title: Evidence for the initiation of decompression sickness by exposure to intense underwater sound.
abstract: Mass stranding of cetaceans (whales and dolphins), in close association with the activity of naval sonar systems, has been reported on numerous occasions. Necropsy showed bubble-associated lesions similar to those described in human decompression sickness (DCS). We examined the hypothesis that exposure to underwater sound may potentiate DCS. Rats were subjected to immersion and simulated dives with and without simultaneous acoustic transmissions at pressure levels and frequencies of 204 dB/8 kHz and 183.3 dB/15 kHz. DCS severity was assessed using the rotating wheel method. Recording of somatosensory evoked potentials (SSEPs) was employed under general anesthesia as an electrophysiological measure of neurologic insult. A significantly higher rate of decompression sickness was found among animals exposed to the 204-dB/8-kHz sound field. Significantly higher pathological SSEPs scores were noted for both underwater sound protocols. Pathological SSEPs scores in animals immersed during the acoustic transmissions, but without changes in ambient pressure, were comparable to those observed in animals exposed to the dive profile. The results demonstrate induction of neurological damage by intense underwater sound during immersion, with a further deleterious effect when this was combined with decompression stress. The study outcome has potential implications for human diving safety and may provide an explanation for the mass stranding of cetaceans purportedly associated with sonar activity.
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel;
authors.forename: Dror
authors.initials: D
authors.lastname: Tal
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel;
authors.forename: Hofit
authors.initials: H
authors.lastname: Shachar-Bener
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel; Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel;
authors.forename: Dov
authors.initials: D
authors.lastname: Hershkovitz
authors.affiliation: Israel Naval Medical Institute, Israel Defense Forces Medical Corps, Haifa, Israel;
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Arieli
authors.affiliation: Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel; Unit of Otoneurology, Lin Medical Center, Haifa, Israel; and Department of Otolaryngology Head and Neck Surgery, Carmel Medical Center, Haifa, Israel shupak@012.net.il.
authors.forename: Avi
authors.initials: A
authors.lastname: Shupak
mesh_terms: D000818:Animals; D003665:Decompression Sickness / Q000209:etiology / Q000503:physiopathology*; D004242:Diving / Q000009:adverse effects; D005073:Evoked Potentials, Somatosensory; D008297:Male; D011312:Pressure / Q000009:adverse effects; D011846:Radio Waves / Q000009:adverse effects*; D051381:Rats; D017207:Rats, Sprague-Dawley
keywords: bioeffect; decompression sickness; rectified diffusion; somatosensory evoked potentials; underwater acoustics