Fertilizer-induced trace metal accumulation in barley: concentration and human health implications

In recent years, the use of fertilizers in Ethiopia has increased to boost agricultural productivity, without adequate consideration of their effect on the levels of metal accumulation in plants. Thus, in this study, the effect of fertilizers on the levels of metals in barley grains was determined, and the concentrations (mg/kg) found in barley grains were in the ranges of Fe (54.9–58.0), Zn (43–48.5), Mn (28.9–39.9), Cu (23.3–35.2), and Ni (4.9–8.8). The percentage recovery values were in the range of Fe (81.3–118%), Zn (82.7–112%), Mn (88.7–117%), Cu (80–119%), and Ni (80.3–95.6%), respectively. The target hazard quotient (THQ) and hazard index (HI) values of all metals in the four samples were less than unity, indicating that users are safe from non-carcinogenic risk with respect to metals Cu, Fe, Mn, Ni, and Zn exposure. Similarly, the incremental lifetime cancer risk was found to be less than 1 × 10− 4, indicating that there were no carcinogenic effects as a result of barley consumption. Finally, it is recommended that the effect of long-term use of fertilizers should be studied.