Comparison of Heavy Metals Concentrations in Toothpaste Using Atomic Absorption Analysis and Laser-Induced Breakdown

Human health is a priority for researchers to investigate especially a toothpaste which is used daily with different types of quality. Two samples of low-quality (S1) high-quality (S2) and toothpaste were collected from the Iraqi market to be tested. This work compares two techniques, namely laser-induced breakdown spectroscopy (LIBS) and atomic absorption spectroscopy (AAS). There is a difference in sample preparation for measurement due to the two techniques. Plasma parameters such as electron temperature and electron density were calculated. Heavy metal concentrations were calculated using the calibration curve method in LIBS. After analyzing the samples, lead, zinc, mercury, nickel and cadmium were detected in the two samples, and the concentration elements were compared using the two techniques. The lead concentration was 0.3 and 0.52 in S1 and S2 toothpaste using LIBS, respectively. The concentration of mercury was 0.32 and 0.31 in S1 and S2 toothpaste using LIBS technique, respectively. Mercury appeared at a temperature of 44,800 K in sample S1 and 93,180 K in sample S2. There is a difference between the two techniques, about 15% and 10% in the first sample and 13% and 17% in the second sample for lead and mercury, respectively. These metals are dangerous to human health, so it is necessary to check these proportions due to daily use.