Biodegradation of e-waste microplastics by Penicillium brevicompactum.

Electronic and electric waste (e-waste) management strategies often fall short in dealing with the plastic constituents of printed circuit boards (PCB). Some plastic materials from PCB, such as epoxy resins, may release contaminants, but neither potential environmental impact has been assessed nor mitigation strategies have been put forward. This study assessed the biodegradation of microplastics (1-2 mm in size) from PCB by the fungus Penicillium brevicompactum over 28 days, thus contributing to the discussion of mitigation strategies for decreasing the environmental impact of such plastics in the environment. The capacity of P. brevicompactum to induce microplastic fragmentation and degradation has been determined by the increased the number of smaller-sized particles and microplastic mass reduction (up to 75 % within 14 days), respectively. The occurrence of chain scission and oxidation of microplastics exposed to P. brevicompactum when compared with the control conditions (which occurred only after 28 days of exposure) can be observed. Furthermore, Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy performed in dried biomass put in evidence an increase in the absorption intensities in regions that could be attributed to functional groups associated with carbohydrates. The results underline the potential role of the genus Penicillium, particularly P. brevicompactum, in the biodegradation of microplastics from PCB, thus providing the basis for further exploration of its potential for e-waste bioremediation and research on the underlying mechanisms for sustainable approaches to mitigate e-waste pollution.

Understanding Interface Exchanges for Assessing Environmental Sorption of Additives from Microplastics: Current Knowledge and Perspectives.

Although the impacts of plastic pollution have long been recognized, the presence, pervasiveness, and ecotoxicological consequences of microplastic-i.e., plastic particles < 5 mm-contamination have only been explored over the last decade. Far less focus has been attributed to the role of these materials and, particularly, microplastics, as vectors for a multitude of chemicals, including those (un)intentionally added to plastic products, but also organic pollutants already present in the environment. Owing to the ubiquitous presence of microplastics in all environmental matrices and to the diverse nature of their chemical and physical characteristics, thoroughly understanding the mechanistic uptake/release of these compounds is inherently complex, but necessary in order to better assess the potential impacts of both microplastics and associated chemicals on the environment. Herein, we delve into the known processes and factors affecting these mechanisms. We center the discussion on microplastics and discuss some of the most prominent ecological implications of the sorption of this multitude of chemicals. Moreover, the key limitations of the currently available literature are described and a prospective outlook for the future research on the topic is presented.

Microplastics from agricultural mulch films: Biodegradation and ecotoxicity in freshwater systems.

The application of bio-based biodegradable mulch films in agriculture has raised environmental concerns regarding their potential impacts on adjacent freshwater ecosystems. This study investigated the biodegradation of microplastics derived from a bio-based biodegradable mulch (bio-MPs) and its acute and chronic ecotoxicity considering relevant scenarios (up to 200 and 250 mg/kg of sediment, using pristine and/or UV-aged particles), using the fungus Penicillium brevicompactum and the dipteran Chironomus riparius as model organisms, respectively, due to their ecological relevance in freshwater environments. Fourier-transform infrared spectroscopy analysis suggested changes in the fungus's carbohydrate reserves and bio-MP degradation through the appearance of low molecular weight esters throughout a 28 day biodegradation test. In a short-term exposure (48 h), C. riparius larvae exposed to pristine or UV-aged bio-MPs had up to 2 particles in their gut. Exposure to pristine bio-MPs decreased larval aerobic metabolism (<20 %) and increased neurotransmission (>15 %), whereas exposure to UV-aged bio-MPs activated larval aerobic metabolism (>20 %) and increased antioxidant defences (catalase activity by >30 % and glutathione-s-transferase by >20 %) and neurotransmission (>30 %). Longer-term (28-d) exposure to UV-aged bio-MPs did not affect larval survival and growth nor the dipteran's emergence but increased male numbers (>30 %) at higher concentrations. This study suggests that the selected agricultural bio-based mulch film is prone to biodegradation by a naturally occurring fungus. However, there is a potential for endocrine disruption in the case of prolonged exposures to UV-aged microplastics. This study emphasises the importance of further research to elucidate the potential ecological effects of these plastic products, to ensure effective management practices, and to establish new regulations governing their use.

Facemasks: An insight into their abundance in wetlands, degradation, and potential ecotoxicity.

Disposable facemasks represent a new form of environmental contamination worldwide. This study aimed at addressing the abundance of facemasks in an overlooked natural environment with high ecological and economic value - the wetlands (Ria de Aveiro, Portugal, as study case), evaluating their potential biodegradation using naturally occurring fungi and assessing the potential ecotoxicity of released microfibres on local bivalves. All masks collected within 6500 m2 area of Aveiro wetland were 100 % disposable ones (PP-based, confirmed by Fourier transform infrared spectroscopy - FTIR) with an initial abundance of 0.0023 items/m2 in Sept. 2021, which was reduced by ∼40 % in Apr. 2022 and ∼87 % in Sept. 2022, as a reflection of the government policies. Analysis of the carbonyl index (0.03 to 1.79) underlined their state of degradation, primarily due to sun exposure during low tides. In laboratory conditions, 1 mm2 microplastics obtained from new disposable facemasks were prone to biodegradation by Penicillium brevicompactum and Zalerion maritimum inferred from microplastics mass loss (∼22 to -26 % and ∼40 to 50 %, respectively) and FTIR spectra (particularly in the hydroxyl and carbonyl groups). In addition, microfibres released from facemasks induced sublethal effects on the clam, Venerupis corrugata, mostly in their UV-aged form when compared to pristine ones, characterised by a decrease in cellular energy allocation (CEA) and an increase in aerobic energy metabolism (ETS). Concomitantly, clams exposed to 1250 items/L of UV-aged microplastics (similar to field-reported concentrations) expressed greater clearance capacity, indicating a need to compensate for the potential energy unbalance. This study provides the first baseline monitoring of facemasks in wetlands while bringing new evidence on their biodegradation and ecotoxicity, considering environmentally relevant conditions and keystone organisms in such environments. Such studies require scientific attention for rapid regulatory action against this emerging and persistent pollutant, also targeting remediation and mitigation strategies considering these items under pandemic scenarios.

Interactive effects of palladium (Pd) and microplastics (MPs) on metal bioaccumulation and biological responses in the Mediterranean mussel, Mytilus galloprovincialis.

This study investigates the potential of MPs as carriers of pollutants as they can strengthen bioaccumulation of toxic metals on marine organisms. For the first time, the interaction of the metal palladium (Pd) with the widespread MPs, both with increasing concentrations in water environments from anthropogenic sources, was tested. Mytilus galloprovincialis, an important seafood product, was exposed to Pd (24 h) in two ways: water-dissolved and MPs-adsorbed, with depuration followed for 144 h. Quantification of Pd in tissues shown an accumulation 2-3 times higher (59 % of initial Pd) for mussels exposed to MPs-adsorbed Pd and higher in digestive gland than when exposed to water-dissolved Pd (25 %; higher in gills). Additionally, it was demonstrated that Pd induced oxidative stress and altered the feeding behavior of mussels. Therefore, this work support MPs as being vectors of metals (i.e. Pd) to enhance their bioaccumulation on marine organisms which highlights ecological risk of these emerging pollutants.

Metal(oid)s in plastic debris, with distinct features, from Spanish Mediterranean beaches with different anthropogenic pressure: Are these particles potential monitors for metal pollution?

Metal(oid)s concentrations have been quantified in plastic pieces collected from four beaches located in the Mediterranean coast of Spain with different characteristics (i.e. anthropogenic pressure, zone). Metal(oid)s content was also related to selected plastic criteria (i.e. color, degradation status, polymer). The selected elements were quantified with mean concentrations in the sampled plastics with the following order: Fe > Mg > Zn > Mn > Pb > Sr > As > Cu > Cr > Ni > Cd > Co. Moreover, black, brown, PUR, PS, and coastal line plastics concentrated the higher metal(oid)s levels. Local of sampling (influence of mining exploitation) and severe degradation were key factors for uptake of metal(oid)s from water by plastics as modification of surfaces strengths their adsorption capacity. Determined high levels of Fe, Pb and Zn in plastics reflected the pollution degree of the marine areas. Therefore, this study is a contribution for the potential use of plastics as pollution monitors.

Threats to sustainability in face of post-pandemic scenarios and the war in Ukraine.

As the World slowly emerged from the then-ongoing pandemic, War broke out in Europe with the invasion of Ukraine by Russia. The enduring military conflict in Ukraine has had sweeping consequences at the human, social, economic, and environmental levels, not only for the nations involved but across Europe and globally. Damaged infrastructures, severe disruption of economic activity, and forced migration have led to negative impacts on sustainability. The COVID-19 pandemic has added another layer of complexity to this already challenging situation, as the virus has further disrupted economic activity and strained healthcare systems. Herein, we examine how the intersection of war and COVID-19 affect the United Nations' 2030 Agenda for Sustainable Development. How these intersecting challenges have impacted efforts to build a more sustainable future, and how these impacts have a global reach are also assessed. The broader implications of this case for understanding the linkages between conflict, pandemics, and sustainability more generally are also considered, relating these with the United Nations' Sustainable Development Goals (SDG) Agenda for 2030.

Microplastics altered cellular responses, physiology, behaviour, and regeneration of planarians feeding on contaminated prey.

Freshwater benthic environments are among the major sinks of microplastics (MPs, < 5 mm) sourced on inland anthropogenic activities. The ecotoxicological effects of MPs on benthic macroinvertebrates have been assessed preferably in collectors, shredders, and filter-feeders, but resulting in insufficient knowledge on the potential trophic transfer and its effects on macroinvertebrates with predator behaviour such as planarians. This work evaluated the behavioural (feeding, locomotion), physiological (regeneration) and biochemical responses (aerobic metabolism, energy reserves, oxidative damage) of the planarian Girardia tigrina after consuming contaminated live prey Chironomus riparius larvae previously exposed to microplastics of polyurethane (PU-MPs; 7-9 µm in size; 375 mg PU-MPs/kg). After the feeding period (3 h), planarians consumed 20 % more contaminated prey than uncontaminated prey, probably related to increased curling/uncurling movements of larvae (that might be more appellative to planarians). Histological analysis revealed planarians' limited intake of PU-MPs, mainly detected near the pharynx. The consumption of contaminated prey (and intake of PU-MPs) did not result in oxidative damage but slightly increased the aerobic metabolism and energy reserves which show that the consumption of more prey was sufficient to cope with the potential adverse effects of internalized MPs. Moreover, no effects were observed in the locomotion of planarians in good agreement with the hypothesis of sufficient energy acquired by the exposed planarians. Despite the previous, it seems that the energy acquired was not allocated for planarians' regeneration since a significant delay in the regeneration of the auricles was observed for planarians feeding on contaminated prey. Therefore, further studies should be performed considering the potential long-term effects (i.e., reproduction/fitness) and the effects of MPs that might result from continuous feeding on contaminated prey, representing a more realistic exposure scenario.

Draft Genome Sequence of Zalerion maritima ATCC 34329, a (Micro)Plastic-Degrading Marine Fungus.

Zalerion maritima is a marine fungus that has been studied for the biodegradation of (micro)plastics. Here, we report the draft genome sequence of strain ATCC 34329, which was shown to have a size of 58.4 Mb, a GC content of 44.39%, and 10,802 predicted genes.

Current knowledge on the presence, biodegradation, and toxicity of discarded face masks in the environment.

During the first year of the COVID-19 pandemic, facemasks became mandatory, with a great preference for disposable ones. However, the benefits of face masks for health safety are counteracted by the environmental burden related to their improper disposal. An unprecedented influx of disposable face masks entering the environment has been reported in the last two years of the pandemic, along with their implications in natural environments in terms of their biodegradability, released contaminants and ecotoxicological effects. This critical review addresses several aspects of the current literature regarding the (bio)degradation and (eco)toxicity of face masks related contaminants, identifying uncertainties and research needs that should be addressed in future studies. While it is indisputable that face mask contamination contributes to the already alarming plastic pollution, we are still far from determining its real environmental and ecotoxicological contribution to the issue. The paucity of studies on biodegradation and ecotoxicity of face masks and related contaminants, and the uncertainties and uncontrolled variables involved during experimental procedures, are compromising eventual comparison with conventional plastic debris. Studies on the abundance and composition of face mask-released contaminants (microplastics/fibres/ chemical compounds) under pre- and post-pandemic conditions should, therefore, be encouraged, along with (bio)degradation and ecotoxicity tests considering environmentally relevant settings. To achieve this, methodological strategies should be developed to overcome technical difficulties to quantify and characterise the smallest MPs and fibres, adsorbents, and leachates to increase the environmental relevancy of the experimental conditions.

Effects of Polyurethane Small-Sized Microplastics in the Chironomid, Chironomus riparius: Responses at Organismal and Sub-Organismal Levels.

Freshwater provides valuable services and functions to humankind. However, macroinvertebrates that underpin the delivery of many of those ecosystem services and functions are under an additional threat caused by microplastic pollution. Chironomids are one of the most abundant groups of macroinvertebrates in these environments and the most sensitive to microplastics. This investigation addressed the effects of polyurethane (PU-MPs; 7.0-9.0 µm) on the chironomid Chironomus riparius at the organism and sub-organism levels. For this purpose, two assays were carried out: (i) addressing the effects of PU-MPs on C. riparius partial life cycle traits (larval size and emergence parameters) in a 28 d assay considering concentrations up to 750 mg/Kg, and (ii) larvae behaviour (locomotion) as well as the biochemical responses (oxidative damage, aerobic energy production, and energy reserves) in a 10 d assay considering an environmentally relevant concentration with no observed effects on C. riparius previous life history traits (no observed effect concentration; NOEC = (375 mg/kg). Exposure to PU-MPs did not affect C. riparius larval length nor cumulative and time to emergence. Conversely, when exposed to an environmentally relevant concentration for 10 days, contaminated larvae were revealed to be lighter (but not smaller nor less nutritionally affected in terms of energy reserves) and more active when foraging, which was reflected in the activation of their aerobic metabolism when assessing the electron transport chain as a proxy. Notwithstanding, PU-MPs did not originate observable energy costs, either on protein, lipid, or sugar contents on contaminated larvae, which may justify the absence of effects on larval growth and emergence. Therefore, the increased production of energy used for the locomotion and functioning of larvae was at the expense of the fraction of energy that should have been allocated for the weight of the individuals. A long-term exposure involving a multigenerational assessment would bring intel on the potential (cumulative) sub-lethal effects of PU-MPs on C. riparius fitness.

Isosorbide and 2,5-Furandicarboxylic Acid Based (Co)Polyesters: Synthesis, Characterization, and Environmental Degradation.

Poly(2,5-furandicarboxylate)s incorporating aliphatic moieties represent a promising family of polyesters, typically entirely based on renewable resources and with tailored properties, notably degradability. This study aims to go beyond by developing poly(isosorbide 2,5-furandicarboxylate-co-dodecanedioate) copolyesters derived from isosorbide (Is), 2,5-furandicarboxylic acid (FDCA), and 1,12-dodecanedioic acid (DDA), and studying their degradation under environmental conditions, often overlooked, namely seawater conditions. These novel polyesters have been characterized in-depth using ATR-FTIR, 1H, and 13C NMR and XRD spectroscopies and thermal analysis (TGA and DSC). They showed enhanced thermal stability (up to 330 °C), and the glass transition temperature increased with the content of FDCA from ca. 9 to 60 °C. Regarding their (bio)degradation, the enzymatic conditions lead to the highest weight loss compared to simulated seawater conditions, with values matching 27% vs. 3% weight loss after 63 days of incubation, respectively. Copolymerization of biobased FDCA, Is, and DDA represents an optimal approach for shaping the thermal/(bio)degradation behaviors of these novel polyesters.

Microplastics in Internal Tissues of Companion Animals from Urban Environments.

Companion animals living in urban areas are exposed to environmental contaminants, which may include microplastics. A preliminary study was conducted by collecting postmortem samples from the internal tissue (lungs, ileum, liver, kidney, and blood clots) of 25 dogs (Canis familiaris) and 24 cats (Felis catus) living in an urban environment in Porto metropolitan area, Portugal. Suspected microplastics were found in 80 samples from 35 animals (18 cats and 17 dogs), often occurring in more than one tissue of the same animal (71.4%), primarily under small sizes (50.3% as 1-10 µm). Micro-Raman spectroscopy confirmed a fraction of particles as common polymer types (e.g., polyethylene terephthalate). However, the number of particles was very low. This study highlights the possibilities of the internalization and distribution of microplastics in the internal tissues of terrestrial vertebrates.

Are mulch biofilms used in agriculture an environmentally friendly solution? - An insight into their biodegradability and ecotoxicity using key organisms in soil ecosystems.

Biobased and biodegradable plastic mulch films (aka, mulch biofilm) have emerged as a sustainable alternative to conventional plastic mulch films in agriculture, promising to reduce soil contamination with plastic residues through in situ biodegradation. However, current standards certifying biodegradable plastics cannot predict biodegradability in natural settings. The scarce studies considering the possible biodegradation and ecotoxicity of mulch biofilms in soil systems question the environmental friendliness of these alternative options. This study assessed the biodegradation of a commercially available mulch biofilm by the soil-dwelling fungus Penicillium brevicompactum (in solid culture media and soil for 15 and 28 days, respectively), and the ecotoxicological effects of mulch biofilm microplastics on the earthworm Eisenia andrei (pristine or UV-weathered, at 0.125-0.250-0.500 g/kg). Results (from microplastics' mass loss, microscopy, and FTIR spectroscopy) suggest that the presence of P. brevicompactum promotes mulch biofilm's biodegradation. Exposure to environmental concentrations of pristine biofilm microplastics (and its ingestion) increased earthworms' sensitivity to touch, induced physiological alterations, decreased energy reserves, and decreased their reproduction (>30%). Conversely, exposure to weathered biofilm microplastics slightly increased earthworms' sensitivity, as well as carbohydrate reserves,without affecting their reproduction. The tested mulch biofilm seems to be, at first sight, an environmentally friendly alternative as it presented susceptibility for biodegradation by a widespread fungus, and the absence of ecotoxicological chronic effects on a key macroinvertebrate species in soil ecosystems when considering environmental relevant concentrations and plastics weathered conditions. Notwithstanding, the obtained results highlight the need to revise current standards, as they often neglect the role of, and their chronic effects on, naturally occurring organisms.

Different faces of cigarette butts, the most abundant beach litter worldwide.

Cigarette butts (CBs) are non-biodegradable residues of synthetic origin, prevalent on beaches all over the world. The study evaluates discarded CBs on an intensely used urban beach, determining variations in physical and chemical characteristics. CBs collected were observed, classified, and visually separated according to a proposed scale of four levels of degradation to test the potential match between physical and chemical decay. CBs (un-smoked, smoked, and discarded) were used to determine the average length (cm) and mass (g) in order to observe changes in these parameters among the levels. Cigarette butts experience consecutive mass loss during environmental exposure. Scanning electron microscopy (SEM) images were obtained to assess physical changes in fibers due to smoking. FTIR-ATR was used to assess CBs new (un-smoked), smoked, and discarded samples in relation to cellulose acetate decay. The FTIR-ATR spectroscopy of the most visually degraded cigarette butts indicated modifications in the spectra when compared to un-smoked cigarettes.

A straightforward method for microplastic extraction from organic-rich freshwater samples.

The extraction of microplastics from organic-rich freshwater samples is challenging and limited information is available in the literature. This study aims at developing efficient methods for water volume reduction and organic matter removal in freshwater samples, while focusing on the reduction of the economic and environmental costs, maintaining microplastics integrity and avoiding contamination. For the water volume reduction approach, centrifuging freshwater samples (water, sediment, algae, leaves, driftwood, fish tissue) at different speeds (3500, 6000 rpm) and times (5, 10 min) showed that 3500 rpm for 5 min was efficient to settle the mineral and organic material, while preserving the polymers and showing high microplastic recovering rates (93 ± 6%). These recovery rates were significantly higher than the traditional sieving approach (77 ± 22%). The posterior minimal consumption of reagents resulting from the reduction of water volume helped to reduce the economic and environmental costs of the devised methodology, becoming more aligned with green chemistry principles. For biogenic organic matter removal, four digestion solutions were tested on freshwater samples, namely 10% potassium hydroxide, Fenton reagent (30% H2O2 + Fe(II)), 7% and 10% sodium hypochlorite (NaClO), under 3 periods of time (1, 6 and 15 h), at 50 °C. Both 7% and 10% NaClO showed the highest rates of organic matter removal (86 ± 1% and 90 ± 1%, respectively), after 6 h at 50 °C. Exposure of virgin and aged polymers (polyethylene, polypropylene, polystyrene, polyvinyl chloride, nylon, polyethylene terephthalate) to NaClO showed no weight, visual, surface structure, Fourier transform infrared spectra and carbonyl index changes, except for nylon, although not to an extent that affected its identification. This method resulted in high recovery rates of polymers (92 ± 6%). Thus, 7% NaClO at 50 °C for 6 h (or overnight) may be efficiently used for microplastic analysis in organic-rich freshwater samples.

Organic contaminants in marine sediments and seawater: A review for drawing environmental diagnostics and searching for informative predictors.

Marine ecosystems represent major sinks for persistent organic pollutants (POPs). Yet, while their regulations fit localized activity and emissions, POPs are mobile and can persist away from their source. The present review draws an environmental diagnostic of the organic substances studied over the past forty months, which ones accumulated the most, and where. Maximum reported concentration was used as a proxy for the accumulation of contaminants. POPs occurrences studied in the Jan 2018-April 2021 period were recorded into a database, along with (i) the geographical location of the sample and its coastal or offshore origin, (ii) the type of compartment analyzed (water vs sediment), as well as (iii) the POPs and the sample physical-chemical parameters reported. In the articles reviewed, maximum reported concentrations of POPs were in the ng/L range in seawater and in the µg/kg range in sediments. Some hotspots presented concentrations high enough to represent a hazard for sea organisms in the water columns (µg/L range) or in surficial sediments (mg/kg range). On a global scale, offshore (>1 km from the coast) maximum reported concentrations were, for the majority of the POPs, equivalent or higher than coastal ones. Finally, a POP solubility threshold (900 mg/L) was observed above which POPs would not be found in offshore waters, but only in sediments. This review highlights that studying POP accumulation away from their sources is fundamental for the diagnostic of long-lasting marine POPs contaminations. Further, POPs lipophilicity is a good predictor for offshore transport, and an indicator of interest for predicting sediment accumulation. Although POPs fate and transport in oceans is complex and require a finer analysis that this review could provide, the present work is a step forward identifying the hotspots in which POPs could be of particular concern, along with chemical indicators to predict for POPs accumulation in marine reservoirs.