Absorption

Kinetic studies of cobalt absorption by excised roots of barley (Hordeum vulgare L.) exhibited a Q10 of 2.2 in a concentration range of 1 to100 µM CoCl₂. It has been suggested that a number of carrier sites are available, which are concentration dependent (24). Entry of divalent cations in the roots of maize is accompanied by a decrease in the pH of the incubation media and of the cell sap and also a decrease in the malate content (25). The uptake by different species probably depends on the various physiological and biological needs of the species (26,27).

Accumulation of cobalt by forage plants has been studied in wetlands, grasslands, and forests close to landfills and mines (11,28,29). Irrigation with cobalt-rich water in meadows has shown high intake of cobalt, which was also demonstrated in the blood serum and plasma of bulls fed on the hay grown in the field (29). African buffalos (Syncerus caffer Sparrman) in the Kruger National Park (KNP) downwind of mining and refining of cobalt, copper, and manganese showed the presence of the metals in liver in amounts related significantly to age and gender differences (30).