Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Baseline Recent trace metal enrichment and sediment quality assessment in an anthropized coastal lagoon (SE Gulf of California) from 210 Pb-dated sediment cores Jorge Feliciano Ontiveros-Cuadras a , Ana Carolina Ruiz-Fernández b,∗ , Libia Hascibe Pérez-Bernal b , Jorge Luis Serrato de la Peña c , Joan-Albert Sanchez-Cabeza b a Universidad Nacional Autónoma de México, Unidad Académica Procesos Oceánicos y Costeros, Instituto de Ciencias del Mar y Limnología, Ciudad Universitaria, 04510, Coyoacán, Mexico b Universidad Nacional Autónoma de México, Unidad Académica Mazatlán, Instituto de Ciencias del Mar y Limnología, Calz. Joel Montes Camarena s/n, 82040, Mazatlán, Mexico c Universidad Nacional Autónoma de México, Posgrado en Ciencias del Mar y Limnología, Unidad Académica Mazatlán, Calz. Joel Montes Camarena s/n, 82040, Mazatlán, Mexico ARTICLEINFO Keywords: 210 Pb-chronology Metal contamination Gulf of California large marine ecosystem Estero de Urías lagoon Sediment records ABSTRACT Concentrations and enrichment of major (Na, Al and Cl) and trace (V, Mn, Fe, Ni, Cu, Zn, As, Br, Mo, Hg, Pb and U) elements were evaluated in 210 Pb-dated sediment cores from saltmarsh areas surrounding an anthropized lagoon at southeastern Gulf of California. A chemometric approach was used to identify the sedimentary pro- cesses that control the variability of elements among the cores; and the elemental fuxes were compared among coring sites on the basis of historical urbanization and industrial development in the area. The highest fuxes and excess concentrations of V, Ni, Hg and Pb were observed after 1960 in cores EUI and EUIII, and in 1980 at EUII. In general, the historical trends of metal enrichment coincide with the growth of urban and industrial devel- opments around the lagoon, and particularly with the beginning and full operation of a thermoelectric power plant in 1980s. Coastal zones have been focal points of human settlement, whose growing rate and socioeconomic development has dramatically ac- celerated during the past 150 years (Lotze et al., 2006). Currently more than 40% of the world's population lives in large cities near the coast (i.e. ∼100 km; FAO, 2019) and such demographic force generates es- calating impacts, such as those reported in many coastal lagoons worldwide, owing to land-use changes in surrounding watersheds (Kennish and Paerl, 2010). Coastal lagoons are inland shallow water bodies, considered as highly productive ecosystems that functions as transitional zones be- tween land and sea (Kjerfve, 1994). These ecosystems are severely threatened by a large number of anthropogenic process such metal contamination, which afects both water and sediment quality (Pignotti et al., 2018). Sediments may act as sink and/or source of metal con- taminants (e.g. depending on redox conditions) and can represent an ecological risk due to the potential transfer of metals to biota and hu- mans through fsh consumption (Ontiveros-Cuadras et al., 2014). 210 Pb dating has been extensively applied in sediment records to reconstruct the trends of metal contamination over the last 100–150 years in coastal environments (Ruiz-Fernández and Hillaire-Marcel, 2009; Ruiz- Fernández et al., 2012). Estero de Urías lagoon (EUL) is an anthropized coastal ecosystem, in which previous studies have indicated a growing metal pollution pro- blem (e.g. Cu, Zn, Hg and Pb), particularly at the inner lagoon area, where the discharges from the thermoelectric plant and the industrial zone are located (Soto-Jiménez and Páez-Osuna, 2001; Jara-Marini et al., 2008; Ruiz-Fernández et al., 2009, 2018; Raygoza-Viera et al., 2014). The main goal of this study was to evaluate the distribution, enrichment and the historical fuxes of trace metals in three 210 Pb-dated sediment cores from the saltmarsh areas in the surroundings of EUL, under the hypothesis that metal pollution started at the beginning of the last century due to the regional socioeconomic development, and have accelerated at least during the last 40 years as a result of the urban and industrial activities that take place around the lagoon. In addition, a discussion of the potential provenance of the pollutants and an assess- ment of the ecological risk of sediments for the biota is provided. https://doi.org/10.1016/j.marpolbul.2019.110653 Received 23 May 2019; Received in revised form 30 September 2019; Accepted 7 October 2019 ∗ Corresponding author. E-mail address: caro@ola.icmyl.unam.mx (A.C. Ruiz-Fernández). Marine Pollution Bulletin 149 (2019) 110653 Available online 18 October 2019 0025-326X/ © 2019 Elsevier Ltd. All rights reserved. T