Table 5 The levels of heavy metals in various khat samples cultivated in selected countries and the WHO/FAO recommended heavy metal permissible limits
From: A review of the health implications of heavy metals and pesticide residues on khat users
Heavy metal | Concentration range of heavy metal in khat samples | Country of study | WHO/FAO recommended values | References |
|---|---|---|---|---|
Pb | 0.18–0.87 mg/kg | Jazan, Saudi Arabia | 1.75 mg PTWI | Al Bratty et al. (2019) |
0.18–0.87 mg/kg | Ethiopia | 1.75 mg PTWI | Woldamanuel (2019) | |
0.97 ± 0.37 µg/g | Ethiopia | 214 µg RDA | Ashenef et al. (2014) | |
Cd | ND | Ethiopia | 2 µg/g PL | Tadesse and Kebede (2015) |
0.00–0.08 mg/kg | Jazan, Saudi Arabia | 0.49 mg PTWI | Al Bratty et al. (2019) | |
0.15 ± 0.90 µg/g | Ethiopia | 0.49 mg PTWI | Woldamanuel (2019) | |
0.87 ± 1.44 µg/g | Ethiopia | 60 µg RDA | Ashenef et al. (2014) | |
Mn | ND | Ethiopia | 0.02 µg/g PL | Tadesse and Kebede (2015) |
339.63–1284.43 mg/kg | Jazan, Saudi Arabia | 6.68 mg PTWI | Al Bratty et al. (2019) | |
11.64 ± 4.28 µg/g | Ethiopia | 2000 µg RDA | Ashenef et al. (2014) | |
Co | 0.51–1.73 mg/kg | Jazan, Saudi Arabia | 1.33 mg PTWI | Al Bratty et al. (2019) |
Cu | 254.60–1757.37 mg/kg | Jazan, Saudi Arabia | 245 mg PTWI | Al Bratty et al. (2019) |
|  | 0.10–41.80 µg/g | Ethiopia | 245 mg PTWI | Woldamanuel (2019) |
Zn | NG | Ethiopia | 10 µg/g PL | Tadesse and Kebede, (2015) |
7.17 ± 1.11 µg | Ethiopia | 3000 µg RDA | Ashenef et al. (2014) | |
351.95–1240.93 mg/kg | Jazan, Saudi Arabia | 490 mg PTWI | Al Bratty et al. (2019) | |
25.15–73.95 µg/g | Ethiopia | 490 mg PTWI | Woldamanuel (2019) | |
40.98 ± 20.2 µg | Ethiopia | 60,000 µg RDA | Ashenef et al. (2014) | |
Fe | 6.80–8.96 µg/g | Ethiopia | 50 µg/g PL | Tadesse and Kebede (2015) |
529.13 ± 350.03 µg | Ethiopia | 10,000 µg RDA | Ashenef et al. (2014) | |
33.87–59.044 µg/g | Ethiopia | 20 µg/g PL | Tadesse and Kebede (2015) |