{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,5]],"date-time":"2026-08-05T08:52:53Z","timestamp":1785919973598,"version":"3.56.0"},"reference-count":49,"publisher":"Oxford University Press (OUP)","issue":"8","funder":[{"name":"Cooperative Ecosystems Services Unit"},{"name":"U.S. Geological Survey to the Illinois Natural History Survey and by the U.S. Geological Survey\u2019s Environmental Health Program of the Ecosystem Mission Area"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,8,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Field assessments and laboratory studies have demonstrated that mayflies (Ephemeroptera) are relatively sensitive to increased concentrations of major geochemical ions (Na+, Ca2+, Mg2+, K+, Cl\u2212, SO42\u2212, HCO3\u2212\/CO32-), but much remains to be learned about potential mechanisms of toxicity. In the present study, we sought to determine whether solution osmolarity is sufficient to predict the toxic effects of major ions to a mayfly, Neocloeon triangulifer. We further investigated whether binary mixtures of major ion salts with common cations or common anions provide evidence of concentration addition or independent action, potentially illuminating toxicity drivers for this species. Finally, we sought to determine if there are mechanisms for major ion toxicity to mayflies that are comparable to those for other species. The toxicity of single salts showed a Ca-dependent correlation with the total component concentration (the sum of individual ion concentrations, a close correlate of osmolarity), but the effect concentrations were well below those causing toxicity from mannitol (presumed to have only an osmotic effect), suggesting that a general osmotic effect is not responsible for major ion toxicity in this species. The mixture experiments consistently indicated additive toxicity and consistency with the relationship to total component concentration, which supports a single toxic mechanism and thus no evidence for ion-specific mechanisms, as reported for other species. Given the lack of evidence of ion-specific toxicity, the total component metric is likely useful for a broad range of ionic compositions.<\/jats:p>","DOI":"10.1093\/etojnl\/vgag127","type":"journal-article","created":{"date-parts":[[2026,5,9]],"date-time":"2026-05-09T16:23:25Z","timestamp":1778343805000},"page":"2367-2377","source":"Crossref","is-referenced-by-count":0,"title":["Using organic compounds and salt mixtures to investigate potential mechanisms of major ion toxicity to the mayfly\n                    <i>Neocloeon triangulifer<\/i>"],"prefix":"10.1093","volume":"45","author":[{"given":"David J","family":"Soucek","sequence":"first","affiliation":[{"name":"Columbia Environmental Research Center, U.S. Geological Survey , Columbia, MO,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Russell J","family":"Erickson","sequence":"additional","affiliation":[{"name":"Great Lakes Toxicology and Ecology Division, U.S. Environmental Protection Agency , Duluth, MN,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Amy","family":"Dickinson","sequence":"additional","affiliation":[{"name":"Prairie Research Institute, Illinois Natural History Survey , Champaign, IL,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David R","family":"Mount","sequence":"additional","affiliation":[{"name":"Great Lakes Toxicology and Ecology Division, U.S. Environmental Protection Agency , Duluth, MN,","place":["United States"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,5,9]]},"reference":[{"key":"2026080504413978800_vgag127-B1","doi-asserted-by":"publisher","first-page":"E729","DOI":"10.1520\/E0729-96R14","volume-title":"Annual book of ASTM standards","author":"ASTM 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