The ever-growing demand for lithium, Li, globally along with incorrect disposal and lack of standardised recycling process in the industry has resulted in Li pollution (Rodríguez et al., 2022). Water bodies are one of the most common places Li end up in through wastewater runoff (Kiyomoto et al., 2010). Being the lightest metal, the concentration of Li in the surface water naturally is very low and hence unnoticed. However, with the increase in the concentration of Li in the water bodies together with climate change, its impact on marine life can no longer be ignored.
Studies on the impact of Li on aquatic life have found that different concentrations of Li affect marine life both physiologically and biochemically (Rodríguez et al., 2022).
1. Sea urchins: Li affects the embryogenesis of sea urchins resulting in malformations (Ruocco et al., 2016, Rodríguez et al., 2022). Skeletogenic cell formation and arrangement are delayed and interrupted (Figure 1) and this percentage of abnormal embryos also increased with the concentration of LiCl (Ruocco et al., 2016) (Figure 2).
Figure 1: (Rodríguez et al., 2022)
Figure 2: (Ruocco et al., 2016)
2. Mussels: An increase in the concentration of Li decreases the metabolism of mussels (Viana et al., 2020). Furthermore, prolonged exposure to high concentrations of Li induces neurotoxic effects (Viana et al., 2020), disturbing neurons critical to the nervous system (Figure 3).
Figure 3: (Viana et al., 2020)
3. Zebrafish: Similarly, exposure to Li impacts the embryo development of Zebrafish hindering normal development and anatomy formation (Siebel et al., 2014) (Figure 4).
Figure 4: (Cebra-Thomas, 2004)
The impact of Li on marine life is likely to further exacerbate as a result of climate change (Rodríguez et al., 2022). The temperature rise of oceans raises the body temperature of ectothermic organisms which makes up the majority of marine fishes. The rise in body temperature changes the biochemical and metabolic rates of organisms (Rodríguez et al., 2022). As much marine life is already living near its physiological limits, they are likely unable to defend against the effects of Li and other pollutants as the temperature continues to rise (Rodríguez et al., 2022). Furthermore, Rodríguez et al. (2022) point out that warmer oceans increase oxidative stress as more reactive oxygen species (ROS) can now form in cells, hence leading to organisms becoming more sensitive towards pollutants.
Coupled with global warming, the increasing concentration of Li in oceans will significantly threaten the survival of marine life. Therefore, proper disposal of lithium-ion batteries and recycling facilities are necessary to reduce the amount of Li entering water bodies and this requires continuous effort and commitment from all stakeholders involved.
Reference List
Betteridge, D. J. (2000). What is oxidative stress? Metabolism, 49(2), 3–8. https://doi.org/10.1016/s0026-0495(00)80077-3
Cebra-Thomas. (2004). Effect of lithium on fish development. https://www.swarthmore.edu/NatSci/sgilber1/DB_lab/Fish/Lithium05.html
Kiyomoto, M., Morinaga, S., & Ooi, N. (2010). Distinct embryotoxic effects of lithium appeared in a new assessment model of the sea urchin: the whole embryo assay and the blastomere culture assay. Ecotoxicology, 19(3), 563–570. https://doi.org/10.1007/s10646-009-0452-9
Marín Rodríguez, B., Coppola, F., Conradi, M., & Freitas, R. (2022). The impact of temperature on lithium toxicity in the gastropod Tritia neritea. Environmental Science and Pollution Research, 29(43), 64745–64755. https://doi.org/10.1007/s11356-022-20258-2
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Ruocco, N., Costantini, M., & Santella, L. (2016). New insights into negative effects of lithium on sea urchin Paracentrotus lividus embryos. Scientific Reports, 6(1). https://doi.org/10.1038/srep32157
Siebel, A. M., Vianna, M. R., & Bonan, C. D. (2014). Pharmacological and Toxicological Effects of Lithium in Zebrafish. ACS Chemical Neuroscience, 5(6), 468–476. https://doi.org/10.1021/cn500046h
Viana, T., Ferreira, N., Henriques, B., Leite, C., De Marchi, L., Amaral, J., Freitas, R., & Pereira, E. (2020). How safe are the new green energy resources for marine wildlife? The case of lithium. Environmental Pollution, 267, 115458. https://doi.org/10.1016/j.envpol.2020.115458