Having discussed the negative impact Li pollution has on biodiversity, I would like to explore the benefits natural Li, Li in small amounts can have for biodiversity in this blog. Like most naturally occurring things (e.g. greenhouse effect), Li plays an important role in the healthy growth and development of humans and animals in small amounts. Li occurs naturally in small amounts in groundwater and soil (Memon et al., 2020). Although only found in small concentrations averaging between 3.8 and 46.3 μg/L (0.0005–0.0067 mmol/L) (Araya et al., 2022), Li positively impacts the health of people.
Figure 1
The benefits of naturally occurring Li include:
1. Reduces rates of suicide
Drinking water with naturally occurring Li has been found to improve the mental health of people (Memon et al., 2020). Over the years, many studies have been conducted to find the relationship between different concentrations of Li and suicide rates (Memon et al., 2020; Araya et al., 2022). Although little correlation has been found in concentrations below 30.7 μg/L (0.0044 mmol/L) in drinking water, a much stronger correlation was found between Li and suicide rate at a higher concentration from 32.9 μg/L (0.0047 mmol/L) (Araya et al., 2022). Generally, among the areas studied, areas with a higher natural concentration of Li also recorded lower rates of suicide (Forlenza et al., 2012) (Figure 2).
Figure 2: Reduce suicide levels with an increase in Li levels (Ohgami et al., 2009)
2. Mood stabilising effects
Apart from reducing rates of suicide, Li have mood stabilisation effects, independent of its anti-suicidal effect (Memon et al., 2020). This is also why despite having negative health impacts when taken in at above natural concentrations, Li continues to be used in bipolar treatment and medicine to stabilise the mood swings of patients (Forlenza et al., 2012).
3. Neuroprotective effects
Additionally, Li can improve a person’s cognitive function (Neves et al., 2020). Despite only being present naturally, in small amounts, Kessing et al. (2017) found that water with higher concentrations of Li significantly reduced dementia in Denmark. However, when used in the treatment of neurological diseases such as Alzheimer’s disease often requires a higher than the natural concentration of Li of up to 300 µg/day (Neves et al., 2020).
4. Reduces inflammation
Finally, Li is also able to reduce inflammation thanks to its ability to inhibit glycogen synthase kinase-3 (GSK3) (Beurel & Jope, 2014).
GSK3 promotes the production of inflammatory molecules and cell migration, which together make GSK3 a powerful regulator of inflammation. – Jope et al., 2007
While naturally occurring Li benefits humans, the rapid increase in Li pollution can result in Li concentration soaring exponentially in coming years if few related regulations and policies are passed and enforced. The impacts of Li in nature at a much higher concentration will no longer be just beneficial and adverse health impacts discussed in previous blogs will arise, further straining the global health system.
Reference List
Araya, P. E., Martínez, C., & Barros, J. (2022). Lithium in Drinking Water as a Public Policy for Suicide Prevention: Relevance and Considerations. Frontiers in Public Health, 10. https://doi.org/10.3389/fpubh.2022.805774
Beurel, E., & Jope, R. S. (2014). Inflammation and lithium: clues to mechanisms contributing to suicide-linked traits. Translational Psychiatry, 4(12), e488. https://doi.org/10.1038/tp.2014.129
Forlenza, O. V., De Paula, V. S., Machado-Vieira, R., Diniz, B. S., & Gattaz, W. F. (2012). Does Lithium Prevent Alzheimerʼs Disease? Drugs & Aging, 29(5), 335–342. https://doi.org/10.2165/11599180-000000000-00000
Jope, R. S., Yuskaitis, C. J., & Beurel, E. (2007). Glycogen Synthase Kinase-3 (GSK3): Inflammation, Diseases, and Therapeutics. Neurochemical Research, 32(4–5), 577–595. https://doi.org/10.1007/s11064-006-9128-5
Kessing, L. V., Gerds, T. A., Knudsen, N. N., Jørgensen, L., Kristiansen, S., Voutchkova, D. D., Ernstsen, V., Hansen, B., Andersen, P. K., & Ersbøll, A. K. (2017). Association of Lithium in Drinking Water With the Incidence of Dementia. JAMA Psychiatry, 74(10), 1005. https://doi.org/10.1001/jamapsychiatry.2017.2362
Memon, A., Rogers, I., Fitzsimmons, S. M. D. D., Carter, B., Strawbridge, R., Hidalgo-Mazzei, D., & Young, A. H. (2020). Association between naturally occurring lithium in drinking water and suicide rates: systematic review and meta-analysis of ecological studies. British Journal of Psychiatry, 217(6), 667–678. https://doi.org/10.1192/bjp.2020.128
Neves, M. G. P. M. S., Marques, J. C., & Eggenkamp, H. G. (2020). Lithium in Portuguese Bottled Natural Mineral Waters—Potential for Health Benefits? International Journal of Environmental Research and Public Health, 17(22), 8369. https://doi.org/10.3390/ijerph17228369
Ohgami, H., Terao, T., Shiotsuki, I., Ishii, N., & Iwata, N. (2009). Lithium levels in drinking water and risk of suicide. British Journal of Psychiatry, 194(5), 464–465. https://doi.org/10.1192/bjp.bp.108.055798
