{"id":"HHS-OASH-2026-0397-1961","number":"1961","name":"P G","organization":"","posted":"2026-10-09T04:00Z","received":"2026-10-08T04:00Z","body":"See attached file(s)\nPermeability of the Blood-Brain Barrier Induced by 91 5 MHz\nElectromagnetic Radiation, Continuous Wave and Modulated\nat 8, 16, 50, and 200 Hz\n\nABSTRACT Biological effects of electromagnetic fields (EMF) on the blood-brain barrier (BBB)\ncan be studied in sensitive and specific models. In a previous investigation of the permeability of the\nblood-brain barrier after exposure to the various EMF-components of proton magnetic resonance\nimaging (MRI), we found that the exposure to MRI induced leakage of Evans Blue labeled proteins\nnormally not passing the BBB of rats [Salford et al. (1992), in: Resonance Phenomena in Biology,\nOxford University Press, pp. 87-911.\nIn the present investigation we exposed male and female Fischer 344 rats in a transverse elec-\ntromagnetic transmission line chamber to microwaves of 915 MHz as continuous wave (CW) and\npulse-modulated with repetition rates of 8,16, 50, and 200 s-’. The specific energy absorption rate\n(SAR) varied between 0.016 and 5 Wlkg.\nThe rats were not anesthetized during the 2-hour exposure. All animals were sacrificed by\nperfusion-fixation of the brains under chloral hydrate anesthesia about 1 hour after the exposure.\nThe brains were perfused with saline for 3-4 minutes, and thereafter fixed in 4% formaldehyde for\n5-6 minutes. Central coronal sections of the brains were dehydrated and embedded in paraffin and\nsectioned at 5 pm. Albumin and fibrinogen were demonstrated immunohistochemically.\nThe results show albumin leakage in 5 of 62 of the controls and in 56 of 184 of the animals\nexposed to 915 MHz microwaves. Continuous wave resulted in 14 positive findings of 35, which\ndiffer significantly from the controls (P = 0.002). With pulsed 915 MHz microwaves with repetition\nrates of 200,50, 16, and 8 s-l, 42 of 149 were positive, which is highly significant at the P = 0.001\nlevel. This reveals that both CW and pulsed 915 MHz microwaves have the potential to open up the\nBBB for albumin passage. However, there is no significant difference between continuous and\npulsed 915 MHz microwaves in this respect.\nThe frequency of occurrence of extravasates (26%) was found to be independent of SAR for SAR\n< 2.5 W/kg, but rose significantly for the higher SAR values (to 43%).\nThe question of whether the opening of the blood-brain barrier constitutes a health hazard\ndemands further investigation. ","attachments":["https://downloads.regulations.gov/HHS-OASH-2026-0397-1961/attachment_1.pdf"],"attachment_inventory":true,"withheld":false,"source":"https://www.regulations.gov/comment/HHS-OASH-2026-0397-1961","tags":["health-experiences"],"source_hash":"d857d3b4677aebe057f2edce979df7ac932cee6b8df3732c275bc33b644f1965","slug":"health-experiences-comment-1961","classification":{"id":"HHS-OASH-2026-0397-1961","body_sha256":"9a057ac316f748e3d14be8eef1545cc14b740c87dd53eee698cf43999fd5f21d","status":"ai_reviewed","primary_topic":"research","topics":[{"id":"research","evidence":"led proteins\nnormally not passing the BBB of rats [Salford et al. (1992), in: Resonance Phenomena in Bio"},{"id":"neurological","evidence":"fects of electromagnetic fields (EMF) on the blood-brain barrier (BBB)\ncan be studied in sensitive and specific models."},{"id":"mechanisms","evidence":"ated immunohistochemically.\nThe results show albumin leakage in 5 of 62 of the controls and in 56 of 184 of"}],"summary":"Provides an experimental abstract reporting albumin leakage across the blood-brain barrier in exposed rats and calling for further assessment of health implications.","reviewed_at":"2026-10-10T00:02:05Z","review_method":"Complete published comment-body review; identical previously reviewed bodies reused with separate official IDs preserved. Attachments and external links not reviewed.","review_source_sha256":"5775c422c427e7905e603e6c401462369c6c39e2661db206198087c106ac3ef3","source_url":"https://rfsafe.net/hhs-comments/data/catalog.json","scope":"Original comment body; attachments excluded"},"forum_topics":["research","neurological","mechanisms"],"primary_topic":"research","forum_title":"Provides an experimental abstract reporting albumin leakage across the blood-brain barrier in exposed rat…"}