Determination of the concentration of heavy metals in infused teas and their assessment of potential health risk in Kashan, Iran

Tea was known as one popular and power-consuming beverage. The purpose of the current study was to determine the concentration of heavy metals in infused tea consumed in Kashan City. This cross-sectional study was carried out on 29brands of dry tea purchased from Kashan city stores. The samples were placed under acidic digestion based on the cited method in the standard method. Measuring heavy metals such as chromium, cadmium, copper, nickel, lead, arsenic, zinc, and iron was performed through ICP-OES device.SPSS16 and Excel software was used to evaluate the statistical parameters. The evaluation carcinogenic risk was performed using related formula. The obtaining results indicated that mean concentration of heavy metals in infused black tea were related to iron, zinc, copper, lead, nickel, chromium, cadmium, arsenic which was equal to 0.819 +/- 0.139, 0.419 +/- 0.314, 0.173 +/- 0.107, 0.125 +/- 0.103, 0.097 +/- 0.078, 0.059 +/- 0.061, 0.045 +/- 0.064, 0 mg/kg, respectively. According to their associated potential health risk assessment, HQ of some heavy metals including Cd, Pb, Cr, Ni, Cu, Zn, Fe and As was 0.642, 0.51, 0.2806, 0.0692, 0.0618, 0.0199, 0.0167 and 0 mg/kg-day and THQ or HI was upper than one(1.601).The results of the present study revealed that the concentration of copper, zinc and arsenic metals in all samples of infused tea was considered standard, but the concentration of lead, chromium, cadmium and nickel elements in some samples and the concentration of iron in all studied samples exceeded the maximum permissible limit presented by Iran National Standard and WHO. In addition, risk assessment analysis indicated that the consumption of the studied black tea on average(1 litre per day) had no adverse effect on the health of tea consumers.so, continuous monitoring of the concentration of heavy metals in black tea samples is essential.