{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T18:36:39Z","timestamp":1783017399231,"version":"3.54.6"},"reference-count":8,"publisher":"Wiley","issue":"7","license":[{"start":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T00:00:00Z","timestamp":1779321600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by-nc-nd\/4.0\/"},{"start":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T00:00:00Z","timestamp":1779321600000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/100017060","name":"California Horse Racing Board","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100017060","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["analyticalsciencejournals.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Drug Testing and Analysis"],"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>Metformin is a diabetes medication with minimal therapeutic efficacy in veterinary medicine. However, recently there have been several adverse analytical findings in regulatory samples collected from racehorses. Metformin is commonly prescribed to humans, is excreted unchanged in urine, and is resistant to environmental degradation, raising concerns with respect to environmental contamination. In this study, six horses were exposed to shavings contaminated with metformin\u2010positive urine at concentrations of 10, 135, and 270\u2009\u03bcg\/mL. Blood (plasma, serum, whole blood, and red blood cells) and urine samples were collected for 168\u2009h post\u2010exposure for determination of metformin concentrations. All horses had detectable metformin concentrations in blood samples at least once during the sample collection period. Metformin concentrations in urine samples greatly exceeded those in blood and were detectable as early as 4\u2009h post\u2010contamination. The presence of metformin in these samples raises the possibility of metformin exposure through contamination, especially given the housing conditions at racetracks. The potential for exposure through contamination, resulting in adverse analytical findings, should be considered in the regulation of metformin in racehorses.<\/jats:p>","DOI":"10.1002\/dta.70096","type":"journal-article","created":{"date-parts":[[2026,5,21]],"date-time":"2026-05-21T13:56:31Z","timestamp":1779371791000},"page":"945-950","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Investigation of Metformin Contamination in Horses: Implications for Environmental Exposure and Doping Control"],"prefix":"10.1002","volume":"18","author":[{"given":"Megan\u00a0E.","family":"Jacobs","sequence":"first","affiliation":[{"name":"K.L. Maddy Equine Analytical Chemistry Laboratory (Pharmacology Section) School of Veterinary Medicine, University of California  Davis California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeff","family":"Blea","sequence":"additional","affiliation":[{"name":"School of Veterinary Medicine University of California  Davis California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Hardy","sequence":"additional","affiliation":[{"name":"Racing Medication and Testing Consortium  Lexington Kentucky USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daniel\u00a0S.","family":"McKemie","sequence":"additional","affiliation":[{"name":"K.L. Maddy Equine Analytical Chemistry Laboratory (Pharmacology Section) School of Veterinary Medicine, University of California  Davis California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Megan","family":"Traynham","sequence":"additional","affiliation":[{"name":"K.L. Maddy Equine Analytical Chemistry Laboratory (Pharmacology Section) School of Veterinary Medicine, University of California  Davis California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8676-4970","authenticated-orcid":false,"given":"Heather\u00a0K.","family":"Knych","sequence":"additional","affiliation":[{"name":"K.L. Maddy Equine Analytical Chemistry Laboratory (Pharmacology Section) School of Veterinary Medicine, University of California  Davis California USA"},{"name":"Department of Molecular Biosciences, School of Veterinary Medicine University of California  Davis California USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,5,21]]},"reference":[{"key":"e_1_2_9_2_1","doi-asserted-by":"publisher","DOI":"10.1007\/s40261\u2010019\u201000799\u20100"},{"key":"e_1_2_9_3_1","doi-asserted-by":"publisher","DOI":"10.1007\/BF00562061"},{"key":"e_1_2_9_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.watres.2012.06.019"},{"key":"e_1_2_9_5_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.tvjl.2011.01.015"},{"key":"e_1_2_9_6_1","doi-asserted-by":"publisher","DOI":"10.1002\/dta.70000"},{"key":"e_1_2_9_7_1","unstructured":"Fda Cder \u201cBioanalytical Method Validation Guidance for Industry Biopharmaceutics Bioanalytical Method Validation Guidance for Industry Biopharmaceutics Contains Nonbinding Recommendations \u201d (2018) https:\/\/www.fda.gov\/files\/drugs\/published\/Bioanalytical\u2010Method\u2010Validation\u2010Guidance\u2010for\u2010Industry.pdf."},{"key":"e_1_2_9_8_1","doi-asserted-by":"publisher","DOI":"10.1016\/s1262\u20103636(07)70037\u2010x"},{"key":"e_1_2_9_9_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12917\u2010026\u201005449\u20100"}],"container-title":["Drug Testing and Analysis"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/analyticalsciencejournals.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/dta.70096","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/analyticalsciencejournals.onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/dta.70096","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/analyticalsciencejournals.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/dta.70096","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T17:36:18Z","timestamp":1783013778000},"score":1,"resource":{"primary":{"URL":"https:\/\/analyticalsciencejournals.onlinelibrary.wiley.com\/doi\/10.1002\/dta.70096"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,21]]},"references-count":8,"journal-issue":{"issue":"7","published-print":{"date-parts":[[2026,7]]}},"alternative-id":["10.1002\/dta.70096"],"URL":"https:\/\/doi.org\/10.1002\/dta.70096","archive":["Portico"],"relation":{},"ISSN":["1942-7603","1942-7611"],"issn-type":[{"value":"1942-7603","type":"print"},{"value":"1942-7611","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,21]]},"assertion":[{"value":"2025-09-03","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-05-13","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2026-05-21","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}