Characteristics of dioxin contamination in local market foods and health risk assessments

This study determined the concentrations of polychlorodibenzo-p-dioxins (PCDDs), polychlorodibenzofurans (PCDFs), and dioxin-like polychlorobiphenyls (dl-PCBs) in local market foods in Da Nang, Vietnam. Dioxin levels in foods were quite low. The highest average values in total toxic equivalents (∑TEQs) of PCDDs, PCDFs, and dl-PCBs were found in eggs; and decreasing in the following order: Eggs (289 fg/g fresh weight) > Seafood (171 fg/g fresh weight) > Fish (157 fg/g fresh weight) > Beef (127 fg/g fresh weight) > Chicken (71 fg/g fresh weight) > Pork (62 fg/g fresh weight) > Vegetables (17 fg/g fresh weight) > Rice (4.9 fg/g fresh weight).

The congener profiles and sources of PCDDs, PCDFs, and dl-PCBs in these foods were clarified using the principal component analysis biplots. Health risks from dioxin exposure were assessed using average daily doses through dietary intake (∑ADDF) for children and adults. ∑ADDF for adults (643–2353 fg TEQ/kg BW/day) and children aged 3 to under 16 years (517–3350 fg TEQ/kg BW/day) remained within the 90 % thresholds of tolerable daily intake (TDI) recommended by the World Health Organization. Only the highest value of ∑ADDF for children aged 1 to 3 years when consuming these local market foods (1038–4115 fg TEQ/kg BW/day) was approximately 1.15 times the upper limit of the 90 % TDI.