{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T08:03:44Z","timestamp":1790841824525,"version":"4.1.0"},"reference-count":48,"publisher":"Oxford University Press (OUP)","issue":"10","license":[{"start":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T00:00:00Z","timestamp":1782518400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100008638","name":"Environment and Climate Change Canada","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100008638","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,10,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>A clear gap in ecotoxicological data was identified regarding the impacts of the technologically critical lanthanide neodymium (Nd) on soil invertebrates in boreal soil. To address this gap, two inorganic metal salts (NdCl3 and Nd2(SO4)3), an organometallic compound Nd-2-ethylhexanoate (Nd-2-EHA) and its organic component 2-ethylhexanoic acid (2-EHA) were examined. Toxicity exposures were conducted using the earthworm Dendrodrilus rubidus, the collembolan Proisotoma minuta, and the oribatid mite Oppia nitens, in two Canadian boreal soil horizons (i.e., organic and mineral), using standardized soil toxicity test methods; effects included survival and reproduction. Different exposure scenarios were investigated, including aging of test soil for 6\u00a0months, and the impact of leaching on toxicity test endpoints. Differences in species sensitivity were observed, with D. rubidus identified as the most sensitive test species. The study highlighted the importance of reporting chemical parameters within toxicity tests, such as electrical conductivity and pH, to better understand test system influences and factors affecting toxicity. Toxicity estimates from leached and aged NdCl3 exposures provided the least confounded assessment of Nd toxicity (reproductive median inhibitory concentration [IC50]\u00a0for D. rubidus: 890 [767\u2013950] mg Nd kg\u22121\u2009dry soil), as leaching reduced salt-related effects. Incorporating measures of extractable Nd proved valuable for comparing toxicity across the substances. Despite the lowest measured extractable and total Nd, the organometallic, Nd-2-EHA, was the most toxic compound tested (reproductive IC50 for D. rubidus: 17 [10\u201330] mg Nd kg\u22121\u2009dry soil), largely influenced by the organic component (2-EHA) when tested at equivalent concentrations. Exposure to 2-EHA and Nd-2-EHA demonstrated a significant decrease in toxicity with aging. These findings aligned with existing frameworks such that a metal-moiety approach may be insufficient for organometallics, wherein inorganic and organic influences must be considered.<\/jats:p>","DOI":"10.1093\/etojnl\/vgag156","type":"journal-article","created":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T15:35:34Z","timestamp":1782574534000},"page":"2897-2911","source":"Crossref","is-referenced-by-count":1,"title":["The toxicity of neodymium substances to soil invertebrates in a boreal soil, and the impacts of soil type, aging, and leaching on metal bioavailability and toxicity"],"prefix":"10.1093","volume":"45","author":[{"given":"Patrick","family":"Boyd","sequence":"first","affiliation":[{"name":"Ecotoxicology and Wildlife Health, Wildlife and Landscape Directorate, Environment and Climate Change Canada , Ottawa, ON,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dina","family":"Schwertfeger","sequence":"additional","affiliation":[{"name":"Ecotoxicology and Wildlife Health, Wildlife and Landscape Directorate, Environment and Climate Change Canada , Ottawa, ON,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heather","family":"Lemieux","sequence":"additional","affiliation":[{"name":"Ecotoxicology and Wildlife Health, Wildlife and Landscape Directorate, Environment and Climate Change Canada , Ottawa, ON,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jessica","family":"Velicogna","sequence":"additional","affiliation":[{"name":"Ecotoxicology and Wildlife Health, Wildlife and Landscape Directorate, Environment and Climate Change Canada , Ottawa, ON,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rick","family":"Scroggins","sequence":"additional","affiliation":[{"name":"Ecotoxicology and Wildlife Health, Wildlife and Landscape Directorate, Environment and Climate Change Canada , Ottawa, ON,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Juliska","family":"Princz","sequence":"additional","affiliation":[{"name":"Ecotoxicology and Wildlife Health, Wildlife and Landscape Directorate, Environment and Climate Change Canada , Ottawa, ON,","place":["Canada"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2026,6,27]]},"reference":[{"key":"2026100103520461400_vgag156-B1","author":"Avalon Rare Metals Inc (Avalon)","year":"2013"},{"key":"2026100103520461400_vgag156-B2","author":"Bureau Veritas","year":"2015"},{"key":"2026100103520461400_vgag156-B3","doi-asserted-by":"publisher","first-page":"e0129936","DOI":"10.1371\/journal.pone.0129936","article-title":"Uptake and effects of six rare earth elements (REEs) on selected native and crop species growing in contaminated soils","volume":"10","author":"Carpenter","year":"2015","journal-title":"PLoS One"},{"key":"2026100103520461400_vgag156-B4","doi-asserted-by":"publisher","first-page":"11481","DOI":"10.1021\/acs.est.6b02284","article-title":"Structure, variation, and co-occurrence of soil microbial communities in abandoned sites of a rare earth elements mine","volume":"50","author":"Chao","year":"2016","journal-title":"Environmental Science & Technology"},{"key":"2026100103520461400_vgag156-B5","author":"Comprehensive Environmental Toxicity Information System (CETIS)","year":"2000"},{"key":"2026100103520461400_vgag156-B6","doi-asserted-by":"publisher","first-page":"2406","DOI":"10.1016\/j.soilbio.2009.08.012","article-title":"Effect of some rare earth elements on the growth and lanthanide accumulation in different Trichoderma strains","volume":"41","author":"d\u2019Aquino","year":"2009","journal-title":"Soil Biology and Biochemistry"},{"key":"2026100103520461400_vgag156-B7","doi-asserted-by":"publisher","first-page":"689","DOI":"10.1007\/s10646-022-02542-6","article-title":"Effects of rare earth elements (REE) on terrestrial organisms: Current status and future directions","volume":"31","author":"Egler","year":"2022","journal-title":"Ecotoxicology"},{"key":"2026100103520461400_vgag156-B8","author":"Environment Canada (EC)","year":"2005"},{"key":"2026100103520461400_vgag156-B9","author":"Environment Canada (EC)","year":"2014"},{"key":"2026100103520461400_vgag156-B10","author":"Environment Canada (EC)","year":"2015"},{"key":"2026100103520461400_vgag156-B11","author":"Environment Canada (EC)","year":"2016"},{"key":"2026100103520461400_vgag156-B12","author":"Environment and Climate Change Canada (ECCC)","year":"2019"},{"key":"2026100103520461400_vgag156-B13","author":"Environment and Climate Change Canada (ECCC)","year":"2020"},{"key":"2026100103520461400_vgag156-B14","author":"Environment and Climate Change Canada (ECCC)","year":"2022"},{"key":"2026100103520461400_vgag156-B15","author":"Environment Canada and Health Canada (EC and HC)","year":"2011"},{"key":"2026100103520461400_vgag156-B16","doi-asserted-by":"publisher","first-page":"148","DOI":"10.1016\/j.envint.2014.06.019","article-title":"Environmental fate and ecotoxicity of lanthanides: Are they are uniform group beyond chemistry?","volume":"71","author":"Gonzalez","year":"2014","journal-title":"Environment International"},{"key":"2026100103520461400_vgag156-B17","doi-asserted-by":"publisher","first-page":"299","DOI":"10.1016\/j.scitotenv.2018.04.235","article-title":"Sources, behaviour, and environmental and human health risks of high-technology rare earth elements as emerging contaminants","volume":"636","author":"Gwenzi","year":"2018","journal-title":"Science of the Total Environment"},{"key":"2026100103520461400_vgag156-B100","volume-title":"Communications in Soil Science and Plant Analysis","year":"2000"},{"key":"2026100103520461400_vgag156-B18","doi-asserted-by":"publisher","first-page":"107361","DOI":"10.1016\/j.mimet.2025.107361","article-title":"New organic matter decomposition test method as an indicator for soil health","volume":"241","author":"Kvas","year":"2026","journal-title":"Journal of Microbiological Methods"},{"key":"2026100103520461400_vgag156-B19","doi-asserted-by":"publisher","first-page":"957","DOI":"10.1016\/S1002-0721(09)60233-7","article-title":"Effects of the accumulation of the rare earth elements on soil macrofauna community","volume":"28","author":"Li","year":"2010","journal-title":"Journal of Rare Earths"},{"key":"2026100103520461400_vgag156-B20","doi-asserted-by":"publisher","first-page":"412","DOI":"10.1016\/j.chemosphere.2017.11.040","article-title":"Lanthanum toxicity to five different species of soil invertebrates in relation to availability in soil","volume":"193","author":"Li","year":"2018","journal-title":"Chemosphere"},{"key":"2026100103520461400_vgag156-B21","doi-asserted-by":"publisher","first-page":"132487","DOI":"10.1016\/j.jhazmat.2023.132487","article-title":"A toxicokinetics approach using Enchytraeus crypticus to evaluate the efficiency of hydroxyapatite to remediate soils contaminated with rare earth elements","volume":"460","author":"Li","year":"2023","journal-title":"Journal of Hazardous Materials"},{"key":"2026100103520461400_vgag156-B22","doi-asserted-by":"publisher","first-page":"1336","DOI":"10.1039\/C7EM00082K","article-title":"Rare earth elements in freshwater, marine, and terrestrial ecosystems in the eastern Canadian Arctic","volume":"19","author":"MacMillan","year":"2017","journal-title":"Environmental Science. Processes & Impacts"},{"key":"2026100103520461400_vgag156-B23","doi-asserted-by":"publisher","first-page":"1663","DOI":"10.3390\/ani10091663","article-title":"An update review of toxicity effect of the rare earth elements (REEs) on aquatic organisms","volume":"10","author":"Malhotra","year":"2020","journal-title":"Animals"},{"key":"2026100103520461400_vgag156-B24","doi-asserted-by":"publisher","first-page":"826","DOI":"10.1071\/SRI5073","article-title":"Can the application of rare earth elements improve yield and decrease the uptake of cadmium in ryegrass-dominated pastures?","volume":"53","author":"McDowell","year":"2015","journal-title":"Soil Research"},{"key":"2026100103520461400_vgag156-B25","doi-asserted-by":"publisher","first-page":"8135","DOI":"10.1021\/es500141h","article-title":"Differences in soil solution chemistry between soils amended with nanosized CuO or Cu reference materials: Implications for nanotoxicity tests","volume":"48","author":"McShane","year":"2014","journal-title":"Environmental Science & Technology"},{"key":"2026100103520461400_vgag156-B26","doi-asserted-by":"publisher","first-page":"141438","DOI":"10.1016\/j.scitotenv.2020.141438f","article-title":"Agrochemical treatments as a source of heavy metals and rare earth elements in agricultural soils and bioaccumulation in ground beetles","volume":"749","author":"Naccarato","year":"2020","journal-title":"Science of the Total Environment"},{"key":"2026100103520461400_vgag156-B27","author":"Natural Resources Canada (NRCan)","year":"2024"},{"key":"2026100103520461400_vgag156-B28","author":"Organisation for Economic Co-operation and Development","year":"2015"},{"key":"2026100103520461400_vgag156-B29","doi-asserted-by":"publisher","first-page":"2385","DOI":"10.1016\/j.soilbio.2008.05.019","article-title":"Effects of salinity on partitioning, uptake and toxicity of zinc in the earthworm Eisenia fetida","volume":"40","author":"Owojori","year":"2008","journal-title":"Soil Biology and Biochemistry"},{"key":"2026100103520461400_vgag156-B30","doi-asserted-by":"publisher","first-page":"351","DOI":"10.1016\/j.pedobi.2008.12.002","article-title":"Comparative study of the effects of salinity on life-cycle parameters of four soil-dwelling species (Folsomia candida, Enchytraeus doerjesi, Eisenia fetida and Aporrectodea caliginosa)","volume":"52","author":"Owojori","year":"2009","journal-title":"Pedobiologia"},{"key":"2026100103520461400_vgag156-B31","doi-asserted-by":"publisher","first-page":"135723","DOI":"10.1016\/j.chemosphere.2022.135723","article-title":"Phytotoxicity effect concentrations (ECx) for Ce, Nd and Eu added to soil relative to total and bioaccessible soil REE concentrations, and tissue REE accumulations","volume":"307","author":"Pellegrino","year":"2022","journal-title":"Chemosphere"},{"key":"2026100103520461400_vgag156-B32","doi-asserted-by":"publisher","first-page":"116","DOI":"10.1016\/j.chemosphere.2015.03.094","article-title":"Effects of NaCl and seawater induced salinity on survival and reproduction of three soil invertebrate species","volume":"135","author":"Pereira","year":"2015","journal-title":"Chemosphere"},{"key":"2026100103520461400_vgag156-B33","doi-asserted-by":"publisher","first-page":"766","DOI":"10.1002\/etc.1744","article-title":"Evaluation of a new battery of toxicity tests for boreal forest soils: Assessment of the impact of hydrocarbons and salts","volume":"31","author":"Princz","year":"2012","journal-title":"Environmental Toxicology and Chemistry"},{"key":"2026100103520461400_vgag156-B35","doi-asserted-by":"publisher","first-page":"28","DOI":"10.1007\/s40726-016-0026-4","article-title":"Rare earth elements in the soil environment","volume":"2","author":"Ramos","year":"2016","journal-title":"Current Pollution Reports"},{"key":"2026100103520461400_vgag156-B34","doi-asserted-by":"publisher","first-page":"177","DOI":"10.1016\/j.gexplo.2016.06.009","article-title":"Rare earth elements in raw materials and products of the phosphate fertilizer industry in South America: Content, signature, and crystalline phases","volume":"168","author":"Ramos","year":"2016","journal-title":"Journal of Geochemical Exploration"},{"key":"2026100103520461400_vgag156-B36","doi-asserted-by":"publisher","first-page":"2263","DOI":"10.1002\/cjce.23152","article-title":"Accumulation and toxicity of lanthanum and neodymium in horticultural plants (Brassica chinensis L. and Helianthus annuus L.)","volume":"96","author":"Rezaee","year":"2018","journal-title":"The Canadian Journal of Chemical Engineering"},{"key":"2026100103520461400_vgag156-B37","doi-asserted-by":"publisher","first-page":"3324","DOI":"10.1002\/etc.3910","article-title":"The ecotoxicity of zinc and zinc-containing substances in soil-consideration for metal moiety approaches and organo-metal complexes","volume":"36","author":"Ritchie","year":"2017","journal-title":"Environmental Toxicology and Chemistry"},{"key":"2026100103520461400_vgag156-B38","doi-asserted-by":"publisher","first-page":"143","DOI":"10.1016\/j.jre.2020.12.006","article-title":"Fractionation and fixation of rare earth elements in soils: Effect of spiking with lanthanum, cerium, and neodymium chlorides","volume":"40","author":"Rogova","year":"2022","journal-title":"Journal of Rare Earths"},{"key":"2026100103520461400_vgag156-B39","doi-asserted-by":"publisher","first-page":"72336","DOI":"10.1007\/s11356-023-27313-6","article-title":"Cerium oxide nanoparticles (nCeO2) exert minimal adverse effects on microbial communities in soils with and without biosolids amendment","volume":"30","author":"Samarajeewa","year":"2023","journal-title":"Environmental Science and Pollution Research"},{"key":"2026100103520461400_vgag156-B40","doi-asserted-by":"publisher","first-page":"2253","DOI":"10.1002\/etc.1904","article-title":"Comparing soil chemistries of leached and nonleached copper-amended soils","volume":"31","author":"Schwertfeger","year":"2012","journal-title":"Environmental Toxicology and Chemistry"},{"key":"2026100103520461400_vgag156-B41","doi-asserted-by":"publisher","first-page":"1570","DOI":"10.1080\/00103624.2012.760576","article-title":"Spike\/leach procedure to prepare soil samples for trace metal ecotoxicity testing: Method development using copper","volume":"44","author":"Schwertfeger","year":"2013","journal-title":"Communications in Soil Science and Plant Analysis"},{"key":"2026100103520461400_vgag156-B42","doi-asserted-by":"publisher","first-page":"3761","DOI":"10.1021\/es304524p","article-title":"A general model for kinetics of heavy metal adsorption and desorption on soils","volume":"47","author":"Shi","year":"2013","journal-title":"Environmental Science & Technology"},{"key":"2026100103520461400_vgag156-B43","doi-asserted-by":"publisher","first-page":"1633","DOI":"10.1897\/08-592.1","article-title":"Toxicity of trace metals in soil as affected by soil type and aging after contamination: Using calibrated bioavailability models to set ecological soil standards","volume":"28","author":"Smolders","year":"2009","journal-title":"Environmental Toxicology and Chemistry"},{"key":"2026100103520461400_vgag156-B44","doi-asserted-by":"publisher","first-page":"3017","DOI":"10.1897\/02-290","article-title":"Determining toxicity of lead and zinc runoff in soils: Salinity effects on metal partitioning and on phytotoxicity","volume":"22","author":"Stevens","year":"2003","journal-title":"Environmental Toxicology and Chemistry"},{"key":"2026100103520461400_vgag156-B45","author":"SYSTAT","year":"2009"},{"key":"2026100103520461400_vgag156-B46","doi-asserted-by":"publisher","first-page":"39","DOI":"10.3184\/095422901783726825","article-title":"The influence of rare earth element fertilizer application on the distribution and bioaccumulation of rare earth elements in plants under field conditions","volume":"13","author":"Wen","year":"2001","journal-title":"Chemical Speciation & Bioavailability"},{"key":"2026100103520461400_vgag156-B47","doi-asserted-by":"publisher","first-page":"395","DOI":"10.1016\/S0269-7491(00)00143-3","article-title":"Speciation of rare earth elements in soil and accumulation by wheat with rare earth fertilizer application","volume":"112","author":"Zhang","year":"2001","journal-title":"Environmental Pollution"}],"container-title":["Environmental Toxicology and Chemistry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/academic.oup.com\/etc\/advance-article-pdf\/doi\/10.1093\/etojnl\/vgag156\/68632796\/vgag156.pdf","content-type":"application\/pdf","content-version":"am","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/etc\/article-pdf\/45\/10\/2897\/68632796\/vgag156.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/etc\/article-pdf\/45\/10\/2897\/68632796\/vgag156.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T07:52:08Z","timestamp":1790841128000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/etc\/article\/45\/10\/2897\/8719539"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,27]]},"references-count":48,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2026,6,27]]},"published-print":{"date-parts":[[2026,10,1]]}},"URL":"https:\/\/doi.org\/10.1093\/etojnl\/vgag156","relation":{},"ISSN":["0730-7268","1552-8618"],"issn-type":[{"value":"0730-7268","type":"print"},{"value":"1552-8618","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2026,10]]},"published":{"date-parts":[[2026,6,27]]}}}