Macroelement, trace element, and toxic metal levels in leaves and infusions of yerba mate (Ilex paraguariensis).

Mate is an infusion made from the dried leaves of yerba mate (Ilex paraguariensis). Yerba mate may be an important source of essential elements but could contain toxicologically relevant metals. Macroelements (Ca, Mg, Na, K), trace elements (B, Ba, Sr, V, Li, Ni, Fe, Zn, Cu, Cr, Co, Mn, Mo), and toxic metals (Al, Cd, Pb) content have been determined in 32 samples of yerba mate by ICP-OES (inductively coupled plasma-optical emission spectrometry) with the aim of determining the element content of yerba mate leaves and the influence of temperature in the extraction of these elements from the plant to the infusion, and estimating the dietary intake for each element studied. The highest element contents have been found in infusions prepared with hot distilled water (70-75 °C); the most noteworthy are K (303 mg/L), Mn (4.85 mg/L), and Al (4.52 mg/L). The consumption recommended by the producers (500 mL infusion/day) contributes significantly to the daily intake of essential elements such as Mn, Mg, and Cu. This consumption does not pose a health risk, although it is necessary to assess the risk/benefit of Ni intake from mate consumption for people with impaired renal function (500 mL/day accounts for 52.2% of the TDI).