Developing a Method for Trace Metal Analysis in Spices using Spectroscopic Techniques: A Review

The review assesses levels of the toxic heavy metals Cd , Pb, Cr, Hg and Fe in different spices species found in local market in Ethiopia. Heavy metal refers to any metallic chemical element that has a relatively high density and is toxic or poisonous at low concentrations. Examples of heavy metals includes: Mercury (Hg), Cadmium (Cd), Arsenic (As), Chromium (Cr), Thallium (Tl) and lead. Spice is a dried seed, fruit, root, bark or flower of a plant or a herb used in small quantities for flavor, color or as a preservative. The most commonly used methods for the sample treatment of spices are Dry ashing, Wet digestion and Microwave assisted treatment. Microwave digestion is simple, rapid and reliable for the digestion of a variety of sample matrices.