RESUMO
Bioplastics derived from organic materials other than crude oil are often suggested as sustainable solutions for tackling end-of-life plastic waste, but little is known of their ecotoxicity to aquatic species. Here, we investigated the ecotoxicity of second and third generation bioplastics toward the freshwater zooplankton Daphnia magna. In acute toxicity tests (48 h), survival was impacted at high concentrations (g.L-1 range), within the range of salinity-induced toxicity. Macroalgae-derived bioplastic induced hormetic responses under chronic exposure (21 d). Most biological traits were enhanced from 0.06 to 0.25 g.L-1 (reproduction rate, body length, width, apical spine, protein concentration), while most of these traits returned to controls level at 0.5 g.L-1. Phenol-oxidase activity, indicative of immune function, was enhanced only at the lowest concentration (0.06 g.L-1). We hypothesise these suggested health benefits were due to assimilation of carbon derived from the macroalgae-based bioplastic as food. Polymer identity was confirmed by infra-red spectroscopy. Chemical analysis of each bioplastic revealed low metal abundance whilst non target exploration of organic compounds revealed trace amounts of phthalates and flame retardants. The macroalgae-bioplastic disintegrated completely in compost and biodegraded up to 86 % in aqueous medium. All bioplastics acidified the test medium. In conclusion, the tested bioplastics were classified as environmentally safe. Nonetheless, a reasonable end-of-life management of these safer-by-design materials is advised to ensure the absence of harmful effects at high concentrations, depending on the receiving environment.
Assuntos
Plásticos , Poluentes Químicos da Água , Animais , Plásticos/química , Polímeros , Biopolímeros/farmacologia , Metais/farmacologia , Testes de Toxicidade Aguda , Daphnia , Poluentes Químicos da Água/toxicidadeRESUMO
Collaborative adaptive management is a process for making decisions about the environment in the face of uncertainty and conflict. Scientists have a central role to play in these decisions. However, while scientists are well trained to reduce uncertainty by discovering new knowledge, most lack experience with the means to mitigate conflict in contested situations. To address this gap, we drew from our efforts coordinating a large collaborative adaptive management effort, the Sierra Nevada Adaptive Management Project, to offer advice to our fellow environmental scientists. Key challenges posed by collaborative adaptive management include the confusion caused by multiple institutional cultures, the need to provide information at management-relevant scales, frequent turnover in participants, fluctuations in enthusiasm among key constituencies, and diverse definitions of success among partners. Effective strategies included a dedication to consistency, a commitment to transparency, the willingness to communicate frequently via multiple forums, and the capacity for flexibility. Collaborative adaptive management represents a promising, new model for scientific engagement with the public. Learning the lessons of effective collaboration in environmental management is an essential task to achieve the shared goal of a sustainable future.
Assuntos
Conservação dos Recursos Naturais , Comportamento Cooperativo , Tomada de Decisões , Humanos , Pesquisadores , IncertezaRESUMO
BACKGROUND: Single-use personal protective equipment (PPE) has been essential to protect healthcare workers during the COVID-19 pandemic. However, intensified use of PPE could counteract the previous efforts made by the UK NHS Trusts to reduce their plastic footprint. DESIGN AND METHODS: In this study, we conducted an in-depth case study in the Royal Cornwall Hospitals NHS Trust to investigate plastic-related issues in a typical NHS Trust before, during and after the pandemic. We first collected hospital routine data on both procurement and usage of single-use PPE (including face masks, aprons, and gowns) for the time period between April 2019 and August 2020. We then interviewed 12 hospital staff across a wide remit, from senior managers to consultants, nurses and catering staff, to gather qualitative evidence on the overall impact of COVID-19 on the Trust regarding plastic use. RESULTS: We found that although COVID-19 had increased the procurement and the use of single-use plastic substantially during the pandemic, it did not appear to have changed the focus of the hospital on implementing measures to reduce single-use plastic in the long term. We then discussed the barriers and opportunities to tackle plastic issues within the NHS in the post-COVID world, for example, a circular healthcare model. CONCLUSION: investment is needed in technologies and processes that can recycle and reuse a wider range of single-use plastics, and innovate sustainable alternatives to replace single-use consumables used in the NHS to construct a fully operational closed material loop healthcare system.