RT Journal Article
T1 The return of natural lead to the Northeast Atlantic Ocean captured by brown algae
A1 Pacín Salvador, María do Carme
A1 Aboal Viñas, Jesús
A1 Fernández Escribano, José Ángel
A1 Vázquez Arias, Antón
A1 Šípková, Adéla
A1 Komárek, Michael
A1 Chrastný, Vladislav
K1 Stable isotopes
K1 Heavy metal
K1 Potentially Toxic Elements
K1 Temporal trend
K1 Pollution
K1 Biomonitoring
K1 Seaweed
AB Lead (Pb) is a highly toxic pollutant with serious ecological implications. This study investigates 30-year trends (1990–2021) in Pb concentrations and isotopic signatures (206Pb/207Pb and 208Pb/206Pb) in the brown algae Fucus spp. from the Northeast Atlantic Ocean (n = 446). Pb concentrations showed only modest, non-significant 21.9 % decline. In contrast, isotopic data revealed a clear shift from anthropogenic to natural sources. Bayesian mixing models (MixSIAR) supported this trend, indicating an increase in natural contributions, rising from 4.7 % in 1990 to 61.5 % in 2021, mirroring reductions in coal combustion (from 48.4 % to 6.3 %) and petrol-related sources (from 46.9 % to 32.2 %). This divergence between concentrations and isotopic trends likely reflects a substantial increase in sediment-derived Pb (189.3 % in 2021 compared to 13–49 % during 1990–2007), as well as enhanced bioavailability driven by environmental changes such as ocean acidification. Elevated Pb levels were found in inner estuarine zones dominated by Fucus ceranoides, but no latitudinal pattern or isotopic differences among species were observed. Overall, the findings highlight the complex dynamics of Pb in coastal ecosystems and the limitations of relying solely on concentration data to assess pollution trends. Isotope analyses have proven essential for source attribution, revealing a progressive shift toward natural Pb sources and supporting the effectiveness of regulatory measures such as the global phase-out of leaded gasoline. However, the study underscores that increased Pb bioavailability, driven by acidification and other global environmental changes, may offset the benefits of reduced emissions. Finally, this work provides a valuable isotopic baseline for a region where such data remain scarce, supporting future environmental monitoring and source-tracing efforts.
PB Elsevier
SN 0304-3894
YR 2025
FD 2025-07-17
LK https://hdl.handle.net/10347/43893
UL https://hdl.handle.net/10347/43893
LA eng
NO Pacín, C., Aboal, J. R., Fernández, J. Á, Vázquez-Arias, A., Šípková, A., Komárek, M., & Chrastný, V. (2025). The return of natural lead to the Northeast Atlantic Ocean captured by brown algae. Journal of Hazardous Materials, 496, 139289. 10.1016/j.jhazmat.2025.139289
NO C. Pacín was supported by a predoctoral grant from Xunta de Galicia (ED481A 2022/374) and a research stay grant from CRETUS, which enabled isotope measurements during her stay in the Czech Republic. We sincerely thank Dr. Teresa Taboada for her assistance in selecting representative rock formations from the study area. We also thank Julia Bairstow for her careful revision of the English language. Finally, we thank the anonymous reviewers for their constructive comments, which significantly improved the quality of the manuscript.
DS Minerva
RD 29 abr 2026