Degradation of a poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) compound in different environments.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a promising biodegradable bio-based material, which is designed for a vast range of applications, depending on its composite. This study aims to assess the degradability of a PHBV-based compound under different conditions. The research group followed different methodological approaches and assessed visual and mass changes, mechanical and morphological properties, spectroscopic and structural characterisation, along with thermal behaviour. The Ph-Stat (enzymatic degradation) test and total dry solids (TDS)/total volatile solids (TVS) measurements were carried out. Finally, the team experimentally evaluated the amount of methane and carbon dioxide produced, i.e., the degree of biodegradation under aerobic conditions. According to the results, different types of tests have shown differing effects of environmental conditions on material degradation. In conclusion, this paper provides a summary of the investigations regarding the degradation behaviour of the PHBV-based compound under varying environmental factors. The main strengths of the study lie in its multi-faceted approach, combining assessments of PHBV-based compound degradability under different conditions using various analytical tools, such as visual and mass changes, mechanical and morphological properties, spectroscopic and structural characterization, and thermal behavior. These methods collectively contribute to the robustness and reliability of the undertaken work.

Consumer attitudes and concerns with bioplastics use: An international study.

The world production of plastic exceeded 360 million tonnes in 2020 alone, a considerable amount of which is not properly disposed of. The significant pressures and damages posed by conventional plastic to human and environmental health suggest that alternatives are urgently needed. One of them is "bioplastic", which is defined as bio-based plastic that is (or not) biodegradable. This paper reports on a study on the perceptions of bioplastics among consumers in 42 countries to identify their levels of information and concerns. The results suggest that most respondents have positive expectations regarding the future of bioplastics to replace conventional plastics fully or partially, especially for food containers, kitchenware, and boxes and bags for packaging. They also reported that the low costs and increased availability of bioplastic products on the market are likely to be the main drivers for their wide-scale adoption. However, many participants are unsure whether they would buy bio-based and biodegradable products if they are expensive. Overall, whereas a rather positive attitude to bioplastics has been identified, greater efforts are needed to address the many information needs of consumers towards upscaling the adoption of bioplastics. Relevant policies are therefore needed to encourage investments in the large-scale manufacture and market uptake of bioplastics. The paper reports on an initial study of consumer behavior, in a sample of countries spread across all geographical regions.

COVID-19 and waste production in households: A trend analysis.

Apart from the health aspects and the high death toll, the COVID-19 pandemic has, since its official recognition in March 2020 caused may social and economic problems. It has also led to many environmental ones. For instance, the lockdowns have led to higher levels of consumption of packaged products, and of take-away food. This paper reports on an international study on the increased consumption and subsequent changes in the amounts of waste produced since the COVID-19 pandemic. The results show that 45-48% of the respondents observed an increased consumption of packed food, fresh food, and food delivery. One of the main reasons for the increased waste generation during the lockdown was the fact that people have spent more time at home. In addition, increases of 43% and 53% in food waste and plastic packaging. Drawing from comparisons on the amount of domestic waste produced before and during the pandemic, the findings suggest that some specific types of municipal waste have visibly increased, putting additional pressure on waste management systems. This characterises one of non-intended effects of the COVID-19 pandemic. The results from this study provide useful insights to city administrations and municipal utilities on consumption patterns during emergency situations. This, in turn, may support more systemic and strategic measures to be taken, so as to curtail the increase of household waste during pandemic situations.

An assessment of attitudes towards plastics and bioplastics in Europe.

Over the last 50 years, conventional fossil-based plastics have become an integral part of our everyday lives. Apart from their low production costs, this is due to a number of their unique properties, including durability, strength, lightness, electrical and thermal insulation, resistance to chemicals and corrosion. The production of plastics has increased from 1.5 million metric tons in 1950 to 359 million metric tons in 2018. Of this total, 61.8 million metric tons were produced in Europe. There are various problems associated with plastic use and disposal that pose a serious threat to both the physical environment and human health. Since public behaviour plays a key role when it comes to the use of plastic, this paper reports on a study that focused on an assessment of attitudes towards plastics and bioplastics in Europe. The results showed that packaging is the most frequent modality of plastic used among participants. In addition, majority of participants are aware that plastic waste can affect environment and human health and therefore segregate and properly dispose plastics. Also, even though most respondents were aware of the environmental problems related to plastic use and showed a positive inclination towards using bioplastic materials, their limited availability and lack of relevant information about bioplastics pose a problem for wider use. Departing from the assumption that the public attitude is a determining factor in the consumption of plastics as a whole and bioplastics in particular, this paper also sheds some light on the current situation, identifying some trends and information gaps which should be addressed in order to encourage a more rational use of plastics in Europe.

A feasibility study of municipal solid waste incineration fly ash utilisation in Estonia.

The purpose of this paper is to discuss the alternative environmental management options for the utilisation of municipal solid waste (MSW) incineration fly ash (FA), which is generated at Iru Power Plant where MSW is incinerated in Estonia. To determine sustainable and economically feasible environmental management options for MSW incineration FA in Estonia, CO2 sequestration with a further carbonation process was examined. A partial Cost & Benefit Analysis has been conducted to compare the carbonation process to the current situation. Two carbonation options were developed. Option 1 is to use carbonated FA in any other processes based on the waste-to-product principle. Option 2 is to send carbonated FA to the non-hazardous landfill in Tallinn, Estonia. Important parameters, such as Net Present Value (NPV), Internal Rate of Return (IRR), Benefit-Cost Ratio (BCR) and Break Even Point (BEP), have been calculated for carbonation options and the current case. In addition, a sensitivity analysis has been conducted to examine its robustness. The results showed that the best option is carbonation Option 1 with NPV of 9,209,662 EUR, IRR of 43%, BCR of 2.63 and BEP between 2018 and 2019. Both Options 1 and 2 constitute more sustainable and environmentally friendly management options compared to the current situation. It can be concluded that this preliminary feasibility study showed that running a carbonation plant may be profitable and sustainable for Estonia. Currently, there is no treatment technology for MSW incineration FA in Estonia and FA is sent to a neighbouring country for further utilisation. This is the first study to demonstrate FA management options with economic and environmental benefits.

Non-deposit system option for waste management on small islands.

This paper analyses waste management on small islands (on a global scale these are micro-islands). In the context of the paper, small islands are islands that have an area less than 50 km(2) The study presents an overview of the problems connected with waste transport from islands to the mainland. Waste generation on islands is very much related to tourists. If tourists do not handle waste properly, it will cause problems. Four small Estonian islands in the range of 3-19 km(2) are studied in detail. For these and other small islands, the main problem is the waste produced by tourists, or related to tourists and waste transport to the mainland. Currently, the local municipality has to arrange and finance waste transport. In fact, and based on the polluter-pays principle, the tourists should bear the cost of waste management. There are different tax options available in order to collect the money from tourists - waste tax, harbour tax, tourist tax, donations, environmental tax and others. The study results revealed that the best possible solution for Estonian islands may be a non-deposit system - including an additional charge on ferry ticket prices. The extra money should cover the costs of waste management and waste shipping. The tourists arriving in their own boats should pay a harbour tax, which includes a waste tax to compensate for the cost of waste management.