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The first investigation into PBDE levels in food produced from flood-prone land on industrial river catchments was conducted. In August 2008 samples of cows' milk, along with grass and soil were taken from 5 pairs of flood-prone and control farms on the River Trent (Central UK). The sum of 7 BDE congeners (28, 47, 99, 100, 153, 154, and 183) was calculated. Higher PBDE levels occurred in soil on flood-prone compared to control farms (median 770 vs 280 ng/kg dry weight). These higher levels were not reflected in the grass samples indicating that PBDE contamination on soils is not transferred efficiently to grass. This observation alongside the fact that cows on flood-prone farms spend time on non-flood-prone land and are fed substantial quantities of commercial feed are reasons why higher PBDE levels were not found in milk from flood-prone farms (median 300 vs 250 ng/kg fat weight). Similar BDE47/BDE99 ratios were observed in soil and grass samples compared to the PBDE product commonly used in the UK, indicating few differences in source-pathway transfer efficiencies between congeners. The BDE47/BDE99 ratio in the milk samples was greater than those in the grass and feed indicating differential food to milk transfer efficiencies between congeners.

25Mapping the distribution of crop pests and pathogens is essential to safeguard food 26 security and sustainable livelihoods. However, these data are unavailable for many 27 neglected and underutilised crops, particularly in developing countries. In Ethiopia, the 28 world's largest historic recipient of food aid, the indigenous banana relative enset (Ensete 29 ventricosum) is threatened by multiple pests and pathogens whilst providing the staple 30 starch source for 20 million people. Foremost among these is Xanthomonas Wilt of enset 31 (EXW), caused by Xanthomonas vasicola pv. musacearum (Xvm), a globally important 32 disease of bananas (Musa sp.) that likely originated in enset. Here we collate 1069 farm 33surveys to map the distribution and relative prevalence of enset pests and pathogens 34 across the entire enset growing region. We find that EXW is the most frequently 35 encountered pathogen, and that farmers consistently ranked EXW as the most significant 36 constraint on enset agriculture. Our surveys also showed that corm rot, and the pests root 37 mealybug, mole rat and porcupine are all virtually ubiquitous. Finally, we apply 38 genotyping-by-sequencing to the detection of Xvm and demonstrate that it is present even 39 in asymptomatic domesticated and wild enset samples, suggesting that management of 40 plants displaying symptoms alone may not be sufficient to reduce disease transmission. 41

In 2008-2010, samples of meat from 40 beef cattle, along with grass, soil and commercial feed, taken from ten matched pairs of flood-prone and control farms, were analysed for PCDD/Fs and PCBs. Concentrations were higher in soil and grass from flood-prone farms. The beef samples from flood-prone farms had total TEQ levels about 20% higher than on control farms. A majority of flood-prone farms (7/10) had higher median levels in beef than on the corresponding control farm. This first controlled investigation into PCDD/F and PCB contamination in beef produced on flood-prone land, presents robust evidence that flooding is a contaminant transfer mechanism to cattle raised on river catchments with a history of urbanisation and industrialisation. PCDD/F and PCB sources in these river systems are likely to be a result of the legacy of contamination from previous industrialisation, as well as more recent combustion activity or pollution events.