Microplastics, their abundance, and distribution in water and sediments in North Chennai, India: An assessment of pollution risk and human health impacts.

Plastic particles, measuring <5 mm in size, mainly originate from larger plastic debris undergoing degradation, fragmenting into even smaller fragments. The goal was to analyze the spatial diversity and polymer composition of microplastics (MPs) in North Chennai, South India, aiming to evaluate their prevalence and features like composition, dimensions, color, and shape. In 60 sediment samples, a combined count of 1589 particles were detected, averaging 26 particles per 5 g-1 of dry sediment. The water samples from the North Chennai vicinity encompassed a sum of 1588 particles across 71 samples, with an average of 22 items/L. The majority of MPs ranged in size from 1 mm to 500 µm. The ATR-FTIR results identified the predominant types of MPs as polystyrene, polyvinyl chloride, polyethylene, polyethylene terephthalate, and polypropylene in sediment and water. The spatial variation analysis revealed high MPs concentration in landfill sites, areas with dense populations, and popular tourist destinations. The pollution load index in water demonstrated that MPs had contaminated all stations. Upon evaluating the polymeric and pollution risks, it was evident that they ranged from 5.13 to 430.15 and 2.83 to 15,963.2, which is relatively low to exceedingly high levels. As the quantity of MPs and hazardous polymers increased, the level of pollution and corresponding risks also escalated significantly. The existence of MPs in lake water, as opposed to open well water, could potentially pose a cancer risk for both children and adults who consume it. Detecting MPs in water samples highlights the significance of implementing precautionary actions to alleviate the potential health hazards they create.

Ecological disturbances and abundance of anthropogenic pollutants in the aquatic ecosystem: Critical review of impact assessment on the aquatic animals.

Anthropogenic toxins are discharged into the environment and distributed through a variety of environmental matrices. Trace contaminant detection and analysis has advanced dramatically in recent decades, necessitating further specialized technique development. These pollutants can be mobile and persistent in small amounts in the environment, and ecological receptors will interact with it. Despite the fact that few researches have been undertaken on invertebrate exposure, accumulation, and biological implications, it is apparent that a wide range of pollutants can accumulate in the tissues of aquatic insects, earthworms, amphipod crustaceans, and mollusks. Due to long-term stability during long-distance transit, a number of chemical and microbiological agents that were not previously deemed pollutants have been found in various environmental compartments. The uptake of such pollutants by the aquatic organism is done through the process of bioaccumulation when dangerous compounds accumulate in living beings while biomagnification is the process of a pollutant becoming more hazardous as it moves up the trophic chain. Organic and metal pollution harms animals of every species studied so far, from bacteria to phyla in between. The environmental protection agency says these poisons harm humans as well as a variety of aquatic organisms when the water quality is sacrificed in typical wastewater treatment systems. Contrary to popular belief, treated effluents discharged into aquatic bodies contain considerable levels of Anthropogenic contaminants. This evolution necessitates a more robust and recent advancement in the field of remediation and their techniques to completely discharge the various organic and inorganic contaminants.

Assessment, characterization, and quantification of microplastics from river sediments.

Microplastic (MP), as a pollutant, is currently posing a biological hazard to the aquatic environment. The study aims to isolate, quantify, and characterize the MP pollutants in sediment samples from 14 study sites at Kaveri River, Killa Chinthamani, Tiruchirappalli, South India. With Sediment-MP Isolation (SMI) unit, density separation was done with a hydrogen peroxide solution. Four forms of MPs namely, fragments, films, foams, and fibers with orange, white, green, and saffron red were observed. The plenitude and distribution of four forms of MPs and natural substrates were geometrically independent, with large amounts of microfragments within the research region accounting for 79.72% variation by Principal Component Analysis. FT-IR analyses of MPs showed the presence of polyamide, polyethylene, polyethylene glycol, polyethylene terephthalate, polypropylene, and polystyrene. Additionally, the scanning electron microscopic analysis revealed that the MPs have differential surface morphology with rough surfaces, porous structures, fissures, and severe damage. Most MPs comprised Si, Mg, Cu, and Al, according to energy dispersive X-ray analyses. The combined SMI, instrumental analyses and evaluation (heat map) of MPs in river sediments help assess contamination levels and types of MPs. The findings might provide an insight into the status of MPs in Kavery River sediments that could help in formulating regulations for MPs reduction and contamination in rivers eventually to protect the environment.

Low-cost and eco-friendly synthesis of silver nanoparticles using coconut (Cocos nucifera) oil cake extract and its antibacterial activity.

The present study reports the simple, inexpensive, eco-friendly synthesis of silver nanoparticles (AgNPs) using coconut oil cake extract. Scanning electron microscopy-energy dispersive spectroscopy peak at 3 keV confirmed the presence of silver. Transmission electron micrograph showed that nanoparticles are mostly circular with an average size of 10-70 nm. The results of the X-ray powder diffraction analysis (2θ = 46.2, 67.4 and 76.8) indicated the crystal nature of the AgNPs. Fourier transform infrared spectroscopy analysis indicates that proteins present in the oilcake extract could be responsible for the reduction of silver ions. The synthesized AgNPs (1-4 mm) reduced the growth rate of multi-antibiotic-resistant bacteria such as Aeromonas sp., Acinetobacter sp. and Citrobacter sp. isolated from livestock wastewater.