Effects of plant zinc and plant species on plant cadmium bioavailability to animals

Many cadmium contaminated environments also contain high levels of zinc. The effects of plant Zn and plant species on plant Cd bioavailability were examined in Japanese quail fed lettuce and spinach. Four groups of birds received ;The interactions between Zn and Cd on the uptake and tissue distribution of Cd and Zn in lettuce and spinach were also examined to provide data for the plant Cd bioavailability study. Plants were grown in nutrient solution containing four Zn and four Cd levels. Results indicated that Cd and Zn in young leaves of lettuce and spinach were more closely related to the absolute and relative concentrations of Zn and Cd in solution than in old leaves or roots. Cadmium uptake to young leaves of both crops decreased with increasing solution Zn at low but not high solution Cd levels. Increasing solution Cd, increased Zn uptake to young leaves of lettuce, but not spinach.;It is concluded that combined Zn and Cd environmental pollution constitutes a lower risk of Cd transfer to humans and animals than Cd-only contamination, for those plant species in which Zn is transported readily to edible plant tissues.