Since the “Toxic Egg Event” broke out in central Taiwan, the possible sources of the high content of polychlorinated
dibenzo-p-dioxins and dibenzofuran (PCDD/Fs) in eggs have been a serious concern. In this
study, the PCDD/F contents in different media (feed, soil and ambient air) were measured. Evaluation of the impact from electric arc furnace dust treatment plant (abbreviated as EAFDT plant), which is sitespecific to the “Toxic Egg Event”, on the duck total-PCDD/F daily intake was conducted by both Industrial Source Complex Short Term model (ISCST) and dry and wet deposition models.
After different scenario simulations, the worst case was at farm A and at 200 g feed and 5 g soil for duck intake, and the highest PCDD/F contributions from the feed, original soil and stack flue gas were 44.92,
47.81, and 6.58%, respectively. Considering different uncertainty factors, such as the flow rate variation of stack flue gas and errors from modelling and measurement, the PCDD/F contribution fraction from the
stack flue gas of EAFDT plant may increase up to twice as that for theworst case (6.58%) and become 13.2%, whichwas still much lower than that from the total contribution fraction (86.8%) of both feed and original soil. Fly ashes contained purposely in duck feed by the farmers was a potential major source for the duck
daily intake. While the impact from EAFDT plant has been proven very minor, the PCDD/F content in the feed and soil, which was contaminated by illegal fly ash landfills, requires more attention.