Landspreading dioxin-contaminated papermill sludge: a complex problem

Assessing the potential for human exposure and resultant health risk from applying dioxin-contaminated papermill sludge to agricultural and silvicultural lands in Central Wisconsin is a complex issue. This is an intricate problem with many facets to consider. Among the exposure and risk assumption issues discussed are application of dioxin and furan equivalency factors; acceptable daily intake levels; cancer risk levels; and exposure scenarios including food, air, dermal, and soil ingestion. The range of regulatory options run from banning any application of dioxin-contaminated sludge to establishing acceptable or tolerable contamination limits. A preliminary assessment of potential human exposure scenarios found a many thousand-fold range of risk.