High aluminum content in bone of marine mammals and its relation with source levels and origin

• Published in: Environmental pollution (1987) Vol. 331; no. Pt 1; p. 121936
• Main Authors: Borrell, A., Garcia-Garin, O., Aguilar, A., Vighi, M., Valdivia, M., González, E.M., Páez-Rosas, D., Drago, M.
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 15-08-2023
• Subjects: Aluminum; Animals; Atlantic ocean; Cetacean; Ecosystem; Environmental Monitoring; Estuaries; Mammals; Pinniped; Skull; Trace element; Uruguay; Uruguay; Trace element; Skull; Cetacean; Atlantic ocean; Pinniped
• ISSN: 0269-7491; 1873-6424
• DOI: 10.1016/j.envpol.2023.121936

Although aluminum is widely distributed in the earth's crust, its environmental availability and wildlife assimilation rates are only partially known. Here we analyze aluminum concentrations in bone from 10 species of marine mammals inhabiting 3 geographic areas subject to different aluminum inputs: the Río de la Plata estuary (Uruguay), the coastal waters of Mauritania and the Galapagos archipelago (Ecuador). Overall, concentrations were unusually high as compared to those of terrestrial animals, with lowest concentrations in the Galapagos archipelago, then the Río de la Plata estuary and finally Mauritania. The aluminum source varied between regions, prevailing anthropogenic sources in the Río de la Plata Estuary and natural sources (wind-blown dust) in Mauritanian waters. The type of source determined contamination levels: anthropogenic sources were most significant for coastal species and showed a decline with distance of habitat from shoreline, while natural sources had a higher influence on open waters because of the dearth of biogenic silica that eliminates aluminum from the water column. Since aluminum remains in bone for several decades, marine mammal bone reflects historical levels of aluminum and therefore is a good bioindicator of the aluminum concentration of the marine environment.
[Display omitted]
•We analyzed Al in bone of 4 pinnipeds and 6 cetaceans from 3 areas.•Al levels followed an increase gradient: Galapagos, Río de la Plata, Mauritania.•Main Al source for Río de la Plata was anthropic, for Mauritania wind-blown dust.•Anthropic sources had short-range impact, natural sources long-range impact.•Marine mammals are good bioindicators of Al contamination levels and type.