ICP-MS-based quantitative analysis of multi-elements in commonly edible products using different microwave-assisted acid extraction (MW-AAE) methods

Abstract

This study quantified 13 hazardous heavy metals in 24 edible products, sourced from Bihar, Uttar Pradesh, and West Bengal regions of India. An inductively coupled plasma-mass spectrometry (ICP-MS) was used for determining the 13 elements of ICH3D document including Class 1 (Arsenic, Cadmium, Lead), Class 2A (Cobalt, Vanadium, Nickle), Class 2B (Thallium, Palladium, Selenium, Silver), and Class 3 (Barium, Copper, Chromium). The certified reference material of 29-Analyte /IMS-102 peach leaves was used for validating the digestion procedure. The elements were extracted from food products using different microwave assisted acid extraction (MW-AAE) procedures viz. method A, B, and C under closed conditions. The ICP-MS conditions demonstrated more sensitive detection for cd (0.009 ppb), Co (0.0098 ppb), Ti (0.0049 ppb) and Ag (0.0006 ppb) and recorded more than 50 ppt (0.05 ppb) for As, Pb, Ni, V, Se and Ba with acceptable BEC levels in the linearity range of 0.1 to 2000 ppb (r2 > 0.9). The precision % RSD and the % recovery (IS: Y, Tb, Sc) for all food products was acceptable. Among the digestion methods, the method A demonstrated more superior detection to Cd, V, Ag, Cu, Ba and Cr, whilst method B detected Thallium. Both methods B and C were equally detected As and Pd. All digestions afforded Pb, Co, Ni, Th and Cu at precise levels. Amongst the elements, Hg, V, Ni, Pd, TI, Pt, and Sb were below the permissible limits whilst As, Pb, Cd, Se, Cr, Cu, Co, Ba, Mo and Ag, were above the limits. The principal component analysis for comparison of digestion procedures revealed that the method-A digestion afforded better extraction for sensitive detection, nevertheless correlation was significant for elements detection from methods A, B, and C.