{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:11:05Z","timestamp":1760231465074,"version":"build-2065373602"},"reference-count":55,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,9,20]],"date-time":"2022-09-20T00:00:00Z","timestamp":1663632000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"United States Department of Agriculture","award":["2003-05495","17-DG-11052021-217"],"award-info":[{"award-number":["2003-05495","17-DG-11052021-217"]}]},{"DOI":"10.13039\/100006959","name":"Unites States Forest Service","doi-asserted-by":"publisher","award":["2003-05495","17-DG-11052021-217"],"award-info":[{"award-number":["2003-05495","17-DG-11052021-217"]}],"id":[{"id":"10.13039\/100006959","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxics"],"abstract":"<jats:p>Exposure to environmental toxins may be partly responsible for mammal neurodegenerative disorders. Consumption of seeds from Guam\u2019s cycad tree has been linked to the disorder known as amyotrophic lateral sclerosis-parkinsonism dementia complex (ALS-PDC). The unambiguous identification of causal agents of ALS-PDC has been elusive. We have examined the levels of eight metals and metalloids in cycad seeds as a function of the ambient shade in which the plants were grown. Of these metals, the data strongly suggest that aluminum (Al) and selenium (Se) are present in washed flour prepared from southern Guam\u2019s cycad seed tissues at elevated levels, especially when the trees are grown in shade. Previous authors have speculated that Al and Se are involved in various ALS outcomes, and our results support this interpretation.<\/jats:p>","DOI":"10.3390\/toxics10100550","type":"journal-article","created":{"date-parts":[[2022,9,21]],"date-time":"2022-09-21T00:08:09Z","timestamp":1663718889000},"page":"550","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Metals and Metalloids Increase in Cycas micronesica Seed Gametophyte Tissue in Shaded Growth Conditions"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7348-2632","authenticated-orcid":false,"given":"Thomas E.","family":"Marler","sequence":"first","affiliation":[{"name":"Bagong Kaalaman Botanikal Institute, 15 Rizal Street, Barangay Malaba\u00f1as, Angeles City 2009, Philippines"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christopher A.","family":"Shaw","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver, BC V5Z 1M9, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,20]]},"reference":[{"key":"ref_1","unstructured":"Zimmerman, H. 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