Study Protocol: ILiFOOD Project – Lithium in Food: The Impact of Lithium Mining

Abstract

ObjectivesAlthough not yet considered an essential trace element, Li is important for humans considering that its excess/deficiency in the human body impacts cell growth, reproductive function, and neurotransmission regulation. In light of green energy, the interest in Li is growing since it is a component of electric vehicles’ batteries. Given this, the Li mining industry is prospering with a possible increase in dietary Li exposure. Li levels in soils and mineral waters vary between regions, depending on soil characteristics and environmental conditions. Thus, the same variability of the Li levels in foods can occur, especially in areas close to active Li mines. As Portugal is a country with active and prospective Li mining concessions, a research project, ILiFOOD, will be carried out between 2022 and 2023 to evaluate the impact of Li mining in surrounding subsistence farms and in the population's dietary intake.MethodsA sampling plan was designed to cover 7 locations: 3 close to active mining sites, 3 outside active mining sites, and 1 in a future mining site. Samples, collected in 12 subsistence farms per location, will include potatoes, cabbages, and tap water, each collected in 3 different sampling points per farm. In total, we will collect 252 cabbages samples, 252 potatoes samples, and 84 tap waters. Soils and irrigation water samples will also be collected. Following the protocol established for Total Diet Studies and the National Food Nutrition Survey, samples will be analyzed as pools. Li and other trace elements (Al, Ar, Bo, Be, Cd, Co, Cu, Mn, Ni, Pb, Se, Sr, Tl, St, and Zn) will be determined by inductively coupled plasma mass spectrometry and minerals (Ca, Na, Fe, K, P, and Mg) by inductively coupled plasma optical emission spectroscopy. For the risk analysis, analytical data will be complemented by a socio-demographic and food consumption survey applied to local inhabitants.Results-ConclusionsWith the project results, it will be possible to characterize the exposure of the Portuguese population, living near active mines, to Li and other elements, thus prioritizing possible needed measures to promote public health.Funding SourcesThis work is financed by national funds through FCT – Fundação para a Ciência e a Tecnologia, I.P., within the scope of the project EXPL/CTA-AMB/0977/2021.