DISPOSITION OF TOXIC METALS IN THE AGRICULTURAL FOOD-CHAIN .2. STEADY-STATE BOVINE TISSUE BIOTRANSFER FACTORS

Steady-state oral exposure biotransfer factors for six metals, arsenic, cadmium, chromium, lead, mercury, and nickel, were calculated for three bovine tissues, muscle, liver, and kidney. Published data from both long-term feeding studies and oral bolus dose experiments were used as the primary sources of information to derive these values. This analysis indicated that the kidney exhibited the greatest bioaccumulative potential for cadmium, lead, and mercury. Very little tissue specificity was shown for arsenic and chromium. With respect to the metals studied, cadmium exhibited the greatest bioaccumulative potential (in liver and kidney), followed by mercury. The cadmium biotransfer factors for the kidney were in fact shown to be greater than analogous factors calculated for 2,3,7,8-TCDD in this tissue. Insufficient experimental data are currently available to calculate accurate biotransfer factors for nickel.