Environmental threats from the accumulation of plastic trash are getting worse.  It is robust, lightweight, corrosion-resistant, affordable, and durable. Microorganisms play a significant role in protecting our environment by degrading plastic wastes that are harmful either naturally or by chemical modification.  The current study aims to investigate the biodegradation of synthetic polyethylene through the utilization of a laboratory bioreactor. Various types of additives were introduced to the soil samples before subjecting them to a 30-day UV treatment. The degradation of polyethylene was shown through a reduction in weight following a 24-week incubation period with certain bacterial strains. Experimental findings have revealed that models subjected to UV radiation exhibit the highest degree of vulnerability and degradation. Approximately 52% of polyethylene (PE) films underwent degradation when exposed to soil enhanced with peat moss. In contrast, only 40% and 45% of PE films were destroyed when subjected to garden soil that was untreated and treated with UV radiation, respectively. In contrast, the addition of husk resulted in a 48% to 53% reduction in weight for PE films that were buried for the same duration of the experiment.  The highest level of effectiveness was achieved by the disintegration of the plastic material that was introduced into the soil along with organic fertilizers, resulting in a value of 56.60%. The weight loss outcomes have been substantiated by the utilization of the Atomic Force Electron Microscope (AFM) images, which exhibited the highest magnitude in the experimental model using soil supplemented with fertilizers.

Plastic pollution is a threat to the environment because of its slow degradation rate and high usage. The aim of this study is to isolate plastic degrading microorganisms from soils. The soil samples used for this study were collected from dumpsites filled with plastic and plastic materials and the effectiveness of the degradation of plastic materials was studied over a period of six (6) weeks in broth and agar culture under laboratory conditions by weight determination method. Physicochemical and microbiological analysis was carried out on the various soil samples using standard protocols. The biodegradation of polyvinylchloride (PVC) was done in-vitro using the microorganisms isolated from the soil. Microorganisms that were able to degrade a higher percentage of the plastic materials were; Staphylococcus aureus, Streptococcus sp, Bacillus sp, Escherichia coli Aspergillus niger, Aspergillus flavus and Trichoderma viridae. The total viable count for bacteria and fungi were within the range of 11.8x105 CFU/g to 2.0x1010 CFU/g and 3.3x105 CFU/g to 0.1x1011 CFU/g respectively. Staphylococcus aureus, Streptococcus sp, Bacillus sp, Micrococcus sp, Aspergillus niger, Aspergillus flavus, and Trichoderma viridae, degraded plastic up to 25%, 31.2%, 25% 31.2%, 12%, 10% and 10% respectively. These isolates may be used to actively degrade plastics, thereby reducing the rate of plastic pollution in our ecosystem.

The use of plastics as a biofilter medium is an environment-friendly and effective technology for reducing pollutants in liquid waste. The main objective is to analyze the ability of biofilters with plastic media to remove pollutants in wastewater by looking at several parameters. Various types of data were developed and analyzed to answer specific goals set through the search engines EBSCO, Scopus, and ProQuest by examining several parameters, including wastewater source, research scale, research period, temperature, media type, media thickness, and pollutant removal. The obtained data were processed to determine the distribution of the descriptions. Data related to biofiltration using plastic media was obtained from 152 articles, with only 14 articles in the search category. These findings show that all types of plastic media are effective for biofilm attachment and bacterial growth, resulting in a very large removal of pollutants present in liquid waste. Biofilters with plastic media are also known to be able to remove contaminants such as Chemical Oxygen Demand, biological oxygen demand, total organic carbon, nitrogen, phosphorus, ammonia nitrogen, hydrogen sulfide, toluene, ammonia, diethanolami, phenol, total suspended solids, and Escherichia coli. Synthetic wastewater (35.71%) was the most common wastewater source. Research related to biofiltration using plastic as the medium is mostly carried out on a laboratory scale with a total of 64.30% and using units of the day as an indicator of changes in a total of 71.42%, with an average experimental temperature of 29.1 °C.

Polyethylene terephthalate (PET) is one of the most common types of plastic waste found in municipal waste and has a negative impact on the environment, recycling and its use in concrete is an alternative solution to address these problems. The objective of the study was to evaluate the physical-mechanical behavior of hydraulic concrete with additions of PET plastic bottle fibers and natural river aggregates. The concrete was evaluated in its fresh state by means of the Slump and in its hardened state by means of density and compressive and flexural strengths, for which cylindrical and prismatic specimens were prepared with PET fibers at proportions of 2%, 4%, 6% and 8% by weight of cement plus the standard concrete designed for 21 MPa. It was found that the slump and density of the concrete decreased with additions of PET fibers. The 28-day compressive and flexural strengths increased to optimum values of 22.79 MPa and 3.19 MPa at 2% and 6% PET fibers, respectively. It is concluded that the viable application of 2 mm by 30 mm PET fibers in concrete is at 4% with dosages of 15.78 kg/m3 added to the standard concrete for structural elements subjected to compression and flexure with sustainable production at low cost.

Despite the large research effort on reporting quantities of coastal litter, the dynamics of this litter is not yet sufficiently understood. Litter inputs in five cobble beaches located in the Mediterranean (Spain) were studied over three months during winter by biweekly litter tagging. Plastic represented the dominant material that reached the beaches (77%). In remote and narrow beaches, storms constituted the main driver in litter dynamics, favouring the accumulation of floating items such as plastic bottles and wood fragments as well as the largest but contrasting effects, increasing litter inputs and outputs from the beach, respectively. In rural beaches, beach users, mainly fisher people, but also tourists, contributed to a notable input of litter to the beach. Burial and exhumation of litter were reported as common occurring processes. Better management actions are required to improve beach environmental quality. | This research is a contribution to the Andalusia PAI Research Group "RNM-328" and to the Ibero-American Beach Management and Certification Network -PROPLAYAS. This work was supported by the Biodiversity Foundation of the Ministry for the Ecological Transition and Demographic Challenge from Spain [FBIOMARINA19-01]. Special thanks go to David Saez, Natalia Sanchez, Laura Valero and Alba Amat for their help during the sampling periods and thanks to "Puertos del Estado" for oceanographic data. Thanks are also given to the municipalities involved in this research for answering to enquires about beach cleaning modalities. Finally, special thanks to two anonymous reviewers for their useful comments and suggestions, which have been very helpful in improving the manuscript.

Abandoned gillnets in the marine environment represent a global environmental risk due to the ghost fishing caused by the nets. Degradation of conventional nylon gillnets was compared to that of nets made of poly- butylene succinate co-adipate-co-terephthalate (PBSAT) that are designed to degrade more readily in the envi- ronment. Gillnet filaments were incubated in microcosms of natural seawater (SW) and marine sediments at 20 ◦C over a period of 36 months. Tensile strength tests and scanning electron microscopy analyses showed weakening and degradation of the PBSAT filaments over time, while nylon filaments remained unchanged. Pyrolysis-gas chromatography/mass spectrometry revealed potential PBSAT degradation products associated with the filament surfaces, while nylon degradation products were not detected by these analyses. Microbial communities differed significantly between the biofilms on the nylon and PBSAT filaments. The slow deterio- ration of the PBSAT gillnet filaments shown here may be beneficial and reduce the ghost fishing periods of these gillnets. | publishedVersion

Plastic ingestion has been widely investigated to understand its adverse harms on fauna, but the role of fauna itself in plastic fragmentation has been rarely addressed. Here, we review and discuss the available experimental results on the role of terrestrial and aquatic macrofauna in plastic biofragmentation and degradation. Recent studies have shown how biting, chewing, and stomach contractions of organisms shatter ingested plastic along their digestive tracts. Gut microbial communities can play a role in biodegradation and their composition can shift according to the type of plastic ingested. Shifts in molecular weights, chemical bond forming and breaking, and changes in thermal modification detected in the plastic debris present in the faeces also suggest active biodegradation. A few studies have also shown interactions other than ingestion, such as burrowing, may actively or passively promote physical plastic fragmentation by fauna. We suggest that further investigations into the role of fauna in physical fragmentation and chemical degradation linked to active ingestion and gut associated microbiota metabolism, respectively, should be conducted to better evaluate the impact of these mechanisms on the release of micro- and nano-plastic in the environment. Knowledge on macrofauna other than marine invertebrates and terrestrial soil dwelling invertebrates is particularly lacking, as well as focus on broader types of plastic polymers.

Polyethylene film is one of the most common types of recalcitrant plastic waste materials. Information regarding the fate of plastic films in soil is scarce compared to the fate of plastic films in aquatic environments. The aim of this study was to evaluate the effects of soil fauna and of impregnation of polyethylene films with oil on the colonization of low-density polyethylene films by prokaryotic communities. The field experiment was performed in a monsoon tropical forest (Vietnam). Polyethylene films were incubated in thermally pre-defaunated soil isolated from the surrounding soil by a stainless steel mesh. Three mesh sizes were used, allowing access to different size groups of soil fauna. The diversity, taxonomic structure and co-occurrence patterns in prokaryotic communities were studied using high-throughput sequencing of 16S rRNA gene libraries. The prokaryotic communities that formed on polyethylene films were slightly different from those inhabiting the surrounding soil. Contrary to our expectations, no difference in the diversity of prokaryotes was observed between microcosms with different mesh sizes. Oil impregnation also had only a minor influence on the prokaryotic community structure. Polyethylene films incubated in microcosms with soil appeared to be colonized by various consortia of prokaryotes as a barren and inert surface.

Plastic pollution is an emerging problem and is a consequence of the post-consumer plastic waste accumulation in the environment coupled to mismanaged waste programmes. Countries are counteracting the continuous growth of plastic litter with different strategies: introducing bans and limits on both plastic items and materials, promoting plastic recycling and recovery strategies and encouraging voluntary clean up actions, as well as raising public awareness. However, the toxicity of plastics to the environment and organisms is not only related to their polymer chains, but also to the fact that plastic materials contain hazardous additives and can adsorb environmental pollutants (i.e. heavy metals and persistent organic contaminants, respectively). The plastic/additives/pollutants combination may be ingested by marine organisms and then enter in the food chain. Therefore, legislation for additives and contaminants is crucial both to reduce environmental pollution and their toxic effects on organisms, which of course includes humans. In this review, the current policies on plastics and related contaminants are described focusing on current laws. Moreover, recommendations for seafood consumption are suggested, since each fish or mollusc eaten may potentially result in plastic particles, additives or contaminants ingestion.