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Microplastics (MPs) are one of the major substantial pollutants in the environment and are stored in sediments worldwide, especially in marine environments. This study shed light on the abundance, distribution, sources and chemical composition of MPs present in the surface sediments collected from the shelf part of the southeast coast of India, Bay of Bengal. A total of twenty-seven surface sediment samples were collected to study MPs pollution. The abundance and morphological characteristics of MPs were determined by counting using an Olympus SXZ7 stereo microscope. Raman spectroscopy analysis was used to identify the polymer type of the MPs. The average abundance of MPs in the study area is 460±275 MPs/kg in dry sediment. Regarding colour, transparent particles were predominant (46.42%), followed by blue, green, brown, etc. With respect to particle shape and size, fibres and 500-µm sized MPs are abundant. Polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), high-density polyethylene (HDPE), low-density polyethylene (LDPE) and polystyrene (PS) are the polymer types characterised in the study area. The higher abundance of MPs in the study area can be attenuated to human interruptions, viz., tourism, fishing and inappropriate sewage disposal in the marine environment. In addition to this, population density also plays an important role in providing MPs to the marine environment. This study provides the most valuable data to extrapolate the research for mitigating MP pollution in oceans. It also informs mankind about their disastrous activities on the marine environment, which is expected to recuperate quickly and negatively impact human health and the functionality of the marine system. [ABSTRACT FROM AUTHOR]

Microplastics, an emerging contaminant, are widespread in oceans around the world, and rivers are the key conveyors of these pollutants into the oceans. There exists a dearth of available data pertaining to seasonal fluctuation, spatial distribution and risk assessment of microplastics in rivers extending from upper reaches to the lower reaches. The collection of such data is of utmost importance for the purpose of formulating beneficial management strategies for riverine microplastics. In order to bridge this research gap, an investigation was made in the Periyar River in Kerala, India, which is exposed to anthropogenic stress and is at risk of microplastic pollution. A total of eighteen sites (six sites each from downstream, midstream and upstream) along the 244 km of the river were investigated across three seasons in a year. The study revealed a discernible pattern in the spatial distribution of microplastic concentrations, wherein there was a rise in abundance from the upstream to midstream and then a sudden increase of abundance along the downstream regions towards the lower reaches. The highest mean microplastic abundance of 124.95 items/L was obtained during the monsoon season followed by post-monsoon season i.e. 123.21 items/L and pre-monsoon i.e. 120.50 items/L. The predominant forms of microplastics were found to be fibres, fragments and filaments. Most prevalent polymer types acquired were polyethylene (PE) and polypropylene (PP). Pollution hazard index (PHI) and pollution load index (PLI) were also evaluated to assess the water quality of this river. The findings of this study conclude that the Periyar River is polluted with microplastics throughout its course and offer significant insights into the detection of microplastic origins in river systems and lend support to the implementation of potential measures aimed at mitigating their impact. [ABSTRACT FROM AUTHOR]

Microplastics (MPs) are gaining global attention in recent years due to its widespread distribution and potential health impacts. The present study focuses on the distribution and characterisation of microplastics in the sediments and its transfer into the organisms living in Kavvayi and Kumbla backwaters of Northern Malabar region, Kerala, India. MP isolation procedures including density separation, organic matter digestion, and membrane filtration followed by visual and spectral analyses using optical microscope and confocal Raman spectroscopy have been utilised for the microplastic evaluation. Microplastics of size range up to 1 μm was analysed, and the presence of MPs was detected in all samples with an average abundance of 99.5 ± 69.43 particles/kg and 96.57 ± 29.96 particles/kg in Kavvayi and Kumbla backwaters respectively. Raman spectral analysis confirmed that almost 50% of MPs to be synthetic elastomers with the remaining half encompassed by polyamide, polyethylene, polyester, polyurethane, and polypropylene. Higher abundance of MPs in the edible aquatic organisms like clams, prawns, and fishes confirmed the transfer of MP from the environment into living organisms envisages the need of further investigation on toxicological impacts and management strategies. [ABSTRACT FROM AUTHOR]

Microplastic has emerged as a global threat owing to its chronic ubiquity and persistence. Microplastics' small size expedites their ingestion at each trophic level causing biomagnification and bioaccumulation, which has raised public concerns. The present study isolated, quantified and characterized the abundance, shape, size, color, and chemical composition of the microplastics from water and sediments of the Hirakud Reservoir through a scanning electron microscope and FTIR. The ecological risk associated with the microplastics was assessed using the species sensitivity distribution (SSD) method to derive the Predicted No-Effect Concentration (PNEC) value and risk quotient (RQ). The abundance of microplastics in the surface water and sediments of the Hirakud Reservoir was estimated at 82-89 particles/L and 159-163 particles/kg, respectively. Fiber-shaped microplastics dominated both surface water (46.21%) and sediment samples (44.86%). Small-sized microplastics (53-300 μm) prevailed in all samples. Color delineation exhibited an abundance of transparent microplastics. Chemical characterization indicated the dominance of polypropylene (38%), followed by high-density polyethylene, low-density polyethylene, and polystyrene. The calculated PNEC value was 3,954 particles/m³, and the RQ was estimated to be 0.02073-0.04122 indicating negligible ecological risk to freshwater species in all the sampling sites. [ABSTRACT FROM AUTHOR]

Vegetable oils are a highly promising alternative to produce various lubricants, owing to their biodegradability and eco-friendliness. In comparison to mineral oil, these oils possess a higher flash point and viscosity index, along with superior lubricating properties. Additionally, most of the vegetable oils are easily accessible in local markets in India. However, their industrial application is limited by poor thermal and oxidative stability, which can be addressed through chemical modification, the addition of appropriate additives, or by blending these oils. Greases, characterized by their semi-solid consistency, are widely used lubricants. Most of the grease production is based on mineral oils as base oil and lithium soap as a thickener. These materials are not only non-biodegradable but also scarce and have health implications. Consequently, biodegradable grease represents an eco-friendly and healthy alternative. Grease made using vegetable oils with the required properties has the potential to bring about revolutionary changes. The present work focuses on the feasibility of using chemically modified blended rice bran oil (RBO) and Calophyllum inophyllum oil (CIO) as a bio-lubricant. The oils undergo a two-step modification process, involving a transesterification reaction followed by epoxidation. Significant improvements have been observed in the chemical properties (acid, peroxide, and iodine values) of transesterified epoxidized rice bran oil Calophyllum inophyllum oil mixture–50:50 (ETRCIO) when compared with Unmodified Rice bran oil Calophyllum inophyllum oil mixture–50:50 (RCIO). The acid value, peroxide value, and iodine value improved by 91.66%, 87.08%, and 15.78% respectively. The rheological, tribological, and chemical properties of the blended samples have been evaluated and compared to pure oils using American Society for Testing and Materials (ASTM) and Indian Standards (IS). Additionally, ETRCIO was used to develop a bio-grease, and its tribological properties were extensively analyzed. The mean coefficient of friction (COF) and wear scar diameter (WSD) of the ETRCIO grease sample improved by 10.20% and 29.32% respectively when compared with that of commercially available grease. These findings indicate that the ETRCIO bio-grease exhibits superior tribological properties in comparison to commercially available grease. Research highlights: • The study explores the potential of vegetable oils as a biodegradable and environmentally friendly alternative for producing lubricants, specifically focusing on rice bran oil and Calophyllum inophyllum oil. • The oils undergo a two-step chemical modification process (transesterification followed by epoxidation) to improve their thermal and oxidative stability, making them suitable for industrial use. • The chemically modified and blended oils showed significantly improved chemical properties. • The rheological, tribological, and chemical properties of the blended samples were evaluated according to ASTM, and IS standards and compared with those of pure oils. • A bio-grease was formulated using these chemically modified oils, exhibiting better tribological properties than commercially available grease, indicating its potential as an eco-friendly and health-conscious alternative to traditional mineral oil-based greases. [ABSTRACT FROM AUTHOR]

Context. Amylose is a type of resistant starch with numerous health benefits and industrial applications. Starch from maize (Zea mays L.) usually has an amylose content of ~25%. Aims. The aim was to develop high-amylose maize genotypes suitable for human consumption and adapted to Indian conditions. Methods. Marker-assisted backcross breeding was used to transfer the mutant ae1 allele froma high-amylose donor fromthe USA into the three parents (HKI 1344, HKI 1378, HKI 1348-6-2) of two high-yielding white maize hybrids (HM5 and HM12) grown in India. Key results. In converted lines, amylose content was 40.40-58.10% of total kernel starch, compared with 22.25-26.39% in parents. The percentage increase in amylose content was 63.70-153.03%. There was a significant amount of background recovery in each backcross generation: 66.80-79% in BC1F1, 72.85-88.60% in BC2F1, and 84.45-93.70% in BC2F2. Overall, the total kernel starch content was reduced (by ~22%) in the ae1-introgressed families. Conclusions. The converted lines developed in the study are enriched with kernel amylose while showing significant background recovery. Implications. The high-amylose lines developed may be highly beneficial for diabetic patients and in the bioplastics industry, and should be suitable for growing under Indian conditions. [ABSTRACT FROM AUTHOR]

The pervasive presence of microplastics within river ecosystems has a profound and often underestimated detrimental impact. These minuscule yet persistent particles have infiltrated diverse biological habitats, making their detrimental effects on aquatic life increasingly concerning worldwide. The ability of microplastics to accumulate within aquatic organisms further exacerbates this concern. Consequently, the monitoring of microplastic pollution in surface water environments has emerged as a crucial endeavour, offering invaluable insights into the extent of this ecological threat. This study delved into the contamination levels of microplastics within two bivalve species, Perna viridis and Villorita cyprinoides, along the Chandragiri River in Kerala and Karnataka, South-West India, spanning eight distinct locations. The investigation yielded a significant discovery, with a total of 667 microplastic particles extracted from 288 individuals. On average, each individual bivalve harboured approximately 2.31 ± 0.93 microplastic items. Notably, these microplastic particles exhibited a wide range of morphological characteristics, underscoring their diverse origins and pathways into the ecosystem. Furthermore, five polymer types of microplastics were unequivocally confirmed through FTIR-ATR analysis, shedding light on the types of plastics that pose a threat to the riverine ecosystem. The findings of this study contribute to a growing body of evidence highlighting the global threat of microplastic pollution, urging international collaboration and innovative solutions to prevent further contamination and remediate existing microplastic burdens in aquatic environments. Highlights: • Microplastic contamination is a major concern in river ecosystems. • Microplastic in two bivalve species were characterized at Chandragiri River India. • The microplastics had diverse shapes and were composed of five different polymers. • This study emphasizes the need to tackle river microplastic pollution. [ABSTRACT FROM AUTHOR]

In recent years, the pyrolysis technique has been adopted for converting non-degradable materials into biofuels and the yields of this process, oil and gas can be substituted as a fuel in CI engine. In this study, the medical waste plastics such as masks, gloves, personal protective equipment (PPE) kit and other plastics associated with hospitals were seen as the feedstock material for the pyrolysis process. It is collected from Government Medical College Hospital Villupuram, Tamil Nadu, India. The proximate and ultimate characterization of these wastes shows the percentage of volatile matter in the mask, gloves, and PPE kit are 81.2%, 79.3%, and 79.6%, respectively, and carbon percentage lies in the range of 75% to 78%, which ensures that the feedstock can be used in this process. The pyrolysis technique is carried out separately for all the collected feedstock such as mask, glove and other PPE kits. In this research, the mask waste showed a higher pyrolytic oil yield rate and is 80.3 wt% at 350°C than other plastics wastes. Further, FTIR of all the plastic waste confirms that pyrolytic oil is in acidic nature and it contains carboxylic acids and other heavier compounds, which are unstable in nature. To improve the fuel characteristics of pyrolytic oil, blending it with diesel requires the utilization of surfactants such as Span 80, Tween 60 and Atlox 4916. In this analysis, 5% of surfactant is mixed with 15% of pyrolytic oil and 80% of diesel. Among the various surfactants Atlox 4916, shows better fuel properties than other pyrolytic oil of plastic waste used in the analysis. Emulsifier fuel blend is prepared from different pyrolytic oils such as masks, gloves and PPE kit with Atlox 4916 surfactant, and MA, GA and PA, respectively. However, the pyrolytic oil from mask with Atlox 4916 surfactant blend has a (42.26 MJ/kg) higher calorific value. The evaluation of performance and emissions is conducted for the test fuels with surfactants derived from mask (MA), gloves (GA) and PPE (PA). Among these blends, MA showed better results in performance and emission behavior. The BTE of MA is 28.4%, which is 4.69% lower diesel and it is 2.077% and 2.95% higher than blend GA and PA. Blend MA shows lower emissions than other blends. [ABSTRACT FROM AUTHOR]

Plastic waste generation in India was around 9.4 million tonnes.year−1 in 2019 as compared to the global generation rate of more than 380 million tonnes.year−1 in 2019. Thus, India's contribution was around 3.1% of the global plastic waste generation. Globally, 42% of overall plastics produced are consumed by packaging sector and 17% by the construction sector. Whereas in India 35% is consumed by the packaging sector and 23% by construction sector. Bioplastic production is 1% out of 300 million tonnes of conventional plastics produced annually. This review attempts to analyse the plastic waste management rules, legislations, policies and practices in India during the period 1992–2020. The worldwide trend of bioplastic projects is reflected in studies in India, indicating a changed perception of bioplastics as an alternative source to conventional plastics. However, facilitating the implementation of conventional waste plastic processing plant and production of bioplastics in India involves challenges in terms of technology, developing a standardised framework and financial incentives. A legislative framework for the production of bioplastics in India should be developed alongwith an action plan for energy recovery from plastic waste. Markets for conventional plastic waste processing and production of bioplastic projects are not mature in India. This paper addresses the need for developing a roadmap towards efficient planning and sustainable solutions for both conventional plastics and bioplastics. [ABSTRACT FROM AUTHOR]

Background: In today's world, take-away materials predominantly consist of non-biodegradable plastics, known for their longevity and the release of harmful toxins during decomposition. To tackle this problem, the following article delves into the advantages and substitutes for plastic takeaway utensils and tableware, focusing on products made from palm (areca) and coconut tree by-products. It delves into the revival of traditional methods and knowledge rummage-sale in the southern then central parts of the India to create sustainable dining products. The article includes a market analysis, design considerations, life cycle analysis, and in-depth research on fabrication. Disposable plates, such as those made it from the polythene, polypropylene, polystyrene, polycarbonate, and polyvinyl chloride pose health risks, As a result of the release of noxious compounds, including melamine, vinyl chloride, biphenyl A, and phthalates. Therefore, an increasing trend is emerging in favour of utilizing use and throw plates crafted from plant leaves, which are both renewable and decomposable, however it is offering substantial antioxidant and medicinal properties. Results: In India, the classical way of using leaf dining plates carries profound cultural values, religious beliefs, medicinal, and socio-economic significance. The art of crafting these leaf plates serves as a livelihood for tribal communities residing in the states such as Orissa, Madhya Pradesh, Chhattisgarh, and Andhra Pradesh, These palm plates hold a crucial role in the offerings presented during religious rituals (Naivedyam) and the distribution of Prasadam to devotees. They find extensive use in serving meals at weddings, religious festivities, communal gatherings, and a wide array of other events. India embraces a variety of plant leaves not just as dining plates but also for their utility in wrapping, steaming, grilling, frying, and as materials for food packaging. Conclusion: In summary, biodegradable palm plates possess significant promise in the global market, granted they adhere to quality, design criteria. To promote the continued use of Leaf plates and discourage the adoption of plastic alternatives, it is imperative for the government to establish requisite regulations, which local authorities should rigorously enforce. Furthermore, spreading awareness among school and college students regarding the importance of these leaf plates is pivotal for nurturing their sustained adoption. [ABSTRACT FROM AUTHOR]

Microplastic pollution is a worldwide concern affecting all environmental matrices, including pristine lakes. Lentic lakes operate as a sink for microplastics (MPs), which interfere with a biogeochemical cycle and, therefore, deserve immediate attention. We present a comprehensive assessment of MPs contamination in the sediment and surface water of a geo-heritage site, Lonar lake (India). It is the third largest natural saltwater lake and only basaltic crater in the world formed by meteoric impact around 52,000 years ago. Mean MPs abundance in lakeshore sediment and surface water was 14.44 particles/kg and 2.66 particles/L, respectively. Small-sized MPs dominate the hypersaline region of the lake. Transparent and green fragments and filaments morphotypes were abundant. Most of the MPs in Lonar lake were secondary in origin. FTIR-ATR analysis revealed 16 types of polymers in the lake, of which polypropylene, polyvinyl chloride, polyethylene, high-density polyethylene, low-density polyethylene, polystyrene, and polyester were the most common. The overall pollution load index (PLI) for Lonar lake sediment and water was 1.39 and 2.58, respectively. Although all sampling stations had significant MPs pollution (PLI > 1), there was noticeable station-specific variability, which could be linked to anthropogenic activities. Irresponsible tourist behavior and religious activities, coupled with poor waste management are the leading causes of MPs contamination in the lake. The current work fills a gap in the investigation of MP pollution in a crater lake formed by a meteorite impact by being the first to provide a precise estimate of the MPs contamination in the Lonar lake. [ABSTRACT FROM AUTHOR]

Chemical reaction engineering (CRE) is vital to solve many of the pressing societal challenges—energy and energy transition, materials, food, mobility, and so forth, to meet the aspirational goals of developing country population in the face of climate change, changing demographics, and geopolitical challenges. Application of the core principles of CRE to the emerging societal challenges is creating new technologies and cost‐effective solutions by integrating the widely varied CRE activities into broad, powerful, systems descriptions with the help of interdisciplinary teams with broad expertise including chemistry, catalysis, chemical kinetics, transport phenomena, biology, applied mathematics and modeling, emerging data science technologies to design and optimize chemical/biochemical reactors. Such developments will be critical for CRE to play an important role in the emerging fourth industrial revolution—amalgamation of physical, digital, and biological worlds, where the velocity of disruption and acceleration of innovation are hard to comprehend or anticipate and such broadening of CRE discipline will be critical for the field to remain agile and relevant. This article describes some latest technical advances in Reliance Industries Ltd. using this philosophy to help achieve sustainable growth and Net Zero business targets. We will broadly discuss renewable hydrogen from novel biomass catalytic gasification, multizone catalytic cracking process to convert crude oil and low value hydrocarbon streams to petrochemical building blocks, an adsorption/desorption process for CO2 concentration and monetization from industrial flue gases. Furthermore, biotechnology advances in leveraging photosynthesis kinetics, synthetic biology, and genetic modifications for converting solar energy and carbon dioxide through algae production will be discussed to produce proteins, biomaterials, renewable biocrude, and so forth. We will also discuss new catalytic technologies to convert mixed plastic waste to stable oil and organic waste such as agri and municipal solid waste, and so forth, to biocrude for circular economy, and biodegradable plastics production to manage plastics pollution. [ABSTRACT FROM AUTHOR]

Plastics around the globe have been a matter of grave concern due to the unavoidable habits of human mankind. Taking waste statistics in India for the year 2019–20 into account, the data of 60 major cities show that the generation of plastic waste stands tall at around 26,000 tonnes/day, of which only about 60 % is recycled. A majority of the non‐recycled plastic waste is petrochemical‐based packaging materials that are non‐biodegradable in nature. Vegetative/food waste is another global issue, evidenced by vastly populated countries such as China and India accounting for 91 and 69 tonnes of food wastage, respectively in 2019. The mitigation of plastic packaging issues has led to key scientific developments, one of which is biodegradable materials. However, there is a way that these two waste‐related issues can be fronted as the analogy of "taking two shots with the same arrow". The presence of various bio‐compounds such as proteins, cellulose, starch, lipids, and waxes, etc., in food and vegetative waste, creates an opportunity for the development of biodegradable packaging films. Although these flexible packaging films have limitations in terms of mechanical, permeation, and moisture absorption characteristics, they can be fine‐tuned in order to convert the biobased raw material into a realizable packaging product. These strategies could work in replacing petrochemical‐based non‐biodegradable packaging plastics which are used in enormous quantities for various household and commercial packaging applications to combat the ever‐increasing pollution in highly populated countries. This paper presents a systematic review based on modern scientific tools of the literature available with a major emphasis on the past decade and aims to serve as a standard resource for the development of biodegradable packaging films from food/vegetative waste. [ABSTRACT FROM AUTHOR]

The Ganga is the largest river in India, serves as a lifeline for agriculture, drinking water, and religious rites. However, it became highly polluted due to the influx of industrial wastes and untreated sewages, leading to the decline of aquatic biodiversity. This study investigated the microbial diversity and plastic-xenobiotic degrading enzymes of six sediment metagenomes of river Ganga at Prayagraj (RDG, TSG, SDG) and Devprayag (KRG, BNG, BRG). The water quality parameters, higher values of BOD (1.8–3.7 ppm), COD (23–29.2 ppm) and organic carbon (0.18–0.51%) were recorded at Prayagraj. Comparative analysis of microbial community structure between Prayagraj and Devprayag revealed significant differences between Bacteroidetes and Firmicutes, which emerging as the predominant bacterial phyla across six sediment samples. Notably, their prevalence was highest in the BRG samples. Furthermore, 25 OTUs at genus level were consistent across all six samples. Alpha diversity exhibited minimal variation among samples, while beta diversity indicated an inverse relationship between species richness and diversity. Co-occurrence network analysis established that genera from the same and different groups of phyla show positive co-relations with each other. Thirteen plastic degrading enzymes, including Laccase, Alkane-1 monooxygenase and Alkane monooxygenase, were identified from six sediment metagenomes of river Ganga, which can degrade non-biodegradable plastic viz. Polyethylene, Polystyrene and Low-density Polyethelene. Further, 18 xenobiotic degradation enzymes were identified for the degradation of Bisphenol, Xylene, Toluene, Polycyclic aromatic hydrocarbon, Styrene, Atrazene and Dioxin etc. This is the first report on the identification of non-biodegradable plastic degrading enzymes from sediment metagenomes of river Ganga, India. The findings of this study would help in pollution abatement and sustainable management of riverine ecosystem. [Display omitted] • Metagenomic study of microbial communities in sediments of river Ganga stretches. • Highest concentrations of Mn, Fe, and Cr were observed in the polluted sites. • Bacteroidota and Chloroflexota were predominant in all sediment samples. • First report reveals the presence of 13 plastic & 18 xenobiotic degradation enzymes. [ABSTRACT FROM AUTHOR]

Microplastics are ubiquitous, and their widespread prevalence in the ecosphere has generated concerns about their potential effects on terrestrial and aquatic organisms. However, studies pertaining to ecologically sensitive freshwater ecosystems, such as Ramsar wetlands, is scarce. Therefore, the study was conducted in Loktak, the world's only floating lake, and one of the largest wetland in the Indian Himalayan region. The wetland's degradation and pollution have resulted its inclusion in the Montreux Record, underscoring the need for studying this eco-sensitive freshwater system. This work investigated the (i) abundance, morphotype and size of microplastics in fish, and (ii) chemical composition of the microplastics consumed and accumulated in the fish of Loktak lake. Fish samples representing eight species were collected and analyzed for microplastics. Results revealed that ∼91% of the sampled fish ingested microplastics. Fragment was identified as the predominant morphotype (∼82%). Plastic polymers including polyamide (PA), polystyrene (PS), polycarbonate (PC) and carboxymethyl cellulose (CMC) were detected. The occurrence of heavy metals - chlorine (Cl), palladium (Pd), sodium (Na), zinc (Zn), lead (Pb) and copper (Cu) suggests their adhesion on the microplastics. The occurrence of microplastics in fish indicates pollution in the lake and poses a potential health risks to humans through consumption. Therefore, implementing comprehensive management approaches is imperative to mitigate this emerging pollution and uphold the ecological integrity of the Ramsar site. Substantial information on microplastics and their potential human exposure through fish consumption, particularly in the Indian Himalayan region, remains to be assessed, underscoring the need for extensive study. [Display omitted] • First report on microplastic pollution in fishes from the Indian Himalayan Region. • Ninety one percent of the studied fish individuals were detected with microplastics. • Microplastic fragments were the predominant morphotype in the fish. • No relation was found between fish body length/weight with the microplastic content. [ABSTRACT FROM AUTHOR]

In the present study, the occurrence of microplastics (MPs) in the gut, gill, and muscle of edible fish Stolephorus indicus sampled from Tuticorin coastal regions of Tamilnadu, India was investigated. We recorded a total of 689 MPs which includes 510 and 179 MPs from males and females respectively. The total abundance of MPs was significantly (P < 0.05) higher in the gut followed by gills and muscle. The sex-wise distribution of average MPs showed high in the females' gut and compared to that in males. Further, the length wise distribution of MPs was higher in the muscle in both male and female fish, followed by other organs. The predominance of MPs in tissues were transparent and blue colour with fibers and fragments in both males and females. Besides, polyethylene terephthalate and nylon were evidenced by the Fourier-transform infrared spectroscopy spectrum in all organs of fishes. • Microplastics (MPs) in the gut, gills, and muscle of Stolephorus indicus was recorded. • Females had a high abundance of MPs in the gut compared to males. • Mean lengths of MPs were high in the muscles of both male and female fishes. • Polyethylene terephthalate and nylon were identified in all organs of fish. [ABSTRACT FROM AUTHOR]

Scylla serrata plays a crucial role in India's seafood exports yet there exists limited understanding on the occurrence of microplastics (MPs) in these crabs. In this baseline study, we examined the presence of microplastics in the digestive tracts of S. serrata collected from the Kota mangroves, southwestern coast of India. Our analysis revealed the presence of 264 MPs in all the samples with an average (± standard deviation) of 29.33 (±11.53) MPs/Individual. The most dominant categories were fibres (98.86 %) and fragments (1.14 %). Primarily 0.1–0.3 mm (50.90 %) and 0.3–1 mm (37.65 %) size range dominated. The predominant polymers were polypropylene (33.71 %), high-density polyethylene (31.44 %), and polyethylene terephthalate (17.80 %). Scanning electron microscopy revealed extensive weathering on the surface of the microplastics. Risk assessments indicated severe risks to S. serrata due to microplastic ingestion emphasizing the need to protect delicate ecosystems like mangroves and the biota within. [Display omitted] • A first report on microplastics in Scylla serrata from a mangrove forest in India. • The microplastics were dominated by 0.3–1 mm and 0.1–0.3 mm-sized fibres. • Polypropylene and high-density polyethylene were the dominant polymers. • The Polymer Hazard Index indicated a severe risk to the mud crabs. • The data are important as India exports a large amount of Scylla serrata. [ABSTRACT FROM AUTHOR]

The environmental input of microplastics from personal care products has received significant attention; however, less focus has been paid to oral healthcare products. The present study assessed the occurrence of microplastics in commercially available oral healthcare products such as toothbrushes, toothpastes, toothpowder, mouthwash, dental floss, and mouth freshener spray that have a pan-India distribution. The extracted microplastics were quantified and characterised using a microscope and ATR-FTIR. All products showed microplastic contamination, where toothbrushes showed the maximum particles (30–120 particles/brush) and mouth freshener sprays (0.2–3.5 particles/ml) had the least abundance. Fragments, fibres, beads, and films were the various shapes of microplastics observed, where fragments (60%) were dominant. Various colours such as pink, green, blue, yellow, black, and colourless were observed, where colourless (40%) particles were dominant. Microplastics were categorized into three sizes: <0.1 mm (63%), 0.1–0.3 mm (35%), and >0.3 mm (2%). Four major types of polymers, such as polyethylene (52%), polyamide (30%), polyethylene terephthalate (15%), and polybutylene terephthalate (3%), were identified. Risk assessment studies such as Daily Microplastics Emission (DME), Annual Microplastics Exposure (AME), and Polymer Hazard Index (PHI) were carried out. The DME projection for India was the highest for mouthwash (74 billion particles/day) and the least for mouth freshener sprays (0.36 billion particles/day). The AME projection for an individual was the highest in toothbrushes (48,910 particles ind.−1 yr.−1) and the least in mouth freshener sprays (111 particles ind.−1 yr.−1). PHI shows that the identified polymers fall under the low-to high-risk categories. This study forecasts the community health risks linked to microplastics in oral healthcare products and suggests mitigation strategies. It has the potential to shape environmental policy development in response. [Display omitted] • Microplastics were observed in six types of oral healthcare products (OHPs). • Daily microplastic emission from OHPs in India was predicted to be 74 billion particles/day. • Predicted annual microplastic exposure from OHPs in India was 48,910 particles ind.−1 yr.−1. • Polymer hazard index classified the identified polymers as low-to high-risk. • Microplastic mitigation measures for OHPs have been proposed. [ABSTRACT FROM AUTHOR]

Sundarbans, a Ramsar site of India is contaminated with heterogeneous microplastic wastes. Boddart's goggle eye mudskipper and Rubicundus eelgoby, were common gobies of Sundarbans estuary which accumulated microplastics during their normal biological activities. We estimated the abundance of microplastics in water, sediment; skin, gills, bucco-opercular cavity and gastrointestinal tract of these two goby fishes. Microplastic load estimated in gobies were 0.84 and 2.62 particles per fish species with a dominance of transparent, fibrous microplastics with 100–300 μm in length. ATR-FTIR and Raman spectroscopy revealed polyethylene as prevalent polymer. Surface degradations and adsorption of contaminants on microplastic surface were investigated by SEM-EDX analysis. Presence of hazardous polymers influenced high polymer hazard index and potential ecological risk index which indicated acute environmental threat to Sundarbans estuary and its resident organisms. Current study will provide a new information base on the abundance of microplastics and its ecological hazard in this biosphere reserve. [Display omitted] • MPs in sediment, water, fishes (gills, bucco-opercular cavity, gut, skin) • Transparent and fibrous MPs are prevalent in water and fish. • PE and PET MPs are the major contaminants of water, sediment and fish. • SEM-EDX indicated adsorbed metals on MP surface. • PHI and PERI values indicated site specific high ecological risk. [ABSTRACT FROM AUTHOR]

The global adoption of biodegradable and compostable plastics obtained from biomass-derived monomers, we argue in this account, is now close to the inflection point. The first industrially significant impact will affect the packaging segment of the global chemical industry. In this process, China and India will play a pivotal role. Selected guidelines aiming to foster development of bioplastics industry in both developed and developing nations are provided. [ABSTRACT FROM AUTHOR]

This study undertook to investigate the occurrence of microplastics (MPs) in the high and low-tide sediments of five coastal areas in Tamil Nadu, India. The abundance of microplastics vary from 439 ± 172 to 119 ± 72 (HTL) and 179 ± 68 to 33 ± 30 (LTL) items kg−1 of sediments. The MP polymers found in the study sites are Polyethylene (73.2%), polypropylene (13.8%), nylon (8.2%), polystyrene (2.8%) and polyester (2%). The weathered surfaces might act as high-capacity carriers and this was confirmed by SEM-EDAX. The results of an analysis of the textures of the sediments do not ascribe any influence on microplastic abundance. The recreation, religious and fishing activities are the major contributors to plastic pollution in these beaches, which is borne out by the high abundance of MPs in the study sites. A regular and permanent waste management system should be put in place for the protection of beaches. Unlabelled Image • Microplastics in the high and low tide sediments were quantified and characterized. • Polyethylene was present abundantly in all the study sites. • The carbonyl index values vary from 0.07 to 0.70 for PE and 0.20 to 3.30 for PP. • Weathering pattern and adhering chemicals were confirmed by SEM-EDAX. [ABSTRACT FROM AUTHOR]

Personal protective equipment (PPE) use has increased because of COVID-19, producing more microplastics (MPs). The pandemic's impact on MP pollution in Indian rivers is little understood. In this study, the Netravathi River in Karnataka was investigated for the spatiotemporal distribution of MPs. The MPs abundance, size, and categories varied seasonally, with a higher concentration during the monsoon seasons. The reduction in rainfall during MON20 and the COVID-19 lockdown can be the reasons for the significant decrease in the MP concentration when compared to MON19. Polyethylene and polyethylene terephthalate were the most abundant polymers, with a shift from polyethylene to the latter (74 %) during post-monsoon season post-lockdown. The situation of MP pollution in Western Ghats can be mitigated with the aid of appropriate waste management of plastic trash and greater public awareness about the disposal of single-use plastics, which has risen significantly during the COVID-19 pandemic. • COVID-19 increases microplastic pollution: evidence from River Netravathi (India). • Seasonal variation was reported in microplastic abundance. • Polyethylene (PE) and Polyethylene terephthalate (PET) were the dominant polymers. • SEM-EDS analysis revealed cracks, scratches, and heavy metals on microplastics. • There must be increased public awareness about safe disposal of single use plastics. [ABSTRACT FROM AUTHOR]

Plastics and microplastics have been quantified and characterised at disposal sites of abandoned fishing boats and along the high-water line (HWL) of a fish landing centre in Chellanam, India. Fibreglass-reinforced plastic (FRP) made a greater contribution to the plastic pool at the disposal sites (~ 4.5 n m−2 and 18 g m−2) than the HWL (~ 0.25 n m−2 and < 1 g m−2) and was an abundant component of the microplastic pool at the former. Infrared analysis of micro-sized FRPs revealed various resins (e.g., alkyd, polyester, epoxy), while X-ray fluorescence analysis of the painted surfaces of meso-sized FRPs returned variable concentrations of copper and lead. Concentrations of Pb were high enough to contaminate sand up to ~400 mg kg−1. The relatively high density of FRP and its association with glass fibres and metal-bearing paints results in particles with potentially very different fates and toxicities to more "conventional" (non-composite) thermoplastics. • Little information exists on fibreglass-reinforced plastic (FRP) as marine litter. • Different sizes of FRP were found on a beach impacted by fishing boat abandonment. • FRP can make an important contribution to the microplastic pool. • Lead in painted surfaces of FRP are sufficient to significantly contaminate sand. • FRP requires further study because of its association with glass fibres and metals. [ABSTRACT FROM AUTHOR]

Microplastics, as growing contaminants in current scenario, are an ecological threat to the surface water ecosystem. Our primary goal is to investigate the identification, characterization, distribution and abundance of microplastics throughout India's east coast, from Ennore to Kovalam. In accordance with the NOAA protocol, microplastics were examined in surface water samples. At all sampling sites, polymers like polyethylene (43%), polypropylene (42%) and polystyrene (15%) were often found. Surface water (total sample location = 34) were found to be contaminated with various types of microplastics ranging from 6 to 30 items/Location with a mean value of 12 items/Location. Microplastics examined from surface water in a variety of colours, including white (26%), black (16%), grey (12%), red (14%), blue (12%), yellow (10%) and green (10%). Microplastics identified by stereo microscope as well as analytical methods such as SEM and FTIR were utilized to explore the characterization of microplastics. The following are the most typical types of microplastic found in surface water: Fibres (59%), films (24%), fragments (10%) and pellets (7%). This research work is a baseline for study about microplastics contamination site from Ennore to Kovalam on East Coast of India. • Microplastics distribution has been identified in surface water ecosystem. • Major Polymers found were polyethylene, polypropylene and Polystyrene. • Microplastics concentration in the order of fibres > films > fragments > pellets. • Smaller size (>0.3 mm) microplastics were found most significantly in study area. [ABSTRACT FROM AUTHOR]

Abstract: Moderately haloalkaliphilic Halomonas campisallis MCM B-1027 isolated from the alkaline lake of Lonar, India was found to produce a biodegradable polymer, polyhydroxyalkanoate (PHA). Scale up production of PHA from H. campisalis MCM B-1027 was carried out in 120L stainless steel (SS) fermenter using 85L production medium with a yield of 51.56% PHA on dry cell weight basis. The recovery of PHA was studied by several methods such as solvent extraction of the polymer, chemical digestion of the non-PHA biomass and mechanical disruption of the cells. Highest rate of PHA recovery obtained was 63mg/h with solvent extraction using rotary film evaporator. Further optimization of extraction of PHA from dry cells in chloroform using 10L rotavapor was carried out. L9 orthogonal array was chosen to study the influence of time, rotation and temperature at three levels along with their interactive effects on extraction process. Maximum PHA recovery of 84.47% was obtained at 25rpm, 60°C, within 3h. Time factor had highest 84.11% contribution in the extraction process. This study is the first report on model for batch extraction of PHA and its validation based on second-order mechanism developed to predict the saturation capacity of the solvent, initial rate of extraction at different temperatures and activation energy of the process. [Copyright &y& Elsevier]

Abstract: Several microorganisms produce polyhydroxyalkanoates (PHA). They are accumulated intracellularly as energy storage compounds. The PHAs are of interest because of their potential in biomedical applications. Halophilic bacteria and archaea are known to produce polyhydroxybutyrate (PHB). This paper describes production of a biodegradable copolymer, PHB-co-PHV by a moderately haloalkalitolerant Halomonas campisalis, isolated from Lonar Lake, India. The production of PHA was in the range of 45–81% on dry cell weight basis when the organism was grown in a production medium containing 1% (w/v) maltose and 0.1% (w/v) yeast extract, at pH ranging from 6 to 9 with an inoculum density of 105–107 cells/ml of medium, for incubation period of 15–30h and at 37°C. The polymer produced by the organism is a hydroxyester with molecular weight of 1.3014×106. Its melting temperature was 171°C. The 1H NMR analysis revealed that the polymer was a copolymer of PHB-co-PHV. This could be achieved by providing simple carbon source viz. maltose. [ABSTRACT FROM AUTHOR]