Studies on Physicochemical Properties, Trace Mineral and Heavy Metal Contents of Common Energy Drinks

Ten brands of energy drinks were analyzed for their physicochemical properties (pH, turbidity, conductivity and total dissolved solids), essential and heavy metals contents. Results showed that the pH ranged from 4.47 ± 0.012 - 5.27 ± 0.017. Energy drinks analyzed all fell within the FDA recommended pH range for caffeinated drinks and coffee. Turbidity ranged from 53 ± 1.732 – 592 ± 1.155 NTU. Conductivity ranged from 497 ± 0.006 – 1975 ± 1.732 S/µcm and total dissolved solids ranged from 243 ± 0.577 – 940 ± 0.000mg/L. Iron, calcium, zinc and potassium were found in all the energy drinks. Cadmium was not detected in all energy drinks samples. The copper concentration of energy drinks ranged from 0.002 ± 0.0002 - 0.070 ± 0.0006 mg/L. All sampled energy drinks had concentrations below the maximum contaminant level (MCL) of copper (1.0 mg/L). Lead concentration of energy drinks ranged from 0.028 ± 0.0006 - 0.139 ± 0.0004 mg/L. These exceeded the maximum contaminant limit of lead (0.01 mg/L). Manganese was detected only in sample PH and has a concentration of 0.003 ± 0.0001 mg/L which is below the maximum contaminant level (MCL) of 0.05 mg/L.