Assessment and projection of environmental impacts of food waste treatment in China from life cycle perspectives.

China produces vast amounts of food waste every year. However, the environmental impact of the current treatment of food waste and its potential for improvement are not very clear. Therefore, this study applied life cycle assessment to compare the current major treatment options for food waste and to systematically quantify the environmental impact of current and future food waste treatment in China based on the amount and treatment mode of food waste. In 2020, 125 million tons (Mt) of food waste was generated in China. Its treatment consumed 30.1 Mt oil-Eq of fossil fuels and 16.7 Mt of freshwater, and released 37.5 Mt of CO2-Eq. A promising finding was that if the proportion of food waste treated by anaerobic digestion exceeded 40% and landfilling was terminated by 2050, most impact categories would be reduced by more than 50%. Although anaerobic digestion is a potentially more environmentally friendly treatment option due to more output of energy and resources, it is worth noting that it consumed more freshwater than incineration and landfilling. Electricity consumption contributed more than 50% of the environmental burden of anaerobic digestion. Therefore, for the upstream of anaerobic digestion, China should further implement policies of waste classification and promote zero-waste cities, so that less impurities and more food waste would enter anaerobic digestion instead of landfills. Whereas downstream, the resource utilization of biogas and digestate enhance should be enhanced so as to strengthen the environmental sustainability of anaerobic digestion.

Production, Use, and Fate of Phthalic Acid Esters for Polyvinyl Chloride Products in China.

Phthalic acid esters (PAEs) are the most common plasticizers, approximately 90% of which are used in polyvinyl chloride (PVC) products, but they are also endocrine disruptors that have attracted considerable attention. The metabolism of PAEs in PVC products in China from 1958 to 2019 was studied using dynamic material flow analysis. The results showed that the total consumption of PAEs was 29.2 Mt in the past 60 years. By 2019, the in-use stocks of PAEs were 5.0 Mt. Construction materials were always in the leading position with respect to the consumption and in-use stocks of PAEs. A total PAE loss of 22.7 Mt was generated, of which 68.0% remained in waste distributed in landfills (50.1%), storage sites (5.5%), the environment (44.4%), 12.4% was eliminated during waste incineration and open burning, and 19.6% was emitted into the environment. From 1958 to 2019, 496.4, 55.6, and 3905.0 kt of PAEs were emitted into water, air, and soil, respectively. The use and waste treatment stages contributed 79.3 and 19.9% of the emissions of PAEs in the life cycle, respectively. This study systematically analyzed the metabolism of PAEs at the national level over a long-time span, providing useful information on the life cycle management of PAEs.

Simultaneous SERS detection of illegal food additives rhodamine B and basic orange II based on Au nanorod-incorporated melamine foam.

In food safety assessment, surface-enhanced Raman spectroscopy (SERS) is a novel detection method with the advantages of being fast, easy, and of high sensitivity. However, many SERS substrate synthesis methods are complex, and there are only a few studies on the simultaneous detection of multiple substances. In this study, a new, simple, low-cost SERS substrate was synthesised for the first time to simultaneously detect illegal food additives rhodamine B and basic orange II in chilli products. A lightweight, porous, and low-cost material of melamine foam (MF) was employed as the SERS synthesis template. The substrate's SERS effect on, and sensitivity to, rhodamine B and basic orange II were demonstrated. The molecular vibration and SERS enhancement mechanisms of the two target molecules were analysed by density functional theory (DFT) calculations. The results reveal that this fabricated substrate has great application potential for the supervision and testing industry.

In vivo immunogold labeling confirms large-scale chromatin folding motifs.

The difficulty in localizing specific cellular proteins by immuno-electron microscopy techniques limits applications of electron microscopy to cell biology. We found that in vivo immunogold labeling improves epitope accessibility, ultrastructural preservation and three-dimensional visualization, and allows correlated light and electron microscopy. We detected large-scale chromatin folding motifs within intact interphase nuclei of CHO cells and visualized the ultrastructure of DNA replication 'factories' labeled with GFP-proliferating cell nuclear antigen (PCNA).