Carbon and water footprint for the recycling process of expanded polystyrene (EPS) post-consumer waste

[Abstract] Plastic pollution of the natural environment is ubiquitous, and around 40% of all plastic waste produced globally is used in single-use products and only 9% is recycled. From this plastic waste, expandable polystyrene single-use products pose a major problem because of its great volume and low density. To abord this issue, the authors proposed a circular economy model for EPS post-consumer waste in 2019 through a case study with the help of one local plastic manufacturer. Although the idea of promoting circularity of this waste seems a priori to have a good impact on the environment, the process to reincorporate reused and/or recycled materials under the concept of CE have economic and environmental impacts on the environment that should be measured. To understand if a recycling process is truly beneficial to the environment, first we need to do a sustainability analysis, using sustainability indicators, such as Carbon Footprint (CF) and Water Footprint (WF). The objective of the present paper is to perform a sustainability analysis of the expandable polystyrene post-consumer recycling into resin pellets using CF and WF as sustainability indicators. We proposed three case scenarios considering an artisanal recycling with 2019 (A), and 2027 proposed electricity power mix (B), industrial recycling with current 2019 electricity power mix (C) and the use of virgin PS and its destination in landfill to compare. We measured the CO2 emissions and m3 of freshwater with the help of SimaPro 9.1 software. Overall, the total CO2 emissions for the case scenarios A and B are approximately 42% and 16% higher than scenario D, but scenario C exhibits a reduction of almost 50%. For the water depletion, scenarios A and B show very higher values than those of scenario D with 536% and 534%, respectively. Important to mention that scenario B presents much better values for CF than scenario A, meaning that the increase in the share of electricity production by renewable energies can improve the sustainable production of recycled PS resin

Introduction of the Circular Economy to Expanded Polystyrene Household Waste: A Case Study From an Ecuadorian Plastic Manufacturer

[Abstract] Transition towards a more sustainable society is a complex task. The depletion of natural resources and waste generation cannot be sustained indefinitely, i.e. as waste increases, local landfills keep growing and land availability reduces. The introduction of circular economy in effective household solid waste management practices should be considered especially for third world countries, such as Ecuador. In this context, plastic recycling is an important step, particularly the case of expanded polystyrene containers that currently are single-use only and later end up in local landfills. This paper presents a methodology for recycling Expanded Polystyrene by means of a case study from an Ecuadorian Plastic Manufacturer. First, the manufacture of resin from post-consume EPS containers was demonstrated possible by the manufacturer. Second, results show that using 30% of post-consume resin in the mix produce satisfactory laboratory results and operational recycled containers.The authors would like to thank Marco Roche, Eng.; Technical Manager of Plásticos del Litoral S.A. (PLASTLIT) for its involvement and compromise in this project. This paper is supported by the National Secretary of Superior Education, Science, Technology and Innovation (SENESCYT) – INEDITA program, project “Characterization of urban household waste in Guayaquil for the classification of plastic and organic waste and reuse in local industry

Quantification and mapping of domestic plastic waste using GIS/GPS approach at the city of Guayaquil

[Abstract] A significant contributor to the waste stream is the domestic single-use plastic used in households, being the final disposal in most cases the local landfill. There is a significant opportunity to promote resource recovery and efficiency through the introduction of circular economy strategies. However, the knowledge and management of post-consumer plastic waste in the country is poor, and there is a lack of an efficient collection and sorting system. In this context, spatial information on domestic plastic waste generation (DPWG) is essential for recycling decision-making. The integration of Geographic Information Systems (GIS) and the Global Positioning System (GPS) shows an opportunity to collect, mapping, and analyse spatial DPWG issues. Thus, this paper had a double objective. The first was to assess the evolution of eight different types of plastic waste in the city’s households and their daily per capita generation between 2019 and 2021. The second objective was to provide a complete geo-referenced information on the quantities and typologies of domestic plastic waste (DPW) produced in Guayaquil and analyse how the flows have shifted throughout the years. The results showed that PET is the most generated, recording 97.76% and 100.00 % of the households who generate this type of plastic for 2019 and 2021, respectively, with an average of 13.08 and 15.13 g/day/c. Following, we had HDPE, PP and PVC occupying the second, third and fourth place for 2019 with 5.86, 3.05, 2.54 g/day/c, respectively. On the other hand, for 2021, PP (7.43 g/day/c), HDPE (5.92 g/day/c), and LDPE (3.99 g/day/c) occupied the second, third and fourth, respectively. According to the spatial maps, the DPW increment is in most of the popular zones. These popular zones are neighborhoods with a considerable quantity of population and limited basic services. Most of these people live in extreme poverty, being a possible relation between the COVID-19 lockdown and the increasement of DPW

Circular Economy of Expanded Polystyrene Container Production: Environmental Benefits of Household Waste Recycling Considering Renewable Energies

[Abstract] Plastic industry is ubiquitous worldwide, and the generation of “plastic waste” has been steadily increasing to the point of being considered a high impact pollutant. The expanded polystyrene (EPS) plastic industry aware of the issue is interested on trying recycling post-consumer material. Through a recent study made in an alliance between the private sector and the academy, the feasibility of the EPS “mechanical” recycling was proven; therefore, a possible solution through a circular economy model. The aim of the present paper was to investigate the potential environmental impacts avoided by the circular economy scenario previously developed, through a life cycle assessment (LCA) performed for the city of Guayaquil, where 64% of all the plastic manufacturing industries in the country are located. The entire life cycle of 1.00 kg of 5 × 5 inch. food containers were assessed from the production stage until its end-of-life stage: focusing on three different valorization paths, circular economy closed-loop (container-to-container) proposal with electricity share of 2019 and another with the 2027 future one, and traditional linear economy (container-to-landfill). Results showed that the scenario C that considers the recycling of post-consumer EPS waste and the electricity share proposed for 2027 have lower impacts in 14 out of 16 categories, in specific for the Land use (−31%), Ozone Depletion (−28%), Acidification (−24%) and Terrestrial and Marine Eutrophication (−21%). These results strongly suggest that the recycling of these kind of plastic waste could benefit the environment greatly

The Role of Personality in the Adoption of Pro-Environmental Behaviors through the Lens of the Value-Belief-Norm Theory

This article belongs to the Special Issue Urbanization and Environmental Sustainability[Abstract] The present study investigated citizens’ self-reported pro-environmental behaviors by adopting a survey and bootstrapping via structural equation modeling for five different personality traits. Adopting one traditional psycho-social theory, this study investigates how motivations, values, intentions, norms, and behaviors are connected by using different constructs from the value-belief-norm theory extended with external influences and three different pro-environmental behaviors, namely, waste preventer, green consumer, and avoider, and how the connections change between different personality traits from the Big Five personality test, namely, openness, extroversion, neuroticism, agreeableness, and consciousness. According to this study, personal conscience may inspire environmentally beneficial behaviors like green purchasing and waste reduction when appealing to the emotions of the general public. As a result, strengthening the population’s subjective norms requires interventions that concentrate on communication tactics to raise knowledge of penalties and obligations for communal advantages

Understanding Citizens’ Environmental Concern and Their Pro-environmental Behaviours and Attitudes and Their Influence on Energy Use

[Abstract] The analysis of the prime political ideologies that affect human behaviours and how these make people interact with their habitat is most necessary for policy making. The objective of the present research is to analyse the relationship between an individual’s political ideology and his/her environmental concern and pro-environmental behaviours and attitudes, and how these last two influences on pro-electrical consumption attitudes. To achieve the objective, we based the research on information from two surveys effectuated two years apart. A total of 3,395 household heads were interviewed (84.5% from 2019 and 15.5% from 2021). Four hypotheses were launched and only one validated through our study which proved the relationship between environmental concern and pro-electrical consumption attitudes. However, the study additionally shows a gradual decrease in environmental concern and pro-environmental behaviours and attitudes from centre ideology to the extreme left and right, being the values of the left-wing (extreme left and left-centre) higher than those of the right-wing (extreme right and right-centre). Additionally, a strong influence of environmental concern in pro-environmental behaviours and attitudes was found, meaning that environmental knowledge is necessary to develop greener attitudes and behaviours. These results shed light on citizens environmental policy preferences, making clear the discussion about the effects of political ideology on pro-environmental behaviours and attitudes

Dendritic cell deficiencies persist seven months after SARS-CoV-2 infection

Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV)-2 infection induces an exacerbated inflammation driven by innate immunity components. Dendritic cells (DCs) play a key role in the defense against viral infections, for instance plasmacytoid DCs (pDCs), have the capacity to produce vast amounts of interferon-alpha (IFN-α). In COVID-19 there is a deficit in DC numbers and IFN-α production, which has been associated with disease severity. In this work, we described that in addition to the DC deficiency, several DC activation and homing markers were altered in acute COVID-19 patients, which were associated with multiple inflammatory markers. Remarkably, previously hospitalized and nonhospitalized patients remained with decreased numbers of CD1c+ myeloid DCs and pDCs seven months after SARS-CoV-2 infection. Moreover, the expression of DC markers such as CD86 and CD4 were only restored in previously nonhospitalized patients, while no restoration of integrin β7 and indoleamine 2,3-dyoxigenase (IDO) levels were observed. These findings contribute to a better understanding of the immunological sequelae of COVID-19

SARS-CoV-2 viral load in nasopharyngeal swabs is not an independent predictor of unfavorable outcome

The aim was to assess the ability of nasopharyngeal SARS-CoV-2 viral load at first patient’s hospital evaluation to predict unfavorable outcomes. We conducted a prospective cohort study including 321 adult patients with confirmed COVID-19 through RT-PCR in nasopharyngeal swabs. Quantitative Synthetic SARS-CoV-2 RNA cycle threshold values were used to calculate the viral load in log10 copies/mL. Disease severity at the end of follow up was categorized into mild, moderate, and severe. Primary endpoint was a composite of intensive care unit (ICU) admission and/or death (n = 85, 26.4%). Univariable and multivariable logistic regression analyses were performed. Nasopharyngeal SARS-CoV-2 viral load over the second quartile (≥ 7.35 log10 copies/mL, p = 0.003) and second tertile (≥ 8.27 log10 copies/mL, p = 0.01) were associated to unfavorable outcome in the unadjusted logistic regression analysis. However, in the final multivariable analysis, viral load was not independently associated with an unfavorable outcome. Five predictors were independently associated with increased odds of ICU admission and/or death: age ≥ 70 years, SpO2, neutrophils > 7.5 × 103/µL, lactate dehydrogenase ≥ 300 U/L, and C-reactive protein ≥ 100 mg/L. In summary, nasopharyngeal SARS-CoV-2 viral load on admission is generally high in patients with COVID-19, regardless of illness severity, but it cannot be used as an independent predictor of unfavorable clinical outcome

Expression of P. falciparum var Genes Involves Exchange of the Histone Variant H2A.Z at the Promoter

Plasmodium falciparum employs antigenic variation to evade the human immune response by switching the expression of different variant surface antigens encoded by the var gene family. Epigenetic mechanisms including histone modifications and sub-nuclear compartmentalization contribute to transcriptional regulation in the malaria parasite, in particular to control antigenic variation. Another mechanism of epigenetic control is the exchange of canonical histones with alternative variants to generate functionally specialized chromatin domains. Here we demonstrate that the alternative histone PfH2A.Z is associated with the epigenetic regulation of var genes. In many eukaryotic organisms the histone variant H2A.Z mediates an open chromatin structure at promoters and facilitates diverse levels of regulation, including transcriptional activation. Throughout the asexual, intraerythrocytic lifecycle of P. falciparum we found that the P. falciparum ortholog of H2A.Z (PfH2A.Z) colocalizes with histone modifications that are characteristic of transcriptionally-permissive euchromatin, but not with markers of heterochromatin. Consistent with this finding, antibodies to PfH2A.Z co-precipitate the permissive modification H3K4me3. By chromatin-immunoprecipitation we show that PfH2A.Z is enriched in nucleosomes around the transcription start site (TSS) in both transcriptionally active and silent stage-specific genes. In var genes, however, PfH2A.Z is enriched at the TSS only during active transcription in ring stage parasites. Thus, in contrast to other genes, temporal var gene regulation involves histone variant exchange at promoter nucleosomes. Sir2 histone deacetylases are important for var gene silencing and their yeast ortholog antagonises H2A.Z function in subtelomeric yeast genes. In immature P. falciparum parasites lacking Sir2A or Sir2B high var transcription levels correlate with enrichment of PfH2A.Z at the TSS. As Sir2A knock out parasites mature the var genes are silenced, but PfH2A.Z remains enriched at the TSS of var genes; in contrast, PfH2A.Z is lost from the TSS of de-repressed var genes in mature Sir2B knock out parasites. This result indicates that PfH2A.Z occupancy at the active var promoter is antagonized by PfSir2A during the intraerythrocytic life cycle. We conclude that PfH2A.Z contributes to the nucleosome architecture at promoters and is regulated dynamically in active var genes