. Different Cd compounds evoke different types of morphological changes, Cd oxide causing the earliest and most severe tissue damage