Challenges to evidence synthesis and identification of data gaps in human biomonitoring

The increasing number of human biomonitoring (HBM) studies undertaken in recent decades has brought to light the need to harmonise procedures along all phases of the study, including sampling, data collection and analytical methods to allow data comparability. The first steps towards harmonisation are the identification and collation of HBM methodological information of existing studies and data gaps. Systematic literature reviews and meta-analyses have been traditionally put at the top of the hierarchy of evidence, being increasingly applied to map available evidence on health risks linked to exposure to chemicals. However, these methods mainly capture peer-reviewed articles, failing to comprehensively identify other important, unpublished sources of information that are pivotal to gather a complete map of the produced evidence in the area of HBM. Within the framework of the European Human Biomonitoring Initiative (HBM4EU) initiative—a project that joins 30 countries, 29 from Europe plus Israel, the European Environment Agency and the European Commission—a comprehensive work of data triangulation has been made to identify existing HBM studies and data gaps across countries within the consortium. The use of documentary analysis together with an up-to-date platform to fulfil this need and its implications for research and practice are discussed

Purification and immobilization of engineered glucose dehydrogenase: A new approach to producing gluconic acid from breadwaste

Background Platform chemicals are essential to industrial processes. Used as starting materials for the manufacture of diverse products, their cheap availability and efficient sourcing are an industrial requirement. Increasing concerns about the depletion of natural resources and growing environmental consciousness have led to a focus on the economics and ecological viability of bio-based platform chemical production. Contemporary approaches include the use of immobilized enzymes that can be harnessed to produce high-value chemicals from waste. Results In this study, an engineered glucose dehydrogenase (GDH) was optimized for gluconic acid (GA) production. Sulfolobus solfataricus GDH was expressed in Escherichia coli. The Km and Vmax values for recombinant GDH were calculated as 0.87 mM and 5.91 U/mg, respectively. Recombinant GDH was immobilized on a hierarchically porous silica support (MM-SBA-15) and its activity was compared with GDH immobilized on three commercially available supports. MM-SBA-15 showed significantly higher immobilization efficiency (> 98%) than the commercial supports. After 5 cycles, GDH activity was at least 14% greater than the remaining activity on commercial supports. Glucose in bread waste hydrolysate was converted to GA by free-state and immobilized GDH. After the 10th reuse cycle on MM-SBA-15, a 22% conversion yield was observed, generating 25 gGA/gGDH. The highest GA production efficiency was 47 gGA/gGDH using free-state GDH. Conclusions This study demonstrates the feasibility of enzymatically converting BWH to GA: immobilizing GDH on MM-SBA-15 renders the enzyme more stable and permits its multiple reuse

From science to policy: How European HBM indicators help to answer policy questions related to phthalates and DINCH exposure

Within the European Human Biomonitoring (HBM) Initiative HBM4EU we derived HBM indicators that were designed to help answering key policy questions and support chemical policies. The result indicators convey information on chemicals exposure of different age groups, sexes, geographical regions and time points by comparing median exposure values. If differences are observed for one group or the other, policy measures or risk management options can be implemented. Impact indicators support health risk assessment by comparing exposure values with health-based guidance values, such as human biomonitoring guidance values (HBM-GVs). In general, the indicators should be designed to translate complex scientific information into short and clear messages and make it accessible to policy makers but also to a broader audience such as stakeholders (e.g. NGO's), other scientists and the general public. Based on harmonized data from the HBM4EU Aligned Studies (2014-2021), the usefulness of our indicators was demonstrated for the age group children (6-11 years), using two case examples: one phthalate (Diisobutyl phthalate: DiBP) and one non-phthalate substitute (Di-isononyl cyclohexane-1,2- dicarboxylate: DINCH). For the comparison of age groups, these were compared to data for teenagers (12-18 years), and time periods were compared using data from the DEMOCOPHES project (2011-2012). Our result indicators proved to be suitable for demonstrating the effectiveness of policy measures for DiBP and the need of continuous monitoring for DINCH. They showed similar exposure for boys and girls, indicating that there is no need for gender focused interventions and/or no indication of sex-specific exposure patterns. They created a basis for a targeted approach by highlighting relevant geographical differences in internal exposure. An adequate data basis is essential for revealing differences for all indicators. This was particularly evident in our studies on the indicators on age differences. The impact indicator revealed that health risks based on exposure to DiBP cannot be excluded. This is an indication or flag for risk managers and policy makers that exposure to DiBP still is a relevant health issue. HBM indicators derived within HBM4EU are a valuable and important complement to existing indicator lists in the context of environment and health. Their applicability, current shortcomings and solution strategies are outlined