Monitoring of essential and toxic elements in multi-ingredient food supplements produced in European Union

The market of food supplements (FS) in European Union (EU) is on the rise. The present study investigated the content of essential (Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Zn) and toxic elements (Cd, Cr(VI), Ni and Pb) in 168 FS produced in the EU and designed to support various health aspects (nutrition, neurological function, reproduction, weight loss, cosmetic appearance). The majority of FS did not exceed a dissolution time of 60 min in hydrochloric acid (89.8%) and phosphate buffer (85.7%). Cd and Cr(VI) were not detected in any FS, Ni and Pb were present sporadically (in 10.1 and 6.5%, respectively) at mean concentrations of 0.06 and 0.07 mg/single unit dose, respectively. All FS containing detectable Pb levels had exceeded a maximum allowance level (3.0 mg kg) set by the European Commission. Generally, the determined concentrations of essential elements fall greatly below recommended safety upper limits, except Fe in selected FS (mainly for pregnant women). Compared to the value declared on the product label, the majority of tested FS displayed mineral content below the accepted margin (70–130%). In general, the majority of the studied FS can be considered safe although discrepancies between declared and determined mineral content are worrisome. These findings are important in view of FS consumer safety.