No abstract

Within the scope of a joint project to study soil-to-plant carryover of polyfluorinated compounds (PFCs), five cultivated plants (spring wheat, oats, potatoes, maize, and perennial ryegrass) were sown or planted in Mitscherlich pots. Six variants per species were used, each with a different concentration level of PFOA and PFOS (from 0.25 to 50 mg/kg as aqueous solution) to detect possible concentration dependence in the transfer of these two PFCs from soil to plant. PFOA and PFOS were detected by liquid chromatography-tandem mass spectrometry after appropriate sample preparation (partial drying, mincing, homogenizing, extraction). Since PFOA and PFOS presently represent the most widely studied PFCs, they are classified as "leading compounds." The results show that concentrations of PFOA/PFOS in the plants vary greatly, depending on the concentrations applied to the soil. PFOA values were higher than PFOS values in all plants except potatoes, in which these differences could be quite substantial. From the results presented here it can be seen that uptake and storage are much more intensive in the vegetative portion of the plant than relocation in the storage organs. This is particularly evident from the the comparison of concentrations found in the grain and ear and those in the straw or rest of the plant in spring wheat, oats, and maize. Transfer from "soil to crops" provides a possible explanation for the presence of PFCs in foodstuffs and in human body fluids such as blood, plasma, serum, or breast milk. The aim of the present study was to determine whether a statistically significant, concentration-dependent carryover of PFOA and PFOS in crop plants can take place, which would provide a potential entrance point for these substances into the food chain.

No abstract

In case of an outbreak of a foodborne disease, administrative decisions in the context of crisis management are only efficient if they follow standard practices and are specifically adapted to the outbreak situation in a timely manner. These goals are hard to achieve. The complexity of national and global trade structures obscures a clear view of trade flows and, consequently, it is often impossible to unravel complex trade links quickly. Furthermore, increasing public concerns about possible health hazards caused by global trade put additional pressure on decision makers. The aim of this paper was to unveil the specific trade structures of the German milk supply chain, to highlight how these structures could affect the spatial spread of a hypothetical contaminant, and to quantify the risk of the contaminant reaching the consumer. To achieve this goal, the vertical and horizontal trade links between milk producers, dairies, and consumers were taken into account. The horizontal flow of milk between dairies (inter-dairy trade), which is intended to compensate a temporary over-or undersupply of milk, is of special importance in this respect. We hypothesized that the extent of interdairy trade would significantly influence the spatial spread of contaminated milk and the contamination risk. This hypothesis was tested using a computer simulation model that predicts the hypothetical spread of a contaminant via trade of milk. The model parameters were estimated using trade data collected in 2004 and 2010. The results of our study indicate that inter-dairy trade significantly influenced the contamination risk. Compared with a scenario with no inter-dairy trade, the risk that contaminated milk will reach the consumer was up to 4 times higher, even with moderate inter-dairy trade. The contamination risk depended on the extent of inter-dairy trade in a nonlinear way and reached its maximum asymptotically when inter-dairy trade increased. The contamination risk exhibited considerable spatial variation, which could be utilized to implement more accurate food control interventions in times of crisis caused by a foodborne disease.