{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,8]],"date-time":"2026-08-08T01:45:15Z","timestamp":1786153515895,"version":"build-2736575974"},"reference-count":85,"publisher":"Wiley","license":[{"start":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T00:00:00Z","timestamp":1786060800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,8,7]],"date-time":"2026-08-07T00:00:00Z","timestamp":1786060800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100022252","name":"Department of Forestry, Fisheries and the Environment","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100022252","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001321","name":"National Research Foundation","doi-asserted-by":"publisher","award":["75911"],"award-info":[{"award-number":["75911"]}],"id":[{"id":"10.13039\/501100001321","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Environmental Toxicology"],"abstract":"<jats:title>ABSTRACT<\/jats:title>\n                  <jats:p>\n                    Metal contamination in estuarine environments poses environmental and public health concerns, particularly where surface waters support domestic and subsistence uses. This study assessed the seasonal distribution, controlling mechanisms, and non\u2010carcinogenic health risks of selected metals (Mg, Al, Ba, Fe, Mn, and Zn) in the Buffalo River Estuary, Eastern Cape, South Africa. Water samples were collected from 11 stations during wet and dry seasons and analyzed using standard methods. Descriptive statistics, Pearson's correlation analysis, and principal component analysis (PCA) were applied to evaluate metal distribution, inter\u2010element relationships, and dominant controlling processes. Marked seasonal variability was observed, with higher concentrations of Al (97\u20131708\u2009\u03bcg\/L), Ba (7.4\u201329\u2009\u03bcg\/L), Fe (54\u20131751\u2009\u03bcg\/L), Mn (4\u2013116\u2009\u03bcg\/L), and Zn (4\u201323\u2009\u03bcg\/L) during the wet season, while Mg concentrations were elevated in the dry season (10686\u2013851\u2009382\u2009\u03bcg\/L) relative to the wet season (1056\u20131313\u2009\u03bcg\/L). PCA indicated that wet\u2010season metal dynamics were governed by lithogenic and hydrological processes linked to runoff and suspended sediments, whereas dry\u2010season variability reflected sedimentary geochemical controls, redox processes, conservative mixing, and secondary anthropogenic inputs. Non\u2010carcinogenic health risk assessment for Al, Ba, Fe, Mn, and Zn showed Mn as the largest contributor to risk, although cumulative hazard indices for adults (2.19\u2009\u00d7\u200910\n                    <jats:sup>\u22122<\/jats:sup>\n                    \u20131.39\u2009\u00d7\u200910\n                    <jats:sup>\u22121<\/jats:sup>\n                    ) and children (8.10\u2009\u00d7\u200910\n                    <jats:sup>\u22122<\/jats:sup>\n                    \u20135.01\u2009\u00d7\u200910\n                    <jats:sup>\u22121<\/jats:sup>\n                    ) remained below unity, indicating low health risk. These findings highlight the dominance of seasonal geochemical processes, providing essential baseline data for water\u2010quality management, and underscore the need for continued monitoring to support effective water\u2010resource management.\n                  <\/jats:p>","DOI":"10.1002\/tox.70177","type":"journal-article","created":{"date-parts":[[2026,8,8]],"date-time":"2026-08-08T01:40:22Z","timestamp":1786153222000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Assessment of Metal Contamination and Human Health Risk in the Buffalo River Estuary, Eastern Cape, South Africa"],"prefix":"10.1002","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6382-3165","authenticated-orcid":false,"given":"Motebang D. V.","family":"Nakin","sequence":"first","affiliation":[{"name":"Centre for Global Change Walter Sisulu University  Mthatha South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5316-4015","authenticated-orcid":false,"given":"Tolulope Elizabeth","family":"Aniyikaiye","sequence":"additional","affiliation":[{"name":"Civil Engineering Department Walter Sisulu University  East London Eastern Cape South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7992-8789","authenticated-orcid":false,"given":"Akinola","family":"Ikudayisi","sequence":"additional","affiliation":[{"name":"Civil Engineering Department Walter Sisulu University  East London Eastern Cape South Africa"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2026,8,7]]},"reference":[{"key":"e_1_2_12_2_1","first-page":"1","article-title":"Surface Water Quality Profiling Using the Water Quality Index, Pollution Index and Statistical Methods: A Critical Review","volume":"18","author":"Syeed M. 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