Skip to main content

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)
  1. RDA recommended daily allowance by WHO/FAO, PTWI tolerable weekly intake, PT plant limit as per WHO, ND not detectable, NG not given