These regulations succeeded in reducing dioxin stack emissions from incinerators. Dioxin, PCBs and chlordane are also present. Emissions of both carbon monoxide, carbon dioxide and dioxin have decreased. Studies of household waste burning indicate consistent increases in dioxin generation with increasing PVC concentrations. Most of the improvement in U.S. dioxin emissions has been for large-scale municipal waste incinerators. This unexpected side effect may make the substance useful in treating victims of dioxin poisoning. Zero discharge now', referring to discharges of heavy metals, PCBs, phenols, and dioxin. The AMA stated that there was no evidence of adverse consequences from low-level dioxin exposure. However there has been some uncertainty on the causal link between Agent Orange/dioxin exposure. Thus, the controlled combustion of waste accounted for 41.7% of the total dioxin inventory. In 2005, the first U.S.-Vietnam workshop on remediation of dioxin was held. This permits measuring dioxin burden by analysing breast milk. In particular, the city produces ninety-two percent of Italy's dioxin.