Andre van den Doel

and 6 more

The 2000 European Union Water Framework Directive (WFD) states that ‘Member States shall ensure the necessary protection for the bodies of water identified with the aim of avoiding deterioration in their quality in order to reduce the level of purification treatment required in the production of drinking water’. However, it does not specify how to evaluate or quantify this level of purification treatment. The scientific literature contains several different Water Quality Indices (WQIs), but none are suited for this purpose. Therefore, we propose a novel WQI that we specifically designed to quantify the level of purification required to prepare drinking water from source water. It is based on the WQI of the Canadian Council of Ministers of the Environment (CCME WQI), which was chosen because it is widely accepted, can be used with any number of input parameters, does not require expert judgement and has been applied to assess source water quality before. We compare measured contaminant concentrations in source water to drinking water guidelines and additionally incorporate the resilience of contaminants to treatment processes in the index (which is not possible in the CCME WQI). Furthermore, we accommodate for varying sampling frequencies that are characteristic of the ongoing monitoring programme. These changes make our index more robust and sensitive to relevant changes in source water quality. We calculated index scores for source water from the Rhine and the Meuse rivers to monitor the effect of implementation of the WFD on the effort required to produce of drinking water.

Roy Spijkerman

and 9 more

Rationale Neutrophils and monocytes are key immune effector cells in inflammatory bowel disease (IBD) that is associated with chronic inflammation in the gut. Patients with stable IBD who exercise have fewer flare-ups, but no underlying mechanism has been identified. Therefore, the aim of this study was to compare the responsiveness of these innate immune cells after repeated bouts of prolonged exercise in IBD patients and controls. Methods Patients with IBD and age- and gender-matched healthy controls were recruited from a cohort of walkers participating in a 4-day walking event. Blood analysis was performed at baseline and after 3 days of walking. Responsiveness to the bacterial/mitochondrial N-Formylmethionine-leucyl-phenylalanine (fMLF) was tested in granulocytes and monocytes by measuring the expression of activation markers after adding this stimulus to whole blood Results In total 38 participants (54±12 years) were included in this study: 19 walkers with and 19 walkers without IBD. After 3 days of prolonged exercise, a significant increase in responsiveness to fMLF was observed in all participants irrespective of disease. However, IBD patients showed significantly smaller increase in neutrophils (p=0.010; p=0.030; p=0.010, respectively) and monocytes (p=0.001; p=0.008; p=0.005, respectively), compared to controls. Conclusions Increased responsiveness of neutrophils and monocyte to fMLF was demonstrated after repetitive bouts of prolonged exercise. Interestingly, this exercise was associated with relative refractoriness of both neutrophils and monocytes in IBD patients. These refractory cells might create a lower inflammatory state in the intestine providing a putative mechanism for the decrease in flare-ups in IBD patients after repeated exercise.