Solid phase extraction of PCDDs/PCDFs and dioxin-like PCBs from edible oils and fats.

We have studied the feasibility of solid phase extraction of PCDDs/PCDFs and dioxin-like PCBs from oils and fats as the first step of a sample preparation procedure that would not involve the chemical decomposition of the matrix. A few experimental setups using dual-layer columns packed with various brands of active carbon were tested. The use of a dual-layer microcolumn with AX-21 and Carboxen 1000 carbons for dioxins extraction from animal fats, vegetable oils and powdered milk gave satisfactory recoveries which met the European Union Commission Regulation 2017/644 criteria for dioxin analysis. The developed method of solid phase extraction on a dual-layer carbon column requires lower amounts of solvents and sorbents, tolerates high amounts of fat and can be used in both manual and automated sample preparation procedures. The recoveries obtained for the most toxic congeners (2,3,7,8-TCDD, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF) are within 79-119%.

Dioxin concentrations in dietary supplements containing animal oil on the Japanese market between 2007 and 2014.

We determined the concentrations of dioxins (polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like polychlorinated biphenyls) in 46 dietary supplement products, containing the oil of fish, marine mammals, or egg yolk, on the Japanese market between 2007 and 2014. Dioxins were detected in 43 of the 46 products tested at concentrations from 0.00015 to 67 pg TEQ/g. The highest concentration of dioxins was found in a shark liver oil product which varied insignificantly in five batches collected over a two-year period. The dioxin intakes from these five batches reached 2.3-2.8 pg TEQ/kg bw/day, or 58%-70%, respectively, of the Japanese tolerable daily intake (TDI) of 4 pg TEQ/kg bw/day. However, the dioxin intakes from most of the other products tested were less than 5% of the TDI. Although rare, supplements based on animal oils may contain relatively high concentrations of dioxins, leading to a substantial increase in dioxin intakes.

Occurrence and Estimated Dietary Intake of PCBs and PCDD/Fs in Functional Foods Enriched with Omega-3 from Spain.

The polychlorinated biphenyl (PCB), polychlorinated dibenzo-p-dioxin, and dibenzofuran (PCDD/F) contents of six functional foods enriched with omega-3 were characterized. All the samples analyzed showed concentration levels below the maximal levels established by Regulation EC 1259/201120. PCB concentrations were higher than those of PCDD/Fs; oil supplements were the most contaminated samples [1.8 pg of WHO-TEQ/g of lipid weight (lw)] followed by chicken eggs (1.3 pg of WHO-TEQ/g of lw), cow's milk (0.23 pg of WHO-TEQ/g of lw), biscuits (0.15 pg of WHO-TEQ/g of lw), soy milks (0.11 pg of WHO-TEQ/g of lw), and soy lecithin (0.049 pg of WHO-TEQ/g of lw). The most abundant non-dl-PCBs were PCBs 52 and 101 in cow's milk, soy products, and biscuits, while in chicken eggs and oil supplements, they were PCBs 153 and 138. PCBs 118 and 105 were the most frequent dl-PCBs in all samples. Only oil supplements presented quantifiable concentrations for almost all PCDD/Fs, OCDD and OCDF being the most abundant. The estimated daily intake was 2.7 pg of WHO-TEQ/day for chicken eggs, 0.91 pg of WHO-TEQ/day for cow's milk, 0.45 pg of WHO-TEQ/day for soy milks, and 0.44 pg of WHO-TEQ/day for biscuits. For oil supplements, it was more variable, but always higher.

Polychlorinated dibenzo-p-dioxins, dibenzofurans and dioxin-like PCBs in commercialized food products from Colombia.

Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are commonly known as dioxins and are the most toxic members of persistent organic pollutants (POPs) because present a variety of health effects especially as promoting agent of growing and transformation of cancer cells. They are bio-accumulate in humans primarily via the diet, specifically by ingestion of foods that have high lipid content which are generally associated with foods of animal origin such as oils and fats and with fishery and dairy products. In Colombia the Ministry of Health and Social Protection which is the entity responsible for surveillance food conditions, has established maximum levels for dioxins and dl-PCBs in oils from animal and vegetable origins. Oils of vegetable and animal origin represent an appreciable intake in the country thus the presence of dioxins and dl-PCBs in these materials is a matter of concern because they can bioaccumulate in fat. In this contribution the levels of PCDD/Fs and dl-PCBs in olive, soybean, fish oil, butter and shrimp consumed in Colombia were determined using HRGC-HRMS and were compared with the maximum levels permitted in oil samples according to both the Colombian and European regulations. WHO-TEQ concentrations for PCDD/Fs and dioxin like PCBs ranged from 0.24 to 1.710pgWHO-TEQ PCDD/Fg(-1) of fat and from 0.050 to 3.000pgWHO-TEQ PCBg(-1) of fat, respectively. As expected, fish oils and shrimp present the highest WHO-TEQ PCDD/Fs and dl-PCBs values followed by butter and soybean oil sample, while the olive oil shows the lowest levels. In general, the vegetable oils show levels below the limits established by both the Colombian and European regulations. The levels from soybean oil found in this study were slightly higher than the threshold established both by the Commission Regulation European Union (EU) and the Colombian legislation, while fish oils showed concentrations above the European regulations. Furthermore, shrimp exhibited values below the maximum concentration levels established by the EU and Colombian regulation.

A sensitivity analysis using alternative toxic equivalency factors to estimate U.S. dietary exposures to dioxin-like compounds.

EPA recommends sensitivity analyses when applying the toxic equivalency factor (TEF) method to evaluate exposures to dioxin-like compounds (DLCs). Applying the World Health Organization's (WHO) 2005 TEF values and estimating average U.S. daily dietary intakes of 25 DLCs from eight food categories, we estimate a toxic equivalency (TEQ) intake of 23 pg/day. Among DLCs, PCB 126 (26%) and 1,2,3,7,8-PeCDD (23%) dominate TEQ intakes. Among food categories, milk (14%), other dairy (28%), beef (25%), and seafood (18%) most influenced TEQ intakes. We develop two approaches to estimate alternative TEF values. Based on WHO's assumption regarding TEF uncertainty, Approach1 estimates upper and lower TEFs for each DLC by multiplying and dividing, respectively, its individual TEF by ± half a log. Based on compiled empirical ranges of relative potency estimates, Approach2 uses percentile values for individual TEFs. Total TEQ intake estimates using the lower and upper TEFs based on Approach1 were 8 and 68 pg TEQ/day, respectively. The 25th and 75th percentile TEFs from Approach2 yielded 12 and 28 pg TEQ/day, respectively. The influential DLCs and food categories remained consistent across alternative TEFs, except at the 90th percentile using Approach2. We highlight the need for developing underlying TEF probability distributions.