<?xml version='1.0' encoding='utf-8'?>
<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:contributor>Danielle M. Cleveland</dc:contributor>
  <dc:contributor>David D. Harper</dc:contributor>
  <dc:contributor>Rebecca A. Dorman</dc:contributor>
  <dc:contributor>Aida Farag</dc:contributor>
  <dc:creator>John M. Besser</dc:creator>
  <dc:date>2026</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;Chronic selenium (Se) water quality criteria are based primarily on dietary organoselenium exposure and subsequent reproductive effects in fish. Available chronic Se toxicity data suggests that invertebrates are less sensitive than fish, but chronic invertebrate studies are limited. We evaluated yeast-based diets for chronic toxicity studies with&amp;nbsp;&lt;/span&gt;&lt;i&gt;Hyalella azteca&lt;/i&gt;&lt;span&gt;&amp;nbsp;and&amp;nbsp;&lt;/span&gt;&lt;i&gt;Chironomus dilutus.&lt;/i&gt;&lt;span&gt;&amp;nbsp;Growth and survival were similar among&amp;nbsp;&lt;/span&gt;&lt;i&gt;C. dilutus&lt;/i&gt;&lt;span&gt;&amp;nbsp;fed a yeast-only diet, a mixture of yeast and fish flake food, and a mixture of yeast and diatoms. Survival and growth of&amp;nbsp;&lt;/span&gt;&lt;i&gt;H. azteca&lt;/i&gt;&lt;span&gt;&amp;nbsp;were best in the yeast + diatom diet, so this diet was used for subsequent tests. In rangefinder tests,&amp;nbsp;&lt;/span&gt;&lt;i&gt;H. azteca&lt;/i&gt;&lt;span&gt;&amp;nbsp;28-day survival, growth, and biomass, and&amp;nbsp;&lt;/span&gt;&lt;i&gt;C. dilutus&lt;/i&gt;&lt;span&gt;&amp;nbsp;11-day survival were all significantly reduced at a dietary Se concentration of 49 µg/g dry weight, whereas&amp;nbsp;&lt;/span&gt;&lt;i&gt;C. dilutus&lt;/i&gt;&lt;span&gt;&amp;nbsp;growth and biomass were only affected at 200 µg/g dry weight Se.&amp;nbsp;&lt;/span&gt;&lt;i&gt;H. azteca&lt;/i&gt;&lt;span&gt;&amp;nbsp;had similar sensitivity to dietary Se in a 28–42-day chronic test—survival, growth, and biomass were significantly reduced at 44.5 µg/g dry weight Se. Dietary selenium reduced&amp;nbsp;&lt;/span&gt;&lt;i&gt;H. azteca&lt;/i&gt;&lt;span&gt;&amp;nbsp;reproduction by 75%–100% relative to Controls, but differences were not significant.&lt;/span&gt;&lt;/p&gt;&lt;p&gt;&lt;span&gt;Tissue Se EC10s were lower for&amp;nbsp;&lt;i&gt;H. azteca&lt;/i&gt;&amp;nbsp;(9.0–23 µg/g dry weight) than for&amp;nbsp;&lt;i&gt;C. dilutus&lt;/i&gt;&amp;nbsp;(11–56 µg/g dry weight). However, model evaluations suggest that the&amp;nbsp;&lt;i&gt;C. dilutus&lt;/i&gt;&amp;nbsp;11-day survival and&amp;nbsp;&lt;i&gt;H. azteca&lt;/i&gt;&amp;nbsp;42-day EC10s were less reliable than other endpoints. When tissue EC10s were converted to equivalent Se concentrations in fish tissue with a food web model,&amp;nbsp;&lt;i&gt;H. azteca&lt;/i&gt;&amp;nbsp;(18 µg/g dry weight) and C&lt;i&gt;. dilutus&lt;/i&gt;&amp;nbsp;(68 µg/g dry weight) ranked 6th and 12th of 13 freshwater genera, respectively. Overall, these results suggest that the current U.S. Environmental Protection Agency tissue-based Se water quality criteria would be protective for fish and invertebrates and could be used for management of fishless waters.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1093/etojnl/vgaf231</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Society and Environmental Toxicology and Chemistry</dc:publisher>
  <dc:title>Effects of dietary selenium on the amphipod Hyalella azteca and the midge Chironomus dilutus</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>