{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,25]],"date-time":"2026-01-25T11:32:24Z","timestamp":1769340744356,"version":"3.49.0"},"reference-count":39,"publisher":"Oxford University Press (OUP)","issue":"1","license":[{"start":{"date-parts":[[2025,11,20]],"date-time":"2025-11-20T00:00:00Z","timestamp":1763596800000},"content-version":"vor","delay-in-days":323,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2025,1,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Objectives: A simple method to evaluate clinically the sweating rate and the salt loss rate via sweating would enable the early detection of heat-related illness in workers. We measured K+ concentration in sweat and calculated the Na+\/K+ ratio to evaluate its utility for estimating sweating rate and salt loss rate. We hypothesized that compared with single electrolyte concentrations, the Na+\/K+ ratio would be less affected by the rapid evaporation of sweat.<\/jats:p>\n                  <jats:p>Methods: Thirteen healthy males exercised on a bicycle ergometer in an artificial climate room, and their sweating rates and Na+ and K+ concentrations in sweat were measured. We also compared sealed and open methods of sweat collection, which respectively prevent or permit evaporation of sweat from the collection area.<\/jats:p>\n                  <jats:p>Results: When sweating rate increased, Na+ concentration increased, and K+ concentration decreased. Na+ concentration and the Na+\/K+ ratio were significantly lower among habitual exercisers. Sweating rate was more strongly associated with the Na+\/K+ ratio than with Na+ concentration. Similarly, the calculated NaCl loss rate was more strongly correlated with the Na+\/K+ ratio than with Na+ concentration. The open sweat collection method reliably demonstrated individual variation in the Na+\/K+ ratio.<\/jats:p>\n                  <jats:p>Conclusions: The Na+\/K+ ratio is more accurate than Na+ concentration for predicting sweating rate and the calculated NaCl loss rate because it accounts for individual sweat variation. The Na+\/K+ ratio is not influenced by sweat evaporation, and samples can be practically obtained by briefly applying absorbent paper to the skin surface.<\/jats:p>","DOI":"10.1093\/joccuh\/uiaf066","type":"journal-article","created":{"date-parts":[[2025,11,20]],"date-time":"2025-11-20T11:51:52Z","timestamp":1763639512000},"source":"Crossref","is-referenced-by-count":0,"title":["Sweat Na+\/K+ ratio as a practical biological index for estimating sweating rate and salt loss rate"],"prefix":"10.1093","volume":"67","author":[{"given":"Naoki","family":"Gommori","sequence":"first","affiliation":[{"name":"Keihin Occupational Health Center, JFE Steel Corporation East Japan Works Keihin , Kawasaki, Kanagawa Prefecture ,","place":["Japan"]},{"name":"Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health , Kitakyushu, Fukuoka Prefecture, \u00a0","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1430-6524","authenticated-orcid":false,"given":"Chikage","family":"Nagano","sequence":"additional","affiliation":[{"name":"Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health , Kitakyushu, Fukuoka Prefecture, \u00a0","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Takahiro","family":"Tanaka","sequence":"additional","affiliation":[{"name":"Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health , Kitakyushu, Fukuoka Prefecture, \u00a0","place":["Japan"]},{"name":"Occupational Health Center, Railway Systems Business Unit, Hitachi Ltd Kasado Works , Kudamatsu, Yamaguchi Prefecture ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuichiro","family":"Tanaka","sequence":"additional","affiliation":[{"name":"Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health , Kitakyushu, Fukuoka Prefecture, \u00a0","place":["Japan"]},{"name":"Division of Occupational Health, Sakai Plant, Daikin Industries Ltd , Sakai, Osaka Prefecture ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-0391-3312","authenticated-orcid":false,"given":"Kimiyo","family":"Mori","sequence":"additional","affiliation":[{"name":"Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health , Kitakyushu, Fukuoka Prefecture, \u00a0","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinro","family":"Inoue","sequence":"additional","affiliation":[{"name":"Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental Health , Kitakyushu, Fukuoka Prefecture, \u00a0","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shoko","family":"Kawanami","sequence":"additional","affiliation":[{"name":"Occupational Health Training Center, University of Occupational and Environmental Health , Kitakyushu, Fukuoka Prefecture ,","place":["Japan"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8347-2630","authenticated-orcid":false,"given":"Seichi","family":"Horie","sequence":"additional","affiliation":[{"name":"Department of Health Policy and Management, Institute of Industrial Ecological Sciences, University of Occupational and Environmental 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