Abstract
A model for predicting concentrations of polychlorinated dibenzo-p-dioxins and fruns (PCDD/Fs) in beef was developed and used to examine effects of concentrations of PCDD/Fs in air and soils and feeding strategy (ratio of roughage in feed) on concentrations of PCDD/F in beef. This model was constructed based on pathways involving air, soil, plant feeds (concentrates and roughage) and cattle. Three important pathways for accumulation of PCDD/Fs in plant feeds were atmospheric deposition, root uptake and air to leaf transfer. Beef biotransfer factor (BCF) was used to predict accumulation of PCDD/Fs on beef. The predicted dioxin (PCDD/Fs) in beef was 0.118 pgTEQ/g, when Japanese environ- mental situations and feeding strategy were assumed (dioxin concentration in air, 0.06 pgTEQ/m³; dioxin concentration in soil, 40 pg TEQ/g; housed feeding; ratio of roughage, 10 %). The simulation results using the model showed that higher concentrations of PCDD/Fs in air and soils increased concentrations of PCDD/F in beef. Cattle on high roughage feed produced higher contaminated beef.
