Baltic Sea sediments record anthropogenic loads of Cd, Pb, and Zn

Abstract

The unsustainable settlement and high industrialization around the catchment of the Baltic Sea has left records of anthropogenic heavy metal contamination in Baltic Sea sediments. Here, we show that sediments record post-industrial and anthropogenic loads of Cd, Zn, and Pb over a large spatial scale in the Baltic Sea. We also demonstrate that there is a control on the accumulation of these metals in relation to oxic/anoxic conditions of bottom waters. The total concentrations of Cd, Zn, and Pb were obtained with the near-total digestion method in thirteen cores collected from the Bothnian Bay, the Bothnian Sea, and the west and central Baltic Proper. The lowest average concentrations of Cd, Zn, and Pb were observed in Bothnian Bay (0.4, 125, 40.2 mg kg−1 DW, respectively). In contrast, the highest concentrations were observed in the west Baltic Proper (5.5, 435, and 56.6 mg kg−1 DW, respectively). The results indicate an increasing trend for Cd, Zn, and Pb from the early nineteenth century until the 1970s, followed by a decrease until 2000–2008. However, surface sediments still have concentrations above the pre-industrial values suggested by the Swedish EPA (Cd is 0.2, Zn is 85, and Pb is 31 mg kg−1 DW). The results also show that the pre-industrial Cd, Zn, and Pb concentrations obtained from 3 cores with ages < 1500 B.C. were 1.8, 1.7, and 1.2 times higher, respectively, than the pre-industrial values suggested by the Swedish EPA. To conclude, accumulations of metals in the Baltic Sea are governed by anthropogenic load and the redox conditions of the environment. The significance of correct environmental governance (measures) can be illustrated with the reduction in the pollution of Pb, Zn, and Cd within the Baltic Sea since the 1980s.

Analysis of Toxic Metal-Induced Ecological Risk in Kepez Stream, Çanakkale, Türkiye

“…Thus, since metals cannot be metabolized easily in living organisms, they accumulate in soft tissues over time and can cause serious health problems by being carried into the food chain (Saha et al, 2017). Therefore, the concentrations of elements such as Cd, Pb, Zn are frequently studied and monitored to avoid their adverse effects on ecosystem and public health (Shahabi-Ghahfarokhi et al, 2021) As all over the world, there are ecological risks arising from the accumulation of heavy metals due to human influence in the rivers and ports that are exposed to the sediment load of the rivers in Türkiye (Aksu, 1998;Bakan and Özkoç, 2007;Karadede-Akın and Ünlü, 2007;Doğan-Sağlamtimur et al, Subaşı, 2018;Varol, 2011;Ustaoğlu andTepe, 2018, 2019;Eker, 2020;Ustaoğlu et al, 2020aUstaoğlu et al, , 2020bAkarsu et al, 2022;Kükrer et al, 2022;Ustaoğlu and Islam, 2020;Ustaoğlu, 2021). These ecological risks form part of a wide variety of anthropogenic processes throughout the country during the Anthropocene (Cürebal et al, 2015).…”

Environmental impacts of shallow water mining in the Baltic Sea

“…This presents an alarming prospect regarding the vulnerability of its ecosystem. The ecological and marine health of the Baltic Sea is declining rapidly (Shahabi-Ghahfarokhi, 2022). The major problems are eutrophication, the accumulation of heavy metals, and various toxic chemicals in seabed sediments.…”