A) lead (Pb), B) cadmium (Cd), C) arsenic (As), D) mercury (Hg) residual contents (µg/g ww) in camels’ liver, kidney, tongue, and muscle retailed in Egypt and Saudi Arabia. Columns carrying different letters (a, b, and c) are significantly different among Egyptian samples; while columns carrying different letters (A, B, and C) are significantly different among Saudi samples. Star marks refers to significant difference between Egyptian and Saudi samples, P < 0.05.