The concentration of potentially toxic elements (PTEs) in the coffee products: a systematic review and meta-analysis

Coffee is one of the most consumed products globally, and its contamination with potentially toxic elements (PTEs) occurs throughout the production chain and production. Therefore, the current meta-analysis study aimed to estimate the concentration of essential elements (Cu and Co) and the contamination of PTEs (Ni, Cr, Pb, As, and Cd) in coffee. The recommended databases, including PubMed, Scopus, and ScienceDirect, were investigated to collect data regarding the contamination of PTEs in coffee products from 2010 to 2021. Among 644 retrieved citations in the identification step, 34 articles were included in the meta-analysis. The pooled mean concentration of essential elements in coffee products is much higher than that of toxic elements (Co (447.106 µg/kg, 95% CI: 445.695–448.518 µg/kg) > Ni (324.175 µg/kg, 95% CI: 322.072–326.278 µg/kg) > Cu (136.171 µg/kg, 95% CI: 134.840–137.503 µg/kg) > Cr (106.865 µg/kg, 95% CI: 105.309–108.421 µg/kg) > Pb (21.027 µg/kg, 95% CI: 20.824–21.231 µg/kg) > As (3.158 µg/kg, 95% CI: 3.097–3.219 µg/kg) > Cd (0.308 µg/kg; 95% CI: 0.284–0.332 µg/kg)). Results showed high differences between pooled concentrations of all PTEs in coffee products of different countries.