Health risk assessment of heavy metals in basil (Ocimum basilicum L.) grown in artificially contaminated substrates
This study aimed to determine the levels of Cd, Cr and Pb in basil (Ocimum basilicum L.) cultivated on artificially contaminated substrates and to assess their potential harmful effects on human health via the calculation of the target hazard quotients (THQ). A pot experiment was performed in a completely randomized design for each tested heavy metal. It included four contamination treatments (0, 20, 50 and 100 mg kg-1 for Cd, and 0, 100, 250 and 500 mg kg-1 for Cr and Pb). Concentrations of Cd, Cr and Pb in plants samples were determined by atomic absorbtion spectroscopy. The results of this study showed that the concentrations of Cd, Cr and Pb were several times higher in roots than in the aboveground parts of basil plants regardless of contamination levels. These are desirable results because only aboveground parts of basil are used for medicinal purposes or consumption. The THQ values for Cd, Cr and Pb observed in this study were lower than 1 regardless of contamination levels, indicating that the consumption of basil from the study site (up to 10 g per day) does not pose a risk to human health from the point of view of heavy metal investigated.