An environmental evaluation of food waste downstream management options: a hybrid LCA approach

Food waste treatment methods have been typically analysed using current energy generation conditions. To correctly evaluate treatment methods, they must be compared under existing and potential decarbonisation scenarios. This paper holistically quantifies the environmental impacts of three food waste downstream management options—incineration, composting, and anaerobic digestion (AD). Methods The assessment was carried out using a novel hybrid input–output-based life cycle assessment method (LCA), for 2014, and in a future decarbonised economy. The method introduces expanded system boundaries which reduced the level of incompleteness, a previous limitation of process-based LCA. Results Using the 2014 UK energy mix, composting achieved the best score for seven of 14 environmental impacts, while AD scored second best for ten. Incineration had the highest environmental burdens in six impacts. Uncertainties in the LCA data made it difficult determine best treatment option. There was significant environmental impact from capital goods, meaning current treatment facilities should be used for their full lifespan. Hybrid IO LCA’s included additional processes and reduced truncation error increasing overall captured environmental impacts of composting, AD, and incineration by 26, 10 and 26%, respectively. Sensitivity and Monte Carlo analysis evaluate the methods robustness and illustrate the uncertainty of current LCA methods. Major implication: hybrid IO-LCA approaches must become the new norm for LCA. Conclusion This study provided a deeper insight of the overall environmental performance of downstream food waste treatment options including ecological burdens associated with capital goods. Keywords Anaerobic digestion Incineration Composting Food waste Hybrid life cycle assessment Capital good

Detailing the impact of the Storegga Tsunami at Montrose, Scotland

The Storegga tsunami, dated in Norway to 8150$30 cal. years BP, hit many countries bordering the North Sea. Run-ups of >30 m occurred and 1000s of kilometres of coast were impacted. Whilst recent modelling successfully generated a tsunami wave train, the wave heights and velocities, it under-estimated wave run-ups. Work presented here used luminescence to directly date the Storegga tsunami deposits at the type site of Maryton, Aberdeenshire in Scotland. It also undertook sedimentological characterization to establish provenance, and number and relative power of the tsunami waves. Tsunami model refinement used this to better understand coastal inundation. Luminescence ages successfully date Scottish Storegga tsunami deposits to 8100$250 years. Sedimentology showed that at Montrose, three tsunami waves came from the northeast or east, over-ran pre-existing marine sands and weathered igneous bedrock on the coastal plain. Incorporation of an inundation model predicts well a tsunami impacting on the Montrose Basin in terms of replicate direction and sediment size. However, under-estimation of run-up persisted requiring further consideration of palaeotopography and palaeo-near-shore bathymetry for it to agree with sedimentary evidence. Future model evolution incorporating this will be better able to inform on the hazard risk and potential impacts for future high-magnitude submarine generated tsunami events

Seasonal yield and fuel consumed for domestic, organic waste collections in currently operational door-to-door and bring-type collection systems

The European Commission is tightening waste laws, and many local authorities, particularly in countries with low recycling rates, face the question of what system to introduce for the source-separate collection of food waste from householders. This study provides empirical data in form of fuel consumed and waste yield from four councils that already have source separate organic waste collections in operation. Two systems were compared: (i) door-to-door collection and (ii) bring systems where the householder walks to the bin in her/his street to drop off organic waste. Fuel consumption for the collection operation with the bring system was dramatically lower compared to the door-to-door system. Organic waste yield was constant over the observation year in the door-to-door system employing small 20- to 30-litre bins, but increased notably in the summer with the bring system that used 240-litre bins. The metric used to quantify seasonality was the summer/winter yield ratio. As commercial waste companies do not normally allow the making of data public, this is a rare opportunity to learn from collection systems currently in operation

Comparative analysis of alternating hemiplegia of childhood and rapid-onset dystonia-parkinsonism ATP1A3 mutations reveals functional deficits, which do not correlate with disease severity

Heterozygous mutations in the ATP1A3 gene, coding for an alpha subunit isoform (α3) of Na+/K+-ATPase, are the primary genetic cause for rapid-onset dystonia-parkinsonism (RDP) and alternating hemiplegia of childhood (AHC). Recently, cerebellar ataxia, areflexia, pes cavus, optic atrophy and sensorineural hearing loss (CAPOS), early infantile epileptic encephalopathy (EIEE), childhood rapid onset ataxia (CROA) and relapsing encephalopathy with rapid onset ataxia (RECA) extend the clinical spectrum of ATP1A3 related disorders. AHC and RDP demonstrate distinct clinical features, with AHC symptoms being generally more severe compared to RDP. Currently, it is largely unknown what determines the disease severity, and whether severity is linked to the degree of functional impairment of the α3 subunit. Here we compared the effect of twelve different RDP and AHC specific mutations on the expression and function of the α3 Na+/K+-ATPase in transfected HEK cells and oocytes. All studied mutations led to functional impairment of the pump, as reflected by lower survival rate and reduced pump current. No difference in the extent of impairment, nor in the expression level, was found between the two phenotypes, suggesting that these measures of pump dysfunction do not exclusively determine the disease severity. GenBank RefSeq accession numbers: ATP1A3: NM_152296.4; ATP1B1: NM_001677.3