LEVELS AND CONGENER PROFILES OF DIOXINS, FURANS AND DIOXIN-LIKE PCBS IN CERTAIN EGYPTIAN COW’S MILK FARMS

Abstract

Levels of polychlorinated dibenzo-p-dioxins, dibenzofurans (PCDD/Fs) and dioxin like-PCBs (dl-PCBs) were determined in thirty five pooled raw cow milk and fifty nine animal feedstuffs samples including silage, hay, cereals and other farinaceous feed, premixes and mixed feeds were consequently collected from different regions of Egypt farms [Qaliubiya, Banha, Sharkia, Monoufia, Damietta, Kafr El-Sheikh, Gharbiya, Ismailia, Port Said, Noubaria (Beheira), Fayoum and Beni Suef]. The method performance used was assessed through successfully participation in specific interlaboratory studies (food and feed) organized by European Union Reference Laboratory for Dioxins and PCBs in Food and Feed. The obtained results showed that PCDD/Fs concentrations in cow milk ranged between 1.19 and 12.48 pg WHO TEQ g-1 fat weight (FW) and in animal feed ranged between 0.08 and 1.43 pg WHO TEQ g-1 dry matter (DM), however dl-PCBs concentrations in cow milk ranged between 0.14 and 3.7 pg WHO TEQ g-1 (FW) and animal feed ranged between 0.01 and 0.38 pg WHO-TEQ g-1 (DM). The mean concentration of PCDDs/PCDFs was 0.32 pg TEQ g-1 dry matter (DM) for animal feed, this level proved to be below the maximum (EU) limits (0.75 pg WHO TEQ g-1 DM). While the level of 3.9 pg TEQ g-1 (FW) for cow milk proved to be higher than the acceptable European (EU) standards limits for milk (3 pg WHO TEQ g-1 FW). However the mean concentration of dl-PCBs was 0.05 pg TEQ g-1 (DM) for animal feed which was below the maximum (EU) limits for feed (0.5 pg WHO TEQ g-1 DM). The obtained dl-PCBs level of 0.98 pg TEQ g-1 (FW) for cow milk was below the acceptable EU standards limits for milk (3 pg WHO TEQ g-1 FW). These finding showed that animal feed have often been reported as the major source to the PCDD/Fs and dl-PCBs intake into the cow milk chain, which characterized in parallel by the total TEQ (dioxin and dl-PCBs). Data revealed that the sum of furan (TEQ) was the predominant group with contribution by 49.96 and 42.51%; followed by the sum of dioxin (TEQ) with contribution by 29.66 and 44.46%; followed by the sum of non-ortho PCBs (TEQ) with contribution by 18.1 and 11.48% and then the sum of mono-ortho PCBs (TEQ) with contribution by 2.27 and 1.54% in cow milk and animal feed, respectively. Finally, the present results indicated that the general exposure of the population in Egypt to the main highest persistent organic pollutants was carried through cow milk and animal feedstuffs intake.