Dietary intake of dioxins and dioxin-like PCBs by residents at two typical sites in China: A review

Abstract

Polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are referred to as dioxin-like compounds due to their structural similarity. There have been increasing concerns about dioxin-like compounds because they are highly toxic and persistent compounds that may be harmful to human health and the environment. PCDD/Fs and dl-PCBs can be unintentionally produced as byproducts from certain thermal processes such as waste incineration, metal smelting and open burning as well as from manufacture of certain chemicals and pulp and paper production. They can also be found in electrical equipment containing polychlorinated biphenyls (PCBs). PCDD/Fs and dl-PCBs released in the environment can accumulate in the food chain. Human exposure to PCDD/Fs and dl-PCBs mainly through the dietary intake. This paper presents an overview on the available literatures on PCDD/F and dl-PCB levels in foodstuffs at dioxin-like compound polluted sites in China. Although various dioxin-like compound sources in China have been reported and relatively high levels of PCDD/Fs and dl-PCBs were found in the environmental matrices near dioxin-like compound sources, data on PCDD/F and dl-PCB concentrations in foodstuffs in dioxin-like compound polluted areas in China were relatively few. PCDD/Fs and dl-PCBs were found higher levels in the foodstuffs at E-waste recycling sites such as Taizhou in Zhejiang Province and Guiyu in Guangdong Province than the control areas. Moreover, higher levels of PCDD/Fs were also found in foodstuffs in Ya-Er lake than the control area because the water of Ya-Er lake had been continuously polluted by a chemical factory situated on the bank of the lake. It is estimated that dietary intake of PCDD/Fs and dl-PCBs by the residents at the two typical dioxin-like compound polluted sites exceeded the international limits and were also higher than the average consumer dietary intake of PCDD/Fs and dl-PCBs in China. It indicates that the residents at the two typical dioxin-like compound polluted sites in China may have health risks. Therefore, more attention should be attracted on the human health risks at dioxin-like compound polluted areas in China. Large scale investigation on PCDD/F and dl-PCB levels in foodstuffs in various dioxin-like compound polluted areas in China is needed to be conducted.