The Glasgow consensus on the delineation between pesticide emission inventory and impact assessment for LCA

Purpose: Pesticides are applied to agricultural fields in order to optimise crop yield and their global use is substantial. Their consideration in Life cycle assessment (LCA) is currently affected by important inconsistencies between the emission inventory and impact assessment phases of LCA. A clear definition of the delineation between the product system model (life cycle inventory, technosphere) and the natural environment (life cycle impact assessment, ecosphere) is currently missing and could be established via consensus building. Methods: A workshop held on the 11 May 2013, in Glasgow, UK, back to back with the 23rd SETAC Europe meeting had the goal of establishing consensus and creating clear guidelines where the boundary between the emission inventory and the impact characterisation model should be set in all three spatial dimensions and time when considering application of substances to an open agricultural field or in greenhouses, and consequent emissions to the natural environment and their potential impacts. More than 30 specialists in agrifood LCI, LCIA, risk assessment, and ecotoxicology, representing industry, government, and academia from 15 countries and four continents met to discuss and reach consensus. The resulting guidelines target LCA practitioners, data (base) and characterisation method developers, and decision makers. Results and discussion: Although, the initial goal was to define recommendations concerning boundaries between technosphere and ecosphere, it became clear that these strongly depend on goal and scope of an LCA study. Instead, the focus was on defining a clear interface between LCI and LCIA, capable of supporting any goal and scope requirements while avoiding double counting or exclusion of important emission flows and their potential impacts. Consensus was reached accordingly on distinct sets of recommendations for LCI and LCIA respectively, recommending for example that buffer zones should be considered as part of the crop production system and the change in yield per ha be considered. While the spatial dimensions of the field were not fixed, the temporal boundary between dynamic LCI fate modelling and steady-state LCIA fate modelling needs to be defined. Conclusions and recommendations: For pesticides application, the inventory should report: pesticide identification, crop, mass applied of each active ingredient, application method or formulation type, presence of buffer zones (y/n), location/country, application time in days before harvest and crop growth stage during application, adherence with Good Agricultural Practice (GAP), and whether the field is considered part of the technosphere or the ecosphere. Additionally, emission fractions to defined environmental media on-field and off-field should be reported. For LCIA, the directly concerned impact categories were identified as well as a list of relevant fate and exposure processes. Next steps and future work were identified: 1) establishing default emission fractions to environmental media for integration into LCI databases, and 2) interaction among impact model developers to extend current methods with new elements/processes mentioned in the recommendations, including targeted technical workshops on “how to” model specific processes.JRC.H.8-Sustainability Assessmen

Synthesis of Hyperbranched Glycoconjugates by the Combined Action of Potato Phosphorylase and Glycogen Branching Enzyme from Deinococcus geothermalis

Potato phosphorylase is able to synthesize linear polyglucans from maltoheptaose primers. By coupling maltoheptaose to butane diamine, tris(2-aminoethyl)amine and amine functionalized amine functionalized poly ethyleneglycol (PEG), new primer molecules became available. The resulting di-, tri- and macro-primers were incubated with potato phosphorylase and glycogen branching enzyme from Deinococcus geothermalis. Due to the action of both enzymes, hyperbranched polyglucan arms were grown from the maltoheptaose derivatives with a maximum degree of branching of 11%. The size of the synthesized hyperbranched polyglucans could be controlled by the ratio monomer over primer. About 60%–80% of the monomers were incorporated in the glycoconjugates. The resulting hyperbranched glycoconjugates were subjected to Dynamic Light Scattering (DLS) measurements in order to determine the hydrodynamic radius and it became obvious that the structures formed agglomerates in the range of 14–32 nm.